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go/test/codegen/strings.go
Cuong Manh Le 0f8dffd0aa all: use ":" for compiler generated symbols
As it can't appear in user package paths.

There is a hack for handling "go:buildid" and "type:*" on windows/386.

Previously, windows/386 requires underscore prefix on external symbols,
but that's only applied for SHOSTOBJ/SUNDEFEXT or cgo export symbols.
"go.buildid" is STEXT, "type.*" is STYPE, thus they are not prefixed
with underscore.

In external linking mode, the external linker can't resolve them as
external symbols. But we are lucky that they have "." in their name,
so the external linker see them as Forwarder RVA exports. See:

 - https://docs.microsoft.com/en-us/windows/win32/debug/pe-format#export-address-table
 - https://sourceware.org/git/?p=binutils-gdb.git;a=blob;f=ld/pe-dll.c;h=e7b82ba6ffadf74dc1b9ee71dc13d48336941e51;hb=HEAD#l972)

This CL changes "." to ":" in symbols name, so theses symbols can not be
found by external linker anymore. So a hacky way is adding the
underscore prefix for these 2 symbols. I don't have enough knowledge to
verify whether adding the underscore for all STEXT/STYPE symbols are
fine, even if it could be, that would be done in future CL.

Fixes #37762

Change-Id: I92eaaf24c0820926a36e0530fdb07b07af1fcc35
Reviewed-on: https://go-review.googlesource.com/c/go/+/317917
Reviewed-by: Than McIntosh <thanm@google.com>
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
2022-08-09 11:28:56 +00:00

66 lines
2.1 KiB
Go

// asmcheck
// Copyright 2018 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package codegen
// This file contains code generation tests related to the handling of
// string types.
func CountRunes(s string) int { // Issue #24923
// amd64:`.*countrunes`
return len([]rune(s))
}
func ToByteSlice() []byte { // Issue #24698
// amd64:`LEAQ\ttype:\[3\]uint8`
// amd64:`CALL\truntime\.newobject`
// amd64:-`.*runtime.stringtoslicebyte`
return []byte("foo")
}
// Loading from read-only symbols should get transformed into constants.
func ConstantLoad() {
// 12592 = 0x3130
// 50 = 0x32
// amd64:`MOVW\t\$12592, \(`,`MOVB\t\$50, 2\(`
// 386:`MOVW\t\$12592, \(`,`MOVB\t\$50, 2\(`
// arm:`MOVW\t\$48`,`MOVW\t\$49`,`MOVW\t\$50`
// arm64:`MOVD\t\$12592`,`MOVD\t\$50`
// wasm:`I64Const\t\$12592`,`I64Store16\t\$0`,`I64Const\t\$50`,`I64Store8\t\$2`
// mips64:`MOVV\t\$48`,`MOVV\t\$49`,`MOVV\t\$50`
bsink = []byte("012")
// 858927408 = 0x33323130
// 13620 = 0x3534
// amd64:`MOVL\t\$858927408`,`MOVW\t\$13620, 4\(`
// 386:`MOVL\t\$858927408`,`MOVW\t\$13620, 4\(`
// arm64:`MOVD\t\$858927408`,`MOVD\t\$13620`
// wasm:`I64Const\t\$858927408`,`I64Store32\t\$0`,`I64Const\t\$13620`,`I64Store16\t\$4`
bsink = []byte("012345")
// 3978425819141910832 = 0x3736353433323130
// 7306073769690871863 = 0x6564636261393837
// amd64:`MOVQ\t\$3978425819141910832`,`MOVQ\t\$7306073769690871863`
// 386:`MOVL\t\$858927408, \(`,`DUFFCOPY`
// arm64:`MOVD\t\$3978425819141910832`,`MOVD\t\$1650538808`,`MOVD\t\$25699`,`MOVD\t\$101`
// wasm:`I64Const\t\$3978425819141910832`,`I64Store\t\$0`,`I64Const\t\$7306073769690871863`,`I64Store\t\$7`
bsink = []byte("0123456789abcde")
// 56 = 0x38
// amd64:`MOVQ\t\$3978425819141910832`,`MOVB\t\$56`
bsink = []byte("012345678")
// 14648 = 0x3938
// amd64:`MOVQ\t\$3978425819141910832`,`MOVW\t\$14648`
bsink = []byte("0123456789")
// 1650538808 = 0x62613938
// amd64:`MOVQ\t\$3978425819141910832`,`MOVL\t\$1650538808`
bsink = []byte("0123456789ab")
}
var bsink []byte