4e8453167f
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.
41 строка
3 КиБ
LLVM
41 строка
3 КиБ
LLVM
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._interface = type { i8*, i8* }
|
|
|
|
@"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 {
|
|
; return typ.Implements(errorType)
|
|
; }
|
|
; 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(i8* %typ.typecode, i8* %typ.value, i8* %context) {
|
|
entry:
|
|
%result = call i1 @"reflect.Type.Implements$invoke"(i8* %typ.value, i8* getelementptr inbounds ({ i8*, i8, i8* }, { i8*, i8, i8* }* @"reflect/types.type:pointer:named:reflect.rawType", i32 0, i32 1), i8* getelementptr inbounds ({ i8, i8*, i8* }, { i8, i8*, i8* }* @"reflect/types.type:named:error", i32 0, i32 0), i8* %typ.typecode, i8* undef)
|
|
ret i1 %result
|
|
}
|
|
|
|
; This Implements method call can not be optimized because itf is not known at
|
|
; compile time.
|
|
; func isUnknown(typ, itf reflect.Type) bool {
|
|
; return typ.Implements(itf)
|
|
; }
|
|
define i1 @main.isUnknown(i8* %typ.typecode, i8* %typ.value, i8* %itf.typecode, i8* %itf.value, i8* %context) {
|
|
entry:
|
|
%result = call i1 @"reflect.Type.Implements$invoke"(i8* %typ.value, i8* %itf.typecode, i8* %itf.value, i8* %typ.typecode, i8* undef)
|
|
ret i1 %result
|
|
}
|
|
|
|
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" }
|