all: refactor reflect package

This is a big commit that changes the way runtime type information is stored in
the binary. Instead of compressing it and storing it in a number of sidetables,
it is stored similar to how the Go compiler toolchain stores it (but still more
compactly).

This has a number of advantages:

  * It is much easier to add new features to reflect support. They can simply
    be added to these structs without requiring massive changes (especially in
    the reflect lowering pass).
  * It removes the reflect lowering pass, which was a large amount of hard to
    understand and debug code.
  * The reflect lowering pass also required merging all LLVM IR into one
    module, which is terrible for performance especially when compiling large
    amounts of code. See issue 2870 for details.
  * It is (probably!) easier to reason about for the compiler.

The downside is that it increases code size a bit, especially when reflect is
involved. I hope to fix some of that in later patches.
This commit is contained in:
Ayke van Laethem
2022-06-24 00:09:03 +02:00
committed by Ron Evans
parent ebb410afd9
commit 4e8453167f
27 changed files with 791 additions and 1346 deletions
+13 -18
View File
@@ -1,19 +1,14 @@
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"
%runtime.typecodeID = type { %runtime.typecodeID*, i32, %runtime.interfaceMethodInfo*, %runtime.typecodeID*, i32 }
%runtime.interfaceMethodInfo = type { i8*, i32 }
%runtime._interface = type { i8*, i8* }
@"reflect/types.type:named:error" = linkonce_odr constant %runtime.typecodeID { %runtime.typecodeID* @"reflect/types.type:interface:{Error:func:{}{basic:string}}", i32 0, %runtime.interfaceMethodInfo* null, %runtime.typecodeID* null, i32 ptrtoint (i1 (i32)* @"error.$typeassert" to i32) }
@"reflect/types.type:interface:{Error:func:{}{basic:string}}" = linkonce_odr constant %runtime.typecodeID { %runtime.typecodeID* bitcast ([1 x i8*]* @"reflect/types.interface:interface{Error() string}$interface" to %runtime.typecodeID*), i32 0, %runtime.interfaceMethodInfo* null, %runtime.typecodeID* null, i32 ptrtoint (i1 (i32)* @"error.$typeassert" to i32) }
@"reflect/methods.Error() string" = linkonce_odr constant i8 0
@"reflect/types.interface:interface{Error() string}$interface" = linkonce_odr constant [1 x i8*] [i8* @"reflect/methods.Error() string"]
@"reflect/methods.Align() int" = linkonce_odr constant i8 0
@"reflect/methods.Implements(reflect.Type) bool" = linkonce_odr constant i8 0
@"reflect.Type$interface" = linkonce_odr constant [2 x i8*] [i8* @"reflect/methods.Align() int", i8* @"reflect/methods.Implements(reflect.Type) bool"]
@"reflect/types.type:named:reflect.rawType" = linkonce_odr constant %runtime.typecodeID { %runtime.typecodeID* @"reflect/types.type:basic:uintptr", i32 0, %runtime.interfaceMethodInfo* getelementptr inbounds ([20 x %runtime.interfaceMethodInfo], [20 x %runtime.interfaceMethodInfo]* @"reflect.rawType$methodset", i32 0, i32 0), %runtime.typecodeID* null, i32 0 }
@"reflect.rawType$methodset" = linkonce_odr constant [20 x %runtime.interfaceMethodInfo] zeroinitializer
@"reflect/types.type:basic:uintptr" = linkonce_odr constant %runtime.typecodeID zeroinitializer
@"reflect/types.type:named:error" = internal constant { i8, i8*, i8* } { i8 52, i8* getelementptr inbounds ({ i8, i8* }, { i8, i8* }* @"reflect/types.type:pointer:named:error", i32 0, i32 0), i8* getelementptr inbounds ({ i8, i8* }, { i8, i8* }* @"reflect/types.type:interface:{Error:func:{}{basic:string}}", i32 0, i32 0) }, align 4
@"reflect/types.type:interface:{Error:func:{}{basic:string}}" = internal constant { i8, i8* } { i8 20, i8* getelementptr inbounds ({ i8, i8* }, { i8, i8* }* @"reflect/types.type:pointer:interface:{Error:func:{}{basic:string}}", i32 0, i32 0) }, align 4
@"reflect/types.type:pointer:interface:{Error:func:{}{basic:string}}" = internal constant { i8, i8* } { i8 21, i8* getelementptr inbounds ({ i8, i8* }, { i8, i8* }* @"reflect/types.type:interface:{Error:func:{}{basic:string}}", i32 0, i32 0) }, align 4
@"reflect/types.type:pointer:named:error" = internal constant { i8, i8* } { i8 21, i8* getelementptr inbounds ({ i8, i8*, i8* }, { i8, i8*, i8* }* @"reflect/types.type:named:error", i32 0, i32 0) }, align 4
@"reflect/types.type:pointer:named:reflect.rawType" = internal constant { i8*, i8, i8* } { i8* null, i8 21, i8* null }, align 4
@"reflect/methods.Implements(reflect.Type) bool" = internal constant i8 0, align 1
; var errorType = reflect.TypeOf((*error)(nil)).Elem()
; func isError(typ reflect.Type) bool {
@@ -22,9 +17,9 @@ target triple = "i686--linux"
; The type itself is stored in %typ.value, %typ.typecode just refers to the
; type of reflect.Type. This function can be optimized because errorType is
; known at compile time (after the interp pass has run).
define i1 @main.isError(i32 %typ.typecode, i8* %typ.value, i8* %context) {
define i1 @main.isError(i8* %typ.typecode, i8* %typ.value, i8* %context) {
entry:
%result = call i1 @"reflect.Type.Implements$invoke"(i8* %typ.value, i32 ptrtoint (%runtime.typecodeID* @"reflect/types.type:named:reflect.rawType" to i32), i8* bitcast (%runtime.typecodeID* @"reflect/types.type:named:error" to i8*), i32 %typ.typecode, i8* undef)
%result = call i1 @"reflect.Type.Implements$invoke"(i8* %typ.value, i8* getelementptr inbounds ({ i8*, i8, i8* }, { i8*, i8, i8* }* @"reflect/types.type:pointer:named:reflect.rawType", i32 0, i32 1), i8* getelementptr inbounds ({ i8, i8*, i8* }, { i8, i8*, i8* }* @"reflect/types.type:named:error", i32 0, i32 0), i8* %typ.typecode, i8* undef)
ret i1 %result
}
@@ -33,14 +28,14 @@ entry:
; func isUnknown(typ, itf reflect.Type) bool {
; return typ.Implements(itf)
; }
define i1 @main.isUnknown(i32 %typ.typecode, i8* %typ.value, i32 %itf.typecode, i8* %itf.value, i8* %context) {
define i1 @main.isUnknown(i8* %typ.typecode, i8* %typ.value, i8* %itf.typecode, i8* %itf.value, i8* %context) {
entry:
%result = call i1 @"reflect.Type.Implements$invoke"(i8* %typ.value, i32 %itf.typecode, i8* %itf.value, i32 %typ.typecode, i8* undef)
%result = call i1 @"reflect.Type.Implements$invoke"(i8* %typ.value, i8* %itf.typecode, i8* %itf.value, i8* %typ.typecode, i8* undef)
ret i1 %result
}
declare i1 @"reflect.Type.Implements$invoke"(i8*, i32, i8*, i32, i8*) #0
declare i1 @"error.$typeassert"(i32) #1
declare i1 @"reflect.Type.Implements$invoke"(i8*, i8*, i8*, i8*, i8*) #0
declare i1 @"interface:{Error:func:{}{basic:string}}.$typeassert"(i8* %0) #1
attributes #0 = { "tinygo-invoke"="reflect/methods.Implements(reflect.Type) bool" "tinygo-methods"="reflect/methods.Align() int; reflect/methods.Implements(reflect.Type) bool" }
attributes #1 = { "tinygo-methods"="reflect/methods.Error() string" }