Revert "compiler: saturate float-to-int conversions"

This reverts commit a867b56e5f.

.circleci/config.yml

@@ -80,12 +80,12 @@ commands:
     steps:
       - restore_cache:
           keys:
-            - wasi-libc-sysroot-v4
+            - wasi-libc-sysroot-v3
       - run:
           name: "Build wasi-libc"
           command: make wasi-libc
       - save_cache:
-          key: wasi-libc-sysroot-v4
+          key: wasi-libc-sysroot-v3
           paths:
             - lib/wasi-libc/sysroot
   test-linux:
@@ -108,10 +108,10 @@ commands:
       - run: go install -tags=llvm<<parameters.llvm>> .
       - restore_cache:
           keys:
-            - wasi-libc-sysroot-systemclang-v3
+            - wasi-libc-sysroot-systemclang-v2
       - run: make wasi-libc
       - save_cache:
-          key: wasi-libc-sysroot-systemclang-v3
+          key: wasi-libc-sysroot-systemclang-v2
           paths:
             - lib/wasi-libc/sysroot
       - run: go test -v -tags=llvm<<parameters.llvm>> ./cgo ./compileopts ./compiler ./interp ./transform .
@@ -132,7 +132,6 @@ commands:
       - run:
           name: "Install apt dependencies"
           command: |
-            sudo apt-get update
             sudo apt-get install \
                 gcc-arm-linux-gnueabihf \
                 libc6-dev-armel-cross \
@@ -154,7 +153,7 @@ commands:
       - llvm-source-linux
       - restore_cache:
           keys:
-            - llvm-build-11-linux-v2-assert
+            - llvm-build-11-linux-v1-assert
       - run:
           name: "Build LLVM"
           command: |
@@ -169,7 +168,7 @@ commands:
               make ASSERT=1 llvm-build
             fi
       - save_cache:
-          key: llvm-build-11-linux-v2-assert
+          key: llvm-build-11-linux-v1-assert
           paths:
             llvm-build
       - run: make ASSERT=1
@@ -191,7 +190,6 @@ commands:
       - run:
           name: "Install apt dependencies"
           command: |
-            sudo apt-get update
             sudo apt-get install \
                 gcc-arm-linux-gnueabihf \
                 libc6-dev-armel-cross \
@@ -213,7 +211,7 @@ commands:
       - llvm-source-linux
       - restore_cache:
           keys:
-            - llvm-build-11-linux-v2-noassert
+            - llvm-build-11-linux-v1-noassert
       - run:
           name: "Build LLVM"
           command: |
@@ -228,7 +226,7 @@ commands:
               make llvm-build
             fi
       - save_cache:
-          key: llvm-build-11-linux-v2-noassert
+          key: llvm-build-11-linux-v1-noassert
           paths:
             llvm-build
       - build-wasi-libc
@@ -270,8 +268,8 @@ commands:
       - run:
           name: "Install dependencies"
           command: |
-            curl https://dl.google.com/go/go1.16.darwin-amd64.tar.gz -o go1.16.darwin-amd64.tar.gz
-            sudo tar -C /usr/local -xzf go1.16.darwin-amd64.tar.gz
+            curl https://dl.google.com/go/go1.15.5.darwin-amd64.tar.gz -o go1.15.5.darwin-amd64.tar.gz
+            sudo tar -C /usr/local -xzf go1.15.5.darwin-amd64.tar.gz
             ln -s /usr/local/go/bin/go /usr/local/bin/go
             HOMEBREW_NO_AUTO_UPDATE=1 brew install qemu
       - install-xtensa-toolchain:
@@ -292,7 +290,7 @@ commands:
             - llvm-project
       - restore_cache:
           keys:
-            - llvm-build-11-macos-v2
+            - llvm-build-11-macos-v1
       - run:
           name: "Build LLVM"
           command: |
@@ -304,17 +302,17 @@ commands:
               make llvm-build
             fi
       - save_cache:
-          key: llvm-build-11-macos-v2
+          key: llvm-build-11-macos-v1
           paths:
             llvm-build
       - restore_cache:
           keys:
-            - wasi-libc-sysroot-macos-v3
+            - wasi-libc-sysroot-macos-v2
       - run:
           name: "Build wasi-libc"
           command: make wasi-libc
       - save_cache:
-          key: wasi-libc-sysroot-macos-v3
+          key: wasi-libc-sysroot-macos-v2
           paths:
             - lib/wasi-libc/sysroot
       - run:
@@ -342,6 +340,18 @@ commands:
             - /go/pkg/mod
 
 jobs:
+  test-llvm9-go111:
+    docker:
+      - image: circleci/golang:1.11-buster
+    steps:
+      - test-linux:
+          llvm: "9"
+  test-llvm10-go112:
+    docker:
+      - image: circleci/golang:1.12-buster
+    steps:
+      - test-linux:
+          llvm: "10"
   test-llvm10-go113:
     docker:
       - image: circleci/golang:1.13-buster
@@ -360,12 +370,6 @@ jobs:
     steps:
       - test-linux:
           llvm: "11"
-  test-llvm11-go116:
-    docker:
-      - image: circleci/golang:1.16-buster
-    steps:
-      - test-linux:
-          llvm: "11"
   assert-test-linux:
     docker:
       - image: circleci/golang:1.14-stretch
@@ -387,10 +391,11 @@ jobs:
 workflows:
   test-all:
     jobs:
+      - test-llvm9-go111
+      - test-llvm10-go112
       - test-llvm10-go113
       - test-llvm10-go114
       - test-llvm11-go115
-      - test-llvm11-go116
       - build-linux
       - build-macos
       - assert-test-linux

.gitignore

@@ -19,10 +19,3 @@ src/device/kendryte/*.s
 vendor
 llvm-build
 llvm-project
-
-# Ignore files generated by smoketest
-test.gba
-test.hex
-test.nro
-test.wasm
-wasm.wasm

BUILDING.md

@@ -23,7 +23,7 @@ different guide:
 LLVM, Clang and LLD are quite light on dependencies, requiring only standard
 build tools to be built. Go is of course necessary to build TinyGo itself.
 
-  * Go (1.13+)
+  * Go (1.11+)
   * Standard build tools (gcc/clang)
   * git
   * CMake
@@ -43,6 +43,11 @@ You can also store LLVM outside of the TinyGo root directory by setting the
 `LLVM_BUILDDIR`, `CLANG_SRC` and `LLD_SRC` make variables, but that is not
 covered by this guide.
 
+TinyGo uses Go modules, so if you clone TinyGo inside your GOPATH (and are using
+Go below 1.13), make sure that Go modules are enabled:
+
+    export GO111MODULE=on
+
 ## Build LLVM, Clang, LLD
 
 Before starting the build, you may want to set the following environment

CHANGELOG.md

@@ -1,93 +1,3 @@
-0.17.0
-
----
-* **command line**
-  - switch to LLVM 11 for static builds
-  - support gdb debugging with AVR
-  - add support for additional openocd commands
-  - add `-x` flag to print commands
-  - use LLVM 11 by default when linking LLVM dynamically
-  - update go-llvm to use LLVM 11 on macOS
-  - bump go.bug.st/serial to version 1.1.2
-  - do not build LLVM with libxml to work around a bugo on macOS
-  - add support for Go 1.16
-  - support gdb daemonization on Windows
-  - remove support for LLVM 9, to fix CI
-  - kill OpenOCD if it does not exit with a regular quit signal
-  - support `-ocd-output` on Windows
-* **compiler**
-  - `builder`: parallelize most of the build
-  - `builder`: remove unused cacheKey parameter
-  - `builder`: add -mcpu flag while building libraries
-  - `builder`: wait for running jobs to finish
-  - `cgo`: add support for variadic functions
-  - `compiler`: fix undefined behavior in wordpack
-  - `compiler`: fix incorrect "exported function" panic
-  - `compiler`: fix non-int integer constants (fixing a crash)
-  - `compiler`: refactor and add tests
-  - `compiler`: emit a nil check when slicing an array pointer
-  - `compiler`: saturate float-to-int conversions
-  - `compiler`: test float to int conversions and fix upper-bound calculation
-  - `compiler`: support all kinds of deferred builtins
-  - `compiler`: remove ir package
-  - `compiler`: remove unnecessary main.main call workaround
-  - `compiler`: move the setting of attributes to getFunction
-  - `compiler`: create runtime types lazily when needed
-  - `compiler`: move settings to a separate Config struct
-  - `compiler`: work around an ARM backend bug in LLVM
-  - `interp`: rewrite entire package
-  - `interp`: fix alignment of untyped globals
-  - `loader`: use name "main" for the main package
-  - `loader`: support imports from vendor directories
-  - `stacksize`: add support for DW_CFA_offset_extended
-  - `transform`: show better error message in coroutines lowering
-* **standard library**
-  - `machine`: accept configuration struct for ADC parameters
-  - `machine`: make I2C.Configure signature consistent
-  - `reflect`: implement PtrTo
-  - `runtime`: refactor to simplify stack switching
-  - `runtime`: put metadata at the top end of the heap
-* **targets**
-  - `atsam`: add a length check to findPinPadMapping
-  - `atsam`: improve USBCDC
-  - `atsam`: avoid infinite loop when USBCDC is disconnected
-  - `avr`: add SPI support for Atmega based chips
-  - `avr`: use Clang for compiling C and assembly files
-  - `esp32`: implement task based scheduler
-  - `esp32`: enable the FPU
-  - `esp8266`: implement task based scheduler
-  - `esp`: add compiler-rt library
-  - `esp`: add picolibc
-  - `nrf`: refactor code a bit to reduce duplication
-  - `nrf`: use SPIM peripheral instead of the legacy SPI peripheral
-  - `nrf`: update nrfx submodule to latest commit
-  - `nrf52840`: ensure that USB CDC interface is only initialized once
-  - `nrf52840`: improve USBCDC
-  - `stm32`: use stm32-rs SVDs which are of much higher quality
-  - `stm32`: harmonization of UART logic
-  - `stm32`: replace I2C addressable interface with simpler type
-  - `stm32`: fix i2c and add stm32f407 i2c
-  - `stm32`: revert change that adds support for channels in interrupts
-  - `wasm`: implement a growable heap
-  - `wasm`: fix typo in wasm_exec.js, syscall/js.valueLoadString()
-  - `wasm`: Namespaced Wasm Imports so they don't conflict across modules, or reserved LLVM IR
-  - `wasi`: support env variables based on libc
-  - `wasi`: specify wasi-libc in a different way, to improve error message
-* **boards**
-  - `matrixportal-m4`: add support for board Adafruit Matrix Portal M4
-  - `mkr1000`: add this board
-  - `nucleo-f722ze`: add this board
-  - `clue`: correct volume name and add alias for release version of Adafruit Clue board
-  - `p1am-100`: add support for the P1AM-100 (similar to Arduino MKR)
-  - `microbit-v2`: add initial support based on work done by @alankrantas thank you!
-  - `lgt92`: support for STM32L0 MCUs and Dragino LGT92 device
-  - `nicenano`: nice!nano board support
-  - `circuitplay-bluefruit`: correct internal I2C pin mapping
-  - `clue`: correct for lack of low frequency crystal
-  - `digispark`: split off attiny85 target
-  - `nucleo-l552ze`: implementation with CLOCK, LED, and UART
-  - `nrf52840-mdk-usb-dongle`: add this board
-
 0.16.0
 ---
 

Dockerfile

@@ -1,10 +1,10 @@
-# TinyGo base stage installs the most recent Go 1.15.x, LLVM 11 and the TinyGo compiler itself.
+# TinyGo base stage installs the most recent Go 1.15.x, LLVM 10 and the TinyGo compiler itself.
 FROM golang:1.15 AS tinygo-base
 
 RUN wget -O- https://apt.llvm.org/llvm-snapshot.gpg.key| apt-key add - && \
-    echo "deb http://apt.llvm.org/buster/ llvm-toolchain-buster-11 main" >> /etc/apt/sources.list && \
+    echo "deb http://apt.llvm.org/buster/ llvm-toolchain-buster-10 main" >> /etc/apt/sources.list && \
     apt-get update && \
-    apt-get install -y llvm-11-dev libclang-11-dev lld-11 git
+    apt-get install -y llvm-10-dev libclang-10-dev lld-10 git
 
 COPY . /tinygo
 
@@ -29,7 +29,7 @@ COPY --from=tinygo-base /tinygo/targets /tinygo/targets
 
 RUN cd /tinygo/ && \
     apt-get update && \
-    apt-get install -y make clang-11 libllvm11 lld-11 && \
+    apt-get install -y make clang-10 libllvm10 lld-10 && \
     make wasi-libc
 
 # tinygo-avr stage installs the needed dependencies to compile TinyGo programs for AVR microcontrollers.
@@ -61,7 +61,7 @@ COPY --from=tinygo-base /tinygo/lib /tinygo/lib
 
 RUN cd /tinygo/ && \
     apt-get update && \
-    apt-get install -y apt-utils make clang-11 && \
+    apt-get install -y apt-utils make clang-10 && \
     make gen-device-nrf && make gen-device-stm32
 
 # tinygo-all stage installs the needed dependencies to compile TinyGo programs for all platforms.
@@ -73,7 +73,7 @@ COPY --from=tinygo-base /tinygo/lib /tinygo/lib
 
 RUN cd /tinygo/ && \
     apt-get update && \
-    apt-get install -y apt-utils make clang-11 binutils-avr gcc-avr avr-libc && \
+    apt-get install -y apt-utils make clang-10 binutils-avr gcc-avr avr-libc && \
     make gen-device
 
 CMD ["tinygo"]

LICENSE

@@ -1,7 +1,7 @@
-Copyright (c) 2018-2021 TinyGo Authors. All rights reserved.
+Copyright (c) 2018-2020 TinyGo Authors. All rights reserved.
 
 TinyGo includes portions of the Go standard library.
-Copyright (c) 2009-2021 The Go Authors. All rights reserved.
+Copyright (c) 2009-2020 The Go Authors. All rights reserved.
 
 TinyGo includes portions of LLVM, which is under the Apache License v2.0 with
 LLVM Exceptions. See https://llvm.org/LICENSE.txt for license information.

Makefile

@@ -54,53 +54,39 @@ ifeq ($(OS),Windows_NT)
     CGO_LDFLAGS += -static -static-libgcc -static-libstdc++
     CGO_LDFLAGS_EXTRA += -lversion
 
-    LIBCLANG_NAME = libclang
+    LIBCLANG_PATH = $(abspath $(LLVM_BUILDDIR))/lib/liblibclang.a
 
 else ifeq ($(shell uname -s),Darwin)
     MD5SUM = md5
-    LIBCLANG_NAME = clang
+    LIBCLANG_PATH = $(abspath $(LLVM_BUILDDIR))/lib/libclang.a
 else ifeq ($(shell uname -s),FreeBSD)
     MD5SUM = md5
-    LIBCLANG_NAME = clang
+    LIBCLANG_PATH = $(abspath $(LLVM_BUILDDIR))/lib/libclang.a
     START_GROUP = -Wl,--start-group
     END_GROUP = -Wl,--end-group
 else
-    LIBCLANG_NAME = clang
+    LIBCLANG_PATH = $(abspath $(LLVM_BUILDDIR))/lib/libclang.a
     START_GROUP = -Wl,--start-group
     END_GROUP = -Wl,--end-group
 endif
 
-# Libraries that should be linked in for the statically linked Clang.
-CLANG_LIB_NAMES = clangAnalysis clangARCMigrate clangAST clangASTMatchers clangBasic clangCodeGen clangCrossTU clangDriver clangDynamicASTMatchers clangEdit clangFormat clangFrontend clangFrontendTool clangHandleCXX clangHandleLLVM clangIndex clangLex clangParse clangRewrite clangRewriteFrontend clangSema clangSerialization clangStaticAnalyzerCheckers clangStaticAnalyzerCore clangStaticAnalyzerFrontend clangTooling clangToolingASTDiff clangToolingCore clangToolingInclusions
-CLANG_LIBS = $(START_GROUP) $(addprefix -l,$(CLANG_LIB_NAMES)) $(END_GROUP) -lstdc++
+CLANG_LIBS = $(START_GROUP) -lclangAnalysis -lclangARCMigrate -lclangAST -lclangASTMatchers -lclangBasic -lclangCodeGen -lclangCrossTU -lclangDriver -lclangDynamicASTMatchers -lclangEdit -lclangFormat -lclangFrontend -lclangFrontendTool -lclangHandleCXX -lclangHandleLLVM -lclangIndex -lclangLex -lclangParse -lclangRewrite -lclangRewriteFrontend -lclangSema -lclangSerialization -lclangStaticAnalyzerCheckers -lclangStaticAnalyzerCore -lclangStaticAnalyzerFrontend -lclangTooling -lclangToolingASTDiff -lclangToolingCore -lclangToolingInclusions $(END_GROUP) -lstdc++
 
-# Libraries that should be linked in for the statically linked LLD.
-LLD_LIB_NAMES = lldCOFF lldCommon lldCore lldDriver lldELF lldMachO lldMinGW lldReaderWriter lldWasm lldYAML
-LLD_LIBS = $(START_GROUP) $(addprefix -l,$(LLD_LIB_NAMES)) $(END_GROUP)
+LLD_LIBS = $(START_GROUP) -llldCOFF -llldCommon -llldCore -llldDriver -llldELF -llldMachO -llldMinGW -llldReaderWriter -llldWasm -llldYAML $(END_GROUP)
 
-# Other libraries that are needed to link TinyGo.
-EXTRA_LIB_NAMES = LLVMInterpreter
-
-# These build targets appear to be the only ones necessary to build all TinyGo
-# dependencies. Only building a subset significantly speeds up rebuilding LLVM.
-# The Makefile rules convert a name like lldELF to lib/liblldELF.a to match the
-# library path (for ninja).
-# This list also includes a few tools that are necessary as part of the full
-# TinyGo build.
-NINJA_BUILD_TARGETS = clang llvm-config llvm-ar llvm-nm $(addprefix lib/lib,$(addsuffix .a,$(LIBCLANG_NAME) $(CLANG_LIB_NAMES) $(LLD_LIB_NAMES) $(EXTRA_LIB_NAMES)))
 
 # For static linking.
 ifneq ("$(wildcard $(LLVM_BUILDDIR)/bin/llvm-config*)","")
     CGO_CPPFLAGS+=$(shell $(LLVM_BUILDDIR)/bin/llvm-config --cppflags) -I$(abspath $(LLVM_BUILDDIR))/tools/clang/include -I$(abspath $(CLANG_SRC))/include -I$(abspath $(LLD_SRC))/include
     CGO_CXXFLAGS=-std=c++14
-    CGO_LDFLAGS+=$(abspath $(LLVM_BUILDDIR))/lib/lib$(LIBCLANG_NAME).a -L$(abspath $(LLVM_BUILDDIR)/lib) $(CLANG_LIBS) $(LLD_LIBS) $(shell $(LLVM_BUILDDIR)/bin/llvm-config --ldflags --libs --system-libs $(LLVM_COMPONENTS)) -lstdc++ $(CGO_LDFLAGS_EXTRA)
+    CGO_LDFLAGS+=$(LIBCLANG_PATH) -L$(abspath $(LLVM_BUILDDIR)/lib) $(CLANG_LIBS) $(LLD_LIBS) $(shell $(LLVM_BUILDDIR)/bin/llvm-config --ldflags --libs --system-libs $(LLVM_COMPONENTS)) -lstdc++ $(CGO_LDFLAGS_EXTRA)
 endif
 
 
 clean:
 	@rm -rf build
 
-FMT_PATHS = ./*.go builder cgo compiler interp loader src/device/arm src/examples src/machine src/os src/reflect src/runtime src/sync src/syscall src/internal/reflectlite transform
+FMT_PATHS = ./*.go builder cgo compiler interp ir loader src/device/arm src/examples src/machine src/os src/reflect src/runtime src/sync src/syscall src/internal/reflectlite transform
 fmt:
 	@gofmt -l -w $(FMT_PATHS)
 fmt-check:
@@ -156,11 +142,11 @@ llvm-source: $(LLVM_PROJECTDIR)/README.md
 # Configure LLVM.
 TINYGO_SOURCE_DIR=$(shell pwd)
 $(LLVM_BUILDDIR)/build.ninja: llvm-source
-	mkdir -p $(LLVM_BUILDDIR); cd $(LLVM_BUILDDIR); cmake -G Ninja $(TINYGO_SOURCE_DIR)/$(LLVM_PROJECTDIR)/llvm "-DLLVM_TARGETS_TO_BUILD=X86;ARM;AArch64;RISCV;WebAssembly" "-DLLVM_EXPERIMENTAL_TARGETS_TO_BUILD=AVR;Xtensa" -DCMAKE_BUILD_TYPE=Release -DLIBCLANG_BUILD_STATIC=ON -DLLVM_ENABLE_TERMINFO=OFF -DLLVM_ENABLE_ZLIB=OFF -DLLVM_ENABLE_LIBEDIT=OFF -DLLVM_ENABLE_Z3_SOLVER=OFF -DLLVM_ENABLE_OCAMLDOC=OFF -DLLVM_ENABLE_LIBXML2=OFF -DLLVM_ENABLE_PROJECTS="clang;lld" -DLLVM_TOOL_CLANG_TOOLS_EXTRA_BUILD=OFF $(LLVM_OPTION)
+	mkdir -p $(LLVM_BUILDDIR); cd $(LLVM_BUILDDIR); cmake -G Ninja $(TINYGO_SOURCE_DIR)/$(LLVM_PROJECTDIR)/llvm "-DLLVM_TARGETS_TO_BUILD=X86;ARM;AArch64;RISCV;WebAssembly" "-DLLVM_EXPERIMENTAL_TARGETS_TO_BUILD=AVR;Xtensa" -DCMAKE_BUILD_TYPE=Release -DLIBCLANG_BUILD_STATIC=ON -DLLVM_ENABLE_TERMINFO=OFF -DLLVM_ENABLE_ZLIB=OFF -DLLVM_ENABLE_LIBEDIT=OFF -DLLVM_ENABLE_Z3_SOLVER=OFF -DLLVM_ENABLE_OCAMLDOC=OFF -DLLVM_ENABLE_PROJECTS="clang;lld" -DLLVM_TOOL_CLANG_TOOLS_EXTRA_BUILD=OFF $(LLVM_OPTION)
 
 # Build LLVM.
 $(LLVM_BUILDDIR): $(LLVM_BUILDDIR)/build.ninja
-	cd $(LLVM_BUILDDIR); ninja $(NINJA_BUILD_TARGETS)
+	cd $(LLVM_BUILDDIR); ninja
 
 
 # Build wasi-libc sysroot
@@ -341,8 +327,6 @@ smoketest:
 	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=nucleo-f722ze       examples/blinky1
 	@$(MD5SUM) test.hex
-	$(TINYGO) build -size short -o test.hex -target=nucleo-l552ze       examples/blinky1
-	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=p1am-100            examples/blinky1
 	@$(MD5SUM) test.hex
 	# test pwm
@@ -391,8 +375,6 @@ endif
 	@$(MD5SUM) test.hex
 	$(TINYGO) build             -o test.nro -target=nintendoswitch      examples/serial
 	@$(MD5SUM) test.nro
-	$(TINYGO) build -size short -o test.hex -target=pca10040 -opt=0     ./testdata/stdlib.go
-	@$(MD5SUM) test.hex
 
 wasmtest:
 	$(GO) test ./tests/wasm

README.md

@@ -43,11 +43,11 @@ See the [getting started instructions](https://tinygo.org/getting-started/) for
 
 You can compile TinyGo programs for microcontrollers, WebAssembly and Linux.
 
-The following 55 microcontroller boards are currently supported:
+The following 44 microcontroller boards are currently supported:
 
 * [Adafruit Circuit Playground Bluefruit](https://www.adafruit.com/product/4333)
 * [Adafruit Circuit Playground Express](https://www.adafruit.com/product/3333)
-* [Adafruit CLUE](https://www.adafruit.com/product/4500)
+* [Adafruit CLUE Alpha](https://www.adafruit.com/product/4500)
 * [Adafruit Feather M0](https://www.adafruit.com/product/2772)
 * [Adafruit Feather M4](https://www.adafruit.com/product/3857)
 * [Adafruit Feather nRF52840 Express](https://www.adafruit.com/product/4062)
@@ -55,29 +55,22 @@ The following 55 microcontroller boards are currently supported:
 * [Adafruit ItsyBitsy M0](https://www.adafruit.com/product/3727)
 * [Adafruit ItsyBitsy M4](https://www.adafruit.com/product/3800)
 * [Adafruit ItsyBitsy nRF52840](https://www.adafruit.com/product/4481)
-* [Adafruit Matrix Portal M4](https://www.adafruit.com/product/4745)
 * [Adafruit Metro M4 Express Airlift](https://www.adafruit.com/product/4000)
 * [Adafruit PyBadge](https://www.adafruit.com/product/4200)
 * [Adafruit PyGamer](https://www.adafruit.com/product/4242)
 * [Adafruit PyPortal](https://www.adafruit.com/product/4116)
-* [Adafruit QT Py](https://www.adafruit.com/product/4600)
 * [Adafruit Trinket M0](https://www.adafruit.com/product/3500)
 * [Arduino Mega 2560](https://store.arduino.cc/arduino-mega-2560-rev3)
-* [Arduino MKR1000](https://store.arduino.cc/arduino-mkr1000-wifi)
 * [Arduino Nano](https://store.arduino.cc/arduino-nano)
 * [Arduino Nano33 IoT](https://store.arduino.cc/nano-33-iot)
 * [Arduino Uno](https://store.arduino.cc/arduino-uno-rev3)
 * [Arduino Zero](https://store.arduino.cc/usa/arduino-zero)
 * [BBC micro:bit](https://microbit.org/)
-* [BBC micro:bit v2](https://microbit.org/new-microbit/)
 * [Digispark](http://digistump.com/products/1)
-* [Dragino LoRaWAN GPS Tracker LGT-92](http://www.dragino.com/products/lora-lorawan-end-node/item/142-lgt-92.html)
 * [ESP32](https://www.espressif.com/en/products/socs/esp32)
 * [ESP8266](https://www.espressif.com/en/products/socs/esp8266)
 * [Game Boy Advance](https://en.wikipedia.org/wiki/Game_Boy_Advance)
 * [Makerdiary nRF52840-MDK](https://wiki.makerdiary.com/nrf52840-mdk/)
-* [Makerdiary nRF52840-MDK USB Dongle](https://wiki.makerdiary.com/nrf52840-mdk-usb-dongle/)
-* [nice!nano](https://docs.nicekeyboards.com/#/nice!nano/)
 * [Nintendo Switch](https://www.nintendo.com/switch/)
 * [Nordic Semiconductor PCA10031](https://www.nordicsemi.com/eng/Products/nRF51-Dongle)
 * [Nordic Semiconductor PCA10040](https://www.nordicsemi.com/eng/Products/Bluetooth-low-energy/nRF52-DK)
@@ -88,15 +81,11 @@ The following 55 microcontroller boards are currently supported:
 * [Phytec reel board](https://www.phytec.eu/product-eu/internet-of-things/reelboard/)
 * [PineTime DevKit](https://www.pine64.org/pinetime/)
 * [PJRC Teensy 3.6](https://www.pjrc.com/store/teensy36.html)
-* [PJRC Teensy 4.0](https://www.pjrc.com/store/teensy40.html)
-* [ProductivityOpen P1AM-100](https://facts-engineering.github.io/modules/P1AM-100/P1AM-100.html)
 * [Seeed Wio Terminal](https://www.seeedstudio.com/Wio-Terminal-p-4509.html)
 * [Seeed Seeeduino XIAO](https://www.seeedstudio.com/Seeeduino-XIAO-Arduino-Microcontroller-SAMD21-Cortex-M0+-p-4426.html)
 * [Seeed Sipeed MAix BiT](https://www.seeedstudio.com/Sipeed-MAix-BiT-for-RISC-V-AI-IoT-p-2872.html)
 * [SiFIve HiFive1](https://www.sifive.com/boards/hifive1)
-* [ST Micro "Nucleo" F103RB](https://www.st.com/en/evaluation-tools/nucleo-f103rb.html)
-* [ST Micro "Nucleo" F722ZE](https://www.st.com/en/evaluation-tools/nucleo-f722ze.html)
-* [ST Micro "Nucleo" L552ZE](https://www.st.com/en/evaluation-tools/nucleo-l552ze-q.html)
+* [ST Micro "Nucleo F103RB"](https://www.st.com/en/evaluation-tools/nucleo-f103rb.html)
 * [ST Micro STM32F103XX "Bluepill"](https://stm32-base.org/boards/STM32F103C8T6-Blue-Pill)
 * [ST Micro STM32F407 "Discovery"](https://www.st.com/en/evaluation-tools/stm32f4discovery.html)
 * [X9 Pro smartwatch](https://github.com/curtpw/nRF5x-device-reverse-engineering/tree/master/X9-nrf52832-activity-tracker/)

azure-pipelines.yml

@@ -12,7 +12,7 @@ jobs:
   steps:
     - task: GoTool@0
       inputs:
-        version: '1.16'
+        version: '1.15'
     - checkout: self
       fetchDepth: 1
     - task: Cache@2
@@ -24,11 +24,15 @@ jobs:
       displayName: Download LLVM source
       inputs:
         targetType: inline
-        script: make llvm-source
+        script: |
+          make llvm-source
+          # Workaround for bad symlinks:
+          # https://github.com/microsoft/azure-pipelines-tasks/issues/13418
+          rm -f llvm-project/libcxx/test/std/input.output/filesystems/Inputs/static_test_env/bad_symlink
     - task: CacheBeta@0
       displayName: Cache LLVM build
       inputs:
-        key: llvm-build-11-windows-v4
+        key: llvm-build-11-windows-v3
         path: llvm-build
     - task: Bash@3
       displayName: Build LLVM
@@ -52,7 +56,7 @@ jobs:
     - task: CacheBeta@0
       displayName: Cache wasi-libc sysroot
       inputs:
-        key: wasi-libc-sysroot-v4
+        key: wasi-libc-sysroot-v3
         path: lib/wasi-libc/sysroot
     - task: Bash@3
       displayName: Build wasi-libc

builder/build.go

@@ -4,18 +4,14 @@
 package builder
 
 import (
-	"crypto/sha512"
 	"debug/elf"
 	"encoding/binary"
-	"encoding/hex"
-	"encoding/json"
 	"errors"
 	"fmt"
 	"go/types"
 	"io/ioutil"
 	"os"
 	"path/filepath"
-	"runtime"
 	"sort"
 	"strconv"
 	"strings"
@@ -42,26 +38,6 @@ type BuildResult struct {
 	MainDir string
 }
 
-// packageAction is the struct that is serialized to JSON and hashed, to work as
-// a cache key of compiled packages. It should contain all the information that
-// goes into a compiled package to avoid using stale data.
-//
-// Right now it's still important to include a hash of every import, because a
-// dependency might have a public constant that this package uses and thus this
-// package will need to be recompiled if that constant changes. In the future,
-// the type data should be serialized to disk which can then be used as cache
-// key, avoiding the need for recompiling all dependencies when only the
-// implementation of an imported package changes.
-type packageAction struct {
-	ImportPath      string
-	CompilerVersion int // compiler.Version
-	LLVMVersion     string
-	Config          *compiler.Config
-	CFlags          []string
-	FileHashes      map[string]string // hash of every file that's part of the package
-	Imports         map[string]string // map from imported package to action ID hash
-}
-
 // Build performs a single package to executable Go build. It takes in a package
 // name, an output path, and set of compile options and from that it manages the
 // whole compilation process.
@@ -69,34 +45,10 @@ type packageAction struct {
 // The error value may be of type *MultiError. Callers will likely want to check
 // for this case and print such errors individually.
 func Build(pkgName, outpath string, config *compileopts.Config, action func(BuildResult) error) error {
-	// Create a temporary directory for intermediary files.
-	dir, err := ioutil.TempDir("", "tinygo")
-	if err != nil {
-		return err
-	}
-	defer os.RemoveAll(dir)
-
-	compilerConfig := &compiler.Config{
-		Triple:          config.Triple(),
-		CPU:             config.CPU(),
-		Features:        config.Features(),
-		GOOS:            config.GOOS(),
-		GOARCH:          config.GOARCH(),
-		CodeModel:       config.CodeModel(),
-		RelocationModel: config.RelocationModel(),
-
-		Scheduler:          config.Scheduler(),
-		FuncImplementation: config.FuncImplementation(),
-		AutomaticStackSize: config.AutomaticStackSize(),
-		DefaultStackSize:   config.Target.DefaultStackSize,
-		NeedsStackObjects:  config.NeedsStackObjects(),
-		Debug:              config.Debug(),
-	}
-
 	// Load the target machine, which is the LLVM object that contains all
 	// details of a target (alignment restrictions, pointer size, default
 	// address spaces, etc).
-	machine, err := compiler.NewTargetMachine(compilerConfig)
+	machine, err := compiler.NewTargetMachine(config)
 	if err != nil {
 		return err
 	}
@@ -113,465 +65,21 @@ func Build(pkgName, outpath string, config *compileopts.Config, action func(Buil
 		return err
 	}
 
-	// The slice of jobs that orchestrates most of the build.
-	// This is somewhat like an in-memory Makefile with each job being a
-	// Makefile target.
-	var jobs []*compileJob
-
-	// Create the *ssa.Program. This does not yet build the entire SSA of the
-	// program so it's pretty fast and doesn't need to be parallelized.
-	program := lprogram.LoadSSA()
-
-	// Add jobs to compile each package.
-	// Packages that have a cache hit will not be compiled again.
-	var packageJobs []*compileJob
-	packageBitcodePaths := make(map[string]string)
-	packageActionIDs := make(map[string]string)
-	for _, pkg := range lprogram.Sorted() {
-		pkg := pkg // necessary to avoid a race condition
-
-		// Create a cache key: a hash from the action ID below that contains all
-		// the parameters for the build.
-		actionID := packageAction{
-			ImportPath:      pkg.ImportPath,
-			CompilerVersion: compiler.Version,
-			LLVMVersion:     llvm.Version,
-			Config:          compilerConfig,
-			CFlags:          pkg.CFlags,
-			FileHashes:      make(map[string]string, len(pkg.FileHashes)),
-			Imports:         make(map[string]string, len(pkg.Pkg.Imports())),
-		}
-		for filePath, hash := range pkg.FileHashes {
-			actionID.FileHashes[filePath] = hex.EncodeToString(hash)
-		}
-		for _, imported := range pkg.Pkg.Imports() {
-			hash, ok := packageActionIDs[imported.Path()]
-			if !ok {
-				return fmt.Errorf("package %s imports %s but couldn't find dependency", pkg.ImportPath, imported.Path())
-			}
-			actionID.Imports[imported.Path()] = hash
-		}
-		buf, err := json.Marshal(actionID)
-		if err != nil {
-			panic(err) // shouldn't happen
-		}
-		hash := sha512.Sum512_224(buf)
-		packageActionIDs[pkg.ImportPath] = hex.EncodeToString(hash[:])
-
-		// Determine the path of the bitcode file (which is a serialized version
-		// of a LLVM module).
-		cacheDir := goenv.Get("GOCACHE")
-		if cacheDir == "off" {
-			// Use temporary build directory instead, effectively disabling the
-			// build cache.
-			cacheDir = dir
-		}
-		bitcodePath := filepath.Join(cacheDir, "pkg-"+hex.EncodeToString(hash[:])+".bc")
-		packageBitcodePaths[pkg.ImportPath] = bitcodePath
-
-		// Check whether this package has been compiled before, and if so don't
-		// compile it again.
-		if _, err := os.Stat(bitcodePath); err == nil {
-			// Already cached, don't recreate this package.
-			continue
-		}
-
-		// The package has not yet been compiled, so create a job to do so.
-		job := &compileJob{
-			description: "compile package " + pkg.ImportPath,
-			run: func() error {
-				// Compile AST to IR. The compiler.CompilePackage function will
-				// build the SSA as needed.
-				mod, errs := compiler.CompilePackage(pkg.ImportPath, pkg, program.Package(pkg.Pkg), machine, compilerConfig, config.DumpSSA())
-				if errs != nil {
-					return newMultiError(errs)
-				}
-				if err := llvm.VerifyModule(mod, llvm.PrintMessageAction); err != nil {
-					return errors.New("verification error after compiling package " + pkg.ImportPath)
-				}
-
-				// Serialize the LLVM module as a bitcode file.
-				// Write to a temporary path that is renamed to the destination
-				// file to avoid race conditions with other TinyGo invocatiosn
-				// that might also be compiling this package at the same time.
-				f, err := ioutil.TempFile(filepath.Dir(bitcodePath), filepath.Base(bitcodePath))
-				if err != nil {
-					return err
-				}
-				if runtime.GOOS == "windows" {
-					// Work around a problem on Windows.
-					// For some reason, WriteBitcodeToFile causes TinyGo to
-					// exit with the following message:
-					//   LLVM ERROR: IO failure on output stream: Bad file descriptor
-					buf := llvm.WriteBitcodeToMemoryBuffer(mod)
-					defer buf.Dispose()
-					_, err = f.Write(buf.Bytes())
-				} else {
-					// Otherwise, write bitcode directly to the file (probably
-					// faster).
-					err = llvm.WriteBitcodeToFile(mod, f)
-				}
-				if err != nil {
-					// WriteBitcodeToFile doesn't produce a useful error on its
-					// own, so create a somewhat useful error message here.
-					return fmt.Errorf("failed to write bitcode for package %s to file %s", pkg.ImportPath, bitcodePath)
-				}
-				err = f.Close()
-				if err != nil {
-					return err
-				}
-				return os.Rename(f.Name(), bitcodePath)
-			},
-		}
-		jobs = append(jobs, job)
-		packageJobs = append(packageJobs, job)
+	// Compile AST to IR.
+	mod, errs := compiler.CompileProgram(pkgName, lprogram, machine, config)
+	if errs != nil {
+		return newMultiError(errs)
 	}
 
-	// Add job that links and optimizes all packages together.
-	var mod llvm.Module
-	var stackSizeLoads []string
-	programJob := &compileJob{
-		description:  "link+optimize packages (LTO)",
-		dependencies: packageJobs,
-		run: func() error {
-			// Load and link all the bitcode files. This does not yet optimize
-			// anything, it only links the bitcode files together.
-			ctx := llvm.NewContext()
-			mod = ctx.NewModule("")
-			for _, pkg := range lprogram.Sorted() {
-				pkgMod, err := ctx.ParseBitcodeFile(packageBitcodePaths[pkg.ImportPath])
-				if err != nil {
-					return fmt.Errorf("failed to load bitcode file: %w", err)
-				}
-				err = llvm.LinkModules(mod, pkgMod)
-				if err != nil {
-					return fmt.Errorf("failed to link module: %w", err)
-				}
-			}
-
-			// Create runtime.initAll function that calls the runtime
-			// initializer of each package.
-			llvmInitFn := mod.NamedFunction("runtime.initAll")
-			llvmInitFn.SetLinkage(llvm.InternalLinkage)
-			llvmInitFn.SetUnnamedAddr(true)
-			llvmInitFn.Param(0).SetName("context")
-			llvmInitFn.Param(1).SetName("parentHandle")
-			block := mod.Context().AddBasicBlock(llvmInitFn, "entry")
-			irbuilder := mod.Context().NewBuilder()
-			defer irbuilder.Dispose()
-			irbuilder.SetInsertPointAtEnd(block)
-			i8ptrType := llvm.PointerType(mod.Context().Int8Type(), 0)
-			for _, pkg := range lprogram.Sorted() {
-				pkgInit := mod.NamedFunction(pkg.Pkg.Path() + ".init")
-				if pkgInit.IsNil() {
-					panic("init not found for " + pkg.Pkg.Path())
-				}
-				irbuilder.CreateCall(pkgInit, []llvm.Value{llvm.Undef(i8ptrType), llvm.Undef(i8ptrType)}, "")
-			}
-			irbuilder.CreateRetVoid()
-
-			// After linking, functions should (as far as possible) be set to
-			// private linkage or internal linkage. The compiler package marks
-			// non-exported functions by setting the visibility to hidden or
-			// (for thunks) to linkonce_odr linkage. Change the linkage here to
-			// internal to benefit much more from interprocedural optimizations.
-			for fn := mod.FirstFunction(); !fn.IsNil(); fn = llvm.NextFunction(fn) {
-				if fn.Visibility() == llvm.HiddenVisibility {
-					fn.SetVisibility(llvm.DefaultVisibility)
-					fn.SetLinkage(llvm.InternalLinkage)
-				} else if fn.Linkage() == llvm.LinkOnceODRLinkage {
-					fn.SetLinkage(llvm.InternalLinkage)
-				}
-			}
-
-			// Do the same for globals.
-			for global := mod.FirstGlobal(); !global.IsNil(); global = llvm.NextGlobal(global) {
-				if global.Visibility() == llvm.HiddenVisibility {
-					global.SetVisibility(llvm.DefaultVisibility)
-					global.SetLinkage(llvm.InternalLinkage)
-				} else if global.Linkage() == llvm.LinkOnceODRLinkage {
-					global.SetLinkage(llvm.InternalLinkage)
-				}
-			}
-
-			if config.Options.PrintIR {
-				fmt.Println("; Generated LLVM IR:")
-				fmt.Println(mod.String())
-			}
-
-			// Run all optimization passes, which are much more effective now
-			// that the optimizer can see the whole program at once.
-			err := optimizeProgram(mod, config)
-			if err != nil {
-				return err
-			}
-
-			// Make sure stack sizes are loaded from a separate section so they can be
-			// modified after linking.
-			if config.AutomaticStackSize() {
-				stackSizeLoads = transform.CreateStackSizeLoads(mod, config)
-			}
-			return nil
-		},
+	if config.Options.PrintIR {
+		fmt.Println("; Generated LLVM IR:")
+		fmt.Println(mod.String())
 	}
-	jobs = append(jobs, programJob)
-
-	// Check whether we only need to create an object file.
-	// If so, we don't need to link anything and will be finished quickly.
-	outext := filepath.Ext(outpath)
-	if outext == ".o" || outext == ".bc" || outext == ".ll" {
-		// Run jobs to produce the LLVM module.
-		err := runJobs(jobs)
-		if err != nil {
-			return err
-		}
-		// Generate output.
-		switch outext {
-		case ".o":
-			llvmBuf, err := machine.EmitToMemoryBuffer(mod, llvm.ObjectFile)
-			if err != nil {
-				return err
-			}
-			return ioutil.WriteFile(outpath, llvmBuf.Bytes(), 0666)
-		case ".bc":
-			data := llvm.WriteBitcodeToMemoryBuffer(mod).Bytes()
-			return ioutil.WriteFile(outpath, data, 0666)
-		case ".ll":
-			data := []byte(mod.String())
-			return ioutil.WriteFile(outpath, data, 0666)
-		default:
-			panic("unreachable")
-		}
+	if err := llvm.VerifyModule(mod, llvm.PrintMessageAction); err != nil {
+		return errors.New("verification error after IR construction")
 	}
 
-	// Act as a compiler driver, as we need to produce a complete executable.
-	// First add all jobs necessary to build this object file, then afterwards
-	// run all jobs in parallel as far as possible.
-
-	// Add job to write the output object file.
-	objfile := filepath.Join(dir, "main.o")
-	outputObjectFileJob := &compileJob{
-		description:  "generate output file",
-		dependencies: []*compileJob{programJob},
-		run: func() error {
-			llvmBuf, err := machine.EmitToMemoryBuffer(mod, llvm.ObjectFile)
-			if err != nil {
-				return err
-			}
-			return ioutil.WriteFile(objfile, llvmBuf.Bytes(), 0666)
-		},
-	}
-	jobs = append(jobs, outputObjectFileJob)
-
-	// Prepare link command.
-	linkerDependencies := []*compileJob{outputObjectFileJob}
-	executable := filepath.Join(dir, "main")
-	tmppath := executable // final file
-	ldflags := append(config.LDFlags(), "-o", executable, objfile)
-
-	// Add compiler-rt dependency if needed. Usually this is a simple load from
-	// a cache.
-	if config.Target.RTLib == "compiler-rt" {
-		path, job, err := CompilerRT.load(config.Triple(), config.CPU(), dir)
-		if err != nil {
-			return err
-		}
-		if job != nil {
-			// The library was not loaded from cache so needs to be compiled
-			// (and then stored in the cache).
-			jobs = append(jobs, job.dependencies...)
-			jobs = append(jobs, job)
-			linkerDependencies = append(linkerDependencies, job)
-		}
-		ldflags = append(ldflags, path)
-	}
-
-	// Add libc dependency if needed.
-	root := goenv.Get("TINYGOROOT")
-	switch config.Target.Libc {
-	case "picolibc":
-		path, job, err := Picolibc.load(config.Triple(), config.CPU(), dir)
-		if err != nil {
-			return err
-		}
-		if job != nil {
-			// The library needs to be compiled (cache miss).
-			jobs = append(jobs, job.dependencies...)
-			jobs = append(jobs, job)
-			linkerDependencies = append(linkerDependencies, job)
-		}
-		ldflags = append(ldflags, path)
-	case "wasi-libc":
-		path := filepath.Join(root, "lib/wasi-libc/sysroot/lib/wasm32-wasi/libc.a")
-		if _, err := os.Stat(path); os.IsNotExist(err) {
-			return errors.New("could not find wasi-libc, perhaps you need to run `make wasi-libc`?")
-		}
-		ldflags = append(ldflags, path)
-	case "":
-		// no library specified, so nothing to do
-	default:
-		return fmt.Errorf("unknown libc: %s", config.Target.Libc)
-	}
-
-	// Add jobs to compile extra files. These files are in C or assembly and
-	// contain things like the interrupt vector table and low level operations
-	// such as stack switching.
-	for i, path := range config.ExtraFiles() {
-		abspath := filepath.Join(root, path)
-		outpath := filepath.Join(dir, "extra-"+strconv.Itoa(i)+"-"+filepath.Base(path)+".o")
-		job := &compileJob{
-			description: "compile extra file " + path,
-			run: func() error {
-				err := runCCompiler(config.Target.Compiler, append(config.CFlags(), "-c", "-o", outpath, abspath)...)
-				if err != nil {
-					return &commandError{"failed to build", path, err}
-				}
-				return nil
-			},
-		}
-		jobs = append(jobs, job)
-		linkerDependencies = append(linkerDependencies, job)
-		ldflags = append(ldflags, outpath)
-	}
-
-	// Add jobs to compile C files in all packages. This is part of CGo.
-	// TODO: do this as part of building the package to be able to link the
-	// bitcode files together.
-	for i, pkg := range lprogram.Sorted() {
-		for j, filename := range pkg.CFiles {
-			file := filepath.Join(pkg.Dir, filename)
-			outpath := filepath.Join(dir, "pkg"+strconv.Itoa(i)+"."+strconv.Itoa(j)+"-"+filepath.Base(file)+".o")
-			job := &compileJob{
-				description: "compile CGo file " + file,
-				run: func() error {
-					err := runCCompiler(config.Target.Compiler, append(config.CFlags(), "-c", "-o", outpath, file)...)
-					if err != nil {
-						return &commandError{"failed to build", file, err}
-					}
-					return nil
-				},
-			}
-			jobs = append(jobs, job)
-			linkerDependencies = append(linkerDependencies, job)
-			ldflags = append(ldflags, outpath)
-		}
-	}
-
-	// Linker flags from CGo lines:
-	//     #cgo LDFLAGS: foo
-	if len(lprogram.LDFlags) > 0 {
-		ldflags = append(ldflags, lprogram.LDFlags...)
-	}
-
-	// Create a linker job, which links all object files together and does some
-	// extra stuff that can only be done after linking.
-	jobs = append(jobs, &compileJob{
-		description:  "link",
-		dependencies: linkerDependencies,
-		run: func() error {
-			err = link(config.Target.Linker, ldflags...)
-			if err != nil {
-				return &commandError{"failed to link", executable, err}
-			}
-
-			var calculatedStacks []string
-			var stackSizes map[string]functionStackSize
-			if config.Options.PrintStacks || config.AutomaticStackSize() {
-				// Try to determine stack sizes at compile time.
-				// Don't do this by default as it usually doesn't work on
-				// unsupported architectures.
-				calculatedStacks, stackSizes, err = determineStackSizes(mod, executable)
-				if err != nil {
-					return err
-				}
-			}
-			if config.AutomaticStackSize() {
-				// Modify the .tinygo_stacksizes section that contains a stack size
-				// for each goroutine.
-				err = modifyStackSizes(executable, stackSizeLoads, stackSizes)
-				if err != nil {
-					return fmt.Errorf("could not modify stack sizes: %w", err)
-				}
-			}
-
-			if config.Options.PrintSizes == "short" || config.Options.PrintSizes == "full" {
-				sizes, err := loadProgramSize(executable)
-				if err != nil {
-					return err
-				}
-				if config.Options.PrintSizes == "short" {
-					fmt.Printf("   code    data     bss |   flash     ram\n")
-					fmt.Printf("%7d %7d %7d | %7d %7d\n", sizes.Code, sizes.Data, sizes.BSS, sizes.Code+sizes.Data, sizes.Data+sizes.BSS)
-				} else {
-					fmt.Printf("   code  rodata    data     bss |   flash     ram | package\n")
-					for _, name := range sizes.sortedPackageNames() {
-						pkgSize := sizes.Packages[name]
-						fmt.Printf("%7d %7d %7d %7d | %7d %7d | %s\n", pkgSize.Code, pkgSize.ROData, pkgSize.Data, pkgSize.BSS, pkgSize.Flash(), pkgSize.RAM(), name)
-					}
-					fmt.Printf("%7d %7d %7d %7d | %7d %7d | (sum)\n", sizes.Sum.Code, sizes.Sum.ROData, sizes.Sum.Data, sizes.Sum.BSS, sizes.Sum.Flash(), sizes.Sum.RAM())
-					fmt.Printf("%7d       - %7d %7d | %7d %7d | (all)\n", sizes.Code, sizes.Data, sizes.BSS, sizes.Code+sizes.Data, sizes.Data+sizes.BSS)
-				}
-			}
-
-			// Print goroutine stack sizes, as far as possible.
-			if config.Options.PrintStacks {
-				printStacks(calculatedStacks, stackSizes)
-			}
-
-			return nil
-		},
-	})
-
-	// Run all jobs to compile and link the program.
-	// Do this now (instead of after elf-to-hex and similar conversions) as it
-	// is simpler and cannot be parallelized.
-	err = runJobs(jobs)
-	if err != nil {
-		return err
-	}
-
-	// Get an Intel .hex file or .bin file from the .elf file.
-	outputBinaryFormat := config.BinaryFormat(outext)
-	switch outputBinaryFormat {
-	case "elf":
-		// do nothing, file is already in ELF format
-	case "hex", "bin":
-		// Extract raw binary, either encoding it as a hex file or as a raw
-		// firmware file.
-		tmppath = filepath.Join(dir, "main"+outext)
-		err := objcopy(executable, tmppath, outputBinaryFormat)
-		if err != nil {
-			return err
-		}
-	case "uf2":
-		// Get UF2 from the .elf file.
-		tmppath = filepath.Join(dir, "main"+outext)
-		err := convertELFFileToUF2File(executable, tmppath, config.Target.UF2FamilyID)
-		if err != nil {
-			return err
-		}
-	case "esp32", "esp8266":
-		// Special format for the ESP family of chips (parsed by the ROM
-		// bootloader).
-		tmppath = filepath.Join(dir, "main"+outext)
-		err := makeESPFirmareImage(executable, tmppath, outputBinaryFormat)
-		if err != nil {
-			return err
-		}
-	default:
-		return fmt.Errorf("unknown output binary format: %s", outputBinaryFormat)
-	}
-	return action(BuildResult{
-		Binary:  tmppath,
-		MainDir: lprogram.MainPkg().Dir,
-	})
-}
-
-// optimizeProgram runs a series of optimizations and transformations that are
-// needed to convert a program to its final form. Some transformations are not
-// optional and must be run as the compiler expects them to run.
-func optimizeProgram(mod llvm.Module, config *compileopts.Config) error {
-	err := interp.Run(mod, config.DumpSSA())
+	err = interp.Run(mod, config.DumpSSA())
 	if err != nil {
 		return err
 	}
@@ -597,10 +105,17 @@ func optimizeProgram(mod llvm.Module, config *compileopts.Config) error {
 
 	// Optimization levels here are roughly the same as Clang, but probably not
 	// exactly.
-	var errs []error
+	errs = nil
 	switch config.Options.Opt {
-	case "none", "0":
-		errs = transform.Optimize(mod, config, 0, 0, 0) // -O0
+	/*
+		Currently, turning optimizations off causes compile failures.
+		We rely on the optimizer removing some dead symbols.
+		Avoid providing an option that does not work right now.
+		In the future once everything has been fixed we can re-enable this.
+
+		case "none", "0":
+			errs = transform.Optimize(mod, config, 0, 0, 0) // -O0
+	*/
 	case "1":
 		errs = transform.Optimize(mod, config, 1, 0, 0) // -O1
 	case "2":
@@ -610,7 +125,7 @@ func optimizeProgram(mod llvm.Module, config *compileopts.Config) error {
 	case "z":
 		errs = transform.Optimize(mod, config, 2, 2, 5) // -Oz, default
 	default:
-		return errors.New("unknown optimization level: -opt=" + config.Options.Opt)
+		errs = []error{errors.New("unknown optimization level: -opt=" + config.Options.Opt)}
 	}
 	if len(errs) > 0 {
 		return newMultiError(errs)
@@ -630,7 +145,189 @@ func optimizeProgram(mod llvm.Module, config *compileopts.Config) error {
 		transform.DisableTailCalls(mod)
 	}
 
-	return nil
+	// Make sure stack sizes are loaded from a separate section so they can be
+	// modified after linking.
+	var stackSizeLoads []string
+	if config.AutomaticStackSize() {
+		stackSizeLoads = transform.CreateStackSizeLoads(mod, config)
+	}
+
+	// Generate output.
+	outext := filepath.Ext(outpath)
+	switch outext {
+	case ".o":
+		llvmBuf, err := machine.EmitToMemoryBuffer(mod, llvm.ObjectFile)
+		if err != nil {
+			return err
+		}
+		return ioutil.WriteFile(outpath, llvmBuf.Bytes(), 0666)
+	case ".bc":
+		data := llvm.WriteBitcodeToMemoryBuffer(mod).Bytes()
+		return ioutil.WriteFile(outpath, data, 0666)
+	case ".ll":
+		data := []byte(mod.String())
+		return ioutil.WriteFile(outpath, data, 0666)
+	default:
+		// Act as a compiler driver.
+
+		// Create a temporary directory for intermediary files.
+		dir, err := ioutil.TempDir("", "tinygo")
+		if err != nil {
+			return err
+		}
+		defer os.RemoveAll(dir)
+
+		// Write the object file.
+		objfile := filepath.Join(dir, "main.o")
+		llvmBuf, err := machine.EmitToMemoryBuffer(mod, llvm.ObjectFile)
+		if err != nil {
+			return err
+		}
+		err = ioutil.WriteFile(objfile, llvmBuf.Bytes(), 0666)
+		if err != nil {
+			return err
+		}
+
+		// Prepare link command.
+		executable := filepath.Join(dir, "main")
+		tmppath := executable // final file
+		ldflags := append(config.LDFlags(), "-o", executable, objfile)
+
+		// Load builtins library from the cache, possibly compiling it on the
+		// fly.
+		if config.Target.RTLib == "compiler-rt" {
+			librt, err := CompilerRT.Load(config.Triple())
+			if err != nil {
+				return err
+			}
+			ldflags = append(ldflags, librt)
+		}
+
+		// Add libc.
+		if config.Target.Libc == "picolibc" {
+			libc, err := Picolibc.Load(config.Triple())
+			if err != nil {
+				return err
+			}
+			ldflags = append(ldflags, libc)
+		}
+
+		// Compile extra files.
+		root := goenv.Get("TINYGOROOT")
+		for i, path := range config.ExtraFiles() {
+			abspath := filepath.Join(root, path)
+			outpath := filepath.Join(dir, "extra-"+strconv.Itoa(i)+"-"+filepath.Base(path)+".o")
+			err := runCCompiler(config.Target.Compiler, append(config.CFlags(), "-c", "-o", outpath, abspath)...)
+			if err != nil {
+				return &commandError{"failed to build", path, err}
+			}
+			ldflags = append(ldflags, outpath)
+		}
+
+		// Compile C files in packages.
+		// Gather the list of (C) file paths that should be included in the build.
+		for i, pkg := range lprogram.Sorted() {
+			for j, filename := range pkg.CFiles {
+				file := filepath.Join(pkg.Dir, filename)
+				outpath := filepath.Join(dir, "pkg"+strconv.Itoa(i)+"."+strconv.Itoa(j)+"-"+filepath.Base(file)+".o")
+				err := runCCompiler(config.Target.Compiler, append(config.CFlags(), "-c", "-o", outpath, file)...)
+				if err != nil {
+					return &commandError{"failed to build", file, err}
+				}
+				ldflags = append(ldflags, outpath)
+			}
+		}
+
+		if len(lprogram.LDFlags) > 0 {
+			ldflags = append(ldflags, lprogram.LDFlags...)
+		}
+
+		// Link the object files together.
+		err = link(config.Target.Linker, ldflags...)
+		if err != nil {
+			return &commandError{"failed to link", executable, err}
+		}
+
+		var calculatedStacks []string
+		var stackSizes map[string]functionStackSize
+		if config.Options.PrintStacks || config.AutomaticStackSize() {
+			// Try to determine stack sizes at compile time.
+			// Don't do this by default as it usually doesn't work on
+			// unsupported architectures.
+			calculatedStacks, stackSizes, err = determineStackSizes(mod, executable)
+			if err != nil {
+				return err
+			}
+		}
+		if config.AutomaticStackSize() {
+			// Modify the .tinygo_stacksizes section that contains a stack size
+			// for each goroutine.
+			err = modifyStackSizes(executable, stackSizeLoads, stackSizes)
+			if err != nil {
+				return fmt.Errorf("could not modify stack sizes: %w", err)
+			}
+		}
+
+		if config.Options.PrintSizes == "short" || config.Options.PrintSizes == "full" {
+			sizes, err := loadProgramSize(executable)
+			if err != nil {
+				return err
+			}
+			if config.Options.PrintSizes == "short" {
+				fmt.Printf("   code    data     bss |   flash     ram\n")
+				fmt.Printf("%7d %7d %7d | %7d %7d\n", sizes.Code, sizes.Data, sizes.BSS, sizes.Code+sizes.Data, sizes.Data+sizes.BSS)
+			} else {
+				fmt.Printf("   code  rodata    data     bss |   flash     ram | package\n")
+				for _, name := range sizes.sortedPackageNames() {
+					pkgSize := sizes.Packages[name]
+					fmt.Printf("%7d %7d %7d %7d | %7d %7d | %s\n", pkgSize.Code, pkgSize.ROData, pkgSize.Data, pkgSize.BSS, pkgSize.Flash(), pkgSize.RAM(), name)
+				}
+				fmt.Printf("%7d %7d %7d %7d | %7d %7d | (sum)\n", sizes.Sum.Code, sizes.Sum.ROData, sizes.Sum.Data, sizes.Sum.BSS, sizes.Sum.Flash(), sizes.Sum.RAM())
+				fmt.Printf("%7d       - %7d %7d | %7d %7d | (all)\n", sizes.Code, sizes.Data, sizes.BSS, sizes.Code+sizes.Data, sizes.Data+sizes.BSS)
+			}
+		}
+
+		// Print goroutine stack sizes, as far as possible.
+		if config.Options.PrintStacks {
+			printStacks(calculatedStacks, stackSizes)
+		}
+
+		// Get an Intel .hex file or .bin file from the .elf file.
+		outputBinaryFormat := config.BinaryFormat(outext)
+		switch outputBinaryFormat {
+		case "elf":
+			// do nothing, file is already in ELF format
+		case "hex", "bin":
+			// Extract raw binary, either encoding it as a hex file or as a raw
+			// firmware file.
+			tmppath = filepath.Join(dir, "main"+outext)
+			err := objcopy(executable, tmppath, outputBinaryFormat)
+			if err != nil {
+				return err
+			}
+		case "uf2":
+			// Get UF2 from the .elf file.
+			tmppath = filepath.Join(dir, "main"+outext)
+			err := convertELFFileToUF2File(executable, tmppath, config.Target.UF2FamilyID)
+			if err != nil {
+				return err
+			}
+		case "esp32", "esp8266":
+			// Special format for the ESP family of chips (parsed by the ROM
+			// bootloader).
+			tmppath = filepath.Join(dir, "main"+outext)
+			err := makeESPFirmareImage(executable, tmppath, outputBinaryFormat)
+			if err != nil {
+				return err
+			}
+		default:
+			return fmt.Errorf("unknown output binary format: %s", outputBinaryFormat)
+		}
+		return action(BuildResult{
+			Binary:  tmppath,
+			MainDir: lprogram.MainPkg().Dir,
+		})
+	}
 }
 
 // functionStackSizes keeps stack size information about a single function

builder/buildcache.go

@@ -30,7 +30,10 @@ func cacheTimestamp(paths []string) (time.Time, error) {
 // Try to load a given file from the cache. Return "", nil if no cached file can
 // be found (or the file is stale), return the absolute path if there is a cache
 // and return an error on I/O errors.
-func cacheLoad(name string, sourceFiles []string) (string, error) {
+//
+// TODO: the configKey is currently ignored. It is supposed to be used as extra
+// data for the cache key, like the compiler version and arguments.
+func cacheLoad(name, configKey string, sourceFiles []string) (string, error) {
 	cachepath := filepath.Join(goenv.Get("GOCACHE"), name)
 	cacheStat, err := os.Stat(cachepath)
 	if os.IsNotExist(err) {
@@ -55,7 +58,9 @@ func cacheLoad(name string, sourceFiles []string) (string, error) {
 
 // Store the file located at tmppath in the cache with the given name. The
 // tmppath may or may not be gone afterwards.
-func cacheStore(tmppath, name string, sourceFiles []string) (string, error) {
+//
+// Note: the configKey is ignored, see cacheLoad.
+func cacheStore(tmppath, name, configKey string, sourceFiles []string) (string, error) {
 	// get the last modified time
 	if len(sourceFiles) == 0 {
 		panic("cache: no source files")
@@ -69,16 +74,24 @@ func cacheStore(tmppath, name string, sourceFiles []string) (string, error) {
 		return "", err
 	}
 	cachepath := filepath.Join(dir, name)
-	err = copyFile(tmppath, cachepath)
+	err = moveFile(tmppath, cachepath)
 	if err != nil {
 		return "", err
 	}
 	return cachepath, nil
 }
 
-// copyFile copies the given file from src to dst. It can copy over
-// a possibly already existing file at the destination.
-func copyFile(src, dst string) error {
+// moveFile renames the file from src to dst. If renaming doesn't work (for
+// example, the rename crosses a filesystem boundary), the file is copied and
+// the old file is removed.
+func moveFile(src, dst string) error {
+	err := os.Rename(src, dst)
+	if err == nil {
+		// Success!
+		return nil
+	}
+	// Failed to move, probably a different filesystem.
+	// Do a copy + remove.
 	inf, err := os.Open(src)
 	if err != nil {
 		return err

builder/config.go

@@ -25,8 +25,8 @@ func NewConfig(options *compileopts.Options) (*compileopts.Config, error) {
 	if err != nil {
 		return nil, fmt.Errorf("could not read version from GOROOT (%v): %v", goroot, err)
 	}
-	if major != 1 || minor < 13 || minor > 16 {
-		return nil, fmt.Errorf("requires go version 1.13 through 1.16, got go%d.%d", major, minor)
+	if major != 1 || minor < 11 || minor > 15 {
+		return nil, fmt.Errorf("requires go version 1.11 through 1.15, got go%d.%d", major, minor)
 	}
 	clangHeaderPath := getClangHeaderPath(goenv.Get("TINYGOROOT"))
 	return &compileopts.Config{

builder/jobs.go

@@ -1,160 +0,0 @@
-package builder
-
-// This file implements a job runner for the compiler, which runs jobs in
-// parallel while taking care of dependencies.
-
-import (
-	"fmt"
-	"runtime"
-	"time"
-)
-
-// Set to true to enable logging in the job runner. This may help to debug
-// concurrency or performance issues.
-const jobRunnerDebug = false
-
-type jobState uint8
-
-const (
-	jobStateQueued   jobState = iota // not yet running
-	jobStateRunning                  // running
-	jobStateFinished                 // finished running
-)
-
-// compileJob is a single compiler job, comparable to a single Makefile target.
-// It is used to orchestrate various compiler tasks that can be run in parallel
-// but that have dependencies and thus have limitations in how they can be run.
-type compileJob struct {
-	description  string // description, only used for logging
-	dependencies []*compileJob
-	run          func() error
-	state        jobState
-	err          error         // error if finished
-	duration     time.Duration // how long it took to run this job (only set after finishing)
-}
-
-// readyToRun returns whether this job is ready to run: it is itself not yet
-// started and all dependencies are finished.
-func (job *compileJob) readyToRun() bool {
-	if job.state != jobStateQueued {
-		// Already running or finished, so shouldn't be run again.
-		return false
-	}
-
-	// Check dependencies.
-	for _, dep := range job.dependencies {
-		if dep.state != jobStateFinished {
-			// A dependency is not finished, so this job has to wait until it
-			// is.
-			return false
-		}
-	}
-
-	// All conditions are satisfied.
-	return true
-}
-
-// runJobs runs all the jobs indicated in the jobs slice and returns the error
-// of the first job that fails to run.
-// It runs all jobs in the order of the slice, as long as all dependencies have
-// already run. Therefore, if some jobs are preferred to run before others, they
-// should be ordered as such in this slice.
-func runJobs(jobs []*compileJob) error {
-	// Create channels to communicate with the workers.
-	doneChan := make(chan *compileJob)
-	workerChan := make(chan *compileJob)
-	defer close(workerChan)
-
-	// Start a number of workers.
-	for i := 0; i < runtime.NumCPU(); i++ {
-		if jobRunnerDebug {
-			fmt.Println("## starting worker", i)
-		}
-		go jobWorker(workerChan, doneChan)
-	}
-
-	// Send each job in the jobs slice to a worker, taking care of job
-	// dependencies.
-	numRunningJobs := 0
-	var totalTime time.Duration
-	start := time.Now()
-	for {
-		// If there are free workers, try starting a new job (if one is
-		// available). If it succeeds, try again to fill the entire worker pool.
-		if numRunningJobs < runtime.NumCPU() {
-			jobToRun := nextJob(jobs)
-			if jobToRun != nil {
-				// Start job.
-				if jobRunnerDebug {
-					fmt.Println("## start:   ", jobToRun.description)
-				}
-				jobToRun.state = jobStateRunning
-				workerChan <- jobToRun
-				numRunningJobs++
-				continue
-			}
-		}
-
-		// When there are no jobs running, all jobs in the jobs slice must have
-		// been finished. Therefore, the work is done.
-		if numRunningJobs == 0 {
-			break
-		}
-
-		// Wait until a job is finished.
-		job := <-doneChan
-		job.state = jobStateFinished
-		numRunningJobs--
-		totalTime += job.duration
-		if jobRunnerDebug {
-			fmt.Println("## finished:", job.description, "(time "+job.duration.String()+")")
-		}
-		if job.err != nil {
-			// Wait for running jobs to finish.
-			for numRunningJobs != 0 {
-				<-doneChan
-				numRunningJobs--
-			}
-			// Return error of first failing job.
-			return job.err
-		}
-	}
-
-	// Some statistics, if debugging.
-	if jobRunnerDebug {
-		// Total duration of running all jobs.
-		duration := time.Since(start)
-		fmt.Println("## total:   ", duration)
-
-		// The individual time of each job combined. On a multicore system, this
-		// should be lower than the total above.
-		fmt.Println("## job sum: ", totalTime)
-	}
-
-	return nil
-}
-
-// nextJob returns the first ready-to-run job.
-// This is an implementation detail of runJobs.
-func nextJob(jobs []*compileJob) *compileJob {
-	for _, job := range jobs {
-		if job.readyToRun() {
-			return job
-		}
-	}
-	return nil
-}
-
-// jobWorker is the goroutine that runs received jobs.
-// This is an implementation detail of runJobs.
-func jobWorker(workerChan, doneChan chan *compileJob) {
-	for job := range workerChan {
-		start := time.Now()
-		err := job.run()
-		if err != nil {
-			job.err = err
-		}
-		job.duration = time.Since(start)
-		doneChan <- job
-	}
-}

builder/library.go

@@ -1,6 +1,7 @@
 package builder
 
 import (
+	"io/ioutil"
 	"os"
 	"path/filepath"
 	"strings"
@@ -39,64 +40,34 @@ func (l *Library) sourcePaths(target string) []string {
 }
 
 // Load the library archive, possibly generating and caching it if needed.
-// The resulting file is stored in the provided tmpdir, which is expected to be
-// removed after the Load call.
-func (l *Library) Load(target, tmpdir string) (path string, err error) {
-	path, job, err := l.load(target, "", tmpdir)
-	if err != nil {
-		return "", err
-	}
-	if job != nil {
-		jobs := append([]*compileJob{job}, job.dependencies...)
-		err = runJobs(jobs)
-	}
-	return path, err
-}
-
-// load returns a path to the library file for the given target, loading it from
-// cache if possible. It will return a non-zero compiler job if the library
-// wasn't cached, this job (and its dependencies) must be run before the library
-// path is valid.
-// The provided tmpdir will be used to store intermediary files and possibly the
-// output archive file, it is expected to be removed after use.
-func (l *Library) load(target, cpu, tmpdir string) (path string, job *compileJob, err error) {
+func (l *Library) Load(target string) (path string, err error) {
 	// Try to load a precompiled library.
 	precompiledPath := filepath.Join(goenv.Get("TINYGOROOT"), "pkg", target, l.name+".a")
 	if _, err := os.Stat(precompiledPath); err == nil {
 		// Found a precompiled library for this OS/architecture. Return the path
 		// directly.
-		return precompiledPath, nil, nil
+		return precompiledPath, nil
 	}
 
-	var outfile string
-	if cpu != "" {
-		outfile = l.name + "-" + target + "-" + cpu + ".a"
-	} else {
-		outfile = l.name + "-" + target + ".a"
-	}
+	outfile := l.name + "-" + target + ".a"
 
 	// Try to fetch this library from the cache.
-	if path, err := cacheLoad(outfile, l.sourcePaths(target)); path != "" || err != nil {
+	if path, err := cacheLoad(outfile, commands["clang"][0], l.sourcePaths(target)); path != "" || err != nil {
 		// Cache hit.
-		return path, nil, err
+		return path, err
 	}
 	// Cache miss, build it now.
 
-	remapDir := filepath.Join(os.TempDir(), "tinygo-"+l.name)
-	dir := filepath.Join(tmpdir, "build-lib-"+l.name)
-	err = os.Mkdir(dir, 0777)
+	dirPrefix := "tinygo-" + l.name
+	remapDir := filepath.Join(os.TempDir(), dirPrefix)
+	dir, err := ioutil.TempDir(os.TempDir(), dirPrefix)
 	if err != nil {
-		return "", nil, err
+		return "", err
 	}
+	defer os.RemoveAll(dir)
 
 	// Precalculate the flags to the compiler invocation.
-	// Note: -fdebug-prefix-map is necessary to make the output archive
-	// reproducible. Otherwise the temporary directory is stored in the archive
-	// itself, which varies each run.
 	args := append(l.cflags(), "-c", "-Oz", "-g", "-ffunction-sections", "-fdata-sections", "-Wno-macro-redefined", "--target="+target, "-fdebug-prefix-map="+dir+"="+remapDir)
-	if cpu != "" {
-		args = append(args, "-mcpu="+cpu)
-	}
 	if strings.HasPrefix(target, "arm") || strings.HasPrefix(target, "thumb") {
 		args = append(args, "-fshort-enums", "-fomit-frame-pointer", "-mfloat-abi=soft")
 	}
@@ -107,44 +78,28 @@ func (l *Library) load(target, cpu, tmpdir string) (path string, job *compileJob
 		args = append(args, "-march=rv64gc", "-mabi=lp64")
 	}
 
-	// Create job to put all the object files in a single archive. This archive
-	// file is the (static) library file.
+	// Compile all sources.
 	var objs []string
-	arpath := filepath.Join(dir, l.name+".a")
-	job = &compileJob{
-		description: "ar " + l.name + ".a",
-		run: func() error {
-			// Create an archive of all object files.
-			err := makeArchive(arpath, objs)
-			if err != nil {
-				return err
-			}
-			// Store this archive in the cache.
-			_, err = cacheStore(arpath, outfile, l.sourcePaths(target))
-			return err
-		},
-	}
-
-	// Create jobs to compile all sources. These jobs are depended upon by the
-	// archive job above, so must be run first.
 	for _, srcpath := range l.sourcePaths(target) {
-		srcpath := srcpath // avoid concurrency issues by redefining inside the loop
 		objpath := filepath.Join(dir, filepath.Base(srcpath)+".o")
 		objs = append(objs, objpath)
-		job.dependencies = append(job.dependencies, &compileJob{
-			description: "compile " + srcpath,
-			run: func() error {
-				var compileArgs []string
-				compileArgs = append(compileArgs, args...)
-				compileArgs = append(compileArgs, "-o", objpath, srcpath)
-				err := runCCompiler("clang", compileArgs...)
-				if err != nil {
-					return &commandError{"failed to build", srcpath, err}
-				}
-				return nil
-			},
-		})
+		// Note: -fdebug-prefix-map is necessary to make the output archive
+		// reproducible. Otherwise the temporary directory is stored in the
+		// archive itself, which varies each run.
+		err := runCCompiler("clang", append(args, "-o", objpath, srcpath)...)
+		if err != nil {
+			return "", &commandError{"failed to build", srcpath, err}
+		}
 	}
 
-	return arpath, job, nil
+	// Put all the object files in a single archive. This archive file will be
+	// used to statically link this library.
+	arpath := filepath.Join(dir, l.name+".a")
+	err = makeArchive(arpath, objs)
+	if err != nil {
+		return "", err
+	}
+
+	// Store this archive in the cache.
+	return cacheStore(arpath, outfile, commands["clang"][0], l.sourcePaths(target))
 }

cgo/cgo.go

@@ -42,7 +42,6 @@ type cgoPackage struct {
 	enums           map[string]enumInfo
 	anonStructNum   int
 	ldflags         []string
-	visitedFiles    map[string][]byte
 }
 
 // constantInfo stores some information about a CGo constant found by libclang
@@ -55,10 +54,9 @@ type constantInfo struct {
 // functionInfo stores some information about a CGo function found by libclang
 // and declared in the AST.
 type functionInfo struct {
-	args     []paramInfo
-	results  *ast.FieldList
-	pos      token.Pos
-	variadic bool
+	args    []paramInfo
+	results *ast.FieldList
+	pos     token.Pos
 }
 
 // paramInfo is a parameter of a CGo function (see functionInfo).
@@ -157,10 +155,9 @@ typedef unsigned long long  _Cgo_ulonglong;
 // Process extracts `import "C"` statements from the AST, parses the comment
 // with libclang, and modifies the AST to use this information. It returns a
 // newly created *ast.File that should be added to the list of to-be-parsed
-// files, the LDFLAGS for this package, and a map of file hashes of the accessed
-// C header files. If there is one or more error, it returns these in the
-// []error slice but still modifies the AST.
-func Process(files []*ast.File, dir string, fset *token.FileSet, cflags []string) (*ast.File, []string, map[string][]byte, []error) {
+// files. If there is one or more error, it returns these in the []error slice
+// but still modifies the AST.
+func Process(files []*ast.File, dir string, fset *token.FileSet, cflags []string) (*ast.File, []string, []error) {
 	p := &cgoPackage{
 		dir:             dir,
 		fset:            fset,
@@ -172,7 +169,6 @@ func Process(files []*ast.File, dir string, fset *token.FileSet, cflags []string
 		typedefs:        map[string]*typedefInfo{},
 		elaboratedTypes: map[string]*elaboratedTypeInfo{},
 		enums:           map[string]enumInfo{},
-		visitedFiles:    map[string][]byte{},
 	}
 
 	// Disable _FORTIFY_SOURCE as it causes problems on macOS.
@@ -188,7 +184,7 @@ func Process(files []*ast.File, dir string, fset *token.FileSet, cflags []string
 	// Find the absolute path for this package.
 	packagePath, err := filepath.Abs(fset.File(files[0].Pos()).Name())
 	if err != nil {
-		return nil, nil, nil, []error{
+		return nil, nil, []error{
 			scanner.Error{
 				Pos: fset.Position(files[0].Pos()),
 				Msg: "cgo: cannot find absolute path: " + err.Error(), // TODO: wrap this error
@@ -430,7 +426,7 @@ func Process(files []*ast.File, dir string, fset *token.FileSet, cflags []string
 	// Print the newly generated in-memory AST, for debugging.
 	//ast.Print(fset, p.generated)
 
-	return p.generated, p.ldflags, p.visitedFiles, p.errors
+	return p.generated, p.ldflags, p.errors
 }
 
 // makePathsAbsolute converts some common path compiler flags (-I, -L) from
@@ -488,16 +484,6 @@ func (p *cgoPackage) addFuncDecls() {
 				Results: fn.results,
 			},
 		}
-		if fn.variadic {
-			decl.Doc = &ast.CommentGroup{
-				List: []*ast.Comment{
-					&ast.Comment{
-						Slash: fn.pos,
-						Text:  "//go:variadic",
-					},
-				},
-			}
-		}
 		obj.Decl = decl
 		for i, arg := range fn.args {
 			args[i] = &ast.Field{

cgo/cgo_test.go

@@ -5,7 +5,6 @@ import (
 	"flag"
 	"fmt"
 	"go/ast"
-	"go/build"
 	"go/format"
 	"go/parser"
 	"go/token"
@@ -24,7 +23,7 @@ var flagUpdate = flag.Bool("update", false, "Update images based on test output.
 // normalizeResult normalizes Go source code that comes out of tests across
 // platforms and Go versions.
 func normalizeResult(result string) string {
-	actual := strings.ReplaceAll(result, "\r\n", "\n")
+	actual := strings.Replace(result, "\r\n", "\n", -1)
 
 	// Make sure all functions are wrapped, even those that would otherwise be
 	// single-line functions. This is necessary because Go 1.14 changed the way
@@ -42,20 +41,6 @@ func TestCGo(t *testing.T) {
 	for _, name := range []string{"basic", "errors", "types", "flags", "const"} {
 		name := name // avoid a race condition
 		t.Run(name, func(t *testing.T) {
-			// Skip tests that require specific Go version.
-			if name == "errors" {
-				ok := false
-				for _, version := range build.Default.ReleaseTags {
-					if version == "go1.16" {
-						ok = true
-						break
-					}
-				}
-				if !ok {
-					t.Skip("Results for errors test are only valid for Go 1.16+")
-				}
-			}
-
 			// Read the AST in memory.
 			path := filepath.Join("testdata", name+".go")
 			fset := token.NewFileSet()
@@ -65,7 +50,7 @@ func TestCGo(t *testing.T) {
 			}
 
 			// Process the AST with CGo.
-			cgoAST, _, _, cgoErrors := Process([]*ast.File{f}, "testdata", fset, cflags)
+			cgoAST, _, cgoErrors := Process([]*ast.File{f}, "testdata", fset, cflags)
 
 			// Check the AST for type errors.
 			var typecheckErrors []error
@@ -113,7 +98,7 @@ func TestCGo(t *testing.T) {
 			if err != nil {
 				t.Fatalf("could not read expected output: %v", err)
 			}
-			expected := strings.ReplaceAll(string(expectedBytes), "\r\n", "\n")
+			expected := strings.Replace(string(expectedBytes), "\r\n", "\n", -1)
 
 			// Check whether the output is as expected.
 			if expected != actual {
@@ -154,7 +139,7 @@ func formatDiagnostic(err error) string {
 	msg := err.Error()
 	if runtime.GOOS == "windows" {
 		// Fix Windows path slashes.
-		msg = strings.ReplaceAll(msg, "testdata\\", "testdata/")
+		msg = strings.Replace(msg, "testdata\\", "testdata/", -1)
 	}
 	return "//     " + msg + "\n"
 }

cgo/libclang.go

@@ -4,7 +4,6 @@ package cgo
 // modification. It does not touch the AST itself.
 
 import (
-	"crypto/sha512"
 	"fmt"
 	"go/ast"
 	"go/scanner"
@@ -57,7 +56,6 @@ unsigned tinygo_clang_Cursor_isBitField(GoCXCursor c);
 int tinygo_clang_globals_visitor(GoCXCursor c, GoCXCursor parent, CXClientData client_data);
 int tinygo_clang_struct_visitor(GoCXCursor c, GoCXCursor parent, CXClientData client_data);
 int tinygo_clang_enum_visitor(GoCXCursor c, GoCXCursor parent, CXClientData client_data);
-void tinygo_clang_inclusion_visitor(CXFile included_file, CXSourceLocation *inclusion_stack, unsigned include_len, CXClientData client_data);
 */
 import "C"
 
@@ -116,7 +114,6 @@ func (p *cgoPackage) parseFragment(fragment string, cflags []string, posFilename
 	}
 	defer C.clang_disposeTranslationUnit(unit)
 
-	// Report parser and type errors.
 	if numDiagnostics := int(C.clang_getNumDiagnostics(unit)); numDiagnostics != 0 {
 		addDiagnostic := func(diagnostic C.CXDiagnostic) {
 			spelling := getString(C.clang_getDiagnosticSpelling(diagnostic))
@@ -137,36 +134,10 @@ func (p *cgoPackage) parseFragment(fragment string, cflags []string, posFilename
 		}
 	}
 
-	// Extract information required by CGo.
 	ref := storedRefs.Put(p)
 	defer storedRefs.Remove(ref)
 	cursor := C.tinygo_clang_getTranslationUnitCursor(unit)
 	C.tinygo_clang_visitChildren(cursor, C.CXCursorVisitor(C.tinygo_clang_globals_visitor), C.CXClientData(ref))
-
-	// Determine files read during CGo processing, for caching.
-	inclusionCallback := func(includedFile C.CXFile) {
-		// Get full file path.
-		path := getString(C.clang_getFileName(includedFile))
-
-		// Get contents of file (that should be in-memory).
-		size := C.size_t(0)
-		rawData := C.clang_getFileContents(unit, includedFile, &size)
-		if rawData == nil {
-			// Sanity check. This should (hopefully) never trigger.
-			panic("libclang: file contents was not loaded")
-		}
-		data := (*[1 << 24]byte)(unsafe.Pointer(rawData))[:size]
-
-		// Hash the contents if it isn't hashed yet.
-		if _, ok := p.visitedFiles[path]; !ok {
-			// already stored
-			sum := sha512.Sum512_224(data)
-			p.visitedFiles[path] = sum[:]
-		}
-	}
-	inclusionCallbackRef := storedRefs.Put(inclusionCallback)
-	defer storedRefs.Remove(inclusionCallbackRef)
-	C.clang_getInclusions(unit, C.CXInclusionVisitor(C.tinygo_clang_inclusion_visitor), C.CXClientData(inclusionCallbackRef))
 }
 
 //export tinygo_clang_globals_visitor
@@ -181,10 +152,12 @@ func tinygo_clang_globals_visitor(c, parent C.GoCXCursor, client_data C.CXClient
 			return C.CXChildVisit_Continue
 		}
 		cursorType := C.tinygo_clang_getCursorType(c)
+		if C.clang_isFunctionTypeVariadic(cursorType) != 0 {
+			return C.CXChildVisit_Continue // not supported
+		}
 		numArgs := int(C.tinygo_clang_Cursor_getNumArguments(c))
 		fn := &functionInfo{
-			pos:      pos,
-			variadic: C.clang_isFunctionTypeVariadic(cursorType) != 0,
+			pos: pos,
 		}
 		p.functions[name] = fn
 		for i := 0; i < numArgs; i++ {
@@ -801,9 +774,3 @@ func tinygo_clang_enum_visitor(c, parent C.GoCXCursor, client_data C.CXClientDat
 	}
 	return C.CXChildVisit_Continue
 }
-
-//export tinygo_clang_inclusion_visitor
-func tinygo_clang_inclusion_visitor(includedFile C.CXFile, inclusionStack *C.CXSourceLocation, includeLen C.unsigned, clientData C.CXClientData) {
-	callback := storedRefs.Get(unsafe.Pointer(clientData)).(func(C.CXFile))
-	callback(includedFile)
-}

cgo/libclang_config.go

@@ -1,14 +1,14 @@
 // +build !byollvm
-// +build !llvm10
+// +build !llvm9,!llvm11
 
 package cgo
 
 /*
-#cgo linux   CFLAGS:  -I/usr/lib/llvm-11/include
-#cgo darwin  CFLAGS:  -I/usr/local/opt/llvm@11/include
-#cgo freebsd CFLAGS:  -I/usr/local/llvm11/include
-#cgo linux   LDFLAGS: -L/usr/lib/llvm-11/lib -lclang
-#cgo darwin  LDFLAGS: -L/usr/local/opt/llvm@11/lib -lclang -lffi
-#cgo freebsd LDFLAGS: -L/usr/local/llvm11/lib -lclang
+#cgo linux  CFLAGS: -I/usr/lib/llvm-10/include
+#cgo darwin CFLAGS: -I/usr/local/opt/llvm@10/include
+#cgo freebsd CFLAGS: -I/usr/local/llvm10/include
+#cgo linux  LDFLAGS: -L/usr/lib/llvm-10/lib -lclang
+#cgo darwin LDFLAGS: -L/usr/local/opt/llvm@10/lib -lclang -lffi
+#cgo freebsd LDFLAGS: -L/usr/local/llvm10/lib -lclang
 */
 import "C"

cgo/libclang_config_llvm10.go

@@ -1,14 +0,0 @@
-// +build !byollvm
-// +build llvm10
-
-package cgo
-
-/*
-#cgo linux  CFLAGS: -I/usr/lib/llvm-10/include
-#cgo darwin CFLAGS: -I/usr/local/opt/llvm@10/include
-#cgo freebsd CFLAGS: -I/usr/local/llvm10/include
-#cgo linux  LDFLAGS: -L/usr/lib/llvm-10/lib -lclang
-#cgo darwin LDFLAGS: -L/usr/local/opt/llvm@10/lib -lclang -lffi
-#cgo freebsd LDFLAGS: -L/usr/local/llvm10/lib -lclang
-*/
-import "C"

cgo/libclang_config_llvm11.go

@@ -0,0 +1,14 @@
+// +build !byollvm
+// +build llvm11
+
+package cgo
+
+/*
+#cgo linux   CFLAGS:  -I/usr/lib/llvm-11/include
+#cgo darwin  CFLAGS:  -I/usr/local/opt/llvm@11/include
+#cgo freebsd CFLAGS:  -I/usr/local/llvm11/include
+#cgo linux   LDFLAGS: -L/usr/lib/llvm-11/lib -lclang
+#cgo darwin  LDFLAGS: -L/usr/local/opt/llvm@11/lib -lclang -lffi
+#cgo freebsd LDFLAGS: -L/usr/local/llvm11/lib -lclang
+*/
+import "C"

cgo/libclang_config_llvm9.go

@@ -0,0 +1,14 @@
+// +build !byollvm
+// +build llvm9
+
+package cgo
+
+/*
+#cgo linux  CFLAGS: -I/usr/lib/llvm-9/include
+#cgo darwin CFLAGS: -I/usr/local/opt/llvm@9/include
+#cgo freebsd CFLAGS: -I/usr/local/llvm9/include
+#cgo linux  LDFLAGS: -L/usr/lib/llvm-9/lib -lclang
+#cgo darwin LDFLAGS: -L/usr/local/opt/llvm@9/lib -lclang -lffi
+#cgo freebsd LDFLAGS: -L/usr/local/llvm9/lib -lclang
+*/
+import "C"

cgo/testdata/errors.out.go

@@ -4,10 +4,10 @@
 //     testdata/errors.go:13:23: unexpected token )
 
 // Type checking errors after CGo processing:
-//     testdata/errors.go:102: cannot use 2 << 10 (untyped int constant 2048) as uint8 value in variable declaration (overflows)
+//     testdata/errors.go:102: 2 << 10 (untyped int constant 2048) overflows uint8
 //     testdata/errors.go:105: unknown field z in struct literal
 //     testdata/errors.go:108: undeclared name: C.SOME_CONST_1
-//     testdata/errors.go:110: cannot use C.SOME_CONST_3 (untyped int constant 1234) as byte value in variable declaration (overflows)
+//     testdata/errors.go:110: C.SOME_CONST_3 (untyped int constant 1234) overflows byte
 
 package main
 

cgo/testdata/types.go

@@ -104,10 +104,6 @@ typedef struct {
 	unsigned char e : 3;
 	// Note that C++ allows bitfields bigger than the underlying type.
 } bitfield_t;
-
-// Function signatures.
-void variadic0();
-void variadic2(int x, int y, ...);
 */
 import "C"
 
@@ -167,9 +163,3 @@ func accessUnion() {
 	var _ *C.int = union2d.unionfield_i()
 	var _ *[2]float64 = union2d.unionfield_d()
 }
-
-// Test function signatures.
-func accessFunctions() {
-	C.variadic0()
-	C.variadic2(3, 5)
-}

cgo/testdata/types.out.go

@@ -4,11 +4,6 @@ import "unsafe"
 
 var _ unsafe.Pointer
 
-func C.variadic0() //go:variadic
-func C.variadic2(x C.int, y C.int) //go:variadic
-var C.variadic0$funcaddr unsafe.Pointer
-var C.variadic2$funcaddr unsafe.Pointer
-
 const C.option2A = 20
 const C.optionA = 0
 const C.optionB = 1

compileopts/config.go

@@ -21,6 +21,29 @@ type Config struct {
 	TestConfig     TestConfig
 }
 
+// FuncValueImplementation is an enum for the particular implementations of Go
+// func values.
+type FuncValueImplementation int
+
+// These constants describe the various possible implementations of Go func
+// values.
+const (
+	FuncValueNone FuncValueImplementation = iota
+
+	// A func value is implemented as a pair of pointers:
+	//     {context, function pointer}
+	// where the context may be a pointer to a heap-allocated struct containing
+	// the free variables, or it may be undef if the function being pointed to
+	// doesn't need a context. The function pointer is a regular function
+	// pointer.
+	FuncValueDoubleword
+
+	// As funcValueDoubleword, but with the function pointer replaced by a
+	// unique ID per function signature. Function values are called by using a
+	// switch statement and choosing which function to call.
+	FuncValueSwitch
+)
+
 // Triple returns the LLVM target triple, like armv6m-none-eabi.
 func (c *Config) Triple() string {
 	return c.Target.Triple
@@ -120,24 +143,14 @@ func (c *Config) Scheduler() string {
 
 // FuncImplementation picks an appropriate func value implementation for the
 // target.
-func (c *Config) FuncImplementation() string {
+func (c *Config) FuncImplementation() FuncValueImplementation {
+	// Always pick the switch implementation, as it allows the use of blocking
+	// inside a function that is used as a func value.
 	switch c.Scheduler() {
-	case "tasks":
-		// A func value is implemented as a pair of pointers:
-		//     {context, function pointer}
-		// where the context may be a pointer to a heap-allocated struct
-		// containing the free variables, or it may be undef if the function
-		// being pointed to doesn't need a context. The function pointer is a
-		// regular function pointer.
-		return "doubleword"
 	case "none", "coroutines":
-		// As "doubleword", but with the function pointer replaced by a unique
-		// ID per function signature. Function values are called by using a
-		// switch statement and choosing which function to call.
-		// Pick the switch implementation with the coroutines scheduler, as it
-		// allows the use of blocking inside a function that is used as a func
-		// value.
-		return "switch"
+		return FuncValueSwitch
+	case "tasks":
+		return FuncValueDoubleword
 	default:
 		panic("unknown scheduler type")
 	}
@@ -165,7 +178,7 @@ func (c *Config) AutomaticStackSize() bool {
 func (c *Config) CFlags() []string {
 	cflags := append([]string{}, c.Options.CFlags...)
 	for _, flag := range c.Target.CFlags {
-		cflags = append(cflags, strings.ReplaceAll(flag, "{root}", goenv.Get("TINYGOROOT")))
+		cflags = append(cflags, strings.Replace(flag, "{root}", goenv.Get("TINYGOROOT"), -1))
 	}
 	if c.Target.Libc == "picolibc" {
 		root := goenv.Get("TINYGOROOT")
@@ -186,7 +199,7 @@ func (c *Config) LDFlags() []string {
 	// Merge and adjust LDFlags.
 	ldflags := append([]string{}, c.Options.LDFlags...)
 	for _, flag := range c.Target.LDFlags {
-		ldflags = append(ldflags, strings.ReplaceAll(flag, "{root}", root))
+		ldflags = append(ldflags, strings.Replace(flag, "{root}", root, -1))
 	}
 	ldflags = append(ldflags, "-L", root)
 	if c.Target.LinkerScript != "" {

compiler/asserts.go

@@ -16,7 +16,7 @@ import (
 // slice. This is required by the Go language spec: an index out of bounds must
 // cause a panic.
 func (b *builder) createLookupBoundsCheck(arrayLen, index llvm.Value, indexType types.Type) {
-	if b.info.nobounds {
+	if b.fn.IsNoBounds() {
 		// The //go:nobounds pragma was added to the function to avoid bounds
 		// checking.
 		return
@@ -48,7 +48,7 @@ func (b *builder) createLookupBoundsCheck(arrayLen, index llvm.Value, indexType
 // biggest possible slice capacity, 'low' means len and 'high' means cap. The
 // logic is the same in both cases.
 func (b *builder) createSliceBoundsCheck(capacity, low, high, max llvm.Value, lowType, highType, maxType *types.Basic) {
-	if b.info.nobounds {
+	if b.fn.IsNoBounds() {
 		// The //go:nobounds pragma was added to the function to avoid bounds
 		// checking.
 		return
@@ -104,7 +104,7 @@ func (b *builder) createSliceBoundsCheck(capacity, low, high, max llvm.Value, lo
 // createChanBoundsCheck creates a bounds check before creating a new channel to
 // check that the value is not too big for runtime.chanMake.
 func (b *builder) createChanBoundsCheck(elementSize uint64, bufSize llvm.Value, bufSizeType *types.Basic, pos token.Pos) {
-	if b.info.nobounds {
+	if b.fn.IsNoBounds() {
 		// The //go:nobounds pragma was added to the function to avoid bounds
 		// checking.
 		return
@@ -189,7 +189,7 @@ func (b *builder) createNilCheck(inst ssa.Value, ptr llvm.Value, blockPrefix str
 // createNegativeShiftCheck creates an assertion that panics if the given shift value is negative.
 // This function assumes that the shift value is signed.
 func (b *builder) createNegativeShiftCheck(shift llvm.Value) {
-	if b.info.nobounds {
+	if b.fn.IsNoBounds() {
 		// Function disabled bounds checking - skip shift check.
 		return
 	}
@@ -212,8 +212,8 @@ func (b *builder) createRuntimeAssert(assert llvm.Value, blockPrefix, assertFunc
 		}
 	}
 
-	faultBlock := b.ctx.AddBasicBlock(b.llvmFn, blockPrefix+".throw")
-	nextBlock := b.ctx.AddBasicBlock(b.llvmFn, blockPrefix+".next")
+	faultBlock := b.ctx.AddBasicBlock(b.fn.LLVMFn, blockPrefix+".throw")
+	nextBlock := b.ctx.AddBasicBlock(b.fn.LLVMFn, blockPrefix+".next")
 	b.blockExits[b.currentBlock] = nextBlock // adjust outgoing block for phi nodes
 
 	// Now branch to the out-of-bounds or the regular block.

compiler/atomic.go

@@ -1,8 +1,6 @@
 package compiler
 
 import (
-	"strings"
-
 	"golang.org/x/tools/go/ssa"
 	"tinygo.org/x/go-llvm"
 )
@@ -37,31 +35,6 @@ func (b *builder) createAtomicOp(call *ssa.CallCommon) (llvm.Value, bool) {
 		ptr := b.getValue(call.Args[0])
 		old := b.getValue(call.Args[1])
 		newVal := b.getValue(call.Args[2])
-		if strings.HasSuffix(name, "64") {
-			arch := strings.Split(b.Triple, "-")[0]
-			if strings.HasPrefix(arch, "arm") && strings.HasSuffix(arch, "m") {
-				// Work around a bug in LLVM, at least LLVM 11:
-				// https://reviews.llvm.org/D95891
-				// Check for armv6m, armv7, armv7em, and perhaps others.
-				// See also: https://gcc.gnu.org/onlinedocs/gcc/_005f_005fsync-Builtins.html
-				compareAndSwap := b.mod.NamedFunction("__sync_val_compare_and_swap_8")
-				if compareAndSwap.IsNil() {
-					// Declare the function if it isn't already declared.
-					i64Type := b.ctx.Int64Type()
-					fnType := llvm.FunctionType(i64Type, []llvm.Type{llvm.PointerType(i64Type, 0), i64Type, i64Type}, false)
-					compareAndSwap = llvm.AddFunction(b.mod, "__sync_val_compare_and_swap_8", fnType)
-				}
-				actualOldValue := b.CreateCall(compareAndSwap, []llvm.Value{ptr, old, newVal}, "")
-				// The __sync_val_compare_and_swap_8 function returns the old
-				// value. However, we shouldn't return the old value, we should
-				// return whether the compare/exchange was successful. This is
-				// easily done by comparing the returned (actual) old value with
-				// the expected old value passed to
-				// __sync_val_compare_and_swap_8.
-				swapped := b.CreateICmp(llvm.IntEQ, old, actualOldValue, "")
-				return swapped, true
-			}
-		}
 		tuple := b.CreateAtomicCmpXchg(ptr, old, newVal, llvm.AtomicOrderingSequentiallyConsistent, llvm.AtomicOrderingSequentiallyConsistent, true)
 		swapped := b.CreateExtractValue(tuple, 1, "")
 		return swapped, true

compiler/calls.go

@@ -4,7 +4,6 @@ import (
 	"go/types"
 	"strconv"
 
-	"golang.org/x/tools/go/ssa"
 	"tinygo.org/x/go-llvm"
 )
 
@@ -35,14 +34,14 @@ const (
 
 // createCall creates a new call to runtime.<fnName> with the given arguments.
 func (b *builder) createRuntimeCall(fnName string, args []llvm.Value, name string) llvm.Value {
-	fn := b.program.ImportedPackage("runtime").Members[fnName].(*ssa.Function)
-	llvmFn := b.getFunction(fn)
-	if llvmFn.IsNil() {
-		panic("trying to call non-existent function: " + fn.RelString(nil))
+	fullName := "runtime." + fnName
+	fn := b.mod.NamedFunction(fullName)
+	if fn.IsNil() {
+		panic("trying to call non-existent function: " + fullName)
 	}
 	args = append(args, llvm.Undef(b.i8ptrType))            // unused context parameter
 	args = append(args, llvm.ConstPointerNull(b.i8ptrType)) // coroutine handle
-	return b.createCall(llvmFn, args, name)
+	return b.createCall(fn, args, name)
 }
 
 // createCall creates a call to the given function with the arguments possibly

compiler/channel.go

@@ -79,7 +79,8 @@ func (b *builder) createChanRecv(unop *ssa.UnOp) llvm.Value {
 }
 
 // createChanClose closes the given channel.
-func (b *builder) createChanClose(ch llvm.Value) {
+func (b *builder) createChanClose(param ssa.Value) {
+	ch := b.getValue(param)
 	b.createRuntimeCall("chanClose", []llvm.Value{ch}, "")
 }
 

compiler/compiler_test.go

@@ -28,17 +28,7 @@ func TestCompiler(t *testing.T) {
 		Options: &compileopts.Options{},
 		Target:  target,
 	}
-	compilerConfig := &Config{
-		Triple:             config.Triple(),
-		GOOS:               config.GOOS(),
-		GOARCH:             config.GOARCH(),
-		CodeModel:          config.CodeModel(),
-		RelocationModel:    config.RelocationModel(),
-		Scheduler:          config.Scheduler(),
-		FuncImplementation: config.FuncImplementation(),
-		AutomaticStackSize: config.AutomaticStackSize(),
-	}
-	machine, err := NewTargetMachine(compilerConfig)
+	machine, err := NewTargetMachine(config)
 	if err != nil {
 		t.Fatal("failed to create target machine:", err)
 	}
@@ -47,7 +37,6 @@ func TestCompiler(t *testing.T) {
 		"basic.go",
 		"pointer.go",
 		"slice.go",
-		"float.go",
 	}
 
 	for _, testCase := range tests {
@@ -65,9 +54,8 @@ func TestCompiler(t *testing.T) {
 			}
 
 			// Compile AST to IR.
-			program := lprogram.LoadSSA()
 			pkg := lprogram.MainPkg()
-			mod, errs := CompilePackage(testCase, pkg, program.Package(pkg.Pkg), machine, compilerConfig, false)
+			mod, errs := CompilePackage(testCase, pkg, machine, config)
 			if errs != nil {
 				for _, err := range errs {
 					t.Log("error:", err)

compiler/defer.go

@@ -14,9 +14,9 @@ package compiler
 //     frames.
 
 import (
-	"go/types"
-
 	"github.com/tinygo-org/tinygo/compiler/llvmutil"
+	"github.com/tinygo-org/tinygo/ir"
+	"go/types"
 	"golang.org/x/tools/go/ssa"
 	"tinygo.org/x/go-llvm"
 )
@@ -26,9 +26,9 @@ import (
 // calls.
 func (b *builder) deferInitFunc() {
 	// Some setup.
-	b.deferFuncs = make(map[*ssa.Function]int)
+	b.deferFuncs = make(map[*ir.Function]int)
 	b.deferInvokeFuncs = make(map[string]int)
-	b.deferClosureFuncs = make(map[*ssa.Function]int)
+	b.deferClosureFuncs = make(map[*ir.Function]int)
 	b.deferExprFuncs = make(map[ssa.Value]int)
 	b.deferBuiltinFuncs = make(map[ssa.Value]deferBuiltin)
 
@@ -107,11 +107,13 @@ func (b *builder) createDefer(instr *ssa.Defer) {
 
 	} else if callee, ok := instr.Call.Value.(*ssa.Function); ok {
 		// Regular function call.
-		if _, ok := b.deferFuncs[callee]; !ok {
-			b.deferFuncs[callee] = len(b.allDeferFuncs)
-			b.allDeferFuncs = append(b.allDeferFuncs, callee)
+		fn := b.ir.GetFunction(callee)
+
+		if _, ok := b.deferFuncs[fn]; !ok {
+			b.deferFuncs[fn] = len(b.allDeferFuncs)
+			b.allDeferFuncs = append(b.allDeferFuncs, fn)
 		}
-		callback := llvm.ConstInt(b.uintptrType, uint64(b.deferFuncs[callee]), false)
+		callback := llvm.ConstInt(b.uintptrType, uint64(b.deferFuncs[fn]), false)
 
 		// Collect all values to be put in the struct (starting with
 		// runtime._defer fields).
@@ -133,7 +135,7 @@ func (b *builder) createDefer(instr *ssa.Defer) {
 		context := b.CreateExtractValue(closure, 0, "")
 
 		// Get the callback number.
-		fn := makeClosure.Fn.(*ssa.Function)
+		fn := b.ir.GetFunction(makeClosure.Fn.(*ssa.Function))
 		if _, ok := b.deferClosureFuncs[fn]; !ok {
 			b.deferClosureFuncs[fn] = len(b.allDeferFuncs)
 			b.allDeferFuncs = append(b.allDeferFuncs, makeClosure)
@@ -153,19 +155,19 @@ func (b *builder) createDefer(instr *ssa.Defer) {
 		valueTypes = append(valueTypes, context.Type())
 
 	} else if builtin, ok := instr.Call.Value.(*ssa.Builtin); ok {
-		var argTypes []types.Type
-		var argValues []llvm.Value
-		for _, arg := range instr.Call.Args {
-			argTypes = append(argTypes, arg.Type())
-			argValues = append(argValues, b.getValue(arg))
+		var funcName string
+		switch builtin.Name() {
+		case "close":
+			funcName = "chanClose"
+		default:
+			b.addError(instr.Pos(), "todo: Implement defer for "+builtin.Name())
+			return
 		}
 
 		if _, ok := b.deferBuiltinFuncs[instr.Call.Value]; !ok {
 			b.deferBuiltinFuncs[instr.Call.Value] = deferBuiltin{
-				callName: builtin.Name(),
-				pos:      builtin.Pos(),
-				argTypes: argTypes,
-				callback: len(b.allDeferFuncs),
+				funcName,
+				len(b.allDeferFuncs),
 			}
 			b.allDeferFuncs = append(b.allDeferFuncs, instr.Call.Value)
 		}
@@ -174,9 +176,10 @@ func (b *builder) createDefer(instr *ssa.Defer) {
 		// Collect all values to be put in the struct (starting with
 		// runtime._defer fields).
 		values = []llvm.Value{callback, next}
-		for _, param := range argValues {
-			values = append(values, param)
-			valueTypes = append(valueTypes, param.Type())
+		for _, param := range instr.Call.Args {
+			llvmParam := b.getValue(param)
+			values = append(values, llvmParam)
+			valueTypes = append(valueTypes, llvmParam.Type())
 		}
 
 	} else {
@@ -220,7 +223,7 @@ func (b *builder) createDefer(instr *ssa.Defer) {
 		allocCall := b.createRuntimeCall("alloc", []llvm.Value{sizeValue}, "defer.alloc.call")
 		alloca = b.CreateBitCast(allocCall, llvm.PointerType(deferFrameType, 0), "defer.alloc")
 	}
-	if b.NeedsStackObjects {
+	if b.NeedsStackObjects() {
 		b.trackPointer(alloca)
 	}
 	b.CreateStore(deferFrame, alloca)
@@ -248,10 +251,10 @@ func (b *builder) createRunDefers() {
 	//     }
 
 	// Create loop.
-	loophead := b.ctx.AddBasicBlock(b.llvmFn, "rundefers.loophead")
-	loop := b.ctx.AddBasicBlock(b.llvmFn, "rundefers.loop")
-	unreachable := b.ctx.AddBasicBlock(b.llvmFn, "rundefers.default")
-	end := b.ctx.AddBasicBlock(b.llvmFn, "rundefers.end")
+	loophead := b.ctx.AddBasicBlock(b.fn.LLVMFn, "rundefers.loophead")
+	loop := b.ctx.AddBasicBlock(b.fn.LLVMFn, "rundefers.loop")
+	unreachable := b.ctx.AddBasicBlock(b.fn.LLVMFn, "rundefers.default")
+	end := b.ctx.AddBasicBlock(b.fn.LLVMFn, "rundefers.end")
 	b.CreateBr(loophead)
 
 	// Create loop head:
@@ -283,7 +286,7 @@ func (b *builder) createRunDefers() {
 		// Create switch case, for example:
 		//     case 0:
 		//         // run first deferred call
-		block := b.ctx.AddBasicBlock(b.llvmFn, "rundefers.callback")
+		block := b.ctx.AddBasicBlock(b.fn.LLVMFn, "rundefers.callback")
 		sw.AddCase(llvm.ConstInt(b.uintptrType, uint64(i), false), block)
 		b.SetInsertPointAtEnd(block)
 		switch callback := callback.(type) {
@@ -347,12 +350,12 @@ func (b *builder) createRunDefers() {
 
 			b.createCall(fnPtr, forwardParams, "")
 
-		case *ssa.Function:
+		case *ir.Function:
 			// Direct call.
 
 			// Get the real defer struct type and cast to it.
 			valueTypes := []llvm.Type{b.uintptrType, llvm.PointerType(b.getLLVMRuntimeType("_defer"), 0)}
-			for _, param := range getParams(callback.Signature) {
+			for _, param := range callback.Params {
 				valueTypes = append(valueTypes, b.getLLVMType(param.Type()))
 			}
 			deferFrameType := b.ctx.StructType(valueTypes, false)
@@ -361,7 +364,7 @@ func (b *builder) createRunDefers() {
 			// Extract the params from the struct.
 			forwardParams := []llvm.Value{}
 			zero := llvm.ConstInt(b.ctx.Int32Type(), 0, false)
-			for i := range getParams(callback.Signature) {
+			for i := range callback.Params {
 				gep := b.CreateInBoundsGEP(deferFramePtr, []llvm.Value{zero, llvm.ConstInt(b.ctx.Int32Type(), uint64(i+2), false)}, "gep")
 				forwardParam := b.CreateLoad(gep, "param")
 				forwardParams = append(forwardParams, forwardParam)
@@ -369,7 +372,7 @@ func (b *builder) createRunDefers() {
 
 			// Plain TinyGo functions add some extra parameters to implement async functionality and function recievers.
 			// These parameters should not be supplied when calling into an external C/ASM function.
-			if !b.getFunctionInfo(callback).exported {
+			if !callback.IsExported() {
 				// Add the context parameter. We know it is ignored by the receiving
 				// function, but we have to pass one anyway.
 				forwardParams = append(forwardParams, llvm.Undef(b.i8ptrType))
@@ -379,11 +382,11 @@ func (b *builder) createRunDefers() {
 			}
 
 			// Call real function.
-			b.createCall(b.getFunction(callback), forwardParams, "")
+			b.createCall(callback.LLVMFn, forwardParams, "")
 
 		case *ssa.MakeClosure:
 			// Get the real defer struct type and cast to it.
-			fn := callback.Fn.(*ssa.Function)
+			fn := b.ir.GetFunction(callback.Fn.(*ssa.Function))
 			valueTypes := []llvm.Type{b.uintptrType, llvm.PointerType(b.getLLVMRuntimeType("_defer"), 0)}
 			params := fn.Signature.Params()
 			for i := 0; i < params.Len(); i++ {
@@ -406,7 +409,7 @@ func (b *builder) createRunDefers() {
 			forwardParams = append(forwardParams, llvm.Undef(b.i8ptrType))
 
 			// Call deferred function.
-			b.createCall(b.getFunction(fn), forwardParams, "")
+			b.createCall(fn.LLVMFn, forwardParams, "")
 		case *ssa.Builtin:
 			db := b.deferBuiltinFuncs[callback]
 
@@ -423,18 +426,15 @@ func (b *builder) createRunDefers() {
 			deferFramePtr := b.CreateBitCast(deferData, llvm.PointerType(deferFrameType, 0), "deferFrame")
 
 			// Extract the params from the struct.
-			var argValues []llvm.Value
+			var forwardParams []llvm.Value
 			zero := llvm.ConstInt(b.ctx.Int32Type(), 0, false)
 			for i := 0; i < params.Len(); i++ {
 				gep := b.CreateInBoundsGEP(deferFramePtr, []llvm.Value{zero, llvm.ConstInt(b.ctx.Int32Type(), uint64(i+2), false)}, "gep")
 				forwardParam := b.CreateLoad(gep, "param")
-				argValues = append(argValues, forwardParam)
+				forwardParams = append(forwardParams, forwardParam)
 			}
 
-			_, err := b.createBuiltin(db.argTypes, argValues, db.callName, db.pos)
-			if err != nil {
-				b.diagnostics = append(b.diagnostics, err)
-			}
+			b.createRuntimeCall(db.funcName, forwardParams, "")
 		default:
 			panic("unknown deferred function type")
 		}

compiler/errors.go

@@ -14,7 +14,7 @@ import (
 // makeError makes it easy to create an error from a token.Pos with a message.
 func (c *compilerContext) makeError(pos token.Pos, msg string) types.Error {
 	return types.Error{
-		Fset: c.program.Fset,
+		Fset: c.ir.Program.Fset,
 		Pos:  pos,
 		Msg:  msg,
 	}

compiler/func.go

@@ -6,6 +6,7 @@ package compiler
 import (
 	"go/types"
 
+	"github.com/tinygo-org/tinygo/compileopts"
 	"golang.org/x/tools/go/ssa"
 	"tinygo.org/x/go-llvm"
 )
@@ -20,11 +21,11 @@ func (b *builder) createFuncValue(funcPtr, context llvm.Value, sig *types.Signat
 // context.
 func (c *compilerContext) createFuncValue(builder llvm.Builder, funcPtr, context llvm.Value, sig *types.Signature) llvm.Value {
 	var funcValueScalar llvm.Value
-	switch c.FuncImplementation {
-	case "doubleword":
+	switch c.FuncImplementation() {
+	case compileopts.FuncValueDoubleword:
 		// Closure is: {context, function pointer}
 		funcValueScalar = funcPtr
-	case "switch":
+	case compileopts.FuncValueSwitch:
 		sigGlobal := c.getTypeCode(sig)
 		funcValueWithSignatureGlobalName := funcPtr.Name() + "$withSignature"
 		funcValueWithSignatureGlobal := c.mod.NamedGlobal(funcValueWithSignatureGlobalName)
@@ -37,7 +38,7 @@ func (c *compilerContext) createFuncValue(builder llvm.Builder, funcPtr, context
 			funcValueWithSignatureGlobal = llvm.AddGlobal(c.mod, funcValueWithSignatureType, funcValueWithSignatureGlobalName)
 			funcValueWithSignatureGlobal.SetInitializer(funcValueWithSignature)
 			funcValueWithSignatureGlobal.SetGlobalConstant(true)
-			funcValueWithSignatureGlobal.SetLinkage(llvm.LinkOnceODRLinkage)
+			funcValueWithSignatureGlobal.SetLinkage(llvm.InternalLinkage)
 		}
 		funcValueScalar = llvm.ConstPtrToInt(funcValueWithSignatureGlobal, c.uintptrType)
 	default:
@@ -66,10 +67,10 @@ func (b *builder) extractFuncContext(funcValue llvm.Value) llvm.Value {
 // value. This may be an expensive operation.
 func (b *builder) decodeFuncValue(funcValue llvm.Value, sig *types.Signature) (funcPtr, context llvm.Value) {
 	context = b.CreateExtractValue(funcValue, 0, "")
-	switch b.FuncImplementation {
-	case "doubleword":
+	switch b.FuncImplementation() {
+	case compileopts.FuncValueDoubleword:
 		funcPtr = b.CreateExtractValue(funcValue, 1, "")
-	case "switch":
+	case compileopts.FuncValueSwitch:
 		llvmSig := b.getRawFuncType(sig)
 		sigGlobal := b.getTypeCode(sig)
 		funcPtr = b.createRuntimeCall("getFuncPtr", []llvm.Value{funcValue, sigGlobal}, "")
@@ -82,11 +83,11 @@ func (b *builder) decodeFuncValue(funcValue llvm.Value, sig *types.Signature) (f
 
 // getFuncType returns the type of a func value given a signature.
 func (c *compilerContext) getFuncType(typ *types.Signature) llvm.Type {
-	switch c.FuncImplementation {
-	case "doubleword":
+	switch c.FuncImplementation() {
+	case compileopts.FuncValueDoubleword:
 		rawPtr := c.getRawFuncType(typ)
 		return c.ctx.StructType([]llvm.Type{c.i8ptrType, rawPtr}, false)
-	case "switch":
+	case compileopts.FuncValueSwitch:
 		return c.getLLVMRuntimeType("funcValue")
 	default:
 		panic("unimplemented func value variant")
@@ -148,7 +149,7 @@ func (b *builder) parseMakeClosure(expr *ssa.MakeClosure) (llvm.Value, error) {
 	if len(expr.Bindings) == 0 {
 		panic("unexpected: MakeClosure without bound variables")
 	}
-	f := expr.Fn.(*ssa.Function)
+	f := b.ir.GetFunction(expr.Fn.(*ssa.Function))
 
 	// Collect all bound variables.
 	boundVars := make([]llvm.Value, len(expr.Bindings))
@@ -163,5 +164,5 @@ func (b *builder) parseMakeClosure(expr *ssa.MakeClosure) (llvm.Value, error) {
 	context := b.emitPointerPack(boundVars)
 
 	// Create the closure.
-	return b.createFuncValue(b.getFunction(f), context, f.Signature), nil
+	return b.createFuncValue(f.LLVMFn, context, f.Signature), nil
 }

compiler/goroutine.go

@@ -7,7 +7,6 @@ import (
 	"go/token"
 
 	"github.com/tinygo-org/tinygo/compiler/llvmutil"
-	"golang.org/x/tools/go/ssa"
 	"tinygo.org/x/go-llvm"
 )
 
@@ -21,20 +20,19 @@ import (
 func (b *builder) createGoInstruction(funcPtr llvm.Value, params []llvm.Value, prefix string, pos token.Pos) llvm.Value {
 	paramBundle := b.emitPointerPack(params)
 	var callee, stackSize llvm.Value
-	switch b.Scheduler {
+	switch b.Scheduler() {
 	case "none", "tasks":
 		callee = b.createGoroutineStartWrapper(funcPtr, prefix, pos)
-		if b.AutomaticStackSize {
+		if b.AutomaticStackSize() {
 			// The stack size is not known until after linking. Call a dummy
 			// function that will be replaced with a load from a special ELF
 			// section that contains the stack size (and is modified after
 			// linking).
-			stackSizeFn := b.getFunction(b.program.ImportedPackage("internal/task").Members["getGoroutineStackSize"].(*ssa.Function))
-			stackSize = b.createCall(stackSizeFn, []llvm.Value{callee, llvm.Undef(b.i8ptrType), llvm.Undef(b.i8ptrType)}, "stacksize")
+			stackSize = b.createCall(b.mod.NamedFunction("internal/task.getGoroutineStackSize"), []llvm.Value{callee, llvm.Undef(b.i8ptrType), llvm.Undef(b.i8ptrType)}, "stacksize")
 		} else {
 			// The stack size is fixed at compile time. By emitting it here as a
 			// constant, it can be optimized.
-			stackSize = llvm.ConstInt(b.uintptrType, b.DefaultStackSize, false)
+			stackSize = llvm.ConstInt(b.uintptrType, b.Target.DefaultStackSize, false)
 		}
 	case "coroutines":
 		callee = b.CreatePtrToInt(funcPtr, b.uintptrType, "")
@@ -44,8 +42,7 @@ func (b *builder) createGoInstruction(funcPtr llvm.Value, params []llvm.Value, p
 	default:
 		panic("unreachable")
 	}
-	start := b.getFunction(b.program.ImportedPackage("internal/task").Members["start"].(*ssa.Function))
-	b.createCall(start, []llvm.Value{callee, paramBundle, stackSize, llvm.Undef(b.i8ptrType), llvm.ConstPointerNull(b.i8ptrType)}, "")
+	b.createCall(b.mod.NamedFunction("internal/task.start"), []llvm.Value{callee, paramBundle, stackSize, llvm.Undef(b.i8ptrType), llvm.ConstPointerNull(b.i8ptrType)}, "")
 	return llvm.Undef(funcPtr.Type().ElementType().ReturnType())
 }
 
@@ -84,14 +81,14 @@ func (c *compilerContext) createGoroutineStartWrapper(fn llvm.Value, prefix stri
 		// Create the wrapper.
 		wrapperType := llvm.FunctionType(c.ctx.VoidType(), []llvm.Type{c.i8ptrType}, false)
 		wrapper = llvm.AddFunction(c.mod, name+"$gowrapper", wrapperType)
-		wrapper.SetLinkage(llvm.LinkOnceODRLinkage)
+		wrapper.SetLinkage(llvm.InternalLinkage)
 		wrapper.SetUnnamedAddr(true)
 		wrapper.AddAttributeAtIndex(-1, c.ctx.CreateStringAttribute("tinygo-gowrapper", name))
 		entry := c.ctx.AddBasicBlock(wrapper, "entry")
 		builder.SetInsertPointAtEnd(entry)
 
-		if c.Debug {
-			pos := c.program.Fset.Position(pos)
+		if c.Debug() {
+			pos := c.ir.Program.Fset.Position(pos)
 			diFuncType := c.dibuilder.CreateSubroutineType(llvm.DISubroutineType{
 				File:       c.getDIFile(pos.Filename),
 				Parameters: nil, // do not show parameters in debugger
@@ -141,14 +138,14 @@ func (c *compilerContext) createGoroutineStartWrapper(fn llvm.Value, prefix stri
 		// Create the wrapper.
 		wrapperType := llvm.FunctionType(c.ctx.VoidType(), []llvm.Type{c.i8ptrType}, false)
 		wrapper = llvm.AddFunction(c.mod, prefix+".gowrapper", wrapperType)
-		wrapper.SetLinkage(llvm.LinkOnceODRLinkage)
+		wrapper.SetLinkage(llvm.InternalLinkage)
 		wrapper.SetUnnamedAddr(true)
 		wrapper.AddAttributeAtIndex(-1, c.ctx.CreateStringAttribute("tinygo-gowrapper", ""))
 		entry := c.ctx.AddBasicBlock(wrapper, "entry")
 		builder.SetInsertPointAtEnd(entry)
 
-		if c.Debug {
-			pos := c.program.Fset.Position(pos)
+		if c.Debug() {
+			pos := c.ir.Program.Fset.Position(pos)
 			diFuncType := c.dibuilder.CreateSubroutineType(llvm.DISubroutineType{
 				File:       c.getDIFile(pos.Filename),
 				Parameters: nil, // do not show parameters in debugger

compiler/interface.go

@@ -11,6 +11,7 @@ import (
 	"strconv"
 	"strings"
 
+	"github.com/tinygo-org/tinygo/ir"
 	"golang.org/x/tools/go/ssa"
 	"tinygo.org/x/go-llvm"
 )
@@ -31,7 +32,7 @@ func (b *builder) createMakeInterface(val llvm.Value, typ types.Type, pos token.
 		itfConcreteTypeGlobal = llvm.AddGlobal(b.mod, typeInInterface, "typeInInterface:"+itfTypeCodeGlobal.Name())
 		itfConcreteTypeGlobal.SetInitializer(llvm.ConstNamedStruct(typeInInterface, []llvm.Value{itfTypeCodeGlobal, itfMethodSetGlobal}))
 		itfConcreteTypeGlobal.SetGlobalConstant(true)
-		itfConcreteTypeGlobal.SetLinkage(llvm.LinkOnceODRLinkage)
+		itfConcreteTypeGlobal.SetLinkage(llvm.PrivateLinkage)
 	}
 	itfTypeCode := b.CreatePtrToInt(itfConcreteTypeGlobal, b.uintptrType, "")
 	itf := llvm.Undef(b.getLLVMRuntimeType("_interface"))
@@ -80,7 +81,7 @@ func (c *compilerContext) getTypeCode(typ types.Type) llvm.Value {
 				globalValue = llvm.ConstInsertValue(globalValue, lengthValue, []uint32{1})
 			}
 			global.SetInitializer(globalValue)
-			global.SetLinkage(llvm.LinkOnceODRLinkage)
+			global.SetLinkage(llvm.PrivateLinkage)
 		}
 		global.SetGlobalConstant(true)
 	}
@@ -235,7 +236,7 @@ func (c *compilerContext) getTypeMethodSet(typ types.Type) llvm.Value {
 		return llvm.ConstGEP(global, []llvm.Value{zero, zero})
 	}
 
-	ms := c.program.MethodSets.MethodSet(typ)
+	ms := c.ir.Program.MethodSets.MethodSet(typ)
 	if ms.Len() == 0 {
 		// no methods, so can leave that one out
 		return llvm.ConstPointerNull(llvm.PointerType(c.getLLVMRuntimeType("interfaceMethodInfo"), 0))
@@ -246,16 +247,15 @@ func (c *compilerContext) getTypeMethodSet(typ types.Type) llvm.Value {
 	for i := 0; i < ms.Len(); i++ {
 		method := ms.At(i)
 		signatureGlobal := c.getMethodSignature(method.Obj().(*types.Func))
-		fn := c.program.MethodValue(method)
-		llvmFn := c.getFunction(fn)
-		if llvmFn.IsNil() {
+		f := c.ir.GetFunction(c.ir.Program.MethodValue(method))
+		if f.LLVMFn.IsNil() {
 			// compiler error, so panic
-			panic("cannot find function: " + c.getFunctionInfo(fn).linkName)
+			panic("cannot find function: " + f.LinkName())
 		}
-		wrapper := c.getInterfaceInvokeWrapper(fn, llvmFn)
+		fn := c.getInterfaceInvokeWrapper(f)
 		methodInfo := llvm.ConstNamedStruct(interfaceMethodInfoType, []llvm.Value{
 			signatureGlobal,
-			llvm.ConstPtrToInt(wrapper, c.uintptrType),
+			llvm.ConstPtrToInt(fn, c.uintptrType),
 		})
 		methods[i] = methodInfo
 	}
@@ -264,7 +264,7 @@ func (c *compilerContext) getTypeMethodSet(typ types.Type) llvm.Value {
 	global = llvm.AddGlobal(c.mod, arrayType, typ.String()+"$methodset")
 	global.SetInitializer(value)
 	global.SetGlobalConstant(true)
-	global.SetLinkage(llvm.LinkOnceODRLinkage)
+	global.SetLinkage(llvm.PrivateLinkage)
 	return llvm.ConstGEP(global, []llvm.Value{zero, zero})
 }
 
@@ -295,7 +295,7 @@ func (c *compilerContext) getInterfaceMethodSet(typ types.Type) llvm.Value {
 	global = llvm.AddGlobal(c.mod, value.Type(), name+"$interface")
 	global.SetInitializer(value)
 	global.SetGlobalConstant(true)
-	global.SetLinkage(llvm.LinkOnceODRLinkage)
+	global.SetLinkage(llvm.PrivateLinkage)
 	return llvm.ConstGEP(global, []llvm.Value{zero, zero})
 }
 
@@ -303,7 +303,7 @@ func (c *compilerContext) getInterfaceMethodSet(typ types.Type) llvm.Value {
 // external *i8 indicating the indicating the signature of this method. It is
 // used during the interface lowering pass.
 func (c *compilerContext) getMethodSignature(method *types.Func) llvm.Value {
-	signature := methodSignature(method)
+	signature := ir.MethodSignature(method)
 	signatureGlobal := c.mod.NamedGlobal("func " + signature)
 	if signatureGlobal.IsNil() {
 		signatureGlobal = llvm.AddGlobal(c.mod, c.ctx.Int8Type(), "func "+signature)
@@ -357,8 +357,8 @@ func (b *builder) createTypeAssert(expr *ssa.TypeAssert) llvm.Value {
 	// value.
 
 	prevBlock := b.GetInsertBlock()
-	okBlock := b.ctx.AddBasicBlock(b.llvmFn, "typeassert.ok")
-	nextBlock := b.ctx.AddBasicBlock(b.llvmFn, "typeassert.next")
+	okBlock := b.ctx.AddBasicBlock(b.fn.LLVMFn, "typeassert.ok")
+	nextBlock := b.ctx.AddBasicBlock(b.fn.LLVMFn, "typeassert.next")
 	b.blockExits[b.currentBlock] = nextBlock // adjust outgoing block for phi nodes
 	b.CreateCondBr(commaOk, okBlock, nextBlock)
 
@@ -436,8 +436,8 @@ func (b *builder) getInvokeCall(instr *ssa.CallCommon) (llvm.Value, []llvm.Value
 // value, dereferences or unpacks it if necessary, and calls the real method.
 // If the method to wrap has a pointer receiver, no wrapping is necessary and
 // the function is returned directly.
-func (c *compilerContext) getInterfaceInvokeWrapper(fn *ssa.Function, llvmFn llvm.Value) llvm.Value {
-	wrapperName := llvmFn.Name() + "$invoke"
+func (c *compilerContext) getInterfaceInvokeWrapper(f *ir.Function) llvm.Value {
+	wrapperName := f.LinkName() + "$invoke"
 	wrapper := c.mod.NamedFunction(wrapperName)
 	if !wrapper.IsNil() {
 		// Wrapper already created. Return it directly.
@@ -445,7 +445,7 @@ func (c *compilerContext) getInterfaceInvokeWrapper(fn *ssa.Function, llvmFn llv
 	}
 
 	// Get the expanded receiver type.
-	receiverType := c.getLLVMType(fn.Signature.Recv().Type())
+	receiverType := c.getLLVMType(f.Params[0].Type())
 	var expandedReceiverType []llvm.Type
 	for _, info := range expandFormalParamType(receiverType, "", nil) {
 		expandedReceiverType = append(expandedReceiverType, info.llvmType)
@@ -457,17 +457,17 @@ func (c *compilerContext) getInterfaceInvokeWrapper(fn *ssa.Function, llvmFn llv
 		// Casting a function signature to a different signature and calling it
 		// with a receiver pointer bitcasted to *i8 (as done in calls on an
 		// interface) is hopefully a safe (defined) operation.
-		return llvmFn
+		return f.LLVMFn
 	}
 
 	// create wrapper function
-	fnType := llvmFn.Type().ElementType()
+	fnType := f.LLVMFn.Type().ElementType()
 	paramTypes := append([]llvm.Type{c.i8ptrType}, fnType.ParamTypes()[len(expandedReceiverType):]...)
 	wrapFnType := llvm.FunctionType(fnType.ReturnType(), paramTypes, false)
 	wrapper = llvm.AddFunction(c.mod, wrapperName, wrapFnType)
 	wrapper.LastParam().SetName("parentHandle")
 
-	wrapper.SetLinkage(llvm.LinkOnceODRLinkage)
+	wrapper.SetLinkage(llvm.InternalLinkage)
 	wrapper.SetUnnamedAddr(true)
 
 	// Create a new builder just to create this wrapper.
@@ -478,9 +478,9 @@ func (c *compilerContext) getInterfaceInvokeWrapper(fn *ssa.Function, llvmFn llv
 	defer b.Builder.Dispose()
 
 	// add debug info if needed
-	if c.Debug {
-		pos := c.program.Fset.Position(fn.Pos())
-		difunc := c.attachDebugInfoRaw(fn, wrapper, "$invoke", pos.Filename, pos.Line)
+	if c.Debug() {
+		pos := c.ir.Program.Fset.Position(f.Pos())
+		difunc := c.attachDebugInfoRaw(f, wrapper, "$invoke", pos.Filename, pos.Line)
 		b.SetCurrentDebugLocation(uint(pos.Line), uint(pos.Column), difunc, llvm.Metadata{})
 	}
 
@@ -490,60 +490,13 @@ func (c *compilerContext) getInterfaceInvokeWrapper(fn *ssa.Function, llvmFn llv
 
 	receiverValue := b.emitPointerUnpack(wrapper.Param(0), []llvm.Type{receiverType})[0]
 	params := append(b.expandFormalParam(receiverValue), wrapper.Params()[1:]...)
-	if llvmFn.Type().ElementType().ReturnType().TypeKind() == llvm.VoidTypeKind {
-		b.CreateCall(llvmFn, params, "")
+	if f.LLVMFn.Type().ElementType().ReturnType().TypeKind() == llvm.VoidTypeKind {
+		b.CreateCall(f.LLVMFn, params, "")
 		b.CreateRetVoid()
 	} else {
-		ret := b.CreateCall(llvmFn, params, "ret")
+		ret := b.CreateCall(f.LLVMFn, params, "ret")
 		b.CreateRet(ret)
 	}
 
 	return wrapper
 }
-
-// methodSignature creates a readable version of a method signature (including
-// the function name, excluding the receiver name). This string is used
-// internally to match interfaces and to call the correct method on an
-// interface. Examples:
-//
-//     String() string
-//     Read([]byte) (int, error)
-func methodSignature(method *types.Func) string {
-	return method.Name() + signature(method.Type().(*types.Signature))
-}
-
-// Make a readable version of a function (pointer) signature.
-// Examples:
-//
-//     () string
-//     (string, int) (int, error)
-func signature(sig *types.Signature) string {
-	s := ""
-	if sig.Params().Len() == 0 {
-		s += "()"
-	} else {
-		s += "("
-		for i := 0; i < sig.Params().Len(); i++ {
-			if i > 0 {
-				s += ", "
-			}
-			s += sig.Params().At(i).Type().String()
-		}
-		s += ")"
-	}
-	if sig.Results().Len() == 0 {
-		// keep as-is
-	} else if sig.Results().Len() == 1 {
-		s += " " + sig.Results().At(0).Type().String()
-	} else {
-		s += " ("
-		for i := 0; i < sig.Results().Len(); i++ {
-			if i > 0 {
-				s += ", "
-			}
-			s += sig.Results().At(i).Type().String()
-		}
-		s += ")"
-	}
-	return s
-}

compiler/interrupt.go

@@ -39,14 +39,14 @@ func (b *builder) createInterruptGlobal(instr *ssa.CallCommon) (llvm.Value, erro
 
 	// Create a new global of type runtime/interrupt.handle. Globals of this
 	// type are lowered in the interrupt lowering pass.
-	globalType := b.program.ImportedPackage("runtime/interrupt").Type("handle").Type()
+	globalType := b.ir.Program.ImportedPackage("runtime/interrupt").Type("handle").Type()
 	globalLLVMType := b.getLLVMType(globalType)
 	globalName := "runtime/interrupt.$interrupt" + strconv.FormatInt(id.Int64(), 10)
 	if global := b.mod.NamedGlobal(globalName); !global.IsNil() {
 		return llvm.Value{}, b.makeError(instr.Pos(), "interrupt redeclared in this program")
 	}
 	global := llvm.AddGlobal(b.mod, globalLLVMType, globalName)
-	global.SetVisibility(llvm.HiddenVisibility)
+	global.SetLinkage(llvm.PrivateLinkage)
 	global.SetGlobalConstant(true)
 	global.SetUnnamedAddr(true)
 	initializer := llvm.ConstNull(globalLLVMType)
@@ -55,8 +55,8 @@ func (b *builder) createInterruptGlobal(instr *ssa.CallCommon) (llvm.Value, erro
 	global.SetInitializer(initializer)
 
 	// Add debug info to the interrupt global.
-	if b.Debug {
-		pos := b.program.Fset.Position(instr.Pos())
+	if b.Debug() {
+		pos := b.ir.Program.Fset.Position(instr.Pos())
 		diglobal := b.dibuilder.CreateGlobalVariableExpression(b.getDIFile(pos.Filename), llvm.DIGlobalVariableExpression{
 			Name:        "interrupt" + strconv.FormatInt(id.Int64(), 10),
 			LinkageName: globalName,
@@ -79,7 +79,7 @@ func (b *builder) createInterruptGlobal(instr *ssa.CallCommon) (llvm.Value, erro
 	// PLIC where each interrupt must be enabled using the interrupt number, and
 	// thus keeps the Interrupt object alive.
 	// This call is removed during interrupt lowering.
-	if strings.HasPrefix(b.Triple, "avr") {
+	if strings.HasPrefix(b.Triple(), "avr") {
 		useFn := b.mod.NamedFunction("runtime/interrupt.use")
 		if useFn.IsNil() {
 			useFnType := llvm.FunctionType(b.ctx.VoidType(), []llvm.Type{interrupt.Type()}, false)

compiler/llvm.go

@@ -44,7 +44,7 @@ func (b *builder) emitLifetimeEnd(ptr, size llvm.Value) {
 // bitcasts, or else allocates a value on the heap if it cannot be packed in the
 // pointer value directly. It returns the pointer with the packed data.
 func (b *builder) emitPointerPack(values []llvm.Value) llvm.Value {
-	return llvmutil.EmitPointerPack(b.Builder, b.mod, b.NeedsStackObjects, values)
+	return llvmutil.EmitPointerPack(b.Builder, b.mod, b.Config, values)
 }
 
 // emitPointerUnpack extracts a list of values packed using emitPointerPack.

compiler/llvmutil/wordpack.go

@@ -5,6 +5,7 @@ package llvmutil
 // itself if possible and legal.
 
 import (
+	"github.com/tinygo-org/tinygo/compileopts"
 	"tinygo.org/x/go-llvm"
 )
 
@@ -12,7 +13,7 @@ import (
 // bitcasts, or else allocates a value on the heap if it cannot be packed in the
 // pointer value directly. It returns the pointer with the packed data.
 // If the values are all constants, they are be stored in a constant global and deduplicated.
-func EmitPointerPack(builder llvm.Builder, mod llvm.Module, needsStackObjects bool, values []llvm.Value) llvm.Value {
+func EmitPointerPack(builder llvm.Builder, mod llvm.Module, config *compileopts.Config, values []llvm.Value) llvm.Value {
 	ctx := mod.Context()
 	targetData := llvm.NewTargetData(mod.DataLayout())
 	i8ptrType := llvm.PointerType(mod.Context().Int8Type(), 0)
@@ -100,7 +101,7 @@ func EmitPointerPack(builder llvm.Builder, mod llvm.Module, needsStackObjects bo
 			llvm.Undef(i8ptrType),            // unused context parameter
 			llvm.ConstPointerNull(i8ptrType), // coroutine handle
 		}, "")
-		if needsStackObjects {
+		if config.NeedsStackObjects() {
 			trackPointer := mod.NamedFunction("runtime.trackPointer")
 			builder.CreateCall(trackPointer, []llvm.Value{
 				packedHeapAlloc,

compiler/symbol.go

@@ -15,298 +15,6 @@ import (
 	"tinygo.org/x/go-llvm"
 )
 
-// functionInfo contains some information about a function or method. In
-// particular, it contains information obtained from pragmas.
-//
-// The linkName value contains a valid link name, even if //go:linkname is not
-// present.
-type functionInfo struct {
-	module     string     // go:wasm-module
-	importName string     // go:linkname, go:export - The name the developer assigns
-	linkName   string     // go:linkname, go:export - The name that we map for the particular module -> importName
-	exported   bool       // go:export, CGo
-	nobounds   bool       // go:nobounds
-	variadic   bool       // go:variadic (CGo only)
-	inline     inlineType // go:inline
-}
-
-type inlineType int
-
-// How much to inline.
-const (
-	// Default behavior. The compiler decides for itself whether any given
-	// function will be inlined. Whether any function is inlined depends on the
-	// optimization level.
-	inlineDefault inlineType = iota
-
-	// Inline hint, just like the C inline keyword (signalled using
-	// //go:inline). The compiler will be more likely to inline this function,
-	// but it is not a guarantee.
-	inlineHint
-
-	// Don't inline, just like the GCC noinline attribute. Signalled using
-	// //go:noinline.
-	inlineNone
-)
-
-// getFunction returns the LLVM function for the given *ssa.Function, creating
-// it if needed. It can later be filled with compilerContext.createFunction().
-func (c *compilerContext) getFunction(fn *ssa.Function) llvm.Value {
-	info := c.getFunctionInfo(fn)
-	llvmFn := c.mod.NamedFunction(info.linkName)
-	if !llvmFn.IsNil() {
-		return llvmFn
-	}
-
-	var retType llvm.Type
-	if fn.Signature.Results() == nil {
-		retType = c.ctx.VoidType()
-	} else if fn.Signature.Results().Len() == 1 {
-		retType = c.getLLVMType(fn.Signature.Results().At(0).Type())
-	} else {
-		results := make([]llvm.Type, 0, fn.Signature.Results().Len())
-		for i := 0; i < fn.Signature.Results().Len(); i++ {
-			results = append(results, c.getLLVMType(fn.Signature.Results().At(i).Type()))
-		}
-		retType = c.ctx.StructType(results, false)
-	}
-
-	var paramInfos []paramInfo
-	for _, param := range getParams(fn.Signature) {
-		paramType := c.getLLVMType(param.Type())
-		paramFragmentInfos := expandFormalParamType(paramType, param.Name(), param.Type())
-		paramInfos = append(paramInfos, paramFragmentInfos...)
-	}
-
-	// Add an extra parameter as the function context. This context is used in
-	// closures and bound methods, but should be optimized away when not used.
-	if !info.exported {
-		paramInfos = append(paramInfos, paramInfo{llvmType: c.i8ptrType, name: "context", flags: 0})
-		paramInfos = append(paramInfos, paramInfo{llvmType: c.i8ptrType, name: "parentHandle", flags: 0})
-	}
-
-	var paramTypes []llvm.Type
-	for _, info := range paramInfos {
-		paramTypes = append(paramTypes, info.llvmType)
-	}
-
-	fnType := llvm.FunctionType(retType, paramTypes, info.variadic)
-	llvmFn = llvm.AddFunction(c.mod, info.linkName, fnType)
-	if strings.HasPrefix(c.Triple, "wasm") {
-		// C functions without prototypes like this:
-		//   void foo();
-		// are actually variadic functions. However, it appears that it has been
-		// decided in WebAssembly that such prototype-less functions are not
-		// allowed in WebAssembly.
-		// In C, this can only happen when there are zero parameters, hence this
-		// check here. For more information:
-		// https://reviews.llvm.org/D48443
-		// https://github.com/WebAssembly/tool-conventions/issues/16
-		if info.variadic && len(fn.Params) == 0 {
-			attr := c.ctx.CreateStringAttribute("no-prototype", "")
-			llvmFn.AddFunctionAttr(attr)
-		}
-	}
-
-	dereferenceableOrNullKind := llvm.AttributeKindID("dereferenceable_or_null")
-	for i, info := range paramInfos {
-		if info.flags&paramIsDeferenceableOrNull == 0 {
-			continue
-		}
-		if info.llvmType.TypeKind() == llvm.PointerTypeKind {
-			el := info.llvmType.ElementType()
-			size := c.targetData.TypeAllocSize(el)
-			if size == 0 {
-				// dereferenceable_or_null(0) appears to be illegal in LLVM.
-				continue
-			}
-			dereferenceableOrNull := c.ctx.CreateEnumAttribute(dereferenceableOrNullKind, size)
-			llvmFn.AddAttributeAtIndex(i+1, dereferenceableOrNull)
-		}
-	}
-
-	// Set a number of function or parameter attributes, depending on the
-	// function. These functions are runtime functions that are known to have
-	// certain attributes that might not be inferred by the compiler.
-	switch info.linkName {
-	case "abort":
-		// On *nix systems, the "abort" functuion in libc is used to handle fatal panics.
-		// Mark it as noreturn so LLVM can optimize away code.
-		llvmFn.AddFunctionAttr(c.ctx.CreateEnumAttribute(llvm.AttributeKindID("noreturn"), 0))
-	case "runtime.alloc":
-		// Tell the optimizer that runtime.alloc is an allocator, meaning that it
-		// returns values that are never null and never alias to an existing value.
-		for _, attrName := range []string{"noalias", "nonnull"} {
-			llvmFn.AddAttributeAtIndex(0, c.ctx.CreateEnumAttribute(llvm.AttributeKindID(attrName), 0))
-		}
-	case "runtime.trackPointer":
-		// This function is necessary for tracking pointers on the stack in a
-		// portable way (see gc_stack_portable.go). Indicate to the optimizer
-		// that the only thing we'll do is read the pointer.
-		llvmFn.AddAttributeAtIndex(1, c.ctx.CreateEnumAttribute(llvm.AttributeKindID("nocapture"), 0))
-		llvmFn.AddAttributeAtIndex(1, c.ctx.CreateEnumAttribute(llvm.AttributeKindID("readonly"), 0))
-	}
-
-	// External/exported functions may not retain pointer values.
-	// https://golang.org/cmd/cgo/#hdr-Passing_pointers
-	if info.exported {
-		// Set the wasm-import-module attribute if the function's module is set.
-		if info.module != "" {
-
-			// We need to add the wasm-import-module and the wasm-import-name
-			wasmImportModuleAttr := c.ctx.CreateStringAttribute("wasm-import-module", info.module)
-			llvmFn.AddFunctionAttr(wasmImportModuleAttr)
-
-			// Add the Wasm Import Name, if we are a named wasm import
-			if info.importName != "" {
-				wasmImportNameAttr := c.ctx.CreateStringAttribute("wasm-import-name", info.importName)
-				llvmFn.AddFunctionAttr(wasmImportNameAttr)
-			}
-		}
-		nocaptureKind := llvm.AttributeKindID("nocapture")
-		nocapture := c.ctx.CreateEnumAttribute(nocaptureKind, 0)
-		for i, typ := range paramTypes {
-			if typ.TypeKind() == llvm.PointerTypeKind {
-				llvmFn.AddAttributeAtIndex(i+1, nocapture)
-			}
-		}
-	}
-
-	// Synthetic functions are functions that do not appear in the source code,
-	// they are artificially constructed. Usually they are wrapper functions
-	// that are not referenced anywhere except in a SSA call instruction so
-	// should be created right away.
-	// The exception is the package initializer, which does appear in the
-	// *ssa.Package members and so shouldn't be created here.
-	if fn.Synthetic != "" && fn.Synthetic != "package initializer" {
-		irbuilder := c.ctx.NewBuilder()
-		b := newBuilder(c, irbuilder, fn)
-		b.createFunction()
-		irbuilder.Dispose()
-		llvmFn.SetLinkage(llvm.LinkOnceODRLinkage)
-		llvmFn.SetUnnamedAddr(true)
-	}
-
-	return llvmFn
-}
-
-// getFunctionInfo returns information about a function that is not directly
-// present in *ssa.Function, such as the link name and whether it should be
-// exported.
-func (c *compilerContext) getFunctionInfo(f *ssa.Function) functionInfo {
-	info := functionInfo{}
-	if strings.HasPrefix(f.Name(), "C.") {
-		// Created by CGo: such a name cannot be created by regular C code.
-		info.linkName = f.Name()[2:]
-		info.exported = true
-	} else {
-		// Pick the default linkName.
-		info.linkName = f.RelString(nil)
-	}
-	// Check for //go: pragmas, which may change the link name (among others).
-	info.parsePragmas(f)
-	return info
-}
-
-// parsePragmas is used by getFunctionInfo to parse function pragmas such as
-// //export or //go:noinline.
-func (info *functionInfo) parsePragmas(f *ssa.Function) {
-	if f.Syntax() == nil {
-		return
-	}
-	if decl, ok := f.Syntax().(*ast.FuncDecl); ok && decl.Doc != nil {
-
-		// Our importName for a wasm module (if we are compiling to wasm), or llvm link name
-		var importName string
-
-		for _, comment := range decl.Doc.List {
-			text := comment.Text
-			if strings.HasPrefix(text, "//export ") {
-				// Rewrite '//export' to '//go:export' for compatibility with
-				// gc.
-				text = "//go:" + text[2:]
-			}
-			if !strings.HasPrefix(text, "//go:") {
-				continue
-			}
-			parts := strings.Fields(text)
-			switch parts[0] {
-			case "//go:export":
-				if len(parts) != 2 {
-					continue
-				}
-
-				importName = parts[1]
-				info.exported = true
-			case "//go:wasm-module":
-				// Alternative comment for setting the import module.
-				if len(parts) != 2 {
-					continue
-				}
-				info.module = parts[1]
-			case "//go:inline":
-				info.inline = inlineHint
-			case "//go:noinline":
-				info.inline = inlineNone
-			case "//go:linkname":
-				if len(parts) != 3 || parts[1] != f.Name() {
-					continue
-				}
-				// Only enable go:linkname when the package imports "unsafe".
-				// This is a slightly looser requirement than what gc uses: gc
-				// requires the file to import "unsafe", not the package as a
-				// whole.
-				if hasUnsafeImport(f.Pkg.Pkg) {
-					info.linkName = parts[2]
-				}
-			case "//go:nobounds":
-				// Skip bounds checking in this function. Useful for some
-				// runtime functions.
-				// This is somewhat dangerous and thus only imported in packages
-				// that import unsafe.
-				if hasUnsafeImport(f.Pkg.Pkg) {
-					info.nobounds = true
-				}
-			case "//go:variadic":
-				// The //go:variadic pragma is emitted by the CGo preprocessing
-				// pass for C variadic functions. This includes both explicit
-				// (with ...) and implicit (no parameters in signature)
-				// functions.
-				if strings.HasPrefix(f.Name(), "C.") {
-					// This prefix cannot naturally be created, it must have
-					// been created as a result of CGo preprocessing.
-					info.variadic = true
-				}
-			}
-		}
-
-		// Set the importName for our exported function if we have one
-		if importName != "" {
-			if info.module == "" {
-				info.linkName = importName
-			} else {
-				// WebAssembly import
-				info.importName = importName
-			}
-		}
-
-	}
-}
-
-// getParams returns the function parameters, including the receiver at the
-// start. This is an alternative to the Params member of *ssa.Function, which is
-// not yet populated when the package has not yet been built.
-func getParams(sig *types.Signature) []*types.Var {
-	params := []*types.Var{}
-	if sig.Recv() != nil {
-		params = append(params, sig.Recv())
-	}
-	for i := 0; i < sig.Params().Len(); i++ {
-		params = append(params, sig.Params().At(i))
-	}
-	return params
-}
-
 // globalInfo contains some information about a specific global. By default,
 // linkName is equal to .RelString(nil) on a global and extern is false, but for
 // some symbols this is different (due to //go:extern for example).
@@ -318,22 +26,25 @@ type globalInfo struct {
 
 // loadASTComments loads comments on globals from the AST, for use later in the
 // program. In particular, they are required for //go:extern pragmas on globals.
-func (c *compilerContext) loadASTComments(pkg *loader.Package) {
-	for _, file := range pkg.Files {
-		for _, decl := range file.Decls {
-			switch decl := decl.(type) {
-			case *ast.GenDecl:
-				switch decl.Tok {
-				case token.VAR:
-					if len(decl.Specs) != 1 {
-						continue
-					}
-					for _, spec := range decl.Specs {
-						switch spec := spec.(type) {
-						case *ast.ValueSpec: // decl.Tok == token.VAR
-							for _, name := range spec.Names {
-								id := pkg.Pkg.Path() + "." + name.Name
-								c.astComments[id] = decl.Doc
+func (c *compilerContext) loadASTComments(lprogram *loader.Program) {
+	c.astComments = map[string]*ast.CommentGroup{}
+	for _, pkgInfo := range lprogram.Sorted() {
+		for _, file := range pkgInfo.Files {
+			for _, decl := range file.Decls {
+				switch decl := decl.(type) {
+				case *ast.GenDecl:
+					switch decl.Tok {
+					case token.VAR:
+						if len(decl.Specs) != 1 {
+							continue
+						}
+						for _, spec := range decl.Specs {
+							switch spec := spec.(type) {
+							case *ast.ValueSpec: // decl.Tok == token.VAR
+								for _, name := range spec.Names {
+									id := pkgInfo.Pkg.Path() + "." + name.Name
+									c.astComments[id] = decl.Doc
+								}
 							}
 						}
 					}
@@ -352,6 +63,10 @@ func (c *compilerContext) getGlobal(g *ssa.Global) llvm.Value {
 		typ := g.Type().(*types.Pointer).Elem()
 		llvmType := c.getLLVMType(typ)
 		llvmGlobal = llvm.AddGlobal(c.mod, llvmType, info.linkName)
+		if !info.extern {
+			llvmGlobal.SetInitializer(llvm.ConstNull(llvmType))
+			llvmGlobal.SetLinkage(llvm.InternalLinkage)
+		}
 
 		// Set alignment from the //go:align comment.
 		var alignInBits uint32
@@ -367,9 +82,11 @@ func (c *compilerContext) getGlobal(g *ssa.Global) llvm.Value {
 			}
 		}
 
-		if c.Debug && !info.extern {
+		if c.Debug() && !info.extern {
 			// Add debug info.
-			pos := c.program.Fset.Position(g.Pos())
+			// TODO: this should be done for every global in the program, not just
+			// the ones that are referenced from some code.
+			pos := c.ir.Program.Fset.Position(g.Pos())
 			diglobal := c.dibuilder.CreateGlobalVariableExpression(c.difiles[pos.Filename], llvm.DIGlobalVariableExpression{
 				Name:        g.RelString(nil),
 				LinkageName: info.linkName,
@@ -428,23 +145,3 @@ func (info *globalInfo) parsePragmas(doc *ast.CommentGroup) {
 		}
 	}
 }
-
-// Get all methods of a type.
-func getAllMethods(prog *ssa.Program, typ types.Type) []*types.Selection {
-	ms := prog.MethodSets.MethodSet(typ)
-	methods := make([]*types.Selection, ms.Len())
-	for i := 0; i < ms.Len(); i++ {
-		methods[i] = ms.At(i)
-	}
-	return methods
-}
-
-// Return true if this package imports "unsafe", false otherwise.
-func hasUnsafeImport(pkg *types.Package) bool {
-	for _, imp := range pkg.Imports() {
-		if imp == types.Unsafe {
-			return true
-		}
-	}
-	return false
-}

compiler/syscall.go

@@ -16,8 +16,8 @@ func (b *builder) createSyscall(call *ssa.CallCommon) (llvm.Value, error) {
 	num := b.getValue(call.Args[0])
 	var syscallResult llvm.Value
 	switch {
-	case b.GOARCH == "amd64":
-		if b.GOOS == "darwin" {
+	case b.GOARCH() == "amd64":
+		if b.GOOS() == "darwin" {
 			// Darwin adds this magic number to system call numbers:
 			//
 			// > Syscall classes for 64-bit system call entry.
@@ -58,7 +58,7 @@ func (b *builder) createSyscall(call *ssa.CallCommon) (llvm.Value, error) {
 		fnType := llvm.FunctionType(b.uintptrType, argTypes, false)
 		target := llvm.InlineAsm(fnType, "syscall", constraints, true, false, llvm.InlineAsmDialectIntel)
 		syscallResult = b.CreateCall(target, args, "")
-	case b.GOARCH == "386" && b.GOOS == "linux":
+	case b.GOARCH() == "386" && b.GOOS() == "linux":
 		// Sources:
 		//   syscall(2) man page
 		//   https://stackoverflow.com/a/2538212
@@ -84,7 +84,7 @@ func (b *builder) createSyscall(call *ssa.CallCommon) (llvm.Value, error) {
 		fnType := llvm.FunctionType(b.uintptrType, argTypes, false)
 		target := llvm.InlineAsm(fnType, "int 0x80", constraints, true, false, llvm.InlineAsmDialectIntel)
 		syscallResult = b.CreateCall(target, args, "")
-	case b.GOARCH == "arm" && b.GOOS == "linux":
+	case b.GOARCH() == "arm" && b.GOOS() == "linux":
 		// Implement the EABI system call convention for Linux.
 		// Source: syscall(2) man page.
 		args := []llvm.Value{}
@@ -116,7 +116,7 @@ func (b *builder) createSyscall(call *ssa.CallCommon) (llvm.Value, error) {
 		fnType := llvm.FunctionType(b.uintptrType, argTypes, false)
 		target := llvm.InlineAsm(fnType, "svc #0", constraints, true, false, 0)
 		syscallResult = b.CreateCall(target, args, "")
-	case b.GOARCH == "arm64" && b.GOOS == "linux":
+	case b.GOARCH() == "arm64" && b.GOOS() == "linux":
 		// Source: syscall(2) man page.
 		args := []llvm.Value{}
 		argTypes := []llvm.Type{}
@@ -149,9 +149,9 @@ func (b *builder) createSyscall(call *ssa.CallCommon) (llvm.Value, error) {
 		target := llvm.InlineAsm(fnType, "svc #0", constraints, true, false, 0)
 		syscallResult = b.CreateCall(target, args, "")
 	default:
-		return llvm.Value{}, b.makeError(call.Pos(), "unknown GOOS/GOARCH for syscall: "+b.GOOS+"/"+b.GOARCH)
+		return llvm.Value{}, b.makeError(call.Pos(), "unknown GOOS/GOARCH for syscall: "+b.GOOS()+"/"+b.GOARCH())
 	}
-	switch b.GOOS {
+	switch b.GOOS() {
 	case "linux", "freebsd":
 		// Return values: r0, r1 uintptr, err Errno
 		// Pseudocode:
@@ -187,6 +187,6 @@ func (b *builder) createSyscall(call *ssa.CallCommon) (llvm.Value, error) {
 		retval = b.CreateInsertValue(retval, errResult, 2, "")
 		return retval, nil
 	default:
-		return llvm.Value{}, b.makeError(call.Pos(), "unknown GOOS/GOARCH for syscall: "+b.GOOS+"/"+b.GOARCH)
+		return llvm.Value{}, b.makeError(call.Pos(), "unknown GOOS/GOARCH for syscall: "+b.GOOS()+"/"+b.GOARCH())
 	}
 }

compiler/testdata/basic.ll

@@ -3,72 +3,70 @@ source_filename = "basic.go"
 target datalayout = "e-m:e-p:32:32-p270:32:32-p271:32:32-p272:64:64-f64:32:64-f80:32-n8:16:32-S128"
 target triple = "i686--linux"
 
-declare noalias nonnull i8* @runtime.alloc(i32, i8*, i8*)
-
-define hidden void @main.init(i8* %context, i8* %parentHandle) unnamed_addr {
+define internal void @main.init(i8* %context, i8* %parentHandle) unnamed_addr {
 entry:
   ret void
 }
 
-define hidden i32 @main.addInt(i32 %x, i32 %y, i8* %context, i8* %parentHandle) unnamed_addr {
+define internal i32 @main.addInt(i32 %x, i32 %y, i8* %context, i8* %parentHandle) unnamed_addr {
 entry:
   %0 = add i32 %x, %y
   ret i32 %0
 }
 
-define hidden i1 @main.equalInt(i32 %x, i32 %y, i8* %context, i8* %parentHandle) unnamed_addr {
+define internal i1 @main.equalInt(i32 %x, i32 %y, i8* %context, i8* %parentHandle) unnamed_addr {
 entry:
   %0 = icmp eq i32 %x, %y
   ret i1 %0
 }
 
-define hidden i1 @main.floatEQ(float %x, float %y, i8* %context, i8* %parentHandle) unnamed_addr {
+define internal i1 @main.floatEQ(float %x, float %y, i8* %context, i8* %parentHandle) unnamed_addr {
 entry:
   %0 = fcmp oeq float %x, %y
   ret i1 %0
 }
 
-define hidden i1 @main.floatNE(float %x, float %y, i8* %context, i8* %parentHandle) unnamed_addr {
+define internal i1 @main.floatNE(float %x, float %y, i8* %context, i8* %parentHandle) unnamed_addr {
 entry:
   %0 = fcmp une float %x, %y
   ret i1 %0
 }
 
-define hidden i1 @main.floatLower(float %x, float %y, i8* %context, i8* %parentHandle) unnamed_addr {
+define internal i1 @main.floatLower(float %x, float %y, i8* %context, i8* %parentHandle) unnamed_addr {
 entry:
   %0 = fcmp olt float %x, %y
   ret i1 %0
 }
 
-define hidden i1 @main.floatLowerEqual(float %x, float %y, i8* %context, i8* %parentHandle) unnamed_addr {
+define internal i1 @main.floatLowerEqual(float %x, float %y, i8* %context, i8* %parentHandle) unnamed_addr {
 entry:
   %0 = fcmp ole float %x, %y
   ret i1 %0
 }
 
-define hidden i1 @main.floatGreater(float %x, float %y, i8* %context, i8* %parentHandle) unnamed_addr {
+define internal i1 @main.floatGreater(float %x, float %y, i8* %context, i8* %parentHandle) unnamed_addr {
 entry:
   %0 = fcmp ogt float %x, %y
   ret i1 %0
 }
 
-define hidden i1 @main.floatGreaterEqual(float %x, float %y, i8* %context, i8* %parentHandle) unnamed_addr {
+define internal i1 @main.floatGreaterEqual(float %x, float %y, i8* %context, i8* %parentHandle) unnamed_addr {
 entry:
   %0 = fcmp oge float %x, %y
   ret i1 %0
 }
 
-define hidden float @main.complexReal(float %x.r, float %x.i, i8* %context, i8* %parentHandle) unnamed_addr {
+define internal float @main.complexReal(float %x.r, float %x.i, i8* %context, i8* %parentHandle) unnamed_addr {
 entry:
   ret float %x.r
 }
 
-define hidden float @main.complexImag(float %x.r, float %x.i, i8* %context, i8* %parentHandle) unnamed_addr {
+define internal float @main.complexImag(float %x.r, float %x.i, i8* %context, i8* %parentHandle) unnamed_addr {
 entry:
   ret float %x.i
 }
 
-define hidden { float, float } @main.complexAdd(float %x.r, float %x.i, float %y.r, float %y.i, i8* %context, i8* %parentHandle) unnamed_addr {
+define internal { float, float } @main.complexAdd(float %x.r, float %x.i, float %y.r, float %y.i, i8* %context, i8* %parentHandle) unnamed_addr {
 entry:
   %0 = fadd float %x.r, %y.r
   %1 = fadd float %x.i, %y.i
@@ -77,7 +75,7 @@ entry:
   ret { float, float } %3
 }
 
-define hidden { float, float } @main.complexSub(float %x.r, float %x.i, float %y.r, float %y.i, i8* %context, i8* %parentHandle) unnamed_addr {
+define internal { float, float } @main.complexSub(float %x.r, float %x.i, float %y.r, float %y.i, i8* %context, i8* %parentHandle) unnamed_addr {
 entry:
   %0 = fsub float %x.r, %y.r
   %1 = fsub float %x.i, %y.i
@@ -86,7 +84,7 @@ entry:
   ret { float, float } %3
 }
 
-define hidden { float, float } @main.complexMul(float %x.r, float %x.i, float %y.r, float %y.i, i8* %context, i8* %parentHandle) unnamed_addr {
+define internal { float, float } @main.complexMul(float %x.r, float %x.i, float %y.r, float %y.i, i8* %context, i8* %parentHandle) unnamed_addr {
 entry:
   %0 = fmul float %x.r, %y.r
   %1 = fmul float %x.i, %y.i

compiler/testdata/float.go

@@ -1,39 +0,0 @@
-package main
-
-// Test converting floats to ints.
-
-func f32tou32(v float32) uint32 {
-	return uint32(v)
-}
-
-func maxu32f() float32 {
-	return float32(^uint32(0))
-}
-
-func maxu32tof32() uint32 {
-	f := float32(^uint32(0))
-	return uint32(f)
-}
-
-func inftoi32() (uint32, uint32, int32, int32) {
-	inf := 1.0
-	inf /= 0.0
-
-	return uint32(inf), uint32(-inf), int32(inf), int32(-inf)
-}
-
-func u32tof32tou32(v uint32) uint32 {
-	return uint32(float32(v))
-}
-
-func f32tou32tof32(v float32) float32 {
-	return float32(uint32(v))
-}
-
-func f32tou8(v float32) uint8 {
-	return uint8(v)
-}
-
-func f32toi8(v float32) int8 {
-	return int8(v)
-}

compiler/testdata/float.ll

@@ -1,82 +0,0 @@
-; ModuleID = 'float.go'
-source_filename = "float.go"
-target datalayout = "e-m:e-p:32:32-p270:32:32-p271:32:32-p272:64:64-f64:32:64-f80:32-n8:16:32-S128"
-target triple = "i686--linux"
-
-declare noalias nonnull i8* @runtime.alloc(i32, i8*, i8*)
-
-define hidden void @main.init(i8* %context, i8* %parentHandle) unnamed_addr {
-entry:
-  ret void
-}
-
-define hidden i32 @main.f32tou32(float %v, i8* %context, i8* %parentHandle) unnamed_addr {
-entry:
-  %positive = fcmp oge float %v, 0.000000e+00
-  %withinmax = fcmp ole float %v, 0x41EFFFFFC0000000
-  %inbounds = and i1 %positive, %withinmax
-  %saturated = sext i1 %positive to i32
-  %normal = fptoui float %v to i32
-  %0 = select i1 %inbounds, i32 %normal, i32 %saturated
-  ret i32 %0
-}
-
-define hidden float @main.maxu32f(i8* %context, i8* %parentHandle) unnamed_addr {
-entry:
-  ret float 0x41F0000000000000
-}
-
-define hidden i32 @main.maxu32tof32(i8* %context, i8* %parentHandle) unnamed_addr {
-entry:
-  ret i32 -1
-}
-
-define hidden { i32, i32, i32, i32 } @main.inftoi32(i8* %context, i8* %parentHandle) unnamed_addr {
-entry:
-  ret { i32, i32, i32, i32 } { i32 -1, i32 0, i32 2147483647, i32 -2147483648 }
-}
-
-define hidden i32 @main.u32tof32tou32(i32 %v, i8* %context, i8* %parentHandle) unnamed_addr {
-entry:
-  %0 = uitofp i32 %v to float
-  %withinmax = fcmp ole float %0, 0x41EFFFFFC0000000
-  %normal = fptoui float %0 to i32
-  %1 = select i1 %withinmax, i32 %normal, i32 -1
-  ret i32 %1
-}
-
-define hidden float @main.f32tou32tof32(float %v, i8* %context, i8* %parentHandle) unnamed_addr {
-entry:
-  %positive = fcmp oge float %v, 0.000000e+00
-  %withinmax = fcmp ole float %v, 0x41EFFFFFC0000000
-  %inbounds = and i1 %positive, %withinmax
-  %saturated = sext i1 %positive to i32
-  %normal = fptoui float %v to i32
-  %0 = select i1 %inbounds, i32 %normal, i32 %saturated
-  %1 = uitofp i32 %0 to float
-  ret float %1
-}
-
-define hidden i8 @main.f32tou8(float %v, i8* %context, i8* %parentHandle) unnamed_addr {
-entry:
-  %positive = fcmp oge float %v, 0.000000e+00
-  %withinmax = fcmp ole float %v, 2.550000e+02
-  %inbounds = and i1 %positive, %withinmax
-  %saturated = sext i1 %positive to i8
-  %normal = fptoui float %v to i8
-  %0 = select i1 %inbounds, i8 %normal, i8 %saturated
-  ret i8 %0
-}
-
-define hidden i8 @main.f32toi8(float %v, i8* %context, i8* %parentHandle) unnamed_addr {
-entry:
-  %abovemin = fcmp oge float %v, -1.280000e+02
-  %belowmax = fcmp ole float %v, 1.270000e+02
-  %inbounds = and i1 %abovemin, %belowmax
-  %saturated = select i1 %abovemin, i8 127, i8 -128
-  %isnan = fcmp uno float %v, 0.000000e+00
-  %remapped = select i1 %isnan, i8 0, i8 %saturated
-  %normal = fptosi float %v to i8
-  %0 = select i1 %inbounds, i8 %normal, i8 %remapped
-  ret i8 %0
-}

compiler/testdata/pointer.ll

@@ -3,48 +3,46 @@ source_filename = "pointer.go"
 target datalayout = "e-m:e-p:32:32-p270:32:32-p271:32:32-p272:64:64-f64:32:64-f80:32-n8:16:32-S128"
 target triple = "i686--linux"
 
-declare noalias nonnull i8* @runtime.alloc(i32, i8*, i8*)
-
-define hidden void @main.init(i8* %context, i8* %parentHandle) unnamed_addr {
+define internal void @main.init(i8* %context, i8* %parentHandle) unnamed_addr {
 entry:
   ret void
 }
 
-define hidden [0 x i32] @main.pointerDerefZero([0 x i32]* %x, i8* %context, i8* %parentHandle) unnamed_addr {
+define internal [0 x i32] @main.pointerDerefZero([0 x i32]* %x, i8* %context, i8* %parentHandle) unnamed_addr {
 entry:
   ret [0 x i32] zeroinitializer
 }
 
-define hidden i32* @main.pointerCastFromUnsafe(i8* %x, i8* %context, i8* %parentHandle) unnamed_addr {
+define internal i32* @main.pointerCastFromUnsafe(i8* %x, i8* %context, i8* %parentHandle) unnamed_addr {
 entry:
   %0 = bitcast i8* %x to i32*
   ret i32* %0
 }
 
-define hidden i8* @main.pointerCastToUnsafe(i32* dereferenceable_or_null(4) %x, i8* %context, i8* %parentHandle) unnamed_addr {
+define internal i8* @main.pointerCastToUnsafe(i32* dereferenceable_or_null(4) %x, i8* %context, i8* %parentHandle) unnamed_addr {
 entry:
   %0 = bitcast i32* %x to i8*
   ret i8* %0
 }
 
-define hidden i8* @main.pointerCastToUnsafeNoop(i8* dereferenceable_or_null(1) %x, i8* %context, i8* %parentHandle) unnamed_addr {
+define internal i8* @main.pointerCastToUnsafeNoop(i8* dereferenceable_or_null(1) %x, i8* %context, i8* %parentHandle) unnamed_addr {
 entry:
   ret i8* %x
 }
 
-define hidden i8* @main.pointerUnsafeGEPFixedOffset(i8* dereferenceable_or_null(1) %ptr, i8* %context, i8* %parentHandle) unnamed_addr {
+define internal i8* @main.pointerUnsafeGEPFixedOffset(i8* dereferenceable_or_null(1) %ptr, i8* %context, i8* %parentHandle) unnamed_addr {
 entry:
   %0 = getelementptr inbounds i8, i8* %ptr, i32 10
   ret i8* %0
 }
 
-define hidden i8* @main.pointerUnsafeGEPByteOffset(i8* dereferenceable_or_null(1) %ptr, i32 %offset, i8* %context, i8* %parentHandle) unnamed_addr {
+define internal i8* @main.pointerUnsafeGEPByteOffset(i8* dereferenceable_or_null(1) %ptr, i32 %offset, i8* %context, i8* %parentHandle) unnamed_addr {
 entry:
   %0 = getelementptr inbounds i8, i8* %ptr, i32 %offset
   ret i8* %0
 }
 
-define hidden i32* @main.pointerUnsafeGEPIntOffset(i32* dereferenceable_or_null(4) %ptr, i32 %offset, i8* %context, i8* %parentHandle) unnamed_addr {
+define internal i32* @main.pointerUnsafeGEPIntOffset(i32* dereferenceable_or_null(4) %ptr, i32 %offset, i8* %context, i8* %parentHandle) unnamed_addr {
 entry:
   %0 = getelementptr i32, i32* %ptr, i32 %offset
   ret i32* %0

compiler/testdata/slice.ll

@@ -3,19 +3,17 @@ source_filename = "slice.go"
 target datalayout = "e-m:e-p:32:32-p270:32:32-p271:32:32-p272:64:64-f64:32:64-f80:32-n8:16:32-S128"
 target triple = "i686--linux"
 
-declare noalias nonnull i8* @runtime.alloc(i32, i8*, i8*)
-
-define hidden void @main.init(i8* %context, i8* %parentHandle) unnamed_addr {
+define internal void @main.init(i8* %context, i8* %parentHandle) unnamed_addr {
 entry:
   ret void
 }
 
-define hidden i32 @main.sliceLen(i32* %ints.data, i32 %ints.len, i32 %ints.cap, i8* %context, i8* %parentHandle) unnamed_addr {
+define internal i32 @main.sliceLen(i32* %ints.data, i32 %ints.len, i32 %ints.cap, i8* %context, i8* %parentHandle) unnamed_addr {
 entry:
   ret i32 %ints.len
 }
 
-define hidden i32 @main.sliceCap(i32* %ints.data, i32 %ints.len, i32 %ints.cap, i8* %context, i8* %parentHandle) unnamed_addr {
+define internal i32 @main.sliceCap(i32* %ints.data, i32 %ints.len, i32 %ints.cap, i8* %context, i8* %parentHandle) unnamed_addr {
 entry:
   ret i32 %ints.cap
 }

go.mod

@@ -1,16 +1,14 @@
 module github.com/tinygo-org/tinygo
 
-go 1.13
+go 1.11
 
 require (
 	github.com/blakesmith/ar v0.0.0-20150311145944-8bd4349a67f2
-	github.com/chromedp/cdproto v0.0.0-20210113043257-dabd2f2e7693
-	github.com/chromedp/chromedp v0.6.4
+	github.com/chromedp/cdproto v0.0.0-20200709115526-d1f6fc58448b
+	github.com/chromedp/chromedp v0.5.4-0.20200303084119-2bb39134ab9e
 	github.com/google/shlex v0.0.0-20181106134648-c34317bd91bf
 	github.com/marcinbor85/gohex v0.0.0-20200531091804-343a4b548892
-	github.com/mattn/go-colorable v0.1.8
-	go.bug.st/serial v1.1.2
-	golang.org/x/sys v0.0.0-20210113181707-4bcb84eeeb78
+	go.bug.st/serial v1.0.0
 	golang.org/x/tools v0.0.0-20200216192241-b320d3a0f5a2
-	tinygo.org/x/go-llvm v0.0.0-20210308112806-9ef958b6bed4
+	tinygo.org/x/go-llvm v0.0.0-20201104183921-570e7a6841d9
 )

go.sum

@@ -1,39 +1,33 @@
 github.com/blakesmith/ar v0.0.0-20150311145944-8bd4349a67f2 h1:oMCHnXa6CCCafdPDbMh/lWRhRByN0VFLvv+g+ayx1SI=
 github.com/blakesmith/ar v0.0.0-20150311145944-8bd4349a67f2/go.mod h1:PkYb9DJNAwrSvRx5DYA+gUcOIgTGVMNkfSCbZM8cWpI=
-github.com/chromedp/cdproto v0.0.0-20210113043257-dabd2f2e7693 h1:11eq/RkpaotwdF6b1TRMcdgQUPNmyFEJOB7zLvh0O/Y=
-github.com/chromedp/cdproto v0.0.0-20210113043257-dabd2f2e7693/go.mod h1:55pim6Ht4LJKdVLlyFJV/g++HsEA1hQxPbB5JyNdZC0=
-github.com/chromedp/chromedp v0.6.4 h1:Gx7ZkRyrSVmbbDDja/ieNgNGJIvElroPOyeqYQGVDSY=
-github.com/chromedp/chromedp v0.6.4/go.mod h1:vodUdJf5dF/b8n0UBJv6NeM/QK28RjP3j+eM7fq4+84=
-github.com/chromedp/sysutil v1.0.0 h1:+ZxhTpfpZlmchB58ih/LBHX52ky7w2VhQVKQMucy3Ic=
-github.com/chromedp/sysutil v1.0.0/go.mod h1:kgWmDdq8fTzXYcKIBqIYvRRTnYb9aNS9moAV0xufSww=
+github.com/chromedp/cdproto v0.0.0-20200116234248-4da64dd111ac/go.mod h1:PfAWWKJqjlGFYJEidUM6aVIWPr0EpobeyVWEEmplX7g=
+github.com/chromedp/cdproto v0.0.0-20200709115526-d1f6fc58448b h1:LF+GRwyzxrO3MUzPvejv+yBup0lNG+/QdIRrkxOPseA=
+github.com/chromedp/cdproto v0.0.0-20200709115526-d1f6fc58448b/go.mod h1:E6LPWRdIJc11h/di5p0rwvRmUYbhGpBEH7ZbPfzDIOE=
+github.com/chromedp/chromedp v0.5.4-0.20200303084119-2bb39134ab9e h1:Hv0JVyHhbIXb9NiYQe4NsrfgrSofAp0q2FnhhJOXgi8=
+github.com/chromedp/chromedp v0.5.4-0.20200303084119-2bb39134ab9e/go.mod h1:vmQMRHFZrY3T+Jv51T0n87OK/i6bK+5P9a+Fg5jPwgQ=
 github.com/creack/goselect v0.1.1 h1:tiSSgKE1eJtxs1h/VgGQWuXUP0YS4CDIFMp6vaI1ls0=
 github.com/creack/goselect v0.1.1/go.mod h1:a/NhLweNvqIYMuxcMOuWY516Cimucms3DglDzQP3hKY=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
-github.com/gobwas/httphead v0.1.0 h1:exrUm0f4YX0L7EBwZHuCF4GDp8aJfVeBrlLQrs6NqWU=
-github.com/gobwas/httphead v0.1.0/go.mod h1:O/RXo79gxV8G+RqlR/otEwx4Q36zl9rqC5u12GKvMCM=
-github.com/gobwas/pool v0.2.1 h1:xfeeEhW7pwmX8nuLVlqbzVc7udMDrwetjEv+TZIz1og=
-github.com/gobwas/pool v0.2.1/go.mod h1:q8bcK0KcYlCgd9e7WYLm9LpyS+YeLd8JVDW6WezmKEw=
-github.com/gobwas/ws v1.0.4 h1:5eXU1CZhpQdq5kXbKb+sECH5Ia5KiO6CYzIzdlVx6Bs=
-github.com/gobwas/ws v1.0.4/go.mod h1:szmBTxLgaFppYjEmNtny/v3w89xOydFnnZMcgRRu/EM=
+github.com/gobwas/httphead v0.0.0-20180130184737-2c6c146eadee h1:s+21KNqlpePfkah2I+gwHF8xmJWRjooY+5248k6m4A0=
+github.com/gobwas/httphead v0.0.0-20180130184737-2c6c146eadee/go.mod h1:L0fX3K22YWvt/FAX9NnzrNzcI4wNYi9Yku4O0LKYflo=
+github.com/gobwas/pool v0.2.0 h1:QEmUOlnSjWtnpRGHF3SauEiOsy82Cup83Vf2LcMlnc8=
+github.com/gobwas/pool v0.2.0/go.mod h1:q8bcK0KcYlCgd9e7WYLm9LpyS+YeLd8JVDW6WezmKEw=
+github.com/gobwas/ws v1.0.3 h1:ZOigqf7iBxkA4jdQ3am7ATzdlOFp9YzA6NmuvEEZc9g=
+github.com/gobwas/ws v1.0.3/go.mod h1:szmBTxLgaFppYjEmNtny/v3w89xOydFnnZMcgRRu/EM=
 github.com/google/shlex v0.0.0-20181106134648-c34317bd91bf h1:7+FW5aGwISbqUtkfmIpZJGRgNFg2ioYPvFaUxdqpDsg=
 github.com/google/shlex v0.0.0-20181106134648-c34317bd91bf/go.mod h1:RpwtwJQFrIEPstU94h88MWPXP2ektJZ8cZ0YntAmXiE=
-github.com/josharian/intern v1.0.0 h1:vlS4z54oSdjm0bgjRigI+G1HpF+tI+9rE5LLzOg8HmY=
-github.com/josharian/intern v1.0.0/go.mod h1:5DoeVV0s6jJacbCEi61lwdGj/aVlrQvzHFFd8Hwg//Y=
-github.com/mailru/easyjson v0.7.6 h1:8yTIVnZgCoiM1TgqoeTl+LfU5Jg6/xL3QhGQnimLYnA=
-github.com/mailru/easyjson v0.7.6/go.mod h1:xzfreul335JAWq5oZzymOObrkdz5UnU4kGfJJLY9Nlc=
+github.com/knq/sysutil v0.0.0-20191005231841-15668db23d08 h1:V0an7KRw92wmJysvFvtqtKMAPmvS5O0jtB0nYo6t+gs=
+github.com/knq/sysutil v0.0.0-20191005231841-15668db23d08/go.mod h1:dFWs1zEqDjFtnBXsd1vPOZaLsESovai349994nHx3e0=
+github.com/mailru/easyjson v0.7.0/go.mod h1:KAzv3t3aY1NaHWoQz1+4F1ccyAH66Jk7yos7ldAVICs=
+github.com/mailru/easyjson v0.7.1 h1:mdxE1MF9o53iCb2Ghj1VfWvh7ZOwHpnVG/xwXrV90U8=
+github.com/mailru/easyjson v0.7.1/go.mod h1:KAzv3t3aY1NaHWoQz1+4F1ccyAH66Jk7yos7ldAVICs=
 github.com/marcinbor85/gohex v0.0.0-20200531091804-343a4b548892 h1:6J+qramlHVLmiBOgRiBOnQkno8uprqG6YFFQTt6uYIw=
 github.com/marcinbor85/gohex v0.0.0-20200531091804-343a4b548892/go.mod h1:Pb6XcsXyropB9LNHhnqaknG/vEwYztLkQzVCHv8sQ3M=
-github.com/mattn/go-colorable v0.1.8 h1:c1ghPdyEDarC70ftn0y+A/Ee++9zz8ljHG1b13eJ0s8=
-github.com/mattn/go-colorable v0.1.8/go.mod h1:u6P/XSegPjTcexA+o6vUJrdnUu04hMope9wVRipJSqc=
-github.com/mattn/go-isatty v0.0.12 h1:wuysRhFDzyxgEmMf5xjvJ2M9dZoWAXNNr5LSBS7uHXY=
-github.com/mattn/go-isatty v0.0.12/go.mod h1:cbi8OIDigv2wuxKPP5vlRcQ1OAZbq2CE4Kysco4FUpU=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
 go.bug.st/serial v1.0.0 h1:ogEPzrllCsnG00EqKRjeYvPRsO7NJW6DqykzkdD6E/k=
 go.bug.st/serial v1.0.0/go.mod h1:rpXPISGjuNjPTRTcMlxi9lN6LoIPxd1ixVjBd8aSk/Q=
-go.bug.st/serial v1.1.2 h1:6xDpbta8KJ+VLRTeM8ghhxXRMLE/Lr8h9iDKwydarAY=
-go.bug.st/serial v1.1.2/go.mod h1:VmYBeyJWp5BnJ0tw2NUJHZdJTGl2ecBGABHlzRK1knY=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
 golang.org/x/mod v0.1.1-0.20191105210325-c90efee705ee h1:WG0RUwxtNT4qqaXX3DPA8zHFNm/D9xaBpxzHt1WcA/E=
@@ -45,11 +39,8 @@ golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5h
 golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20191128015809-6d18c012aee9 h1:ZBzSG/7F4eNKz2L3GE9o300RX0Az1Bw5HF7PDraD+qU=
 golang.org/x/sys v0.0.0-20191128015809-6d18c012aee9/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20200116001909-b77594299b42 h1:vEOn+mP2zCOVzKckCZy6YsCtDblrpj/w7B9nxGNELpg=
 golang.org/x/sys v0.0.0-20200116001909-b77594299b42/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20200223170610-d5e6a3e2c0ae/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20200909081042-eff7692f9009/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20210113181707-4bcb84eeeb78 h1:nVuTkr9L6Bq62qpUqKo/RnZCFfzDBL0bYo6w9OJUqZY=
-golang.org/x/sys v0.0.0-20210113181707-4bcb84eeeb78/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/tools v0.0.0-20200216192241-b320d3a0f5a2 h1:0sfSpGSa544Fwnbot3Oxq/U6SXqjty6Jy/3wRhVS7ig=
 golang.org/x/tools v0.0.0-20200216192241-b320d3a0f5a2/go.mod h1:TB2adYChydJhpapKDTa4BR/hXlZSLoq2Wpct/0txZ28=
@@ -57,5 +48,5 @@ golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898 h1:/atklqdjdhuosWIl6AIbO
 golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
-tinygo.org/x/go-llvm v0.0.0-20210308112806-9ef958b6bed4 h1:CMUHxVTb+UuUePuMf8vkWjZ3gTp9BBK91KrgOCwoNHs=
-tinygo.org/x/go-llvm v0.0.0-20210308112806-9ef958b6bed4/go.mod h1:fv1F0BSNpxMfCL0zF3M4OPFbgYHnhtB6ST0HvUtu/LE=
+tinygo.org/x/go-llvm v0.0.0-20201104183921-570e7a6841d9 h1:l2kTQOhqEoeDTK3ckUnwReOQwMPUmURMIdjJbeAuDT4=
+tinygo.org/x/go-llvm v0.0.0-20201104183921-570e7a6841d9/go.mod h1:fv1F0BSNpxMfCL0zF3M4OPFbgYHnhtB6ST0HvUtu/LE=

goenv/goenv.go

@@ -142,11 +142,10 @@ func getHomeDir() string {
 // getGoroot returns an appropriate GOROOT from various sources. If it can't be
 // found, it returns an empty string.
 func getGoroot() string {
-	// An explicitly set GOROOT always has preference.
 	goroot := os.Getenv("GOROOT")
 	if goroot != "" {
-		// Convert to the standard GOROOT being referenced, if it's a TinyGo cache.
-		return getStandardGoroot(goroot)
+		// An explicitly set GOROOT always has preference.
+		return goroot
 	}
 
 	// Check for the location of the 'go' binary and base GOROOT on that.
@@ -196,21 +195,3 @@ func isGoroot(goroot string) bool {
 	_, err := os.Stat(filepath.Join(goroot, "src", "runtime", "internal", "sys", "zversion.go"))
 	return err == nil
 }
-
-// getStandardGoroot returns the physical path to a real, standard Go GOROOT
-// implied by the given path.
-// If the given path appears to be a TinyGo cached GOROOT, it returns the path
-// referenced by symlinks contained in the cache. Otherwise, it returns the
-// given path as-is.
-func getStandardGoroot(path string) string {
-	// Check if the "bin" subdirectory of our given GOROOT is a symlink, and then
-	// return the _parent_ directory of its destination.
-	if dest, err := os.Readlink(filepath.Join(path, "bin")); nil == err {
-		// Clean the destination to remove any trailing slashes, so that
-		// filepath.Dir will always return the parent.
-		//   (because both "/foo" and "/foo/" are valid symlink destinations,
-		//   but filepath.Dir would return "/" and "/foo", respectively)
-		return filepath.Dir(filepath.Clean(dest))
-	}
-	return path
-}

goenv/version.go

@@ -12,7 +12,7 @@ import (
 
 // Version of TinyGo.
 // Update this value before release of new version of software.
-const Version = "0.18.0-dev"
+const Version = "0.17.0-dev"
 
 // GetGorootVersion returns the major and minor version for a given GOROOT path.
 // If the goroot cannot be determined, (0, 0) is returned.

interp/errors.go

@@ -11,17 +11,19 @@ import (
 	"tinygo.org/x/go-llvm"
 )
 
+var errLiteralToPointer = errors.New("interp: trying to convert literal value to pointer")
+
 // These errors are expected during normal execution and can be recovered from
 // by running the affected function at runtime instead of compile time.
 var (
-	errIntegerAsPointer       = errors.New("interp: trying to use an integer as a pointer (memory-mapped I/O?)")
+	errExpectedPointer        = errors.New("interp: trying to use an integer as a pointer (memory-mapped I/O?)")
 	errUnsupportedInst        = errors.New("interp: unsupported instruction")
 	errUnsupportedRuntimeInst = errors.New("interp: unsupported instruction (to be emitted at runtime)")
 	errMapAlreadyCreated      = errors.New("interp: map already created")
 )
 
 func isRecoverableError(err error) bool {
-	return err == errIntegerAsPointer || err == errUnsupportedInst || err == errUnsupportedRuntimeInst || err == errMapAlreadyCreated
+	return err == errExpectedPointer || err == errUnsupportedInst || err == errUnsupportedRuntimeInst || err == errMapAlreadyCreated
 }
 
 // ErrorLine is one line in a traceback. The position may be missing.

interp/interp.go

@@ -102,7 +102,7 @@ func Run(mod llvm.Module, debug bool) error {
 		if callErr != nil {
 			if isRecoverableError(callErr.Err) {
 				if r.debug {
-					fmt.Fprintln(os.Stderr, "not interpreting", r.pkgName, "because of error:", callErr.Error())
+					fmt.Fprintln(os.Stderr, "not interpretring", r.pkgName, "because of error:", callErr.Err)
 				}
 				mem.revert()
 				continue

interp/interpreter.go

@@ -550,22 +550,7 @@ func (r *runner) run(fn *function, params []value, parentMem *memoryView, indent
 			}
 			ptr, err := operands[0].asPointer(r)
 			if err != nil {
-				if err != errIntegerAsPointer {
-					return nil, mem, r.errorAt(inst, err)
-				}
-				// GEP on fixed pointer value (for example, memory-mapped I/O).
-				ptrValue := operands[0].Uint() + offset
-				switch operands[0].len(r) {
-				case 8:
-					locals[inst.localIndex] = literalValue{uint64(ptrValue)}
-				case 4:
-					locals[inst.localIndex] = literalValue{uint32(ptrValue)}
-				case 2:
-					locals[inst.localIndex] = literalValue{uint16(ptrValue)}
-				default:
-					panic("pointer operand is not of a known pointer size")
-				}
-				continue
+				return nil, mem, r.errorAt(inst, err)
 			}
 			ptr = ptr.addOffset(uint32(offset))
 			locals[inst.localIndex] = ptr

interp/memory.go

@@ -348,7 +348,7 @@ func (v literalValue) clone() value {
 }
 
 func (v literalValue) asPointer(r *runner) (pointerValue, error) {
-	return pointerValue{}, errIntegerAsPointer
+	return pointerValue{}, errLiteralToPointer
 }
 
 func (v literalValue) asRawValue(r *runner) rawValue {
@@ -949,7 +949,7 @@ func (v rawValue) clone() value {
 func (v rawValue) asPointer(r *runner) (pointerValue, error) {
 	if v.buf[0] <= 255 {
 		// Probably a null pointer or memory-mapped I/O.
-		return pointerValue{}, errIntegerAsPointer
+		return pointerValue{}, errExpectedPointer
 	}
 	return pointerValue{v.buf[0]}, nil
 }

ir/ir.go

@@ -0,0 +1,271 @@
+package ir
+
+import (
+	"go/ast"
+	"go/types"
+	"sort"
+	"strings"
+
+	"github.com/tinygo-org/tinygo/loader"
+	"golang.org/x/tools/go/ssa"
+	"tinygo.org/x/go-llvm"
+)
+
+// This file provides a wrapper around go/ssa values and adds extra
+// functionality to them.
+
+// View on all functions, types, and globals in a program, with analysis
+// results.
+type Program struct {
+	Program       *ssa.Program
+	LoaderProgram *loader.Program
+	mainPkg       *ssa.Package
+	Functions     []*Function
+	functionMap   map[*ssa.Function]*Function
+}
+
+// Function or method.
+type Function struct {
+	*ssa.Function
+	LLVMFn   llvm.Value
+	module   string     // go:wasm-module
+	linkName string     // go:linkname, go:export
+	exported bool       // go:export
+	nobounds bool       // go:nobounds
+	flag     bool       // used by dead code elimination
+	inline   InlineType // go:inline
+}
+
+// Interface type that is at some point used in a type assert (to check whether
+// it implements another interface).
+type Interface struct {
+	Num  int
+	Type *types.Interface
+}
+
+type InlineType int
+
+// How much to inline.
+const (
+	// Default behavior. The compiler decides for itself whether any given
+	// function will be inlined. Whether any function is inlined depends on the
+	// optimization level.
+	InlineDefault InlineType = iota
+
+	// Inline hint, just like the C inline keyword (signalled using
+	// //go:inline). The compiler will be more likely to inline this function,
+	// but it is not a guarantee.
+	InlineHint
+
+	// Don't inline, just like the GCC noinline attribute. Signalled using
+	// //go:noinline.
+	InlineNone
+)
+
+// Create and initialize a new *Program from a *ssa.Program.
+func NewProgram(lprogram *loader.Program) *Program {
+	program := lprogram.LoadSSA()
+	program.Build()
+
+	mainPkg := program.Package(lprogram.MainPkg().Pkg)
+	if mainPkg == nil {
+		panic("could not find main package")
+	}
+	p := &Program{
+		Program:       program,
+		LoaderProgram: lprogram,
+		mainPkg:       mainPkg,
+		functionMap:   make(map[*ssa.Function]*Function),
+	}
+
+	for _, pkg := range lprogram.Sorted() {
+		p.AddPackage(program.Package(pkg.Pkg))
+	}
+
+	return p
+}
+
+// Add a package to this Program. All packages need to be added first before any
+// analysis is done for correct results.
+func (p *Program) AddPackage(pkg *ssa.Package) {
+	memberNames := make([]string, 0)
+	for name := range pkg.Members {
+		memberNames = append(memberNames, name)
+	}
+	sort.Strings(memberNames)
+
+	for _, name := range memberNames {
+		member := pkg.Members[name]
+		switch member := member.(type) {
+		case *ssa.Function:
+			p.addFunction(member)
+		case *ssa.Type:
+			methods := getAllMethods(pkg.Prog, member.Type())
+			if !types.IsInterface(member.Type()) {
+				// named type
+				for _, method := range methods {
+					p.addFunction(pkg.Prog.MethodValue(method))
+				}
+			}
+		case *ssa.Global:
+			// Ignore. Globals are not handled here.
+		case *ssa.NamedConst:
+			// Ignore: these are already resolved.
+		default:
+			panic("unknown member type: " + member.String())
+		}
+	}
+}
+
+func (p *Program) addFunction(ssaFn *ssa.Function) {
+	if _, ok := p.functionMap[ssaFn]; ok {
+		return
+	}
+	f := &Function{Function: ssaFn}
+	f.parsePragmas()
+	p.Functions = append(p.Functions, f)
+	p.functionMap[ssaFn] = f
+
+	for _, anon := range ssaFn.AnonFuncs {
+		p.addFunction(anon)
+	}
+}
+
+// Return true if this package imports "unsafe", false otherwise.
+func hasUnsafeImport(pkg *types.Package) bool {
+	for _, imp := range pkg.Imports() {
+		if imp == types.Unsafe {
+			return true
+		}
+	}
+	return false
+}
+
+func (p *Program) GetFunction(ssaFn *ssa.Function) *Function {
+	return p.functionMap[ssaFn]
+}
+
+func (p *Program) MainPkg() *ssa.Package {
+	return p.mainPkg
+}
+
+// Parse compiler directives in the preceding comments.
+func (f *Function) parsePragmas() {
+	if f.Syntax() == nil {
+		return
+	}
+	if decl, ok := f.Syntax().(*ast.FuncDecl); ok && decl.Doc != nil {
+		for _, comment := range decl.Doc.List {
+			text := comment.Text
+			if strings.HasPrefix(text, "//export ") {
+				// Rewrite '//export' to '//go:export' for compatibility with
+				// gc.
+				text = "//go:" + text[2:]
+			}
+			if !strings.HasPrefix(text, "//go:") {
+				continue
+			}
+			parts := strings.Fields(text)
+			switch parts[0] {
+			case "//go:export":
+				if len(parts) != 2 {
+					continue
+				}
+				f.linkName = parts[1]
+				f.exported = true
+			case "//go:wasm-module":
+				// Alternative comment for setting the import module.
+				if len(parts) != 2 {
+					continue
+				}
+				f.module = parts[1]
+			case "//go:inline":
+				f.inline = InlineHint
+			case "//go:noinline":
+				f.inline = InlineNone
+			case "//go:linkname":
+				if len(parts) != 3 || parts[1] != f.Name() {
+					continue
+				}
+				// Only enable go:linkname when the package imports "unsafe".
+				// This is a slightly looser requirement than what gc uses: gc
+				// requires the file to import "unsafe", not the package as a
+				// whole.
+				if hasUnsafeImport(f.Pkg.Pkg) {
+					f.linkName = parts[2]
+				}
+			case "//go:nobounds":
+				// Skip bounds checking in this function. Useful for some
+				// runtime functions.
+				// This is somewhat dangerous and thus only imported in packages
+				// that import unsafe.
+				if hasUnsafeImport(f.Pkg.Pkg) {
+					f.nobounds = true
+				}
+			}
+		}
+	}
+}
+
+func (f *Function) IsNoBounds() bool {
+	return f.nobounds
+}
+
+// Return true iff this function is externally visible.
+func (f *Function) IsExported() bool {
+	return f.exported || f.CName() != ""
+}
+
+// Return the inline directive of this function.
+func (f *Function) Inline() InlineType {
+	return f.inline
+}
+
+// Return the module name if not the default.
+func (f *Function) Module() string {
+	return f.module
+}
+
+// Return the link name for this function.
+func (f *Function) LinkName() string {
+	if f.linkName != "" {
+		return f.linkName
+	}
+	if f.Signature.Recv() != nil {
+		// Method on a defined type (which may be a pointer).
+		return f.RelString(nil)
+	} else {
+		// Bare function.
+		if name := f.CName(); name != "" {
+			// Name CGo functions directly.
+			return name
+		} else {
+			return f.RelString(nil)
+		}
+	}
+}
+
+// Return the name of the C function if this is a CGo wrapper. Otherwise, return
+// a zero-length string.
+func (f *Function) CName() string {
+	name := f.Name()
+	if strings.HasPrefix(name, "_Cfunc_") {
+		// emitted by `go tool cgo`
+		return name[len("_Cfunc_"):]
+	}
+	if strings.HasPrefix(name, "C.") {
+		// created by ../loader/cgo.go
+		return name[2:]
+	}
+	return ""
+}
+
+// Get all methods of a type.
+func getAllMethods(prog *ssa.Program, typ types.Type) []*types.Selection {
+	ms := prog.MethodSets.MethodSet(typ)
+	methods := make([]*types.Selection, ms.Len())
+	for i := 0; i < ms.Len(); i++ {
+		methods[i] = ms.At(i)
+	}
+	return methods
+}

ir/passes.go

@@ -0,0 +1,149 @@
+package ir
+
+import (
+	"errors"
+	"go/types"
+
+	"golang.org/x/tools/go/ssa"
+)
+
+// This file implements several optimization passes (analysis + transform) to
+// optimize code in SSA form before it is compiled to LLVM IR. It is based on
+// the IR defined in ir.go.
+
+// Make a readable version of a method signature (including the function name,
+// excluding the receiver name). This string is used internally to match
+// interfaces and to call the correct method on an interface. Examples:
+//
+//     String() string
+//     Read([]byte) (int, error)
+func MethodSignature(method *types.Func) string {
+	return method.Name() + signature(method.Type().(*types.Signature))
+}
+
+// Make a readable version of a function (pointer) signature.
+// Examples:
+//
+//     () string
+//     (string, int) (int, error)
+func signature(sig *types.Signature) string {
+	s := ""
+	if sig.Params().Len() == 0 {
+		s += "()"
+	} else {
+		s += "("
+		for i := 0; i < sig.Params().Len(); i++ {
+			if i > 0 {
+				s += ", "
+			}
+			s += sig.Params().At(i).Type().String()
+		}
+		s += ")"
+	}
+	if sig.Results().Len() == 0 {
+		// keep as-is
+	} else if sig.Results().Len() == 1 {
+		s += " " + sig.Results().At(0).Type().String()
+	} else {
+		s += " ("
+		for i := 0; i < sig.Results().Len(); i++ {
+			if i > 0 {
+				s += ", "
+			}
+			s += sig.Results().At(i).Type().String()
+		}
+		s += ")"
+	}
+	return s
+}
+
+// Simple pass that removes dead code. This pass makes later analysis passes
+// more useful.
+func (p *Program) SimpleDCE() error {
+	// Unmark all functions.
+	for _, f := range p.Functions {
+		f.flag = false
+	}
+
+	// Initial set of live functions. Include main.main, *.init and runtime.*
+	// functions.
+	main, ok := p.mainPkg.Members["main"].(*ssa.Function)
+	if !ok {
+		if p.mainPkg.Members["main"] == nil {
+			return errors.New("function main is undeclared in the main package")
+		} else {
+			return errors.New("cannot declare main - must be func")
+		}
+	}
+	runtimePkg := p.Program.ImportedPackage("runtime")
+	mathPkg := p.Program.ImportedPackage("math")
+	taskPkg := p.Program.ImportedPackage("internal/task")
+	p.GetFunction(main).flag = true
+	worklist := []*ssa.Function{main}
+	for _, f := range p.Functions {
+		if f.exported || f.Synthetic == "package initializer" || f.Pkg == runtimePkg || f.Pkg == taskPkg || (f.Pkg == mathPkg && f.Pkg != nil) {
+			if f.flag {
+				continue
+			}
+			f.flag = true
+			worklist = append(worklist, f.Function)
+		}
+	}
+
+	// Mark all called functions recursively.
+	for len(worklist) != 0 {
+		f := worklist[len(worklist)-1]
+		worklist = worklist[:len(worklist)-1]
+		for _, block := range f.Blocks {
+			for _, instr := range block.Instrs {
+				if instr, ok := instr.(*ssa.MakeInterface); ok {
+					for _, sel := range getAllMethods(p.Program, instr.X.Type()) {
+						fn := p.Program.MethodValue(sel)
+						callee := p.GetFunction(fn)
+						if callee == nil {
+							// TODO: why is this necessary?
+							p.addFunction(fn)
+							callee = p.GetFunction(fn)
+						}
+						if !callee.flag {
+							callee.flag = true
+							worklist = append(worklist, callee.Function)
+						}
+					}
+				}
+				for _, operand := range instr.Operands(nil) {
+					if operand == nil || *operand == nil {
+						continue
+					}
+					switch operand := (*operand).(type) {
+					case *ssa.Function:
+						f := p.GetFunction(operand)
+						if f == nil {
+							// FIXME HACK: this function should have been
+							// discovered already. It is not for bound methods.
+							p.addFunction(operand)
+							f = p.GetFunction(operand)
+						}
+						if !f.flag {
+							f.flag = true
+							worklist = append(worklist, operand)
+						}
+					}
+				}
+			}
+		}
+	}
+
+	// Remove unmarked functions.
+	livefunctions := []*Function{}
+	for _, f := range p.Functions {
+		if f.flag {
+			livefunctions = append(livefunctions, f)
+		} else {
+			delete(p.functionMap, f.Function)
+		}
+	}
+	p.Functions = livefunctions
+
+	return nil
+}

loader/loader.go

@@ -2,7 +2,6 @@ package loader
 
 import (
 	"bytes"
-	"crypto/sha512"
 	"encoding/json"
 	"errors"
 	"fmt"
@@ -12,12 +11,12 @@ import (
 	"go/token"
 	"go/types"
 	"io"
-	"io/ioutil"
 	"os"
 	"os/exec"
 	"path/filepath"
 	"strconv"
 	"strings"
+	"syscall"
 
 	"github.com/tinygo-org/tinygo/cgo"
 	"github.com/tinygo-org/tinygo/compileopts"
@@ -53,8 +52,7 @@ type PackageJSON struct {
 	CFiles   []string
 
 	// Dependency information
-	Imports   []string
-	ImportMap map[string]string
+	Imports []string
 
 	// Error information
 	Error *struct {
@@ -68,12 +66,10 @@ type PackageJSON struct {
 type Package struct {
 	PackageJSON
 
-	program    *Program
-	Files      []*ast.File
-	FileHashes map[string][]byte
-	CFlags     []string // CFlags used during CGo preprocessing (only set if CGo is used)
-	Pkg        *types.Package
-	info       types.Info
+	program *Program
+	Files   []*ast.File
+	Pkg     *types.Package
+	info    types.Info
 }
 
 // Load loads the given package with all dependencies (including the runtime
@@ -113,7 +109,10 @@ func Load(config *compileopts.Config, inputPkgs []string, clangHeaders string, t
 	err = cmd.Run()
 	if err != nil {
 		if exitErr, ok := err.(*exec.ExitError); ok {
-			os.Exit(exitErr.ExitCode())
+			if status, ok := exitErr.Sys().(syscall.WaitStatus); ok {
+				os.Exit(status.ExitStatus())
+			}
+			os.Exit(1)
 		}
 		return nil, fmt.Errorf("failed to run `go list`: %s", err)
 	}
@@ -122,8 +121,7 @@ func Load(config *compileopts.Config, inputPkgs []string, clangHeaders string, t
 	decoder := json.NewDecoder(buf)
 	for {
 		pkg := &Package{
-			program:    p,
-			FileHashes: make(map[string][]byte),
+			program: p,
 			info: types.Info{
 				Types:      make(map[ast.Expr]types.TypeAndValue),
 				Defs:       make(map[*ast.Ident]types.Object),
@@ -282,15 +280,17 @@ func (p *Program) Parse() error {
 }
 
 // parseFile is a wrapper around parser.ParseFile.
-func (p *Package) parseFile(path string, mode parser.Mode) (*ast.File, error) {
-	originalPath := p.program.getOriginalPath(path)
-	data, err := ioutil.ReadFile(path)
+func (p *Program) parseFile(path string, mode parser.Mode) (*ast.File, error) {
+	if p.fset == nil {
+		p.fset = token.NewFileSet()
+	}
+
+	rd, err := os.Open(path)
 	if err != nil {
 		return nil, err
 	}
-	sum := sha512.Sum512_224(data)
-	p.FileHashes[originalPath] = sum[:]
-	return parser.ParseFile(p.program.fset, originalPath, data, mode)
+	defer rd.Close()
+	return parser.ParseFile(p.fset, p.getOriginalPath(path), rd, mode)
 }
 
 // Parse parses and typechecks this package.
@@ -366,7 +366,7 @@ func (p *Package) parseFiles() ([]*ast.File, error) {
 		if !filepath.IsAbs(file) {
 			file = filepath.Join(p.Dir, file)
 		}
-		f, err := p.parseFile(file, parser.ParseComments)
+		f, err := p.program.parseFile(file, parser.ParseComments)
 		if err != nil {
 			fileErrs = append(fileErrs, err)
 			return
@@ -388,11 +388,7 @@ func (p *Package) parseFiles() ([]*ast.File, error) {
 		if p.program.clangHeaders != "" {
 			cflags = append(cflags, "-Xclang", "-internal-isystem", "-Xclang", p.program.clangHeaders)
 		}
-		p.CFlags = cflags
-		generated, ldflags, accessedFiles, errs := cgo.Process(files, p.program.workingDir, p.program.fset, cflags)
-		for path, hash := range accessedFiles {
-			p.FileHashes[path] = hash
-		}
+		generated, ldflags, errs := cgo.Process(files, p.program.workingDir, p.program.fset, cflags)
 		if errs != nil {
 			fileErrs = append(fileErrs, errs...)
 		}
@@ -415,9 +411,6 @@ func (p *Package) Import(to string) (*types.Package, error) {
 	if to == "unsafe" {
 		return types.Unsafe, nil
 	}
-	if newTo, ok := p.ImportMap[to]; ok && !strings.HasSuffix(newTo, ".test]") {
-		to = newTo
-	}
 	if imported, ok := p.program.Packages[to]; ok {
 		return imported.Pkg, nil
 	} else {

main.go

@@ -15,16 +15,14 @@ import (
 	"path/filepath"
 	"runtime"
 	"strings"
-	"sync/atomic"
+	"syscall"
 	"time"
 
-	"github.com/mattn/go-colorable"
 	"github.com/tinygo-org/tinygo/builder"
 	"github.com/tinygo-org/tinygo/compileopts"
 	"github.com/tinygo-org/tinygo/goenv"
 	"github.com/tinygo-org/tinygo/interp"
 	"github.com/tinygo-org/tinygo/loader"
-	"github.com/tinygo-org/tinygo/transform"
 	"tinygo.org/x/go-llvm"
 
 	"go.bug.st/serial"
@@ -165,7 +163,10 @@ func Test(pkgName string, options *compileopts.Options, testCompileOnly bool, ou
 			if err != nil {
 				// Propagate the exit code
 				if err, ok := err.(*exec.ExitError); ok {
-					os.Exit(err.ExitCode())
+					if status, ok := err.Sys().(syscall.WaitStatus); ok {
+						os.Exit(status.ExitStatus())
+					}
+					os.Exit(1)
 				}
 				return &commandError{"failed to run compiled binary", result.Binary, err}
 			}
@@ -262,7 +263,7 @@ func Flash(pkgName, port string, options *compileopts.Options) error {
 			// Create the command.
 			flashCmd := config.Target.FlashCommand
 			fileToken := "{" + fileExt[1:] + "}"
-			flashCmd = strings.ReplaceAll(flashCmd, fileToken, result.Binary)
+			flashCmd = strings.Replace(flashCmd, fileToken, result.Binary, -1)
 
 			if port == "" && strings.Contains(flashCmd, "{port}") {
 				var err error
@@ -272,7 +273,7 @@ func Flash(pkgName, port string, options *compileopts.Options) error {
 				}
 			}
 
-			flashCmd = strings.ReplaceAll(flashCmd, "{port}", port)
+			flashCmd = strings.Replace(flashCmd, "{port}", port, -1)
 
 			// Execute the command.
 			var cmd *exec.Cmd
@@ -391,7 +392,7 @@ func FlashGDB(pkgName string, ocdOutput bool, options *compileopts.Options) erro
 			if ocdOutput {
 				// Make it clear which output is from the daemon.
 				w := &ColorWriter{
-					Out:    colorable.NewColorableStderr(),
+					Out:    os.Stderr,
 					Prefix: "openocd: ",
 					Color:  TermColorYellow,
 				}
@@ -406,7 +407,7 @@ func FlashGDB(pkgName string, ocdOutput bool, options *compileopts.Options) erro
 			if ocdOutput {
 				// Make it clear which output is from the daemon.
 				w := &ColorWriter{
-					Out:    colorable.NewColorableStderr(),
+					Out:    os.Stderr,
 					Prefix: "jlink: ",
 					Color:  TermColorYellow,
 				}
@@ -463,15 +464,8 @@ func FlashGDB(pkgName string, ocdOutput bool, options *compileopts.Options) erro
 			}
 			defer func() {
 				daemon.Process.Signal(os.Interrupt)
-				var stopped uint32
-				go func() {
-					time.Sleep(time.Millisecond * 100)
-					if atomic.LoadUint32(&stopped) == 0 {
-						daemon.Process.Kill()
-					}
-				}()
+				// Maybe we should send a .Kill() after x seconds?
 				daemon.Wait()
-				atomic.StoreUint32(&stopped, 1)
 			}()
 		}
 
@@ -773,15 +767,6 @@ func printCompilerError(logln func(...interface{}), err error) {
 				logln()
 			}
 		}
-	case transform.CoroutinesError:
-		logln(err.Pos.String() + ": " + err.Msg)
-		logln("\ntraceback:")
-		for _, line := range err.Traceback {
-			logln(line.Name)
-			if line.Position.IsValid() {
-				logln("\t" + line.Position.String())
-			}
-		}
 	case loader.Errors:
 		logln("#", err.Pkg.ImportPath)
 		for _, err := range err.Errs {
@@ -947,17 +932,9 @@ func main() {
 			fmt.Fprintf(os.Stderr, "Unknown library: %s\n", name)
 			os.Exit(1)
 		}
-		tmpdir, err := ioutil.TempDir("", "tinygo*")
-		if err != nil {
-			handleCompilerError(err)
-		}
-		defer os.RemoveAll(tmpdir)
-		path, err := lib.Load(*target, tmpdir)
+		path, err := lib.Load(*target)
 		handleCompilerError(err)
-		err = copyFile(path, outpath)
-		if err != nil {
-			handleCompilerError(err)
-		}
+		copyFile(path, outpath)
 	case "flash", "gdb":
 		pkgName := filepath.ToSlash(flag.Arg(0))
 		if command == "flash" {
@@ -1076,7 +1053,10 @@ func main() {
 		err = cmd.Run()
 		if err != nil {
 			if exitErr, ok := err.(*exec.ExitError); ok {
-				os.Exit(exitErr.ExitCode())
+				if status, ok := exitErr.Sys().(syscall.WaitStatus); ok {
+					os.Exit(status.ExitStatus())
+				}
+				os.Exit(1)
 			}
 			fmt.Fprintln(os.Stderr, "failed to run `go list`:", err)
 			os.Exit(1)

main_test.go

@@ -58,9 +58,6 @@ func TestCompiler(t *testing.T) {
 	if runtime.GOOS != "windows" {
 		t.Run("Host", func(t *testing.T) {
 			runPlatTests("", matches, t)
-			if runtime.GOOS == "darwin" {
-				runTest("testdata/libc/env.go", "", t, []string{"ENV1=VALUE1", "ENV2=VALUE2"}...)
-			}
 		})
 	}
 
@@ -107,7 +104,6 @@ func TestCompiler(t *testing.T) {
 
 		t.Run("WASI", func(t *testing.T) {
 			runPlatTests("wasi", matches, t)
-			runTest("testdata/libc/env.go", "wasi", t, []string{"ENV1=VALUE1", "ENV2=VALUE2"}...)
 		})
 	}
 }
@@ -117,6 +113,7 @@ func runPlatTests(target string, matches []string, t *testing.T) {
 
 	for _, path := range matches {
 		path := path // redefine to avoid race condition
+
 		t.Run(filepath.Base(path), func(t *testing.T) {
 			t.Parallel()
 			runTest(path, target, t)
@@ -136,7 +133,7 @@ func runBuild(src, out string, opts *compileopts.Options) error {
 	return Build(src, out, opts)
 }
 
-func runTest(path, target string, t *testing.T, environmentVars ...string) {
+func runTest(path, target string, t *testing.T) {
 	// Get the expected output for this test.
 	txtpath := path[:len(path)-3] + ".txt"
 	if path[len(path)-1] == os.PathSeparator {
@@ -185,7 +182,6 @@ func runTest(path, target string, t *testing.T, environmentVars ...string) {
 	ranTooLong := false
 	if target == "" {
 		cmd = exec.Command(binary)
-		cmd.Env = append(cmd.Env, environmentVars...)
 	} else {
 		spec, err := compileopts.LoadTarget(target)
 		if err != nil {
@@ -197,14 +193,6 @@ func runTest(path, target string, t *testing.T, environmentVars ...string) {
 			args := append(spec.Emulator[1:], binary)
 			cmd = exec.Command(spec.Emulator[0], args...)
 		}
-
-		if len(spec.Emulator) != 0 && spec.Emulator[0] == "wasmtime" {
-			for _, v := range environmentVars {
-				cmd.Args = append(cmd.Args, "--env", v)
-			}
-		} else {
-			cmd.Env = append(cmd.Env, environmentVars...)
-		}
 	}
 	stdout := &bytes.Buffer{}
 	cmd.Stdout = stdout

src/examples/adc/adc.go

@@ -15,7 +15,7 @@ func main() {
 	led.Configure(machine.PinConfig{Mode: machine.PinOutput})
 
 	sensor := machine.ADC{machine.ADC2}
-	sensor.Configure(machine.ADCConfig{})
+	sensor.Configure()
 
 	for {
 		val := sensor.Get()

src/internal/task/task_coroutine.go

@@ -77,9 +77,22 @@ func Current() *Task
 // This is implemented inside the compiler.
 func Pause()
 
+type taskHolder interface {
+	setState(*rawState) *rawState
+	returnTo(*rawState)
+	returnCurrent()
+	setReturnPtr(unsafe.Pointer)
+	getReturnPtr() unsafe.Pointer
+}
+
+// If there are no direct references to the task methods, they will not be discovered by the compiler, and this will trigger a compiler error.
+// Instantiating this interface forces discovery of these methods.
+var _ = taskHolder((*Task)(nil))
+
 func fake() {
 	// Hack to ensure intrinsics are discovered.
 	Current()
+	go func() {}()
 	Pause()
 }
 

src/machine/adc.go

@@ -1,12 +0,0 @@
-package machine
-
-// Hardware abstraction layer for the analog-to-digital conversion (ADC)
-// peripheral.
-
-// ADCConfig holds ADC configuration parameters. If left unspecified, the zero
-// value of each parameter will use the peripheral's default settings.
-type ADCConfig struct {
-	Reference  uint32 // analog reference voltage (AREF) in millivolts
-	Resolution uint32 // number of bits for a single conversion (e.g., 8, 10, 12)
-	Samples    uint32 // number of samples for a single conversion (e.g., 4, 8, 16, 32)
-}

src/machine/board_bluepill.go

@@ -85,6 +85,6 @@ const (
 
 // I2C pins
 const (
-	I2C0_SDA_PIN = PB7
-	I2C0_SCL_PIN = PB6
+	SDA_PIN = PB7
+	SCL_PIN = PB6
 )

src/machine/board_circuitplay_bluefruit.go

@@ -66,8 +66,8 @@ const (
 	SDA_PIN = P0_05 // I2C0 external
 	SCL_PIN = P0_04 // I2C0 external
 
-	SDA1_PIN = P1_10 // I2C1 internal
-	SCL1_PIN = P1_12 // I2C1 internal
+	SDA1_PIN = P0_00 // I2C1 internal
+	SCL1_PIN = P0_01 // I2C1 internal
 )
 
 // SPI pins (internal flash)

src/machine/board_clue_alpha.go

@@ -2,7 +2,7 @@
 
 package machine
 
-const HasLowFrequencyCrystal = false
+const HasLowFrequencyCrystal = true
 
 // GPIO Pins
 const (

src/machine/board_grandcentral-m4.go

@@ -1,243 +0,0 @@
-// +build grandcentral_m4
-
-package machine
-
-// Digital pins
-const (
-	//  = Pin     Alt. Function        SERCOM   PWM Timer   Interrupt
-	//   ------  -------------------- -------- ----------- -----------
-	D0  = PB25 // UART1 RX              0[1]                 EXTI9
-	D1  = PB24 // UART1 TX              0[0]                 EXTI8
-	D2  = PC18 //                                TCC0[2]     EXTI2
-	D3  = PC19 //                                TCC0[3]     EXTI3
-	D4  = PC20 //                                TCC0[4]     EXTI4
-	D5  = PC21 //                                TCC0[5]     EXTI5
-	D6  = PD20 //                                TCC1[0]     EXTI10
-	D7  = PD21 //                                TCC1[1]     EXTI11
-	D8  = PB18 //                                TCC1[0]     EXTI2
-	D9  = PB02 //                                TC6[0]      EXTI3
-	D10 = PB22 //                                TC7[0]      EXTI6
-	D11 = PB23 //                                            EXTI7
-	D12 = PB00 //                                TC7[0]      EXTI0
-	D13 = PB01 // On-board LED                   TC7[1]      EXTI1
-	D14 = PB16 // UART4 TX, I2S0 SCK    5[0]     TC6[0]      EXTI0
-	D15 = PB17 // UART4 RX, I2S0 MCK    5[1]                 EXTI1
-	D16 = PC22 // UART3 TX              1[0]                 EXTI6
-	D17 = PC23 // UART3 RX              1[1]                 EXTI6
-	D18 = PB12 // UART2 TX              4[0]     TCC3[0]     EXTI12
-	D19 = PB13 // UART2 RX              4[1]     TCC3[1]     EXTI13
-	D20 = PB20 // I2C0 SDA              3[0]                 EXTI4
-	D21 = PB21 // I2C0 SCL              3[1]                 EXTI5
-	D22 = PD12 //                                            EXTI7
-	D23 = PA15 //                                TCC2[1]     EXTI15
-	D24 = PC17 // I2C1 SCL              6[1]     TCC0[1]     EXTI1
-	D25 = PC16 // I2C1 SDA              6[0]     TCC0[0]     EXTI0
-	D26 = PA12 // PCC DEN1                       TC2[0]      EXTI12
-	D27 = PA13 // PCC DEN2                       TC2[1]      EXTI13
-	D28 = PA14 // PCC CLK                        TCC2[0]     EXTI14
-	D29 = PB19 // PCC XCLK                                   EXTI3
-	D30 = PA23 // PCC D7                         TC4[1]      EXTI7
-	D31 = PA22 // PCC D6, I2S0 SDI               TC4[0]      EXTI6
-	D32 = PA21 // PCC D5, I2S0 SDO                           EXTI5
-	D33 = PA20 // PCC D4, I2S0 FS                            EXTI4
-	D34 = PA19 // PCC D3                         TC3[1]      EXTI3
-	D35 = PA18 // PCC D2                         TC3[0]      EXTI2
-	D36 = PA17 // PCC D1                                     EXTI1
-	D37 = PA16 // PCC D0                                     EXTI0
-	D38 = PB15 // PCC D9                         TCC4[1]     EXTI15
-	D39 = PB14 // PCC D8                         TCC4[0]     EXTI14
-	D40 = PC13 // PCC D11                                    EXTI13
-	D41 = PC12 // PCC D10                                    EXTI12
-	D42 = PC15 // PCC D13                                    EXTI15
-	D43 = PC14 // PCC D12                                    EXTI14
-	D44 = PC11 //                                            EXTI11
-	D45 = PC10 //                                            EXTI10
-	D46 = PC06 //                                            EXTI6
-	D47 = PC07 //                                            EXTI5
-	D48 = PC04 //                                            EXTI4
-	D49 = PC05 //                                            EXTI5
-	D50 = PD11 // SPI0 SDI              7[3]                 EXTI11
-	D51 = PD08 // SPI0 SDO              7[0]                 EXTI8
-	D52 = PD09 // SPI0 SCK              7[1]                 EXTI9
-	D53 = PD10 // SPI0 CS                                    EXTI10
-	D54 = PB05 // ADC1 (A8)                                  EXTI5
-	D55 = PB06 // ADC1 (A9)                                  EXTI6
-	D56 = PB07 // ADC1 (A10)                                 EXTI7
-	D57 = PB08 // ADC1 (A11)                                 EXTI8
-	D58 = PB09 // ADC1 (A12)                                 EXTI9
-	D59 = PA04 // ADC0 (A13)                     TC0[0]      EXTI4
-	D60 = PA06 // ADC0 (A14)                     TC1[0]      EXTI6
-	D61 = PA07 // ADC0 (A15)                     TC1[1]      EXTI7
-	D62 = PB20 // I2C0 SDA              3[0]     TCC1[2]     EXTI4
-	D63 = PB21 // I2C0 SCL              3[1]     TCC1[3]     EXTI5
-	D64 = PD11 // SPI0 SDI              7[3]                 EXTI6
-	D65 = PD08 // SPI0 SDO              7[0]                 EXTI3
-	D66 = PD09 // SPI0 SCK              7[1]                 EXTI4
-	D67 = PA02 // ADC0 (A0), DAC0                            EXTI2
-	D68 = PA05 // ADC0 (A1), DAC1                            EXTI5
-	D69 = PB03 // ADC0 (A2)                      TC6[1]      EXTI3
-	D70 = PC00 // ADC1 (A3)                                  EXTI0
-	D71 = PC01 // ADC1 (A4)                                  EXTI1
-	D72 = PC02 // ADC1 (A5)                                  EXTI2
-	D73 = PC03 // ADC1 (A6)                                  EXTI3
-	D74 = PB04 // ADC1 (A7)                                  EXTI4
-	D75 = PC31 // UART RX LED
-	D76 = PC30 // UART TX LED
-	D77 = PA27 // USB HOST EN
-	D78 = PA24 // USB DM                                     EXTI8
-	D79 = PA25 // USB DP                                     EXTI9
-	D80 = PB29 // SD/SPI1 SDI           2[3]
-	D81 = PB27 // SD/SPI1 SCK           2[1]
-	D82 = PB26 // SD/SPI1 SDO           2[0]
-	D83 = PB28 // SD/SPI1 CS
-	D84 = PA03 // AREF                                       EXTI3
-	D85 = PA02 // DAC0                                       EXTI2
-	D86 = PA05 // DAC1                                       EXTI5
-	D87 = PB01 // On-board LED (D13)             TC7[1]      EXTI1
-	D88 = PC24 // On-board NeoPixel
-	D89 = PB10 // QSPI SCK                                   EXTI10
-	D90 = PB11 // QSPI CS                                    EXTI11
-	D91 = PA08 // QSPI ID0                                   EXTI(NMI)
-	D92 = PA09 // QSPI ID1                                   EXTI9
-	D93 = PA10 // QSPI ID2                                   EXTI10
-	D94 = PA11 // QSPI ID3                                   EXTI11
-	D95 = PB31 // SD Detect                                  EXTI15
-	D96 = PB30 // SWO                                        EXTI14
-)
-
-// Analog pins
-const (
-	A0  = D67 // (PA02) ADC0 ch. 0,
-	A1  = D68 // (PA05) ADC0 ch. 5,
-	A2  = D69 // (PB03) ADC0 ch. 15
-	A3  = D70 // (PC00) ADC1 ch. 10
-	A4  = D71 // (PC01) ADC1 ch. 11
-	A5  = D72 // (PC02) ADC1 ch. 4
-	A6  = D73 // (PC03) ADC1 ch. 5
-	A7  = D74 // (PB04) ADC1 ch. 6
-	A8  = D54 // (PB05) ADC1 ch. 7
-	A9  = D55 // (PB06) ADC1 ch. 8
-	A10 = D56 // (PB07) ADC1 ch. 9
-	A11 = D57 // (PB08) ADC1 ch. 0
-	A12 = D58 // (PB09) ADC1 ch. 1
-	A13 = D59 // (PA04) ADC0 ch. 4
-	A14 = D60 // (PA06) ADC0 ch. 6
-	A15 = D61 // (PA07) ADC0 ch. 7
-
-	AREF = D84 // (PA03)
-)
-
-// LED pins
-const (
-	LED_PIN         = D13 // (PB01), also on D87
-	UART_RX_LED_PIN = D75 // (PC31)
-	UART_TX_LED_PIN = D76 // (PC30)
-	NEOPIXEL_PIN    = D88 // (PC24)
-
-	// aliases used by examples and drivers
-	LED      = LED_PIN
-	LED_RX   = UART_RX_LED_PIN
-	LED_TX   = UART_TX_LED_PIN
-	NEOPIXEL = NEOPIXEL_PIN
-)
-
-// UART pins
-const (
-	UART1_RX_PIN = D0 // (PB25)
-	UART1_TX_PIN = D1 // (PB24)
-
-	UART2_RX_PIN = D19 // (PB13)
-	UART2_TX_PIN = D18 // (PB12)
-
-	UART3_RX_PIN = D17 // (PC23)
-	UART3_TX_PIN = D16 // (PC22)
-
-	UART4_RX_PIN = D15 // (PB17)
-	UART4_TX_PIN = D14 // (PB16)
-
-	UART_RX_PIN = UART1_RX_PIN // default pins
-	UART_TX_PIN = UART1_TX_PIN //
-)
-
-// SPI pins
-const (
-	SPI0_SCK_PIN = D66 // (PD09), also on D52
-	SPI0_SDO_PIN = D65 // (PD08), also on D51
-	SPI0_SDI_PIN = D64 // (PD11), also on D50
-	SPI0_CS_PIN  = D53 // (PD10)
-
-	SPI1_SCK_PIN = D81 // (PB27)
-	SPI1_SDO_PIN = D82 // (PB26)
-	SPI1_SDI_PIN = D80 // (PB29)
-
-	SPI_SCK_PIN = SPI0_SCK_PIN // default pins
-	SPI_SDO_PIN = SPI0_SDO_PIN //
-	SPI_SDI_PIN = SPI0_SDI_PIN //
-	SPI_CS_PIN  = SPI0_CS_PIN  //
-)
-
-// I2C pins
-const (
-	I2C0_SDA_PIN = D62 // (PB20), also on D20
-	I2C0_SCL_PIN = D63 // (PB21), also on D21
-
-	I2C1_SDA_PIN = D25 // (PC16)
-	I2C1_SCL_PIN = D24 // (PC17)
-
-	I2C_SDA_PIN = I2C0_SDA_PIN // default pins
-	I2C_SCL_PIN = I2C0_SCL_PIN //
-
-	SDA_PIN = I2C_SDA_PIN // unconventional pin names
-	SCL_PIN = I2C_SCL_PIN //  (required by machine_atsamd51.go)
-)
-
-// I2S pins
-const (
-	I2S0_SCK_PIN = D14 // (PB16)
-	I2S0_MCK_PIN = D15 // (PB17)
-	I2S0_FS_PIN  = D33 // (PA20)
-	I2S0_SDO_PIN = D32 // (PA21)
-	I2S0_SDI_PIN = D31 // (PA22)
-
-	I2S_SCK_PIN = I2S0_SCK_PIN // default pins
-	I2S_WS_PIN  = I2S0_FS_PIN  //
-	I2S_SD_PIN  = I2S0_SDO_PIN //
-)
-
-// SD card pins
-const (
-	SD0_SCK_PIN = D81 // (PB27)
-	SD0_SDO_PIN = D82 // (PB26)
-	SD0_SDI_PIN = D80 // (PB29)
-	SD0_CS_PIN  = D83 // (PB28)
-	SD0_DET_PIN = D95 // (PB31)
-
-	SDCARD_SCK_PIN = SD0_SCK_PIN // default pins
-	SDCARD_SDO_PIN = SD0_SDO_PIN //
-	SDCARD_SDI_PIN = SD0_SDI_PIN //
-	SDCARD_CS_PIN  = SD0_CS_PIN  //
-	SDCARD_DET_PIN = SD0_DET_PIN //
-)
-
-// Other peripheral constants
-const (
-	RESET_MAGIC_VALUE = 0xF01669EF // Used to reset into bootloader
-)
-
-// USB CDC pins
-const (
-	USBCDC_HOSTEN_PIN = D77 // (PA27) host enable
-	USBCDC_DM_PIN     = D78 // (PA24) D-
-	USBCDC_DP_PIN     = D79 // (PA25) D+
-)
-
-// USB CDC identifiers
-const (
-	usb_STRING_PRODUCT      = "Adafruit Grand Central M4"
-	usb_STRING_MANUFACTURER = "Adafruit"
-)
-
-var (
-	usb_VID uint16 = 0x239A
-	usb_PID uint16 = 0x8031
-)

src/machine/board_grandcentral-m4_baremetal.go

@@ -1,63 +0,0 @@
-// +build grandcentral_m4
-
-package machine
-
-import (
-	"device/sam"
-	"runtime/interrupt"
-)
-
-func init() {
-	UART1.Interrupt = interrupt.New(sam.IRQ_SERCOM0_2, UART1.handleInterrupt)
-	UART2.Interrupt = interrupt.New(sam.IRQ_SERCOM4_2, UART2.handleInterrupt)
-	UART3.Interrupt = interrupt.New(sam.IRQ_SERCOM1_2, UART3.handleInterrupt)
-	UART4.Interrupt = interrupt.New(sam.IRQ_SERCOM5_2, UART4.handleInterrupt)
-}
-
-// UART on the Grand Central M4
-var (
-	UART1 = UART{
-		Buffer: NewRingBuffer(),
-		Bus:    sam.SERCOM0_USART_INT,
-		SERCOM: 0,
-	}
-	UART2 = UART{
-		Buffer: NewRingBuffer(),
-		Bus:    sam.SERCOM4_USART_INT,
-		SERCOM: 4,
-	}
-	UART3 = UART{
-		Buffer: NewRingBuffer(),
-		Bus:    sam.SERCOM1_USART_INT,
-		SERCOM: 1,
-	}
-	UART4 = UART{
-		Buffer: NewRingBuffer(),
-		Bus:    sam.SERCOM5_USART_INT,
-		SERCOM: 5,
-	}
-)
-
-// I2C on the Grand Central M4
-var (
-	I2C0 = I2C{
-		Bus:    sam.SERCOM3_I2CM,
-		SERCOM: 3,
-	}
-	I2C1 = I2C{
-		Bus:    sam.SERCOM6_I2CM,
-		SERCOM: 6,
-	}
-)
-
-// SPI on the Grand Central M4
-var (
-	SPI0 = SPI{
-		Bus:    sam.SERCOM7_SPIM,
-		SERCOM: 7,
-	}
-	SPI1 = SPI{ // SD card
-		Bus:    sam.SERCOM2_SPIM,
-		SERCOM: 2,
-	}
-)

src/machine/board_microbit-v2.go

@@ -90,16 +90,16 @@ const (
 
 // LED matrix pins
 const (
-	LED_COL_1 Pin = P0_28
-	LED_COL_2 Pin = P0_11
-	LED_COL_3 Pin = P0_31
-	LED_COL_4 Pin = P1_05
-	LED_COL_5 Pin = P0_30
-	LED_ROW_1 Pin = P0_21
-	LED_ROW_2 Pin = P0_22
-	LED_ROW_3 Pin = P0_15
-	LED_ROW_4 Pin = P0_24
-	LED_ROW_5 Pin = P0_19
+	LED_COL_1 Pin = P4
+	LED_COL_2 Pin = P7
+	LED_COL_3 Pin = P3
+	LED_COL_4 Pin = P6
+	LED_COL_5 Pin = P10
+	LED_ROW_1 Pin = P21
+	LED_ROW_2 Pin = P22
+	LED_ROW_3 Pin = P23
+	LED_ROW_4 Pin = P24
+	LED_ROW_5 Pin = P25
 )
 
 // USB CDC identifiers

src/machine/board_nicenano.go

@@ -1,84 +0,0 @@
-// +build nicenano
-
-package machine
-
-const HasLowFrequencyCrystal = true
-
-// GPIO Pins
-const (
-	D006 = P0_06
-	D008 = P0_08
-	D017 = P0_17
-	D020 = P0_20
-	D022 = P0_22
-	D024 = P0_24
-	D100 = P1_00
-	D011 = P0_11
-	D104 = P1_04
-	D106 = P1_06
-
-	D004 = P0_04 // AIN2; P0.04 (AIN2) is used to read the voltage of the battery via ADC. It can’t be used for any other function.
-	D013 = P0_13 // VCC 3.3V; P0.13 on VCC shuts off the power to VCC when you set it to high; This saves on battery immensely for LEDs of all kinds that eat power even when off
-	D115 = P1_15
-	D113 = P1_13
-	D031 = P0_31 // AIN7
-	D029 = P0_29 // AIN5
-	D002 = P0_02 // AIN0
-
-	D111 = P1_11
-	D010 = P0_10 // NFC2
-	D009 = P0_09 // NFC1
-
-	D026 = P0_26
-	D012 = P0_12
-	D101 = P1_01
-	D102 = P1_02
-	D107 = P1_07
-)
-
-// Analog Pins
-const (
-	AIN2 = P0_04 // Battery
-	AIN7 = P0_31
-	AIN5 = P0_29
-	AIN0 = P0_02
-)
-
-const (
-	LED = P0_15
-)
-
-// UART0 pins (logical UART1)
-const (
-	UART_RX_PIN = P0_06
-	UART_TX_PIN = P0_08
-)
-
-// UART0 is the USB device
-var (
-	UART0 = USB
-)
-
-// I2C pins
-const (
-	SDA_PIN = P0_17 // I2C0 external
-	SCL_PIN = P0_20 // I2C0 external
-)
-
-// SPI pins
-const (
-	SPI0_SCK_PIN = P0_22 // SCK
-	SPI0_SDO_PIN = P0_24 // SDO
-	SPI0_SDI_PIN = P1_00 // SDI
-)
-
-// USB CDC identifiers
-const (
-	usb_STRING_PRODUCT      = "nice!nano"
-	usb_STRING_MANUFACTURER = "Nice Keyboards"
-)
-
-var (
-	usb_VID uint16 = 0x239A
-	usb_PID uint16 = 0x0029
-)

src/machine/board_nrf52840-mdk-usb-dongle.go

@@ -1,53 +0,0 @@
-// +build nrf52840_mdk_usb_dongle
-
-package machine
-
-const HasLowFrequencyCrystal = true
-
-// LEDs on the nrf52840-mdk-usb-dongle
-const (
-	LED       Pin = LED_GREEN
-	LED_GREEN Pin = 22
-	LED_RED   Pin = 23
-	LED_BLUE  Pin = 24
-)
-
-// RESET/USR button, depending on value of PSELRESET UICR register
-const (
-	BUTTON Pin = 18
-)
-
-// UART pins
-const (
-	UART_TX_PIN Pin = NoPin
-	UART_RX_PIN Pin = NoPin
-)
-
-// UART0 is the USB device
-var (
-	UART0 = USB
-)
-
-// I2C pins (unused)
-const (
-	SDA_PIN = NoPin
-	SCL_PIN = NoPin
-)
-
-// SPI pins (unused)
-const (
-	SPI0_SCK_PIN = NoPin
-	SPI0_SDO_PIN = NoPin
-	SPI0_SDI_PIN = NoPin
-)
-
-// USB CDC identifiers
-const (
-	usb_STRING_PRODUCT      = "Makerdiary nRF52840 MDK USB Dongle"
-	usb_STRING_MANUFACTURER = "Makerdiary"
-)
-
-var (
-	usb_VID uint16 = 0x1915
-	usb_PID uint16 = 0xCAFE
-)

src/machine/board_nrf52840-mdk.go

@@ -38,7 +38,7 @@ const (
 
 // USB CDC identifiers
 const (
-	usb_STRING_PRODUCT      = "Makerdiary nRF52840 MDK"
+	usb_STRING_PRODUCT      = "Makerdiary nRF52840 MDK USB Dongle"
 	usb_STRING_MANUFACTURER = "Makerdiary"
 )
 

src/machine/board_nucleof103rb.go

@@ -120,6 +120,6 @@ const (
 
 // I2C pins
 const (
-	I2C0_SCL_PIN = PB6
-	I2C0_SDA_PIN = PB7
+	SCL_PIN = PB6
+	SDA_PIN = PB7
 )

src/machine/board_nucleol552ze.go

@@ -1,45 +0,0 @@
-// +build nucleol552ze
-
-package machine
-
-import (
-	"device/stm32"
-	"runtime/interrupt"
-)
-
-const (
-	LED         = LED_BUILTIN
-	LED_BUILTIN = LED_GREEN
-	LED_GREEN   = PC7
-	LED_BLUE    = PB7
-	LED_RED     = PA9
-)
-
-const (
-	BUTTON      = BUTTON_USER
-	BUTTON_USER = PC13
-)
-
-// UART pins
-const (
-	// PG7 and PG8 are connected to the ST-Link Virtual Com Port (VCP)
-	UART_TX_PIN = PG7
-	UART_RX_PIN = PG8
-	UART_ALT_FN = 8 // GPIO_AF8_LPUART1
-)
-
-var (
-	// LPUART1 is the hardware serial port connected to the onboard ST-LINK
-	// debugger to be exposed as virtual COM port over USB on Nucleo boards.
-	// Both UART0 and UART1 refer to LPUART1.
-	UART0 = UART{
-		Buffer:          NewRingBuffer(),
-		Bus:             stm32.LPUART1,
-		AltFuncSelector: UART_ALT_FN,
-	}
-	UART1 = &UART0
-)
-
-func init() {
-	UART0.Interrupt = interrupt.New(stm32.IRQ_LPUART1, UART0.handleInterrupt)
-}

src/machine/board_stm32.go

@@ -0,0 +1,5 @@
+// +build bluepill nucleof103rb stm32f4
+
+package machine
+
+// Peripheral abstraction layer for the stm32.

src/machine/board_stm32f4disco.go

@@ -66,15 +66,3 @@ var (
 	}
 	SPI1 = &SPI0
 )
-
-const (
-	I2C0_SCL_PIN = PB6
-	I2C0_SDA_PIN = PB9
-)
-
-var (
-	I2C0 = I2C{
-		Bus:             stm32.I2C1,
-		AltFuncSelector: AF4_I2C1_2_3,
-	}
-)

src/machine/board_teensy40.go

@@ -136,11 +136,9 @@ const (
 )
 
 var (
-	UART0 = &UART1 // alias UART0 to UART1
 	UART1 = UART{
-		Bus:      nxp.LPUART6,
-		Buffer:   NewRingBuffer(),
-		txBuffer: NewRingBuffer(),
+		Buffer: NewRingBuffer(),
+		Bus:    nxp.LPUART6,
 		muxRX: muxSelect{ // D0 (PA3 [AD_B0_03])
 			mux: nxp.IOMUXC_LPUART6_RX_SELECT_INPUT_DAISY_GPIO_AD_B0_03_ALT2,
 			sel: &nxp.IOMUXC.LPUART6_RX_SELECT_INPUT,
@@ -151,9 +149,8 @@ var (
 		},
 	}
 	UART2 = UART{
-		Bus:      nxp.LPUART4,
-		Buffer:   NewRingBuffer(),
-		txBuffer: NewRingBuffer(),
+		Buffer: NewRingBuffer(),
+		Bus:    nxp.LPUART4,
 		muxRX: muxSelect{ // D7 (PB17 [B1_01])
 			mux: nxp.IOMUXC_LPUART4_RX_SELECT_INPUT_DAISY_GPIO_B1_01_ALT2,
 			sel: &nxp.IOMUXC.LPUART4_RX_SELECT_INPUT,
@@ -164,9 +161,8 @@ var (
 		},
 	}
 	UART3 = UART{
-		Bus:      nxp.LPUART2,
-		Buffer:   NewRingBuffer(),
-		txBuffer: NewRingBuffer(),
+		Buffer: NewRingBuffer(),
+		Bus:    nxp.LPUART2,
 		muxRX: muxSelect{ // D15 (PA19 [AD_B1_03])
 			mux: nxp.IOMUXC_LPUART2_RX_SELECT_INPUT_DAISY_GPIO_AD_B1_03_ALT2,
 			sel: &nxp.IOMUXC.LPUART2_RX_SELECT_INPUT,
@@ -177,9 +173,8 @@ var (
 		},
 	}
 	UART4 = UART{
-		Bus:      nxp.LPUART3,
-		Buffer:   NewRingBuffer(),
-		txBuffer: NewRingBuffer(),
+		Buffer: NewRingBuffer(),
+		Bus:    nxp.LPUART3,
 		muxRX: muxSelect{ // D16 (PA23 [AD_B1_07])
 			mux: nxp.IOMUXC_LPUART3_RX_SELECT_INPUT_DAISY_GPIO_AD_B1_07_ALT2,
 			sel: &nxp.IOMUXC.LPUART3_RX_SELECT_INPUT,
@@ -190,9 +185,8 @@ var (
 		},
 	}
 	UART5 = UART{
-		Bus:      nxp.LPUART8,
-		Buffer:   NewRingBuffer(),
-		txBuffer: NewRingBuffer(),
+		Buffer: NewRingBuffer(),
+		Bus:    nxp.LPUART8,
 		muxRX: muxSelect{ // D21 (PA27 [AD_B1_11])
 			mux: nxp.IOMUXC_LPUART8_RX_SELECT_INPUT_DAISY_GPIO_AD_B1_11_ALT2,
 			sel: &nxp.IOMUXC.LPUART8_RX_SELECT_INPUT,
@@ -203,17 +197,15 @@ var (
 		},
 	}
 	UART6 = UART{
-		Bus:      nxp.LPUART1,
-		Buffer:   NewRingBuffer(),
-		txBuffer: NewRingBuffer(),
+		Buffer: NewRingBuffer(),
+		Bus:    nxp.LPUART1,
 		// LPUART1 not connected via IOMUXC
 		//   RX: D24 (PA12 [AD_B0_12])
 		//   TX: D25 (PA13 [AD_B0_13])
 	}
 	UART7 = UART{
-		Bus:      nxp.LPUART7,
-		Buffer:   NewRingBuffer(),
-		txBuffer: NewRingBuffer(),
+		Buffer: NewRingBuffer(),
+		Bus:    nxp.LPUART7,
 		muxRX: muxSelect{ // D28 (PC18 [EMC_32])
 			mux: nxp.IOMUXC_LPUART7_RX_SELECT_INPUT_DAISY_GPIO_EMC_32_ALT2,
 			sel: &nxp.IOMUXC.LPUART7_RX_SELECT_INPUT,

src/machine/i2c.go

@@ -1,4 +1,4 @@
-// +build avr nrf sam stm32,!stm32f7x2,!stm32l5x2,!stm32l0 fe310 k210
+// +build avr nrf sam stm32,!stm32f407,!stm32f7x2,!stm32l0 fe310 k210
 
 package machine
 

src/machine/machine_atmega.go

@@ -5,8 +5,6 @@ package machine
 import (
 	"device/avr"
 	"runtime/interrupt"
-	"runtime/volatile"
-	"unsafe"
 )
 
 // I2CConfig is used to store config info for I2C.
@@ -15,7 +13,7 @@ type I2CConfig struct {
 }
 
 // Configure is intended to setup the I2C interface.
-func (i2c I2C) Configure(config I2CConfig) error {
+func (i2c I2C) Configure(config I2CConfig) {
 	// Default I2C bus speed is 100 kHz.
 	if config.Frequency == 0 {
 		config.Frequency = TWI_FREQ_100KHZ
@@ -35,8 +33,6 @@ func (i2c I2C) Configure(config I2CConfig) error {
 
 	// Enable twi module.
 	avr.TWCR.Set(avr.TWCR_TWEN)
-
-	return nil
 }
 
 // Tx does a single I2C transaction at the specified address.
@@ -114,12 +110,6 @@ func (i2c I2C) readByte() byte {
 	return byte(avr.TWDR.Get())
 }
 
-// UART
-var (
-	// UART0 is the hardware serial port on the AVR.
-	UART0 = UART{Buffer: NewRingBuffer()}
-)
-
 // UART on the AVR.
 type UART struct {
 	Buffer *RingBuffer
@@ -165,108 +155,3 @@ func (uart UART) WriteByte(c byte) error {
 	avr.UDR0.Set(c) // send char
 	return nil
 }
-
-// SPIConfig is used to store config info for SPI.
-type SPIConfig struct {
-	Frequency uint32
-	LSBFirst  bool
-	Mode      uint8
-}
-
-// SPI is for the Serial Peripheral Interface
-// Data is taken from http://ww1.microchip.com/downloads/en/DeviceDoc/ATmega48A-PA-88A-PA-168A-PA-328-P-DS-DS40002061A.pdf page 169 and following
-type SPI struct {
-	// The registers for the SPIx port set by the chip
-	spcr *volatile.Register8
-	spdr *volatile.Register8
-	spsr *volatile.Register8
-
-	// The io pins for the SPIx port set by the chip
-	sck Pin
-	sdi Pin
-	sdo Pin
-	cs  Pin
-}
-
-// Configure is intended to setup the SPI interface.
-func (s SPI) Configure(config SPIConfig) error {
-
-	// This is only here to help catch a bug with the configuration
-	// where a machine missed a value.
-	if s.spcr == (*volatile.Register8)(unsafe.Pointer(uintptr(0))) ||
-		s.spsr == (*volatile.Register8)(unsafe.Pointer(uintptr(0))) ||
-		s.spdr == (*volatile.Register8)(unsafe.Pointer(uintptr(0))) ||
-		s.sck == 0 || s.sdi == 0 || s.sdo == 0 || s.cs == 0 {
-		return errSPIInvalidMachineConfig
-	}
-
-	// Make the defaults meaningful
-	if config.Frequency == 0 {
-		config.Frequency = 4000000
-	}
-
-	// Default all port configuration bits to 0 for simplicity
-	s.spcr.Set(0)
-	s.spsr.Set(0)
-
-	// Setup pins output configuration
-	s.sck.Configure(PinConfig{Mode: PinOutput})
-	s.sdi.Configure(PinConfig{Mode: PinInput})
-	s.sdo.Configure(PinConfig{Mode: PinOutput})
-
-	// Prevent CS glitches if the pin is enabled Low (0, default)
-	s.cs.High()
-	// If the CS pin is not configured as output the SPI port operates in
-	// slave mode.
-	s.cs.Configure(PinConfig{Mode: PinOutput})
-
-	frequencyDivider := CPUFrequency() / config.Frequency
-
-	switch {
-	case frequencyDivider >= 128:
-		s.spcr.SetBits(avr.SPCR_SPR0 | avr.SPCR_SPR1)
-	case frequencyDivider >= 64:
-		s.spcr.SetBits(avr.SPCR_SPR1)
-	case frequencyDivider >= 32:
-		s.spcr.SetBits(avr.SPCR_SPR1)
-		s.spsr.SetBits(avr.SPSR_SPI2X)
-	case frequencyDivider >= 16:
-		s.spcr.SetBits(avr.SPCR_SPR0)
-	case frequencyDivider >= 8:
-		s.spcr.SetBits(avr.SPCR_SPR0)
-		s.spsr.SetBits(avr.SPSR_SPI2X)
-	case frequencyDivider >= 4:
-		// The clock is already set to all 0's.
-	default: // defaults to fastest which is /2
-		s.spsr.SetBits(avr.SPSR_SPI2X)
-	}
-
-	switch config.Mode {
-	case Mode1:
-		s.spcr.SetBits(avr.SPCR_CPHA)
-	case Mode2:
-		s.spcr.SetBits(avr.SPCR_CPOL)
-	case Mode3:
-		s.spcr.SetBits(avr.SPCR_CPHA | avr.SPCR_CPOL)
-	default: // default is mode 0
-	}
-
-	if config.LSBFirst {
-		s.spcr.SetBits(avr.SPCR_DORD)
-	}
-
-	// enable SPI, set controller, set clock rate
-	s.spcr.SetBits(avr.SPCR_SPE | avr.SPCR_MSTR)
-
-	return nil
-}
-
-// Transfer writes the byte into the register and returns the read content
-func (s SPI) Transfer(b byte) (byte, error) {
-	s.spdr.Set(uint8(b))
-
-	for !s.spsr.HasBits(avr.SPSR_SPIF) {
-	}
-
-	return byte(s.spdr.Get()), nil
-}

src/machine/machine_atmega1284p.go

@@ -69,13 +69,3 @@ func (p Pin) getPortMask() (*volatile.Register8, uint8) {
 		return avr.PORTD, 1 << uint8(p-portD)
 	}
 }
-
-// SPI configuration
-var SPI0 = SPI{
-	spcr: avr.SPCR,
-	spsr: avr.SPSR,
-	spdr: avr.SPDR,
-	sck:  PB7,
-	sdo:  PB5,
-	sdi:  PB6,
-	cs:   PB4}

src/machine/machine_atmega2560.go

@@ -126,13 +126,3 @@ func (p Pin) getPortMask() (*volatile.Register8, uint8) {
 		return avr.PORTA, 255
 	}
 }
-
-// SPI configuration
-var SPI0 = SPI{
-	spcr: avr.SPCR,
-	spdr: avr.SPDR,
-	spsr: avr.SPSR,
-	sck:  PB1,
-	sdo:  PB2,
-	sdi:  PB3,
-	cs:   PB0}

src/machine/machine_atmega328p.go

@@ -88,13 +88,3 @@ func (pwm PWM) Set(value uint16) {
 		panic("Invalid PWM pin")
 	}
 }
-
-// SPI configuration
-var SPI0 = SPI{
-	spcr: avr.SPCR,
-	spdr: avr.SPDR,
-	spsr: avr.SPSR,
-	sck:  PB5,
-	sdo:  PB3,
-	sdi:  PB4,
-	cs:   PB2}

src/machine/machine_atmega328pb.go

@@ -1,109 +0,0 @@
-// +build avr,atmega328pb
-
-package machine
-
-import (
-	"device/avr"
-	"runtime/volatile"
-)
-
-const irq_USART0_RX = avr.IRQ_USART0_RX
-
-// getPortMask returns the PORTx register and mask for the pin.
-func (p Pin) getPortMask() (*volatile.Register8, uint8) {
-	switch {
-	case p >= PB0 && p <= PB7: // port B
-		return avr.PORTB, 1 << uint8(p-portB)
-	case p >= PC0 && p <= PC7: // port C
-		return avr.PORTC, 1 << uint8(p-portC)
-	default: // port D
-		return avr.PORTD, 1 << uint8(p-portD)
-	}
-}
-
-// InitPWM initializes the registers needed for PWM.
-func InitPWM() {
-	// use waveform generation
-	avr.TCCR0A.SetBits(avr.TCCR0A_WGM00)
-
-	// set timer 0 prescale factor to 64
-	avr.TCCR0B.SetBits(avr.TCCR0B_CS01 | avr.TCCR0B_CS00)
-
-	// set timer 1 prescale factor to 64
-	avr.TCCR1B.SetBits(avr.TCCR1B_CS11)
-
-	// put timer 1 in 8-bit phase correct pwm mode
-	avr.TCCR1A.SetBits(avr.TCCR1A_WGM10)
-
-	// set timer 2 prescale factor to 64
-	avr.TCCR2B.SetBits(avr.TCCR2B_CS22)
-
-	// configure timer 2 for phase correct pwm (8-bit)
-	avr.TCCR2A.SetBits(avr.TCCR2A_WGM20)
-}
-
-// Configure configures a PWM pin for output.
-func (pwm PWM) Configure() error {
-	switch pwm.Pin / 8 {
-	case 0: // port B
-		avr.DDRB.SetBits(1 << uint8(pwm.Pin))
-	case 2: // port D
-		avr.DDRD.SetBits(1 << uint8(pwm.Pin-16))
-	}
-	return nil
-}
-
-// Set turns on the duty cycle for a PWM pin using the provided value. On the AVR this is normally a
-// 8-bit value ranging from 0 to 255.
-func (pwm PWM) Set(value uint16) {
-	value8 := uint8(value >> 8)
-	switch pwm.Pin {
-	case PD3:
-		// connect pwm to pin on timer 2, channel B
-		avr.TCCR2A.SetBits(avr.TCCR2A_COM2B1)
-		avr.OCR2B.Set(value8) // set pwm duty
-	case PD5:
-		// connect pwm to pin on timer 0, channel B
-		avr.TCCR0A.SetBits(avr.TCCR0A_COM0B1)
-		avr.OCR0B.Set(value8) // set pwm duty
-	case PD6:
-		// connect pwm to pin on timer 0, channel A
-		avr.TCCR0A.SetBits(avr.TCCR0A_COM0A1)
-		avr.OCR0A.Set(value8) // set pwm duty
-	case PB1:
-		// connect pwm to pin on timer 1, channel A
-		avr.TCCR1A.SetBits(avr.TCCR1A_COM1A1)
-		// this is a 16-bit value, but we only currently allow the low order bits to be set
-		avr.OCR1AL.Set(value8) // set pwm duty
-	case PB2:
-		// connect pwm to pin on timer 1, channel B
-		avr.TCCR1A.SetBits(avr.TCCR1A_COM1B1)
-		// this is a 16-bit value, but we only currently allow the low order bits to be set
-		avr.OCR1BL.Set(value8) // set pwm duty
-	case PB3:
-		// connect pwm to pin on timer 2, channel A
-		avr.TCCR2A.SetBits(avr.TCCR2A_COM2A1)
-		avr.OCR2A.Set(value8) // set pwm duty
-	default:
-		panic("Invalid PWM pin")
-	}
-}
-
-// SPI configuration
-var SPI0 = SPI{
-	spcr: avr.SPCR0,
-	spdr: avr.SPDR0,
-	spsr: avr.SPSR0,
-	sck:  PB5,
-	sdo:  PB3,
-	sdi:  PB4,
-	cs:   PB2}
-
-var SPI1 = SPI{
-	spcr: avr.SPCR1,
-	spdr: avr.SPDR1,
-	spsr: avr.SPSR1,
-	sck:  PC1,
-	sdo:  PE3,
-	sdi:  PC0,
-	cs:   PE2}

src/machine/machine_atsamd21.go

@@ -8,12 +8,9 @@
 package machine
 
 import (
-	"device"
 	"device/arm"
 	"device/sam"
-	"errors"
 	"runtime/interrupt"
-	"runtime/volatile"
 	"unsafe"
 )
 
@@ -310,30 +307,13 @@ func InitADC() {
 
 	// set calibration
 	sam.ADC.CALIB.Set((bias << 8) | linearity)
-}
-
-// Configure configures a ADC pin to be able to be used to read data.
-func (a ADC) Configure(config ADCConfig) {
 
 	// Wait for synchronization
 	waitADCSync()
 
-	var resolution uint32
-	switch config.Resolution {
-	case 8:
-		resolution = sam.ADC_CTRLB_RESSEL_8BIT
-	case 10:
-		resolution = sam.ADC_CTRLB_RESSEL_10BIT
-	case 12:
-		resolution = sam.ADC_CTRLB_RESSEL_12BIT
-	case 16:
-		resolution = sam.ADC_CTRLB_RESSEL_16BIT
-	default:
-		resolution = sam.ADC_CTRLB_RESSEL_12BIT
-	}
 	// Divide Clock by 32 with 12 bits resolution as default
 	sam.ADC.CTRLB.Set((sam.ADC_CTRLB_PRESCALER_DIV32 << sam.ADC_CTRLB_PRESCALER_Pos) |
-		uint16(resolution<<sam.ADC_CTRLB_RESSEL_Pos))
+		(sam.ADC_CTRLB_RESSEL_12BIT << sam.ADC_CTRLB_RESSEL_Pos))
 
 	// Sampling Time Length
 	sam.ADC.SAMPCTRL.Set(5)
@@ -345,44 +325,18 @@ func (a ADC) Configure(config ADCConfig) {
 	sam.ADC.INPUTCTRL.Set(sam.ADC_INPUTCTRL_MUXNEG_GND << sam.ADC_INPUTCTRL_MUXNEG_Pos)
 
 	// Averaging (see datasheet table in AVGCTRL register description)
-	var samples uint32
-	switch config.Samples {
-	case 1:
-		samples = sam.ADC_AVGCTRL_SAMPLENUM_1
-	case 2:
-		samples = sam.ADC_AVGCTRL_SAMPLENUM_2
-	case 4:
-		samples = sam.ADC_AVGCTRL_SAMPLENUM_4
-	case 8:
-		samples = sam.ADC_AVGCTRL_SAMPLENUM_8
-	case 16:
-		samples = sam.ADC_AVGCTRL_SAMPLENUM_16
-	case 32:
-		samples = sam.ADC_AVGCTRL_SAMPLENUM_32
-	case 64:
-		samples = sam.ADC_AVGCTRL_SAMPLENUM_64
-	case 128:
-		samples = sam.ADC_AVGCTRL_SAMPLENUM_128
-	case 256:
-		samples = sam.ADC_AVGCTRL_SAMPLENUM_256
-	case 512:
-		samples = sam.ADC_AVGCTRL_SAMPLENUM_512
-	case 1024:
-		samples = sam.ADC_AVGCTRL_SAMPLENUM_1024
-	default:
-		samples = sam.ADC_AVGCTRL_SAMPLENUM_1
-	}
-	sam.ADC.AVGCTRL.Set(uint8(samples<<sam.ADC_AVGCTRL_SAMPLENUM_Pos) |
+	sam.ADC.AVGCTRL.Set((sam.ADC_AVGCTRL_SAMPLENUM_1 << sam.ADC_AVGCTRL_SAMPLENUM_Pos) |
 		(0x0 << sam.ADC_AVGCTRL_ADJRES_Pos))
 
-	// TODO: use config.Reference to set AREF level
-
 	// Analog Reference is AREF pin (3.3v)
 	sam.ADC.INPUTCTRL.SetBits(sam.ADC_INPUTCTRL_GAIN_DIV2 << sam.ADC_INPUTCTRL_GAIN_Pos)
 
 	// 1/2 VDDANA = 0.5 * 3V3 = 1.65V
 	sam.ADC.REFCTRL.SetBits(sam.ADC_REFCTRL_REFSEL_INTVCC1 << sam.ADC_REFCTRL_REFSEL_Pos)
+}
 
+// Configure configures a ADCPin to be able to be used to read data.
+func (a ADC) Configure() {
 	a.Pin.Configure(PinConfig{Mode: PinAnalog})
 	return
 }
@@ -1267,160 +1221,6 @@ func (spi SPI) Transfer(w byte) (byte, error) {
 	return byte(spi.Bus.DATA.Get()), nil
 }
 
-var (
-	ErrTxInvalidSliceSize = errors.New("SPI write and read slices must be same size")
-)
-
-// Tx handles read/write operation for SPI interface. Since SPI is a syncronous write/read
-// interface, there must always be the same number of bytes written as bytes read.
-// The Tx method knows about this, and offers a few different ways of calling it.
-//
-// This form sends the bytes in tx buffer, putting the resulting bytes read into the rx buffer.
-// Note that the tx and rx buffers must be the same size:
-//
-// 		spi.Tx(tx, rx)
-//
-// This form sends the tx buffer, ignoring the result. Useful for sending "commands" that return zeros
-// until all the bytes in the command packet have been received:
-//
-// 		spi.Tx(tx, nil)
-//
-// This form sends zeros, putting the result into the rx buffer. Good for reading a "result packet":
-//
-// 		spi.Tx(nil, rx)
-//
-func (spi SPI) Tx(w, r []byte) error {
-	if spi.Bus.BAUD.Get() == 0x00 {
-		// When the SPI Freq is 24MHz, special processing is performed to improve the speed.
-
-		switch {
-		case w == nil:
-			// read only, so write zero and read a result.
-			spi.rx(r)
-		case r == nil:
-			// write only
-			spi.tx24mhz(w)
-
-		default:
-			// write/read
-			if len(w) != len(r) {
-				return ErrTxInvalidSliceSize
-			}
-
-			spi.txrx24mhz(w, r)
-		}
-
-	} else {
-		switch {
-		case w == nil:
-			// read only, so write zero and read a result.
-			spi.rx(r)
-		case r == nil:
-			// write only
-			spi.tx(w)
-
-		default:
-			// write/read
-			if len(w) != len(r) {
-				return ErrTxInvalidSliceSize
-			}
-
-			spi.txrx(w, r)
-		}
-	}
-
-	return nil
-}
-
-func (spi SPI) tx(tx []byte) {
-	for i := 0; i < len(tx); i++ {
-		for !spi.Bus.INTFLAG.HasBits(sam.SERCOM_SPI_INTFLAG_DRE) {
-		}
-		spi.Bus.DATA.Set(uint32(tx[i]))
-	}
-	for !spi.Bus.INTFLAG.HasBits(sam.SERCOM_SPI_INTFLAG_TXC) {
-	}
-
-	// read to clear RXC register
-	for spi.Bus.INTFLAG.HasBits(sam.SERCOM_SPI_INTFLAG_RXC) {
-		spi.Bus.DATA.Get()
-	}
-}
-
-func (spi SPI) rx(rx []byte) {
-	spi.Bus.DATA.Set(0)
-	for !spi.Bus.INTFLAG.HasBits(sam.SERCOM_SPI_INTFLAG_DRE) {
-	}
-
-	for i := 1; i < len(rx); i++ {
-		spi.Bus.DATA.Set(0)
-		for !spi.Bus.INTFLAG.HasBits(sam.SERCOM_SPI_INTFLAG_RXC) {
-		}
-		rx[i-1] = byte(spi.Bus.DATA.Get())
-	}
-	for !spi.Bus.INTFLAG.HasBits(sam.SERCOM_SPI_INTFLAG_RXC) {
-	}
-	rx[len(rx)-1] = byte(spi.Bus.DATA.Get())
-}
-
-func (spi SPI) txrx(tx, rx []byte) {
-	spi.Bus.DATA.Set(uint32(tx[0]))
-	for !spi.Bus.INTFLAG.HasBits(sam.SERCOM_SPI_INTFLAG_DRE) {
-	}
-
-	for i := 1; i < len(rx); i++ {
-		spi.Bus.DATA.Set(uint32(tx[i]))
-		for !spi.Bus.INTFLAG.HasBits(sam.SERCOM_SPI_INTFLAG_RXC) {
-		}
-		rx[i-1] = byte(spi.Bus.DATA.Get())
-	}
-	for !spi.Bus.INTFLAG.HasBits(sam.SERCOM_SPI_INTFLAG_RXC) {
-	}
-	rx[len(rx)-1] = byte(spi.Bus.DATA.Get())
-}
-
-// tx24mhz is a special tx/rx function for CPU Clock 48 Mhz and SPI Freq 24 Mhz
-func (spi SPI) tx24mhz(tx []byte) {
-	spi.Bus.DATA.Set(uint32(tx[0]))
-	device.Asm("nop")
-	device.Asm("nop")
-	device.Asm("nop")
-	device.Asm("nop")
-	device.Asm("nop")
-	device.Asm("nop")
-
-	for i := 1; i < len(tx); i++ {
-		spi.Bus.DATA.Set(uint32(tx[i]))
-		device.Asm("nop")
-		device.Asm("nop")
-		spi.Bus.DATA.Get()
-	}
-	for !spi.Bus.INTFLAG.HasBits(sam.SERCOM_SPI_INTFLAG_RXC) {
-	}
-	spi.Bus.DATA.Get()
-}
-
-// txrx24mhz is a special tx/rx function for CPU Clock 48 Mhz and SPI Freq 24 Mhz
-func (spi SPI) txrx24mhz(tx, rx []byte) {
-	spi.Bus.DATA.Set(uint32(tx[0]))
-	device.Asm("nop")
-	device.Asm("nop")
-	device.Asm("nop")
-	device.Asm("nop")
-	device.Asm("nop")
-	device.Asm("nop")
-
-	for i := 1; i < len(rx); i++ {
-		spi.Bus.DATA.Set(uint32(tx[i]))
-		device.Asm("nop")
-		device.Asm("nop")
-		rx[i-1] = byte(spi.Bus.DATA.Get())
-	}
-	for !spi.Bus.INTFLAG.HasBits(sam.SERCOM_SPI_INTFLAG_RXC) {
-	}
-	rx[len(rx)-1] = byte(spi.Bus.DATA.Get())
-}
-
 // PWM
 const period = 0xFFFF
 
@@ -1621,104 +1421,36 @@ func (pwm PWM) setChannel(timer *sam.TCC_Type, val uint32) {
 
 // USBCDC is the USB CDC aka serial over USB interface on the SAMD21.
 type USBCDC struct {
-	Buffer            *RingBuffer
-	TxIdx             volatile.Register8
-	waitTxc           bool
-	waitTxcRetryCount uint8
-	sent              bool
-}
-
-const (
-	usbcdcTxSizeMask          uint8 = 0x3F
-	usbcdcTxBankMask          uint8 = ^usbcdcTxSizeMask
-	usbcdcTxBank1st           uint8 = 0x00
-	usbcdcTxBank2nd           uint8 = usbcdcTxSizeMask + 1
-	usbcdcTxMaxRetriesAllowed uint8 = 5
-)
-
-// Flush flushes buffered data.
-func (usbcdc *USBCDC) Flush() error {
-	if usbLineInfo.lineState > 0 {
-		idx := usbcdc.TxIdx.Get()
-		sz := idx & usbcdcTxSizeMask
-		bk := idx & usbcdcTxBankMask
-		if 0 < sz {
-
-			if usbcdc.waitTxc {
-				// waiting for the next flush(), because the transmission is not complete
-				return nil
-			}
-			usbcdc.waitTxc = true
-			usbcdc.waitTxcRetryCount = 0
-
-			// set the data
-			usbEndpointDescriptors[usb_CDC_ENDPOINT_IN].DeviceDescBank[1].ADDR.Set(uint32(uintptr(unsafe.Pointer(&udd_ep_in_cache_buffer[usb_CDC_ENDPOINT_IN][bk]))))
-			if bk == usbcdcTxBank1st {
-				usbcdc.TxIdx.Set(usbcdcTxBank2nd)
-			} else {
-				usbcdc.TxIdx.Set(usbcdcTxBank1st)
-			}
-
-			// clean multi packet size of bytes already sent
-			usbEndpointDescriptors[usb_CDC_ENDPOINT_IN].DeviceDescBank[1].PCKSIZE.ClearBits(usb_DEVICE_PCKSIZE_MULTI_PACKET_SIZE_Mask << usb_DEVICE_PCKSIZE_MULTI_PACKET_SIZE_Pos)
-
-			// set count of bytes to be sent
-			usbEndpointDescriptors[usb_CDC_ENDPOINT_IN].DeviceDescBank[1].PCKSIZE.ClearBits(usb_DEVICE_PCKSIZE_BYTE_COUNT_Mask << usb_DEVICE_PCKSIZE_BYTE_COUNT_Pos)
-			usbEndpointDescriptors[usb_CDC_ENDPOINT_IN].DeviceDescBank[1].PCKSIZE.SetBits((uint32(sz) & usb_DEVICE_PCKSIZE_BYTE_COUNT_Mask) << usb_DEVICE_PCKSIZE_BYTE_COUNT_Pos)
-
-			// clear transfer complete flag
-			setEPINTFLAG(usb_CDC_ENDPOINT_IN, sam.USB_DEVICE_EPINTFLAG_TRCPT1)
-
-			// send data by setting bank ready
-			setEPSTATUSSET(usb_CDC_ENDPOINT_IN, sam.USB_DEVICE_EPSTATUSSET_BK1RDY)
-			UART0.sent = true
-		}
-	}
-	return nil
+	Buffer *RingBuffer
 }
 
 // WriteByte writes a byte of data to the USB CDC interface.
-func (usbcdc *USBCDC) WriteByte(c byte) error {
+func (usbcdc USBCDC) WriteByte(c byte) error {
 	// Supposedly to handle problem with Windows USB serial ports?
 	if usbLineInfo.lineState > 0 {
-		ok := false
-		for {
-			mask := interrupt.Disable()
+		// set the data
+		udd_ep_in_cache_buffer[usb_CDC_ENDPOINT_IN][0] = c
 
-			idx := UART0.TxIdx.Get()
-			if (idx & usbcdcTxSizeMask) < usbcdcTxSizeMask {
-				udd_ep_in_cache_buffer[usb_CDC_ENDPOINT_IN][idx] = c
-				UART0.TxIdx.Set(idx + 1)
-				ok = true
-			}
+		usbEndpointDescriptors[usb_CDC_ENDPOINT_IN].DeviceDescBank[1].ADDR.Set(uint32(uintptr(unsafe.Pointer(&udd_ep_in_cache_buffer[usb_CDC_ENDPOINT_IN]))))
 
-			interrupt.Restore(mask)
+		// clean multi packet size of bytes already sent
+		usbEndpointDescriptors[usb_CDC_ENDPOINT_IN].DeviceDescBank[1].PCKSIZE.ClearBits(usb_DEVICE_PCKSIZE_MULTI_PACKET_SIZE_Mask << usb_DEVICE_PCKSIZE_MULTI_PACKET_SIZE_Pos)
 
-			if ok {
-				break
-			} else if usbcdcTxMaxRetriesAllowed < UART0.waitTxcRetryCount {
-				mask := interrupt.Disable()
-				UART0.waitTxc = false
-				UART0.waitTxcRetryCount = 0
-				usbcdc.TxIdx.Set(0)
-				usbLineInfo.lineState = 0
-				interrupt.Restore(mask)
-				break
-			} else {
-				mask := interrupt.Disable()
-				if UART0.sent {
-					if UART0.waitTxc {
-						if (getEPINTFLAG(usb_CDC_ENDPOINT_IN) & sam.USB_DEVICE_EPINTFLAG_TRCPT1) != 0 {
-							setEPSTATUSCLR(usb_CDC_ENDPOINT_IN, sam.USB_DEVICE_EPSTATUSCLR_BK1RDY)
-							setEPINTFLAG(usb_CDC_ENDPOINT_IN, sam.USB_DEVICE_EPINTFLAG_TRCPT1)
-							UART0.waitTxc = false
-							UART0.Flush()
-						}
-					} else {
-						UART0.Flush()
-					}
-				}
-				interrupt.Restore(mask)
+		// set count of bytes to be sent
+		usbEndpointDescriptors[usb_CDC_ENDPOINT_IN].DeviceDescBank[1].PCKSIZE.SetBits((1 & usb_DEVICE_PCKSIZE_BYTE_COUNT_Mask) << usb_DEVICE_PCKSIZE_BYTE_COUNT_Pos)
+
+		// clear transfer complete flag
+		setEPINTFLAG(usb_CDC_ENDPOINT_IN, sam.USB_DEVICE_EPINTFLAG_TRCPT1)
+
+		// send data by setting bank ready
+		setEPSTATUSSET(usb_CDC_ENDPOINT_IN, sam.USB_DEVICE_EPSTATUSSET_BK1RDY)
+
+		// wait for transfer to complete
+		timeout := 3000
+		for (getEPINTFLAG(usb_CDC_ENDPOINT_IN) & sam.USB_DEVICE_EPINTFLAG_TRCPT1) == 0 {
+			timeout--
+			if timeout == 0 {
+				return errUSBCDCWriteByteTimeout
 			}
 		}
 	}
@@ -1925,19 +1657,9 @@ func handleUSB(intr interrupt.Interrupt) {
 			case usb_CDC_ENDPOINT_IN, usb_CDC_ENDPOINT_ACM:
 				setEPSTATUSCLR(i, sam.USB_DEVICE_EPSTATUSCLR_BK1RDY)
 				setEPINTFLAG(i, sam.USB_DEVICE_EPINTFLAG_TRCPT1)
-
-				if i == usb_CDC_ENDPOINT_IN {
-					UART0.waitTxc = false
-				}
 			}
 		}
-
-		if i == usb_CDC_ENDPOINT_IN && UART0.waitTxc {
-			UART0.waitTxcRetryCount++
-		}
 	}
-
-	UART0.Flush()
 }
 
 func initEndpoint(ep, config uint32) {

src/machine/machine_atsamd51.go

@@ -10,9 +10,7 @@ package machine
 import (
 	"device/arm"
 	"device/sam"
-	"errors"
 	"runtime/interrupt"
-	"runtime/volatile"
 	"unsafe"
 )
 
@@ -722,83 +720,65 @@ func InitADC() {
 
 	// calibrate ADC1
 	sam.ADC1.CALIB.Set(uint16((biascomp | biasr2r | biasref) >> 16))
+
+	sam.ADC0.CTRLA.SetBits(sam.ADC_CTRLA_PRESCALER_DIV32 << sam.ADC_CTRLA_PRESCALER_Pos)
+	// adcs[i]->CTRLB.bit.RESSEL = ADC_CTRLB_RESSEL_10BIT_Val;
+	sam.ADC0.CTRLB.SetBits(sam.ADC_CTRLB_RESSEL_12BIT << sam.ADC_CTRLB_RESSEL_Pos)
+
+	// wait for sync
+	for sam.ADC0.SYNCBUSY.HasBits(sam.ADC_SYNCBUSY_CTRLB) {
+	}
+
+	// sampling Time Length
+	sam.ADC0.SAMPCTRL.Set(5)
+
+	// wait for sync
+	for sam.ADC0.SYNCBUSY.HasBits(sam.ADC_SYNCBUSY_SAMPCTRL) {
+	}
+
+	// No Negative input (Internal Ground)
+	sam.ADC0.INPUTCTRL.Set(sam.ADC_INPUTCTRL_MUXNEG_GND << sam.ADC_INPUTCTRL_MUXNEG_Pos)
+
+	// wait for sync
+	for sam.ADC0.SYNCBUSY.HasBits(sam.ADC_SYNCBUSY_INPUTCTRL) {
+	}
+
+	// Averaging (see datasheet table in AVGCTRL register description)
+	// 1 sample only (no oversampling nor averaging), adjusting result by 0
+	sam.ADC0.AVGCTRL.Set(sam.ADC_AVGCTRL_SAMPLENUM_1 | (0 << sam.ADC_AVGCTRL_ADJRES_Pos))
+
+	// wait for sync
+	for sam.ADC0.SYNCBUSY.HasBits(sam.ADC_SYNCBUSY_AVGCTRL) {
+	}
+
+	// same for ADC1, as for ADC0
+	sam.ADC1.CTRLA.SetBits(sam.ADC_CTRLA_PRESCALER_DIV32 << sam.ADC_CTRLA_PRESCALER_Pos)
+	sam.ADC1.CTRLB.SetBits(sam.ADC_CTRLB_RESSEL_12BIT << sam.ADC_CTRLB_RESSEL_Pos)
+	for sam.ADC1.SYNCBUSY.HasBits(sam.ADC_SYNCBUSY_CTRLB) {
+	}
+	sam.ADC1.SAMPCTRL.Set(5)
+	for sam.ADC1.SYNCBUSY.HasBits(sam.ADC_SYNCBUSY_SAMPCTRL) {
+	}
+	sam.ADC1.INPUTCTRL.Set(sam.ADC_INPUTCTRL_MUXNEG_GND << sam.ADC_INPUTCTRL_MUXNEG_Pos)
+	for sam.ADC1.SYNCBUSY.HasBits(sam.ADC_SYNCBUSY_INPUTCTRL) {
+	}
+	sam.ADC1.AVGCTRL.Set(sam.ADC_AVGCTRL_SAMPLENUM_1 | (0 << sam.ADC_AVGCTRL_ADJRES_Pos))
+	for sam.ADC1.SYNCBUSY.HasBits(sam.ADC_SYNCBUSY_AVGCTRL) {
+	}
+
+	// wait for sync
+	for sam.ADC0.SYNCBUSY.HasBits(sam.ADC_SYNCBUSY_REFCTRL) {
+	}
+	for sam.ADC1.SYNCBUSY.HasBits(sam.ADC_SYNCBUSY_REFCTRL) {
+	}
+
+	// default is 3V3 reference voltage
+	sam.ADC0.REFCTRL.SetBits(sam.ADC_REFCTRL_REFSEL_INTVCC1)
+	sam.ADC1.REFCTRL.SetBits(sam.ADC_REFCTRL_REFSEL_INTVCC1)
 }
 
 // Configure configures a ADCPin to be able to be used to read data.
-func (a ADC) Configure(config ADCConfig) {
-
-	for _, adc := range []*sam.ADC_Type{sam.ADC0, sam.ADC1} {
-
-		for adc.SYNCBUSY.HasBits(sam.ADC_SYNCBUSY_CTRLB) {
-		} // wait for sync
-
-		adc.CTRLA.SetBits(sam.ADC_CTRLA_PRESCALER_DIV32 << sam.ADC_CTRLA_PRESCALER_Pos)
-		var resolution uint32
-		switch config.Resolution {
-		case 8:
-			resolution = sam.ADC_CTRLB_RESSEL_8BIT
-		case 10:
-			resolution = sam.ADC_CTRLB_RESSEL_10BIT
-		case 12:
-			resolution = sam.ADC_CTRLB_RESSEL_12BIT
-		case 16:
-			resolution = sam.ADC_CTRLB_RESSEL_16BIT
-		default:
-			resolution = sam.ADC_CTRLB_RESSEL_12BIT
-		}
-		adc.CTRLB.SetBits(uint16(resolution << sam.ADC_CTRLB_RESSEL_Pos))
-		adc.SAMPCTRL.Set(5) // sampling Time Length
-
-		for adc.SYNCBUSY.HasBits(sam.ADC_SYNCBUSY_SAMPCTRL) {
-		} // wait for sync
-
-		// No Negative input (Internal Ground)
-		adc.INPUTCTRL.Set(sam.ADC_INPUTCTRL_MUXNEG_GND << sam.ADC_INPUTCTRL_MUXNEG_Pos)
-		for adc.SYNCBUSY.HasBits(sam.ADC_SYNCBUSY_INPUTCTRL) {
-		} // wait for sync
-
-		// Averaging (see datasheet table in AVGCTRL register description)
-		var samples uint32
-		switch config.Samples {
-		case 1:
-			samples = sam.ADC_AVGCTRL_SAMPLENUM_1
-		case 2:
-			samples = sam.ADC_AVGCTRL_SAMPLENUM_2
-		case 4:
-			samples = sam.ADC_AVGCTRL_SAMPLENUM_4
-		case 8:
-			samples = sam.ADC_AVGCTRL_SAMPLENUM_8
-		case 16:
-			samples = sam.ADC_AVGCTRL_SAMPLENUM_16
-		case 32:
-			samples = sam.ADC_AVGCTRL_SAMPLENUM_32
-		case 64:
-			samples = sam.ADC_AVGCTRL_SAMPLENUM_64
-		case 128:
-			samples = sam.ADC_AVGCTRL_SAMPLENUM_128
-		case 256:
-			samples = sam.ADC_AVGCTRL_SAMPLENUM_256
-		case 512:
-			samples = sam.ADC_AVGCTRL_SAMPLENUM_512
-		case 1024:
-			samples = sam.ADC_AVGCTRL_SAMPLENUM_1024
-		default: // 1 sample only (no oversampling nor averaging), adjusting result by 0
-			samples = sam.ADC_AVGCTRL_SAMPLENUM_1
-		}
-		adc.AVGCTRL.Set(uint8(samples<<sam.ADC_AVGCTRL_SAMPLENUM_Pos) |
-			(0 << sam.ADC_AVGCTRL_ADJRES_Pos))
-
-		for adc.SYNCBUSY.HasBits(sam.ADC_SYNCBUSY_AVGCTRL) {
-		} // wait for sync
-		for adc.SYNCBUSY.HasBits(sam.ADC_SYNCBUSY_REFCTRL) {
-		} // wait for sync
-
-		// TODO: use config.Reference to set AREF level
-
-		// default is 3V3 reference voltage
-		adc.REFCTRL.SetBits(sam.ADC_REFCTRL_REFSEL_INTVCC1)
-	}
-
+func (a ADC) Configure() {
 	a.Pin.Configure(PinConfig{Mode: PinAnalog})
 }
 
@@ -1470,96 +1450,6 @@ func (spi SPI) Transfer(w byte) (byte, error) {
 	return byte(spi.Bus.DATA.Get()), nil
 }
 
-var (
-	ErrTxInvalidSliceSize = errors.New("SPI write and read slices must be same size")
-)
-
-// Tx handles read/write operation for SPI interface. Since SPI is a syncronous write/read
-// interface, there must always be the same number of bytes written as bytes read.
-// The Tx method knows about this, and offers a few different ways of calling it.
-//
-// This form sends the bytes in tx buffer, putting the resulting bytes read into the rx buffer.
-// Note that the tx and rx buffers must be the same size:
-//
-// 		spi.Tx(tx, rx)
-//
-// This form sends the tx buffer, ignoring the result. Useful for sending "commands" that return zeros
-// until all the bytes in the command packet have been received:
-//
-// 		spi.Tx(tx, nil)
-//
-// This form sends zeros, putting the result into the rx buffer. Good for reading a "result packet":
-//
-// 		spi.Tx(nil, rx)
-//
-func (spi SPI) Tx(w, r []byte) error {
-	switch {
-	case w == nil:
-		// read only, so write zero and read a result.
-		spi.rx(r)
-	case r == nil:
-		// write only
-		spi.tx(w)
-
-	default:
-		// write/read
-		if len(w) != len(r) {
-			return ErrTxInvalidSliceSize
-		}
-
-		spi.txrx(w, r)
-	}
-
-	return nil
-}
-
-func (spi SPI) tx(tx []byte) {
-	for i := 0; i < len(tx); i++ {
-		for !spi.Bus.INTFLAG.HasBits(sam.SERCOM_SPIM_INTFLAG_DRE) {
-		}
-		spi.Bus.DATA.Set(uint32(tx[i]))
-	}
-	for !spi.Bus.INTFLAG.HasBits(sam.SERCOM_SPIM_INTFLAG_TXC) {
-	}
-
-	// read to clear RXC register
-	for spi.Bus.INTFLAG.HasBits(sam.SERCOM_SPIM_INTFLAG_RXC) {
-		spi.Bus.DATA.Get()
-	}
-}
-
-func (spi SPI) rx(rx []byte) {
-	spi.Bus.DATA.Set(0)
-	for !spi.Bus.INTFLAG.HasBits(sam.SERCOM_SPIM_INTFLAG_DRE) {
-	}
-
-	for i := 1; i < len(rx); i++ {
-		spi.Bus.DATA.Set(0)
-		for !spi.Bus.INTFLAG.HasBits(sam.SERCOM_SPIM_INTFLAG_RXC) {
-		}
-		rx[i-1] = byte(spi.Bus.DATA.Get())
-	}
-	for !spi.Bus.INTFLAG.HasBits(sam.SERCOM_SPIM_INTFLAG_RXC) {
-	}
-	rx[len(rx)-1] = byte(spi.Bus.DATA.Get())
-}
-
-func (spi SPI) txrx(tx, rx []byte) {
-	spi.Bus.DATA.Set(uint32(tx[0]))
-	for !spi.Bus.INTFLAG.HasBits(sam.SERCOM_SPIM_INTFLAG_DRE) {
-	}
-
-	for i := 1; i < len(rx); i++ {
-		spi.Bus.DATA.Set(uint32(tx[i]))
-		for !spi.Bus.INTFLAG.HasBits(sam.SERCOM_SPIM_INTFLAG_RXC) {
-		}
-		rx[i-1] = byte(spi.Bus.DATA.Get())
-	}
-	for !spi.Bus.INTFLAG.HasBits(sam.SERCOM_SPIM_INTFLAG_RXC) {
-	}
-	rx[len(rx)-1] = byte(spi.Bus.DATA.Get())
-}
-
 // The QSPI peripheral on ATSAMD51 is only available on the following pins
 const (
 	QSPI_SCK   = PB10
@@ -1825,104 +1715,36 @@ func (pwm PWM) getMux() PinMode {
 
 // USBCDC is the USB CDC aka serial over USB interface on the SAMD21.
 type USBCDC struct {
-	Buffer            *RingBuffer
-	TxIdx             volatile.Register8
-	waitTxc           bool
-	waitTxcRetryCount uint8
-	sent              bool
-}
-
-const (
-	usbcdcTxSizeMask          uint8 = 0x3F
-	usbcdcTxBankMask          uint8 = ^usbcdcTxSizeMask
-	usbcdcTxBank1st           uint8 = 0x00
-	usbcdcTxBank2nd           uint8 = usbcdcTxSizeMask + 1
-	usbcdcTxMaxRetriesAllowed uint8 = 5
-)
-
-// Flush flushes buffered data.
-func (usbcdc *USBCDC) Flush() error {
-	if usbLineInfo.lineState > 0 {
-		idx := usbcdc.TxIdx.Get()
-		sz := idx & usbcdcTxSizeMask
-		bk := idx & usbcdcTxBankMask
-		if 0 < sz {
-
-			if usbcdc.waitTxc {
-				// waiting for the next flush(), because the transmission is not complete
-				return nil
-			}
-			usbcdc.waitTxc = true
-			usbcdc.waitTxcRetryCount = 0
-
-			// set the data
-			usbEndpointDescriptors[usb_CDC_ENDPOINT_IN].DeviceDescBank[1].ADDR.Set(uint32(uintptr(unsafe.Pointer(&udd_ep_in_cache_buffer[usb_CDC_ENDPOINT_IN][bk]))))
-			if bk == usbcdcTxBank1st {
-				usbcdc.TxIdx.Set(usbcdcTxBank2nd)
-			} else {
-				usbcdc.TxIdx.Set(usbcdcTxBank1st)
-			}
-
-			// clean multi packet size of bytes already sent
-			usbEndpointDescriptors[usb_CDC_ENDPOINT_IN].DeviceDescBank[1].PCKSIZE.ClearBits(usb_DEVICE_PCKSIZE_MULTI_PACKET_SIZE_Mask << usb_DEVICE_PCKSIZE_MULTI_PACKET_SIZE_Pos)
-
-			// set count of bytes to be sent
-			usbEndpointDescriptors[usb_CDC_ENDPOINT_IN].DeviceDescBank[1].PCKSIZE.ClearBits(usb_DEVICE_PCKSIZE_BYTE_COUNT_Mask << usb_DEVICE_PCKSIZE_BYTE_COUNT_Pos)
-			usbEndpointDescriptors[usb_CDC_ENDPOINT_IN].DeviceDescBank[1].PCKSIZE.SetBits((uint32(sz) & usb_DEVICE_PCKSIZE_BYTE_COUNT_Mask) << usb_DEVICE_PCKSIZE_BYTE_COUNT_Pos)
-
-			// clear transfer complete flag
-			setEPINTFLAG(usb_CDC_ENDPOINT_IN, sam.USB_DEVICE_ENDPOINT_EPINTFLAG_TRCPT1)
-
-			// send data by setting bank ready
-			setEPSTATUSSET(usb_CDC_ENDPOINT_IN, sam.USB_DEVICE_ENDPOINT_EPSTATUSSET_BK1RDY)
-			UART0.sent = true
-		}
-	}
-	return nil
+	Buffer *RingBuffer
 }
 
 // WriteByte writes a byte of data to the USB CDC interface.
-func (usbcdc *USBCDC) WriteByte(c byte) error {
+func (usbcdc USBCDC) WriteByte(c byte) error {
 	// Supposedly to handle problem with Windows USB serial ports?
 	if usbLineInfo.lineState > 0 {
-		ok := false
-		for {
-			mask := interrupt.Disable()
+		// set the data
+		udd_ep_in_cache_buffer[usb_CDC_ENDPOINT_IN][0] = c
 
-			idx := UART0.TxIdx.Get()
-			if (idx & usbcdcTxSizeMask) < usbcdcTxSizeMask {
-				udd_ep_in_cache_buffer[usb_CDC_ENDPOINT_IN][idx] = c
-				UART0.TxIdx.Set(idx + 1)
-				ok = true
-			}
+		usbEndpointDescriptors[usb_CDC_ENDPOINT_IN].DeviceDescBank[1].ADDR.Set(uint32(uintptr(unsafe.Pointer(&udd_ep_in_cache_buffer[usb_CDC_ENDPOINT_IN]))))
 
-			interrupt.Restore(mask)
+		// clean multi packet size of bytes already sent
+		usbEndpointDescriptors[usb_CDC_ENDPOINT_IN].DeviceDescBank[1].PCKSIZE.ClearBits(usb_DEVICE_PCKSIZE_MULTI_PACKET_SIZE_Mask << usb_DEVICE_PCKSIZE_MULTI_PACKET_SIZE_Pos)
 
-			if ok {
-				break
-			} else if usbcdcTxMaxRetriesAllowed < UART0.waitTxcRetryCount {
-				mask := interrupt.Disable()
-				UART0.waitTxc = false
-				UART0.waitTxcRetryCount = 0
-				usbcdc.TxIdx.Set(0)
-				usbLineInfo.lineState = 0
-				interrupt.Restore(mask)
-				break
-			} else {
-				mask := interrupt.Disable()
-				if UART0.sent {
-					if UART0.waitTxc {
-						if (getEPINTFLAG(usb_CDC_ENDPOINT_IN) & sam.USB_DEVICE_ENDPOINT_EPINTFLAG_TRCPT1) != 0 {
-							setEPSTATUSCLR(usb_CDC_ENDPOINT_IN, sam.USB_DEVICE_ENDPOINT_EPSTATUSCLR_BK1RDY)
-							setEPINTFLAG(usb_CDC_ENDPOINT_IN, sam.USB_DEVICE_ENDPOINT_EPINTFLAG_TRCPT1)
-							UART0.waitTxc = false
-							UART0.Flush()
-						}
-					} else {
-						UART0.Flush()
-					}
-				}
-				interrupt.Restore(mask)
+		// set count of bytes to be sent
+		usbEndpointDescriptors[usb_CDC_ENDPOINT_IN].DeviceDescBank[1].PCKSIZE.SetBits((1 & usb_DEVICE_PCKSIZE_BYTE_COUNT_Mask) << usb_DEVICE_PCKSIZE_BYTE_COUNT_Pos)
+
+		// clear transfer complete flag
+		setEPINTFLAG(usb_CDC_ENDPOINT_IN, sam.USB_DEVICE_ENDPOINT_EPINTFLAG_TRCPT1)
+
+		// send data by setting bank ready
+		setEPSTATUSSET(usb_CDC_ENDPOINT_IN, sam.USB_DEVICE_ENDPOINT_EPSTATUSSET_BK1RDY)
+
+		// wait for transfer to complete
+		timeout := 3000
+		for (getEPINTFLAG(usb_CDC_ENDPOINT_IN) & sam.USB_DEVICE_ENDPOINT_EPINTFLAG_TRCPT1) == 0 {
+			timeout--
+			if timeout == 0 {
+				return errUSBCDCWriteByteTimeout
 			}
 		}
 	}
@@ -2131,19 +1953,9 @@ func handleUSBIRQ(interrupt.Interrupt) {
 			case usb_CDC_ENDPOINT_IN, usb_CDC_ENDPOINT_ACM:
 				setEPSTATUSCLR(i, sam.USB_DEVICE_ENDPOINT_EPSTATUSCLR_BK1RDY)
 				setEPINTFLAG(i, sam.USB_DEVICE_ENDPOINT_EPINTFLAG_TRCPT1)
-
-				if i == usb_CDC_ENDPOINT_IN {
-					UART0.waitTxc = false
-				}
 			}
 		}
-
-		if i == usb_CDC_ENDPOINT_IN && UART0.waitTxc {
-			UART0.waitTxcRetryCount++
-		}
 	}
-
-	UART0.Flush()
 }
 
 func initEndpoint(ep, config uint32) {

src/machine/machine_atsamd51p20.go

@@ -1,70 +0,0 @@
-// +build sam,atsamd51,atsamd51p20
-
-// Peripheral abstraction layer for the atsamd51.
-//
-// Datasheet:
-// http://ww1.microchip.com/downloads/en/DeviceDoc/60001507C.pdf
-//
-package machine
-
-import "device/sam"
-
-const HSRAM_SIZE = 0x00040000
-
-// InitPWM initializes the PWM interface.
-func InitPWM() {
-	// turn on timer clocks used for PWM
-	sam.MCLK.APBBMASK.SetBits(sam.MCLK_APBBMASK_TCC0_ | sam.MCLK_APBBMASK_TCC1_)
-	sam.MCLK.APBCMASK.SetBits(sam.MCLK_APBCMASK_TCC2_ | sam.MCLK_APBCMASK_TCC3_)
-	sam.MCLK.APBDMASK.SetBits(sam.MCLK_APBDMASK_TCC4_)
-
-	//use clock generator 0
-	sam.GCLK.PCHCTRL[sam.PCHCTRL_GCLK_TCC0].Set((sam.GCLK_PCHCTRL_GEN_GCLK0 << sam.GCLK_PCHCTRL_GEN_Pos) |
-		sam.GCLK_PCHCTRL_CHEN)
-	sam.GCLK.PCHCTRL[sam.PCHCTRL_GCLK_TCC2].Set((sam.GCLK_PCHCTRL_GEN_GCLK0 << sam.GCLK_PCHCTRL_GEN_Pos) |
-		sam.GCLK_PCHCTRL_CHEN)
-	sam.GCLK.PCHCTRL[sam.PCHCTRL_GCLK_TCC4].Set((sam.GCLK_PCHCTRL_GEN_GCLK0 << sam.GCLK_PCHCTRL_GEN_Pos) |
-		sam.GCLK_PCHCTRL_CHEN)
-}
-
-// getTimer returns the timer to be used for PWM on this pin
-func (pwm PWM) getTimer() *sam.TCC_Type {
-	switch pwm.Pin {
-	case PC18:
-		return sam.TCC0
-	case PC19:
-		return sam.TCC0
-	case PC20:
-		return sam.TCC0
-	case PC21:
-		return sam.TCC0
-	case PD20:
-		return sam.TCC1
-	case PD21:
-		return sam.TCC1
-	case PB18:
-		return sam.TCC1
-	case PB12:
-		return sam.TCC3
-	case PB13:
-		return sam.TCC3
-	case PA15:
-		return sam.TCC2
-	case PC17:
-		return sam.TCC0
-	case PC16:
-		return sam.TCC0
-	case PA14:
-		return sam.TCC2
-	case PB15:
-		return sam.TCC4
-	case PB14:
-		return sam.TCC4
-	case PB20:
-		return sam.TCC1
-	case PB21:
-		return sam.TCC1
-	default:
-		return nil // not supported on this pin
-	}
-}

src/machine/machine_attiny.go

@@ -2,6 +2,23 @@
 
 package machine
 
+// UART on the AVR is a dummy implementation. UART has not been implemented for ATtiny
+// devices.
+type UART struct {
+	Buffer *RingBuffer
+}
+
+// Configure is a dummy implementation. UART has not been implemented for ATtiny
+// devices.
+func (uart UART) Configure(config UARTConfig) {
+}
+
+// WriteByte is a dummy implementation. UART has not been implemented for ATtiny
+// devices.
+func (uart UART) WriteByte(c byte) error {
+	return nil
+}
+
 // Tx is a dummy implementation. I2C has not been implemented for ATtiny
 // devices.
 func (i2c I2C) Tx(addr uint16, w, r []byte) error {

src/machine/machine_avr.go

@@ -118,7 +118,7 @@ func InitADC() {
 }
 
 // Configure configures a ADCPin to be able to be used to read data.
-func (a ADC) Configure(ADCConfig) {
+func (a ADC) Configure() {
 	return // no pin specific setup on AVR machine.
 }
 
@@ -148,3 +148,9 @@ type I2C struct {
 
 // I2C0 is the only I2C interface on most AVRs.
 var I2C0 = I2C{}
+
+// UART
+var (
+	// UART0 is the hardware serial port on the AVR.
+	UART0 = UART{Buffer: NewRingBuffer()}
+)

src/machine/machine_fe310.go

@@ -174,13 +174,11 @@ func (spi SPI) Transfer(w byte) (byte, error) {
 	spi.Bus.TXDATA.Set(uint32(w))
 
 	// wait until receive has data
-	data := spi.Bus.RXDATA.Get()
-	for data&sifive.QSPI_RXDATA_EMPTY > 0 {
-		data = spi.Bus.RXDATA.Get()
+	for spi.Bus.RXDATA.HasBits(sifive.QSPI_RXDATA_EMPTY) {
 	}
 
 	// return data
-	return byte(data), nil
+	return byte(spi.Bus.RXDATA.Get() & sifive.QSPI_RXDATA_DATA_Msk), nil
 }
 
 // I2C on the FE310-G002.

src/machine/machine_generic.go

@@ -73,7 +73,7 @@ func InitADC() {
 }
 
 // Configure configures an ADC pin to be able to be used to read data.
-func (adc ADC) Configure(ADCConfig) {
+func (adc ADC) Configure() {
 }
 
 // Get reads the current analog value from this ADC peripheral.
@@ -115,9 +115,8 @@ type I2CConfig struct {
 }
 
 // Configure is intended to setup the I2C interface.
-func (i2c I2C) Configure(config I2CConfig) error {
+func (i2c I2C) Configure(config I2CConfig) {
 	i2cConfigure(i2c.Bus, config.SCL, config.SDA)
-	return nil
 }
 
 // Tx does a single I2C transaction at the specified address.

src/machine/machine_mimxrt1062_uart.go

@@ -15,10 +15,6 @@ type UART struct {
 	Buffer    *RingBuffer
 	Interrupt interrupt.Interrupt
 
-	// txBuffer should be allocated globally (such as when UART is created) to
-	// prevent it being reclaimed or cleaned up prematurely.
-	txBuffer *RingBuffer
-
 	// these hold the input selector ("daisy chain") values that select which pins
 	// are connected to the LPUART device, and should be defined where the UART
 	// instance is declared. see the godoc comments on type muxSelect for more
@@ -35,6 +31,7 @@ type UART struct {
 	configured   bool
 	msbFirst     bool
 	transmitting volatile.Register32
+	txBuffer     *RingBuffer
 }
 
 func (uart *UART) isTransmitting() bool { return uart.transmitting.Get() != 0 }
@@ -200,6 +197,9 @@ func (uart *UART) Sync() error {
 
 // WriteByte writes a single byte of data to the UART interface.
 func (uart *UART) WriteByte(c byte) error {
+	if nil == uart.txBuffer {
+		uart.txBuffer = NewRingBuffer()
+	}
 	uart.startTransmitting()
 	for !uart.txBuffer.Put(c) {
 	}

src/machine/machine_nrf.go

@@ -220,7 +220,7 @@ type I2CConfig struct {
 }
 
 // Configure is intended to setup the I2C interface.
-func (i2c I2C) Configure(config I2CConfig) error {
+func (i2c I2C) Configure(config I2CConfig) {
 	// Default I2C bus speed is 100 kHz.
 	if config.Frequency == 0 {
 		config.Frequency = TWI_FREQ_100KHZ
@@ -254,8 +254,6 @@ func (i2c I2C) Configure(config I2CConfig) error {
 
 	i2c.Bus.ENABLE.Set(nrf.TWI_ENABLE_ENABLE_Enabled)
 	i2c.setPins(config.SCL, config.SDA)
-
-	return nil
 }
 
 // Tx does a single I2C transaction at the specified address.

src/machine/machine_nrf528xx.go

@@ -17,7 +17,7 @@ func InitADC() {
 }
 
 // Configure configures an ADC pin to be able to read analog data.
-func (a ADC) Configure(ADCConfig) {
+func (a ADC) Configure() {
 	return // no pin specific setup on nrf52 machine.
 }
 

src/machine/machine_stm32_f7_uart.go

@@ -0,0 +1,62 @@
+// +build stm32f7
+
+package machine
+
+// Peripheral abstraction layer for UARTs on the stm32 family.
+
+import (
+	"device/stm32"
+	"runtime/interrupt"
+	"unsafe"
+)
+
+// Configure the UART.
+func (uart UART) Configure(config UARTConfig) {
+	// Default baud rate to 115200.
+	if config.BaudRate == 0 {
+		config.BaudRate = 115200
+	}
+
+	// Set the GPIO pins to defaults if they're not set
+	if config.TX == 0 && config.RX == 0 {
+		config.TX = UART_TX_PIN
+		config.RX = UART_RX_PIN
+	}
+
+	// Enable USART clock
+	enableAltFuncClock(unsafe.Pointer(uart.Bus))
+
+	uart.configurePins(config)
+
+	// Set baud rate
+	uart.SetBaudRate(config.BaudRate)
+
+	// Enable USART port, tx, rx and rx interrupts
+	uart.Bus.CR1.Set(stm32.USART_CR1_TE | stm32.USART_CR1_RE | stm32.USART_CR1_RXNEIE | stm32.USART_CR1_UE)
+
+	// Enable RX IRQ
+	uart.Interrupt.SetPriority(0xc0)
+	uart.Interrupt.Enable()
+}
+
+// handleInterrupt should be called from the appropriate interrupt handler for
+// this UART instance.
+func (uart *UART) handleInterrupt(interrupt.Interrupt) {
+	uart.Receive(byte((uart.Bus.RDR.Get() & 0xFF)))
+}
+
+// SetBaudRate sets the communication speed for the UART. Defer to chip-specific
+// routines for calculation
+func (uart UART) SetBaudRate(br uint32) {
+	divider := uart.getBaudRateDivisor(br)
+	uart.Bus.BRR.Set(divider)
+}
+
+// WriteByte writes a byte of data to the UART.
+func (uart UART) WriteByte(c byte) error {
+	uart.Bus.TDR.Set(uint32(c))
+
+	for !uart.Bus.ISR.HasBits(stm32.USART_ISR_TXE) {
+	}
+	return nil
+}

src/machine/machine_stm32_i2c.go

@@ -1,4 +1,4 @@
-// +build stm32,!stm32f7x2,!stm32l5x2,!stm32l0
+// +build stm32,!stm32f103,!stm32f407,!stm32f7x2,!stm32l0
 
 package machine
 
@@ -91,6 +91,42 @@ const (
 	frameNoOption     = 0xFFFF0000
 )
 
+// addressable represents a type that can provide fully-formatted I2C peripheral
+// addresses for both read operations and write operations.
+type addressable interface {
+	toRead() uint32
+	toWrite() uint32
+	bitSize() uint8
+}
+
+// address7Bit and address10Bit stores the unshifted original I2C peripheral address
+// in an unsigned integral data type and implements the addressable interface
+// to reformat addresses as required for read/write operations.
+//   TODO:
+//    add 10-bit address support
+type (
+	address7Bit uint8
+	//address10Bit uint16
+)
+
+func (sa address7Bit) toRead() uint32 {
+	return uint32(((uint8(sa) << 1) | 1) & 0xFF)
+}
+func (sa address7Bit) toWrite() uint32 {
+	return uint32((uint8(sa) << 1) & 0xFF)
+}
+func (sa address7Bit) bitSize() uint8 { return 7 } // 7-bit addresses
+
+//func (sa address10Bit) toRead() uint32  {}
+//func (sa address10Bit) toWrite() uint32 {}
+//func (sa address10Bit) bitSize() uint8  { return 10 } // 10-bit addresses
+
+func readAddress7Bit(addr uint8) uint32  { return address7Bit(addr).toRead() }
+func writeAddress7Bit(addr uint8) uint32 { return address7Bit(addr).toWrite() }
+
+//func readAddress10Bit(addr uint16) uint32  { return address10Bit(addr).toRead() }
+//func writeAddress10Bit(addr uint16) uint32 { return address10Bit(addr).toWrite() }
+
 // I2C fast mode (Fm) duty cycle
 const (
 	DutyCycle2    = 0
@@ -106,7 +142,7 @@ type I2CConfig struct {
 }
 
 // Configure is intended to setup the STM32 I2C interface.
-func (i2c I2C) Configure(config I2CConfig) error {
+func (i2c I2C) Configure(config I2CConfig) {
 
 	// The following is the required sequence in controller mode.
 	// 1. Program the peripheral input clock in I2C_CR2 Register in order to
@@ -151,32 +187,31 @@ func (i2c I2C) Configure(config I2CConfig) error {
 	i2c.Bus.CR1.ClearBits(stm32.I2C_CR1_ENGC | stm32.I2C_CR1_NOSTRETCH)
 
 	// enable I2C interface
-	i2c.Bus.CR1.SetBits(stm32.I2C_CR1_PE)
-
-	return nil
+	i2c.Bus.CR1.ClearBits(stm32.I2C_CR1_PE)
 }
 
 func (i2c I2C) Tx(addr uint16, w, r []byte) error {
-
-	if err := i2c.controllerTransmit(addr, w); nil != err {
+	a := address7Bit(addr)
+	if err := i2c.controllerTransmit(a, w); nil != err {
 		return err
 	}
-
-	if len(r) > 0 {
-		if err := i2c.controllerReceive(addr, r); nil != err {
-			return err
-		}
+	if err := i2c.controllerReceive(a, r); nil != err {
+		return err
 	}
-
 	return nil
 }
 
-func (i2c I2C) controllerTransmit(addr uint16, w []byte) error {
+func (i2c I2C) controllerTransmit(addr addressable, w []byte) error {
 
 	if !i2c.waitForFlag(flagBUSY, false) {
 		return errI2CBusReadyTimeout
 	}
 
+	// ensure peripheral is enabled
+	if !i2c.Bus.CR1.HasBits(stm32.I2C_CR1_PE) {
+		i2c.Bus.CR1.SetBits(stm32.I2C_CR1_PE)
+	}
+
 	// disable POS
 	i2c.Bus.CR1.ClearBits(stm32.I2C_CR1_POS)
 
@@ -223,7 +258,7 @@ func (i2c I2C) controllerTransmit(addr uint16, w []byte) error {
 	return nil
 }
 
-func (i2c I2C) controllerRequestWrite(addr uint16, option transferOption) error {
+func (i2c I2C) controllerRequestWrite(addr addressable, option transferOption) error {
 
 	if frameFirstAndLast == option || frameFirst == option || frameNoOption == option {
 		// generate start condition
@@ -239,7 +274,13 @@ func (i2c I2C) controllerRequestWrite(addr uint16, option transferOption) error
 	}
 
 	// send peripheral address
-	i2c.Bus.DR.Set(uint32(addr) << 1)
+	switch addr.bitSize() {
+	case 7: // 7-bit peripheral address
+		i2c.Bus.DR.Set(addr.toWrite())
+
+	case 10: // 10-bit peripheral address
+		// TODO
+	}
 
 	// wait for address ACK from peripheral
 	if !i2c.waitForFlagOrError(flagADDR, true) {
@@ -249,12 +290,17 @@ func (i2c I2C) controllerRequestWrite(addr uint16, option transferOption) error
 	return nil
 }
 
-func (i2c I2C) controllerReceive(addr uint16, r []byte) error {
+func (i2c I2C) controllerReceive(addr addressable, r []byte) error {
 
 	if !i2c.waitForFlag(flagBUSY, false) {
 		return errI2CBusReadyTimeout
 	}
 
+	// ensure peripheral is enabled
+	if !i2c.Bus.CR1.HasBits(stm32.I2C_CR1_PE) {
+		i2c.Bus.CR1.SetBits(stm32.I2C_CR1_PE)
+	}
+
 	// disable POS
 	i2c.Bus.CR1.ClearBits(stm32.I2C_CR1_POS)
 
@@ -399,7 +445,7 @@ func (i2c I2C) controllerReceive(addr uint16, r []byte) error {
 	return nil
 }
 
-func (i2c I2C) controllerRequestRead(addr uint16, option transferOption) error {
+func (i2c I2C) controllerRequestRead(addr addressable, option transferOption) error {
 
 	// enable ACK
 	i2c.Bus.CR1.SetBits(stm32.I2C_CR1_ACK)
@@ -418,7 +464,13 @@ func (i2c I2C) controllerRequestRead(addr uint16, option transferOption) error {
 	}
 
 	// send peripheral address
-	i2c.Bus.DR.Set(uint32(addr)<<1 | 1)
+	switch addr.bitSize() {
+	case 7: // 7-bit peripheral address
+		i2c.Bus.DR.Set(addr.toRead())
+
+	case 10: // 10-bit peripheral address
+		// TODO
+	}
 
 	// wait for address ACK from peripheral
 	if !i2c.waitForFlagOrError(flagADDR, true) {

src/machine/machine_stm32_spi.go

@@ -1,4 +1,4 @@
-// +build stm32,!stm32f7x2,!stm32l5x2
+// +build stm32,!stm32f7x2
 
 package machine
 

src/machine/machine_stm32_uart.go

@@ -1,4 +1,4 @@
-// +build stm32
+// +build stm32,!stm32f7,!stm32l0
 
 package machine
 
@@ -7,26 +7,11 @@ package machine
 import (
 	"device/stm32"
 	"runtime/interrupt"
-	"runtime/volatile"
 	"unsafe"
 )
 
-// UART representation
-type UART struct {
-	Buffer          *RingBuffer
-	Bus             *stm32.USART_Type
-	Interrupt       interrupt.Interrupt
-	AltFuncSelector uint8
-
-	// Registers specific to the chip
-	rxReg       *volatile.Register32
-	txReg       *volatile.Register32
-	statusReg   *volatile.Register32
-	txEmptyFlag uint32
-}
-
 // Configure the UART.
-func (uart *UART) Configure(config UARTConfig) {
+func (uart UART) Configure(config UARTConfig) {
 	// Default baud rate to 115200.
 	if config.BaudRate == 0 {
 		config.BaudRate = 115200
@@ -38,11 +23,6 @@ func (uart *UART) Configure(config UARTConfig) {
 		config.RX = UART_RX_PIN
 	}
 
-	// STM32 families have different, but compatible, registers for
-	// basic UART functions.  For each family populate the registers
-	// into `uart`.
-	uart.setRegisters()
-
 	// Enable USART clock
 	enableAltFuncClock(unsafe.Pointer(uart.Bus))
 
@@ -62,21 +42,21 @@ func (uart *UART) Configure(config UARTConfig) {
 // handleInterrupt should be called from the appropriate interrupt handler for
 // this UART instance.
 func (uart *UART) handleInterrupt(interrupt.Interrupt) {
-	uart.Receive(byte((uart.rxReg.Get() & 0xFF)))
+	uart.Receive(byte((uart.Bus.DR.Get() & 0xFF)))
 }
 
 // SetBaudRate sets the communication speed for the UART. Defer to chip-specific
 // routines for calculation
-func (uart *UART) SetBaudRate(br uint32) {
+func (uart UART) SetBaudRate(br uint32) {
 	divider := uart.getBaudRateDivisor(br)
 	uart.Bus.BRR.Set(divider)
 }
 
 // WriteByte writes a byte of data to the UART.
-func (uart *UART) WriteByte(c byte) error {
-	uart.txReg.Set(uint32(c))
+func (uart UART) WriteByte(c byte) error {
+	uart.Bus.DR.Set(uint32(c))
 
-	for !uart.statusReg.HasBits(uart.txEmptyFlag) {
+	for !uart.Bus.SR.HasBits(stm32.USART_SR_TXE) {
 	}
 	return nil
 }

src/machine/machine_stm32f103.go

@@ -6,6 +6,7 @@ package machine
 
 import (
 	"device/stm32"
+	"runtime/interrupt"
 	"unsafe"
 )
 
@@ -102,10 +103,17 @@ func enableAltFuncClock(bus unsafe.Pointer) {
 	}
 }
 
-//---------- UART related code
+//---------- UART related types and code
+
+// UART representation
+type UART struct {
+	Buffer    *RingBuffer
+	Bus       *stm32.USART_Type
+	Interrupt interrupt.Interrupt
+}
 
 // Configure the TX and RX pins
-func (uart *UART) configurePins(config UARTConfig) {
+func (uart UART) configurePins(config UARTConfig) {
 
 	// pins
 	switch config.TX {
@@ -125,7 +133,7 @@ func (uart *UART) configurePins(config UARTConfig) {
 }
 
 // Determine the divisor for USARTs to get the given baudrate
-func (uart *UART) getBaudRateDivisor(br uint32) uint32 {
+func (uart UART) getBaudRateDivisor(br uint32) uint32 {
 
 	// Note: PCLK2 (from APB2) used for USART1 and PCLK1 for USART2, 3, 4, 5
 	var divider uint32
@@ -139,14 +147,6 @@ func (uart *UART) getBaudRateDivisor(br uint32) uint32 {
 	return divider
 }
 
-// Register names vary by ST processor, these are for STM F103xx
-func (uart *UART) setRegisters() {
-	uart.rxReg = &uart.Bus.DR
-	uart.txReg = &uart.Bus.DR
-	uart.statusReg = &uart.Bus.SR
-	uart.txEmptyFlag = stm32.USART_SR_TXE
-}
-
 //---------- SPI related types and code
 
 type SPI struct {
@@ -197,6 +197,10 @@ func (spi SPI) configurePins(config SPIConfig) {
 
 //---------- I2C related types and code
 
+type I2C struct {
+	Bus *stm32.I2C_Type
+}
+
 // There are 2 I2C interfaces on the STM32F103xx.
 // Since the first interface is named I2C1, both I2C0 and I2C1 refer to I2C1.
 // TODO: implement I2C2.
@@ -205,73 +209,449 @@ var (
 	I2C0 = I2C1
 )
 
-type I2C struct {
-	Bus *stm32.I2C_Type
+// I2CConfig is used to store config info for I2C.
+type I2CConfig struct {
+	Frequency uint32
+	SCL       Pin
+	SDA       Pin
 }
 
-func (i2c I2C) configurePins(config I2CConfig) {
-	if config.SDA == PB9 {
+// Configure is intended to setup the I2C interface.
+func (i2c I2C) Configure(config I2CConfig) {
+	// Default I2C bus speed is 100 kHz.
+	if config.Frequency == 0 {
+		config.Frequency = TWI_FREQ_100KHZ
+	}
+
+	// enable clock for I2C
+	stm32.RCC.APB1ENR.SetBits(stm32.RCC_APB1ENR_I2C1EN)
+
+	// I2C1 pins
+	switch config.SDA {
+	case PB9:
+		config.SCL = PB8
 		// use alternate I2C1 pins PB8/PB9 via AFIO mapping
 		stm32.RCC.APB2ENR.SetBits(stm32.RCC_APB2ENR_AFIOEN)
 		stm32.AFIO.MAPR.SetBits(stm32.AFIO_MAPR_I2C1_REMAP)
+	default:
+		// use default I2C1 pins PB6/PB7
+		config.SDA = SDA_PIN
+		config.SCL = SCL_PIN
 	}
 
 	config.SDA.Configure(PinConfig{Mode: PinOutput50MHz + PinOutputModeAltOpenDrain})
 	config.SCL.Configure(PinConfig{Mode: PinOutput50MHz + PinOutputModeAltOpenDrain})
-}
 
-func (i2c I2C) getFreqRange(config I2CConfig) uint32 {
+	// Disable the selected I2C peripheral to configure
+	i2c.Bus.CR1.ClearBits(stm32.I2C_CR1_PE)
+
 	// pclk1 clock speed is main frequency divided by PCLK1 prescaler (div 2)
 	pclk1 := CPUFrequency() / 2
 
 	// set freqency range to PCLK1 clock speed in MHz
 	// aka setting the value 36 means to use 36 MHz clock
-	return pclk1 / 1000000
+	pclk1Mhz := pclk1 / 1000000
+	i2c.Bus.CR2.SetBits(pclk1Mhz)
+
+	switch config.Frequency {
+	case TWI_FREQ_100KHZ:
+		// Normal mode speed calculation
+		ccr := pclk1 / (config.Frequency * 2)
+		i2c.Bus.CCR.Set(ccr)
+
+		// duty cycle 2
+		i2c.Bus.CCR.ClearBits(stm32.I2C_CCR_DUTY)
+
+		// frequency standard mode
+		i2c.Bus.CCR.ClearBits(stm32.I2C_CCR_F_S)
+
+		// Set Maximum Rise Time for standard mode
+		i2c.Bus.TRISE.Set(pclk1Mhz)
+
+	case TWI_FREQ_400KHZ:
+		// Fast mode speed calculation
+		ccr := pclk1 / (config.Frequency * 3)
+		i2c.Bus.CCR.Set(ccr)
+
+		// duty cycle 2
+		i2c.Bus.CCR.ClearBits(stm32.I2C_CCR_DUTY)
+
+		// frequency fast mode
+		i2c.Bus.CCR.SetBits(stm32.I2C_CCR_F_S)
+
+		// Set Maximum Rise Time for fast mode
+		i2c.Bus.TRISE.Set(((pclk1Mhz * 300) / 1000))
+	}
+
+	// re-enable the selected I2C peripheral
+	i2c.Bus.CR1.SetBits(stm32.I2C_CR1_PE)
 }
 
-func (i2c I2C) getRiseTime(config I2CConfig) uint32 {
-	// These bits must be programmed with the maximum SCL rise time given in the
-	// I2C bus specification, incremented by 1.
-	// For instance: in Sm mode, the maximum allowed SCL rise time is 1000 ns.
-	// If, in the I2C_CR2 register, the value of FREQ[5:0] bits is equal to 0x08
-	// and PCLK1 = 125 ns, therefore the TRISE[5:0] bits must be programmed with
-	// 09h (1000 ns / 125 ns = 8 + 1)
-	freqRange := i2c.getFreqRange(config)
-	if config.Frequency > 100000 {
-		// fast mode (Fm) adjustment
-		freqRange *= 300
-		freqRange /= 1000
+// Tx does a single I2C transaction at the specified address.
+// It clocks out the given address, writes the bytes in w, reads back len(r)
+// bytes and stores them in r, and generates a stop condition on the bus.
+func (i2c I2C) Tx(addr uint16, w, r []byte) error {
+	var err error
+	if len(w) != 0 {
+		// start transmission for writing
+		err = i2c.signalStart()
+		if err != nil {
+			return err
+		}
+
+		// send address
+		err = i2c.sendAddress(uint8(addr), true)
+		if err != nil {
+			return err
+		}
+
+		for _, b := range w {
+			err = i2c.WriteByte(b)
+			if err != nil {
+				return err
+			}
+		}
+
+		// sending stop here for write
+		err = i2c.signalStop()
+		if err != nil {
+			return err
+		}
 	}
-	return (freqRange + 1) << stm32.I2C_TRISE_TRISE_Pos
+	if len(r) != 0 {
+		// re-start transmission for reading
+		err = i2c.signalStart()
+		if err != nil {
+			return err
+		}
+
+		// 1 byte
+		switch len(r) {
+		case 1:
+			// send address
+			err = i2c.sendAddress(uint8(addr), false)
+			if err != nil {
+				return err
+			}
+
+			// Disable ACK of received data
+			i2c.Bus.CR1.ClearBits(stm32.I2C_CR1_ACK)
+
+			// clear timeout here
+			timeout := i2cTimeout
+			for !i2c.Bus.SR2.HasBits(stm32.I2C_SR2_MSL | stm32.I2C_SR2_BUSY) {
+				timeout--
+				if timeout == 0 {
+					return errI2CWriteTimeout
+				}
+			}
+
+			// Generate stop condition
+			i2c.Bus.CR1.SetBits(stm32.I2C_CR1_STOP)
+
+			timeout = i2cTimeout
+			for !i2c.Bus.SR1.HasBits(stm32.I2C_SR1_RxNE) {
+				timeout--
+				if timeout == 0 {
+					return errI2CReadTimeout
+				}
+			}
+
+			// Read and return data byte from I2C data register
+			r[0] = byte(i2c.Bus.DR.Get())
+
+			// wait for stop
+			return i2c.waitForStop()
+
+		case 2:
+			// enable pos
+			i2c.Bus.CR1.SetBits(stm32.I2C_CR1_POS)
+
+			// Enable ACK of received data
+			i2c.Bus.CR1.SetBits(stm32.I2C_CR1_ACK)
+
+			// send address
+			err = i2c.sendAddress(uint8(addr), false)
+			if err != nil {
+				return err
+			}
+
+			// clear address here
+			timeout := i2cTimeout
+			for !i2c.Bus.SR2.HasBits(stm32.I2C_SR2_MSL | stm32.I2C_SR2_BUSY) {
+				timeout--
+				if timeout == 0 {
+					return errI2CWriteTimeout
+				}
+			}
+
+			// Disable ACK of received data
+			i2c.Bus.CR1.ClearBits(stm32.I2C_CR1_ACK)
+
+			// wait for btf. we need a longer timeout here than normal.
+			timeout = 1000
+			for !i2c.Bus.SR1.HasBits(stm32.I2C_SR1_BTF) {
+				timeout--
+				if timeout == 0 {
+					return errI2CReadTimeout
+				}
+			}
+
+			// Generate stop condition
+			i2c.Bus.CR1.SetBits(stm32.I2C_CR1_STOP)
+
+			// read the 2 bytes by reading twice.
+			r[0] = byte(i2c.Bus.DR.Get())
+			r[1] = byte(i2c.Bus.DR.Get())
+
+			// wait for stop
+			err = i2c.waitForStop()
+
+			//disable pos
+			i2c.Bus.CR1.ClearBits(stm32.I2C_CR1_POS)
+
+			return err
+
+		case 3:
+			// Enable ACK of received data
+			i2c.Bus.CR1.SetBits(stm32.I2C_CR1_ACK)
+
+			// send address
+			err = i2c.sendAddress(uint8(addr), false)
+			if err != nil {
+				return err
+			}
+
+			// clear address here
+			timeout := i2cTimeout
+			for !i2c.Bus.SR2.HasBits(stm32.I2C_SR2_MSL | stm32.I2C_SR2_BUSY) {
+				timeout--
+				if timeout == 0 {
+					return errI2CWriteTimeout
+				}
+			}
+
+			// Enable ACK of received data
+			i2c.Bus.CR1.SetBits(stm32.I2C_CR1_ACK)
+
+			// wait for btf. we need a longer timeout here than normal.
+			timeout = 1000
+			for !i2c.Bus.SR1.HasBits(stm32.I2C_SR1_BTF) {
+				timeout--
+				if timeout == 0 {
+					return errI2CReadTimeout
+				}
+			}
+
+			// Disable ACK of received data
+			i2c.Bus.CR1.ClearBits(stm32.I2C_CR1_ACK)
+
+			// read the first byte
+			r[0] = byte(i2c.Bus.DR.Get())
+
+			timeout = 1000
+			for !i2c.Bus.SR1.HasBits(stm32.I2C_SR1_BTF) {
+				timeout--
+				if timeout == 0 {
+					return errI2CReadTimeout
+				}
+			}
+
+			// Generate stop condition
+			i2c.Bus.CR1.SetBits(stm32.I2C_CR1_STOP)
+
+			// read the last 2 bytes by reading twice.
+			r[1] = byte(i2c.Bus.DR.Get())
+			r[2] = byte(i2c.Bus.DR.Get())
+
+			// wait for stop
+			return i2c.waitForStop()
+
+		default:
+			// more than 3 bytes of data to read
+
+			// send address
+			err = i2c.sendAddress(uint8(addr), false)
+			if err != nil {
+				return err
+			}
+
+			// clear address here
+			timeout := i2cTimeout
+			for !i2c.Bus.SR2.HasBits(stm32.I2C_SR2_MSL | stm32.I2C_SR2_BUSY) {
+				timeout--
+				if timeout == 0 {
+					return errI2CWriteTimeout
+				}
+			}
+
+			for i := 0; i < len(r)-3; i++ {
+				// Enable ACK of received data
+				i2c.Bus.CR1.SetBits(stm32.I2C_CR1_ACK)
+
+				// wait for btf. we need a longer timeout here than normal.
+				timeout = 1000
+				for !i2c.Bus.SR1.HasBits(stm32.I2C_SR1_BTF) {
+					timeout--
+					if timeout == 0 {
+						return errI2CReadTimeout
+					}
+				}
+
+				// read the next byte
+				r[i] = byte(i2c.Bus.DR.Get())
+			}
+
+			// wait for btf. we need a longer timeout here than normal.
+			timeout = 1000
+			for !i2c.Bus.SR1.HasBits(stm32.I2C_SR1_BTF) {
+				timeout--
+				if timeout == 0 {
+					return errI2CReadTimeout
+				}
+			}
+
+			// Disable ACK of received data
+			i2c.Bus.CR1.ClearBits(stm32.I2C_CR1_ACK)
+
+			// get third from last byte
+			r[len(r)-3] = byte(i2c.Bus.DR.Get())
+
+			// Generate stop condition
+			i2c.Bus.CR1.SetBits(stm32.I2C_CR1_STOP)
+
+			// get second from last byte
+			r[len(r)-2] = byte(i2c.Bus.DR.Get())
+
+			timeout = i2cTimeout
+			for !i2c.Bus.SR1.HasBits(stm32.I2C_SR1_RxNE) {
+				timeout--
+				if timeout == 0 {
+					return errI2CReadTimeout
+				}
+			}
+
+			// get last byte
+			r[len(r)-1] = byte(i2c.Bus.DR.Get())
+
+			// wait for stop
+			return i2c.waitForStop()
+		}
+	}
+
+	return nil
 }
 
-func (i2c I2C) getSpeed(config I2CConfig) uint32 {
-	ccr := func(pclk uint32, freq uint32, coeff uint32) uint32 {
-		return (((pclk - 1) / (freq * coeff)) + 1) & stm32.I2C_CCR_CCR_Msk
-	}
-	sm := func(pclk uint32, freq uint32) uint32 { // standard mode (Sm)
-		if s := ccr(pclk, freq, 2); s < 4 {
-			return 4
-		} else {
-			return s
+const i2cTimeout = 1000
+
+// signalStart sends a start signal.
+func (i2c I2C) signalStart() error {
+	// Wait until I2C is not busy
+	timeout := i2cTimeout
+	for i2c.Bus.SR2.HasBits(stm32.I2C_SR2_BUSY) {
+		timeout--
+		if timeout == 0 {
+			return errI2CSignalStartTimeout
 		}
 	}
-	fm := func(pclk uint32, freq uint32, duty uint8) uint32 { // fast mode (Fm)
-		if duty == DutyCycle2 {
-			return ccr(pclk, freq, 3)
-		} else {
-			return ccr(pclk, freq, 25) | stm32.I2C_CCR_DUTY
+
+	// clear stop
+	i2c.Bus.CR1.ClearBits(stm32.I2C_CR1_STOP)
+
+	// Generate start condition
+	i2c.Bus.CR1.SetBits(stm32.I2C_CR1_START)
+
+	// Wait for I2C EV5 aka SB flag.
+	timeout = i2cTimeout
+	for !i2c.Bus.SR1.HasBits(stm32.I2C_SR1_SB) {
+		timeout--
+		if timeout == 0 {
+			return errI2CSignalStartTimeout
 		}
 	}
-	clock := CPUFrequency() / 2
-	if config.Frequency <= 100000 {
-		return sm(clock, config.Frequency)
+
+	return nil
+}
+
+// signalStop sends a stop signal and waits for it to succeed.
+func (i2c I2C) signalStop() error {
+	// Generate stop condition
+	i2c.Bus.CR1.SetBits(stm32.I2C_CR1_STOP)
+
+	// wait for stop
+	return i2c.waitForStop()
+}
+
+// waitForStop waits after a stop signal.
+func (i2c I2C) waitForStop() error {
+	// Wait until I2C is stopped
+	timeout := i2cTimeout
+	for i2c.Bus.SR1.HasBits(stm32.I2C_SR1_STOPF) {
+		timeout--
+		if timeout == 0 {
+			return errI2CSignalStopTimeout
+		}
+	}
+
+	return nil
+}
+
+// Send address of device we want to talk to
+func (i2c I2C) sendAddress(address uint8, write bool) error {
+	data := (address << 1)
+	if !write {
+		data |= 1 // set read flag
+	}
+
+	i2c.Bus.DR.Set(uint32(data))
+
+	// Wait for I2C EV6 event.
+	// Destination device acknowledges address
+	timeout := i2cTimeout
+	if write {
+		// EV6 which is ADDR flag.
+		for !i2c.Bus.SR1.HasBits(stm32.I2C_SR1_ADDR) {
+			timeout--
+			if timeout == 0 {
+				return errI2CWriteTimeout
+			}
+		}
+
+		timeout = i2cTimeout
+		for !i2c.Bus.SR2.HasBits(stm32.I2C_SR2_MSL | stm32.I2C_SR2_BUSY | stm32.I2C_SR2_TRA) {
+			timeout--
+			if timeout == 0 {
+				return errI2CWriteTimeout
+			}
+		}
 	} else {
-		s := fm(clock, config.Frequency, config.DutyCycle)
-		if (s & stm32.I2C_CCR_CCR_Msk) == 0 {
-			return 1
-		} else {
-			return s | stm32.I2C_CCR_F_S
+		// I2C_EVENT_MASTER_RECEIVER_MODE_SELECTED which is ADDR flag.
+		for !i2c.Bus.SR1.HasBits(stm32.I2C_SR1_ADDR) {
+			timeout--
+			if timeout == 0 {
+				return errI2CWriteTimeout
+			}
 		}
 	}
+
+	return nil
+}
+
+// WriteByte writes a single byte to the I2C bus.
+func (i2c I2C) WriteByte(data byte) error {
+	// Send data byte
+	i2c.Bus.DR.Set(uint32(data))
+
+	// Wait for I2C EV8_2 when data has been physically shifted out and
+	// output on the bus.
+	// I2C_EVENT_MASTER_BYTE_TRANSMITTED is TXE flag.
+	timeout := i2cTimeout
+	for !i2c.Bus.SR1.HasBits(stm32.I2C_SR1_TxE) {
+		timeout--
+		if timeout == 0 {
+			return errI2CWriteTimeout
+		}
+	}
+
+	return nil
 }

src/machine/machine_stm32f405.go

@@ -7,6 +7,7 @@ package machine
 import (
 	"device/stm32"
 	"math/bits"
+	"runtime/interrupt"
 )
 
 func CPUFrequency() uint32 {
@@ -35,13 +36,20 @@ const (
 
 // -- UART ---------------------------------------------------------------------
 
-func (uart *UART) configurePins(config UARTConfig) {
+type UART struct {
+	Buffer          *RingBuffer
+	Bus             *stm32.USART_Type
+	Interrupt       interrupt.Interrupt
+	AltFuncSelector uint8
+}
+
+func (uart UART) configurePins(config UARTConfig) {
 	// enable the alternate functions on the TX and RX pins
 	config.TX.ConfigureAltFunc(PinConfig{Mode: PinModeUARTTX}, uart.AltFuncSelector)
 	config.RX.ConfigureAltFunc(PinConfig{Mode: PinModeUARTRX}, uart.AltFuncSelector)
 }
 
-func (uart *UART) getBaudRateDivisor(baudRate uint32) uint32 {
+func (uart UART) getBaudRateDivisor(baudRate uint32) uint32 {
 	var clock uint32
 	switch uart.Bus {
 	case stm32.USART1, stm32.USART6:
@@ -52,14 +60,6 @@ func (uart *UART) getBaudRateDivisor(baudRate uint32) uint32 {
 	return clock / baudRate
 }
 
-// Register names vary by ST processor, these are for STM F405
-func (uart *UART) setRegisters() {
-	uart.rxReg = &uart.Bus.DR
-	uart.txReg = &uart.Bus.DR
-	uart.statusReg = &uart.Bus.SR
-	uart.txEmptyFlag = stm32.USART_SR_TXE
-}
-
 // -- SPI ----------------------------------------------------------------------
 
 type SPI struct {

src/machine/machine_stm32f407.go

@@ -6,6 +6,7 @@ package machine
 
 import (
 	"device/stm32"
+	"runtime/interrupt"
 )
 
 func CPUFrequency() uint32 {
@@ -32,10 +33,18 @@ const (
 	AF15_EVENTOUT             = 15
 )
 
-//---------- UART related code
+//---------- UART related types and code
+
+// UART representation
+type UART struct {
+	Buffer          *RingBuffer
+	Bus             *stm32.USART_Type
+	Interrupt       interrupt.Interrupt
+	AltFuncSelector uint8
+}
 
 // Configure the UART.
-func (uart *UART) configurePins(config UARTConfig) {
+func (uart UART) configurePins(config UARTConfig) {
 	// enable the alternate functions on the TX and RX pins
 	config.TX.ConfigureAltFunc(PinConfig{Mode: PinModeUARTTX}, uart.AltFuncSelector)
 	config.RX.ConfigureAltFunc(PinConfig{Mode: PinModeUARTRX}, uart.AltFuncSelector)
@@ -43,7 +52,7 @@ func (uart *UART) configurePins(config UARTConfig) {
 
 // UART baudrate calc based on the bus and clockspeed
 // NOTE: keep this in sync with the runtime/runtime_stm32f407.go clock init code
-func (uart *UART) getBaudRateDivisor(baudRate uint32) uint32 {
+func (uart UART) getBaudRateDivisor(baudRate uint32) uint32 {
 	var clock uint32
 	switch uart.Bus {
 	case stm32.USART1, stm32.USART6:
@@ -54,14 +63,6 @@ func (uart *UART) getBaudRateDivisor(baudRate uint32) uint32 {
 	return clock / baudRate
 }
 
-// Register names vary by ST processor, these are for STM F407
-func (uart *UART) setRegisters() {
-	uart.rxReg = &uart.Bus.DR
-	uart.txReg = &uart.Bus.DR
-	uart.statusReg = &uart.Bus.SR
-	uart.txEmptyFlag = stm32.USART_SR_TXE
-}
-
 //---------- SPI related types and code
 
 // SPI on the STM32Fxxx using MODER / alternate function pins
@@ -120,81 +121,3 @@ func (spi SPI) configurePins(config SPIConfig) {
 	config.SDO.ConfigureAltFunc(PinConfig{Mode: PinModeSPISDO}, spi.AltFuncSelector)
 	config.SDI.ConfigureAltFunc(PinConfig{Mode: PinModeSPISDI}, spi.AltFuncSelector)
 }
-
-// -- I2C ----------------------------------------------------------------------
-
-type I2C struct {
-	Bus             *stm32.I2C_Type
-	AltFuncSelector uint8
-}
-
-func (i2c I2C) configurePins(config I2CConfig) {
-	config.SCL.ConfigureAltFunc(PinConfig{Mode: PinModeI2CSCL}, i2c.AltFuncSelector)
-	config.SDA.ConfigureAltFunc(PinConfig{Mode: PinModeI2CSDA}, i2c.AltFuncSelector)
-}
-
-func (i2c I2C) getFreqRange(config I2CConfig) uint32 {
-	// all I2C interfaces are on APB1 (42 MHz)
-	clock := CPUFrequency() / 4
-	// convert to MHz
-	clock /= 1000000
-	// must be between 2 MHz (or 4 MHz for fast mode (Fm)) and 50 MHz, inclusive
-	var min, max uint32 = 2, 50
-	if config.Frequency > 100000 {
-		min = 4 // fast mode (Fm)
-	}
-	if clock < min {
-		clock = min
-	} else if clock > max {
-		clock = max
-	}
-	return clock << stm32.I2C_CR2_FREQ_Pos
-}
-
-func (i2c I2C) getRiseTime(config I2CConfig) uint32 {
-	// These bits must be programmed with the maximum SCL rise time given in the
-	// I2C bus specification, incremented by 1.
-	// For instance: in Sm mode, the maximum allowed SCL rise time is 1000 ns.
-	// If, in the I2C_CR2 register, the value of FREQ[5:0] bits is equal to 0x08
-	// and PCLK1 = 125 ns, therefore the TRISE[5:0] bits must be programmed with
-	// 09h (1000 ns / 125 ns = 8 + 1)
-	freqRange := i2c.getFreqRange(config)
-	if config.Frequency > 100000 {
-		// fast mode (Fm) adjustment
-		freqRange *= 300
-		freqRange /= 1000
-	}
-	return (freqRange + 1) << stm32.I2C_TRISE_TRISE_Pos
-}
-
-func (i2c I2C) getSpeed(config I2CConfig) uint32 {
-	ccr := func(pclk uint32, freq uint32, coeff uint32) uint32 {
-		return (((pclk - 1) / (freq * coeff)) + 1) & stm32.I2C_CCR_CCR_Msk
-	}
-	sm := func(pclk uint32, freq uint32) uint32 { // standard mode (Sm)
-		if s := ccr(pclk, freq, 2); s < 4 {
-			return 4
-		} else {
-			return s
-		}
-	}
-	fm := func(pclk uint32, freq uint32, duty uint8) uint32 { // fast mode (Fm)
-		if duty == DutyCycle2 {
-			return ccr(pclk, freq, 3)
-		} else {
-			return ccr(pclk, freq, 25) | stm32.I2C_CCR_DUTY
-		}
-	}
-	// all I2C interfaces are on APB1 (42 MHz)
-	clock := CPUFrequency() / 4
-	if config.Frequency <= 100000 {
-		return sm(clock, config.Frequency)
-	} else {
-		s := fm(clock, config.Frequency, config.DutyCycle)
-		if (s & stm32.I2C_CCR_CCR_Msk) == 0 {
-			return 1
-		} else {
-			return s | stm32.I2C_CCR_F_S
-		}
-	}
-}