Instead of always starting a new goroutine for the main goroutine, run
the main goroutine on the system stack.
The system stack is not occupied with scheduling, instead each goroutine
that wants to pause itself calls into the scheduler which will switch to
the next task (goroutine) to run, or sleeps.
There are various advantages of this over the previous system:
* When the program doesn't start a goroutine, the code size and RAM
consumption is close to what you'd get with `-scheduler=none`.
* When the program does start a goroutine, there is still a reduction
in RAM consumption because only one extra stack is needed.
* Because tasks directly switch to the next task to run, only a single
task switch is needed instead of two (goroutine -> scheduler ->
goroutine). This should improve task switching performance.
I kept the current behavior for WebAssembly/Asyncify. I looked into how
the same benefits can be realized for WebAssembly but couldn't easily
find how to do that. Maybe this can be done separately, or maybe we'll
just wait for the stack switching proposal to finish.
The code for Cortex-M is currently more complicated than I'd like, and
therefore can sometimes result in a slight increase in code size. I'd
like to fix this eventually but am still looking into good ways to do
this. I still think this change is generally beneficial because many
programs see big reductions in code size when compiling for Cortex-M.
This commit will start to use a few more WebAssembly features, such as
bulk memory operations. This results in a significant code size saving.
How much it saves varies a lot but it's typically around 1300 bytes.
This change is possible by bumping our minimum Node.js version to 14.
The previous LTS version (12) has been marked end of life, so we can
start to depend on features in the current oldest LTS version, which is
version 14. Browsers have been supporting these features for a long time
now, it's just Node.js that prevented us doing this before.
This change adds support for compiler-rt, which supports float64 (unlike
libgcc for AVR). This gets a number of tests to pass that require
float64 support.
We're still using libgcc with this change, but libgcc will probably be
removed eventually once AVR support in compiler-rt is a bit more mature.
I've also pushed a fix for a small regression in our
xtensa_release_14.0.0-patched LLVM branch that has also been merged
upstream. Without it, a floating point comparison against zero always
returns true which is certainly a bug. It is necessary to correctly
print floating point values.
This patch changes two things:
1. It changes the default stack size. Without this change, the
goroutine.go test doesn't pass (apparently there's some memory
corruption).
2. It moves the excluded tests so that they are skipped with a regular
`-target=simavr`, not just when running all tests (without
`-target`).
This matches the flash-command and is generally a bit easier to work
with.
This commit also prepares for allowing multiple formats to be used in
the emulator command, which is necessary for the esp32.
Switch over to LLVM 14 for static builds. Keep using LLVM 13 for regular
builds for now.
This uses a branch of the upstream Espressif branch to fix an issue,
see: https://github.com/espressif/llvm-project/pull/59
Exporting symbols seems to embed them in the WASM exports section which
causes wasmtime to fail: https://github.com/bytecodealliance/wasmtime/issues/2587
As a workaround, it is possible to specify the `--allow-unknown-exports`
flag on wasmtime.
But as discussed in the above linked issue, this seems to only be a
workaround. For the Rust compiler the fix was to remove the
`--export-dynamic` linker flag when targeting `wasm32-wasi`:
https://github.com/rust-lang/rust/pull/81255
Which is waht this commit does for Tinygo too.
This adds support for building with `-tags=llvm13` and switches to LLVM
13 for tinygo binaries that are statically linked against LLVM.
Some notes on this commit:
* Added `-mfloat-abi=soft` to all Cortex-M targets because otherwise
nrfx would complain that floating point was enabled on Cortex-M0.
That's not the case, but with `-mfloat-abi=soft` the `__SOFTFP__`
macro is defined which silences this warning.
See: https://reviews.llvm.org/D100372
* Changed from `--sysroot=<root>` to `-nostdlib -isystem <root>` for
musl because with Clang 13, even with `--sysroot` some system
libraries are used which we don't want.
* Changed all `-Xclang -internal-isystem -Xclang` to simply
`-isystem`, for consistency with the above change. It appears to
have the same effect.
* Moved WebAssembly function declarations to the top of the file in
task_asyncify_wasm.S because (apparently) the assembler has become
more strict.
This change implements a new "scheduler" for WebAssembly using binaryen's asyncify transform.
This is more reliable than the current "coroutines" transform, and works with non-Go code in the call stack.
runtime (js/wasm): handle scheduler nesting
If WASM calls into JS which calls back into WASM, it is possible for the scheduler to nest.
The event from the callback must be handled immediately, so the task cannot simply be deferred to the outer scheduler.
This creates a minimal scheduler loop which is used to handle such nesting.
Ayke van Laethem
Kenneth Bell
deadprogram
sago35
Daniel Esteban
Damian Gryski
Yurii Soldak
Olaf Flebbe
Elliott Sales de Andrade
Sai Sasidhar Maddali
Dmitriy
ZauberNerd
Samuel Stauffer
BCG
Elias Naur
Nia Waldvogel
Olivier Fauchon