golang asm 代码
文件路径：/src/cmd/link/internal/mips64/asm.go
/ Inferno utils/5l/asm.c
/ https://bitbucket.org/inferno-os/inferno-os/src/master/utils/5l/asm.c
/
/ Copyright © 1994-1999 Lucent Technologies Inc. All rights reserved.
/ Portions Copyright © 1995-1997 C H Forsyth (forsyth@terzarima.net)
/ Portions Copyright © 1997-1999 Vita Nuova Limited
/ Portions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com)
/ Portions Copyright © 2004,2006 Bruce Ellis
/ Portions Copyright © 2005-2007 C H Forsyth (forsyth@terzarima.net)
/ Revisions Copyright © 2000-2007 Lucent Technologies Inc. and others
/ Portions Copyright © 2009 The Go Authors. All rights reserved.
/
/ Permission is hereby granted, free of charge, to any person obtaining a copy
/ of this software and associated documentation files (the "Software"), to deal
/ in the Software without restriction, including without limitation the rights
/ to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
/ copies of the Software, and to permit persons to whom the Software is
/ furnished to do so, subject to the following conditions:
/
/ The above copyright notice and this permission notice shall be included in
/ all copies or substantial portions of the Software.
/
/ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
/ IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
/ FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
/ AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
/ LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
/ OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
/ THE SOFTWARE.
package mips64
import (
"cmd/internal/objabi"
"cmd/internal/sys"
"cmd/link/internal/ld"
"cmd/link/internal/loader"
"cmd/link/internal/sym"
"debug/elf"
)
func gentext(ctxt *ld.Link, ldr *loader.Loader) {}
func elfreloc1(ctxt *ld.Link, out *ld.OutBuf, ldr *loader.Loader, s loader.Sym, r loader.ExtReloc, ri int, sectoff int64) bool {
/ mips64 ELF relocation (endian neutral)
/ offset uint64
/ sym uint32
/ ssym uint8
/ type3 uint8
/ type2 uint8
/ type uint8
/ addend int64
addend := r.Xadd
out.Write64(uint64(sectoff))
elfsym := ld.ElfSymForReloc(ctxt, r.Xsym)
out.Write32(uint32(elfsym))
out.Write8(0)
out.Write8(0)
out.Write8(0)
switch r.Type {
default:
return false
case objabi.R_ADDR, objabi.R_DWARFSECREF:
switch r.Size {
case 4:
out.Write8(uint8(elf.R_MIPS_32))
case 8:
out.Write8(uint8(elf.R_MIPS_64))
default:
return false
}
case objabi.R_ADDRMIPS:
out.Write8(uint8(elf.R_MIPS_LO16))
case objabi.R_ADDRMIPSU:
out.Write8(uint8(elf.R_MIPS_HI16))
case objabi.R_ADDRMIPSTLS:
out.Write8(uint8(elf.R_MIPS_TLS_TPREL_LO16))
if ctxt.Target.IsOpenbsd() {
/ OpenBSD mips64 does not currently offset TLS by 0x7000,
/ as such we need to add this back to get the correct offset
/ via the external linker.
addend += 0x7000
}
case objabi.R_CALLMIPS,
objabi.R_JMPMIPS:
out.Write8(uint8(elf.R_MIPS_26))
}
out.Write64(uint64(addend))
return true
}
func elfsetupplt(ctxt *ld.Link, plt, gotplt *loader.SymbolBuilder, dynamic loader.Sym) {
return
}
func machoreloc1(*sys.Arch, *ld.OutBuf, *loader.Loader, loader.Sym, loader.ExtReloc, int64) bool {
return false
}
func archreloc(target *ld.Target, ldr *loader.Loader, syms *ld.ArchSyms, r loader.Reloc, s loader.Sym, val int64) (o int64, nExtReloc int, ok bool) {
if target.IsExternal() {
switch r.Type() {
default:
return val, 0, false
case objabi.R_ADDRMIPS,
objabi.R_ADDRMIPSU,
objabi.R_ADDRMIPSTLS,
objabi.R_CALLMIPS,
objabi.R_JMPMIPS:
return val, 1, true
}
}
const isOk = true
const noExtReloc = 0
rs := r.Sym()
switch r.Type() {
case objabi.R_ADDRMIPS,
objabi.R_ADDRMIPSU:
t := ldr.SymValue(rs) + r.Add()
if r.Type() == objabi.R_ADDRMIPS {
return int64(val&0xffff0000 | t&0xffff), noExtReloc, isOk
}
return int64(val&0xffff0000 | ((t+1<<15)>>16)&0xffff), noExtReloc, isOk
case objabi.R_ADDRMIPSTLS:
/ thread pointer is at 0x7000 offset from the start of TLS data area
t := ldr.SymValue(rs) + r.Add() - 0x7000
if target.IsOpenbsd() {
/ OpenBSD mips64 does not currently offset TLS by 0x7000,
/ as such we need to add this back to get the correct offset.
t += 0x7000
}
if t < -32768 || t >= 32678 {
ldr.Errorf(s, "TLS offset out of range %d", t)
}
return int64(val&0xffff0000 | t&0xffff), noExtReloc, isOk
case objabi.R_CALLMIPS,
objabi.R_JMPMIPS:
/ Low 26 bits = (S + A) >> 2
t := ldr.SymValue(rs) + r.Add()
return int64(val&0xfc000000 | (t>>2)&^0xfc000000), noExtReloc, isOk
}
return val, 0, false
}
func archrelocvariant(*ld.Target, *loader.Loader, loader.Reloc, sym.RelocVariant, loader.Sym, int64, []byte) int64 {
return -1
}
func extreloc(target *ld.Target, ldr *loader.Loader, r loader.Reloc, s loader.Sym) (loader.ExtReloc, bool) {
switch r.Type() {
case objabi.R_ADDRMIPS,
objabi.R_ADDRMIPSU:
return ld.ExtrelocViaOuterSym(ldr, r, s), true
case objabi.R_ADDRMIPSTLS,
objabi.R_CALLMIPS,
objabi.R_JMPMIPS:
return ld.ExtrelocSimple(ldr, r), true
}
return loader.ExtReloc{}, false
}