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// Inferno utils/5l/asm.c
// https://bitbucket.org/inferno-os/inferno-os/src/default/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 arm64
import (
"cmd/internal/objabi"
"cmd/internal/sys"
"cmd/link/internal/ld"
"cmd/link/internal/sym"
"debug/elf"
"encoding/binary"
"fmt"
"log"
)
func gentext(ctxt *ld.Link) {
if !ctxt.DynlinkingGo() {
return
}
addmoduledata := ctxt.Syms.Lookup("runtime.addmoduledata", 0)
if addmoduledata.Type == sym.STEXT && ctxt.BuildMode != ld.BuildModePlugin {
// we're linking a module containing the runtime -> no need for
// an init function
return
}
addmoduledata.Attr |= sym.AttrReachable
initfunc := ctxt.Syms.Lookup("go.link.addmoduledata", 0)
initfunc.Type = sym.STEXT
initfunc.Attr |= sym.AttrLocal
initfunc.Attr |= sym.AttrReachable
o := func(op uint32) {
initfunc.AddUint32(ctxt.Arch, op)
}
// 0000000000000000 <local.dso_init>:
// 0: 90000000 adrp x0, 0 <runtime.firstmoduledata>
// 0: R_AARCH64_ADR_PREL_PG_HI21 local.moduledata
// 4: 91000000 add x0, x0, #0x0
// 4: R_AARCH64_ADD_ABS_LO12_NC local.moduledata
o(0x90000000)
o(0x91000000)
rel := initfunc.AddRel()
rel.Off = 0
rel.Siz = 8
rel.Sym = ctxt.Moduledata
rel.Type = objabi.R_ADDRARM64
// 8: 14000000 b 0 <runtime.addmoduledata>
// 8: R_AARCH64_CALL26 runtime.addmoduledata
o(0x14000000)
rel = initfunc.AddRel()
rel.Off = 8
rel.Siz = 4
rel.Sym = ctxt.Syms.Lookup("runtime.addmoduledata", 0)
rel.Type = objabi.R_CALLARM64 // Really should be R_AARCH64_JUMP26 but doesn't seem to make any difference
if ctxt.BuildMode == ld.BuildModePlugin {
ctxt.Textp = append(ctxt.Textp, addmoduledata)
}
ctxt.Textp = append(ctxt.Textp, initfunc)
initarray_entry := ctxt.Syms.Lookup("go.link.addmoduledatainit", 0)
initarray_entry.Attr |= sym.AttrReachable
initarray_entry.Attr |= sym.AttrLocal
initarray_entry.Type = sym.SINITARR
initarray_entry.AddAddr(ctxt.Arch, initfunc)
}
// adddynrel implements just enough to support external linking to
// the system libc functions used by the runtime.
func adddynrel(ctxt *ld.Link, s *sym.Symbol, r *sym.Reloc) bool {
targ := r.Sym
switch r.Type {
case objabi.R_CALL,
objabi.R_PCREL,
objabi.R_CALLARM64:
if targ.Type != sym.SDYNIMPORT {
// nothing to do, the relocation will be laid out in reloc
return true
}
if ctxt.LinkMode == ld.LinkExternal {
// External linker will do this relocation.
return true
}
}
log.Fatalf("adddynrel not implemented for relocation type %d (%s)", r.Type, sym.RelocName(ctxt.Arch, r.Type))
return false
}
func elfreloc1(ctxt *ld.Link, r *sym.Reloc, sectoff int64) bool {
ctxt.Out.Write64(uint64(sectoff))
elfsym := r.Xsym.ElfsymForReloc()
switch r.Type {
default:
return false
case objabi.R_ADDR:
switch r.Siz {
case 4:
ctxt.Out.Write64(uint64(elf.R_AARCH64_ABS32) | uint64(elfsym)<<32)
case 8:
ctxt.Out.Write64(uint64(elf.R_AARCH64_ABS64) | uint64(elfsym)<<32)
default:
return false
}
case objabi.R_ADDRARM64:
// two relocations: R_AARCH64_ADR_PREL_PG_HI21 and R_AARCH64_ADD_ABS_LO12_NC
ctxt.Out.Write64(uint64(elf.R_AARCH64_ADR_PREL_PG_HI21) | uint64(elfsym)<<32)
ctxt.Out.Write64(uint64(r.Xadd))
ctxt.Out.Write64(uint64(sectoff + 4))
ctxt.Out.Write64(uint64(elf.R_AARCH64_ADD_ABS_LO12_NC) | uint64(elfsym)<<32)
case objabi.R_ARM64_TLS_LE:
ctxt.Out.Write64(uint64(elf.R_AARCH64_TLSLE_MOVW_TPREL_G0) | uint64(elfsym)<<32)
case objabi.R_ARM64_TLS_IE:
ctxt.Out.Write64(uint64(elf.R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21) | uint64(elfsym)<<32)
ctxt.Out.Write64(uint64(r.Xadd))
ctxt.Out.Write64(uint64(sectoff + 4))
ctxt.Out.Write64(uint64(elf.R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC) | uint64(elfsym)<<32)
case objabi.R_ARM64_GOTPCREL:
ctxt.Out.Write64(uint64(elf.R_AARCH64_ADR_GOT_PAGE) | uint64(elfsym)<<32)
ctxt.Out.Write64(uint64(r.Xadd))
ctxt.Out.Write64(uint64(sectoff + 4))
ctxt.Out.Write64(uint64(elf.R_AARCH64_LD64_GOT_LO12_NC) | uint64(elfsym)<<32)
case objabi.R_CALLARM64:
if r.Siz != 4 {
return false
}
ctxt.Out.Write64(uint64(elf.R_AARCH64_CALL26) | uint64(elfsym)<<32)
}
ctxt.Out.Write64(uint64(r.Xadd))
return true
}
func elfsetupplt(ctxt *ld.Link) {
// TODO(aram)
return
}
func machoreloc1(arch *sys.Arch, out *ld.OutBuf, s *sym.Symbol, r *sym.Reloc, sectoff int64) bool {
var v uint32
rs := r.Xsym
if rs.Type == sym.SHOSTOBJ || r.Type == objabi.R_CALLARM64 || r.Type == objabi.R_ADDRARM64 {
if rs.Dynid < 0 {
ld.Errorf(s, "reloc %d (%s) to non-macho symbol %s type=%d (%s)", r.Type, sym.RelocName(arch, r.Type), rs.Name, rs.Type, rs.Type)
return false
}
v = uint32(rs.Dynid)
v |= 1 << 27 // external relocation
} else {
v = uint32(rs.Sect.Extnum)
if v == 0 {
ld.Errorf(s, "reloc %d (%s) to symbol %s in non-macho section %s type=%d (%s)", r.Type, sym.RelocName(arch, r.Type), rs.Name, rs.Sect.Name, rs.Type, rs.Type)
return false
}
}
switch r.Type {
default:
return false
case objabi.R_ADDR:
v |= ld.MACHO_ARM64_RELOC_UNSIGNED << 28
case objabi.R_CALLARM64:
if r.Xadd != 0 {
ld.Errorf(s, "ld64 doesn't allow BR26 reloc with non-zero addend: %s+%d", rs.Name, r.Xadd)
}
v |= 1 << 24 // pc-relative bit
v |= ld.MACHO_ARM64_RELOC_BRANCH26 << 28
case objabi.R_ADDRARM64:
r.Siz = 4
// Two relocation entries: MACHO_ARM64_RELOC_PAGEOFF12 MACHO_ARM64_RELOC_PAGE21
// if r.Xadd is non-zero, add two MACHO_ARM64_RELOC_ADDEND.
if r.Xadd != 0 {
out.Write32(uint32(sectoff + 4))
out.Write32((ld.MACHO_ARM64_RELOC_ADDEND << 28) | (2 << 25) | uint32(r.Xadd&0xffffff))
}
out.Write32(uint32(sectoff + 4))
out.Write32(v | (ld.MACHO_ARM64_RELOC_PAGEOFF12 << 28) | (2 << 25))
if r.Xadd != 0 {
out.Write32(uint32(sectoff))
out.Write32((ld.MACHO_ARM64_RELOC_ADDEND << 28) | (2 << 25) | uint32(r.Xadd&0xffffff))
}
v |= 1 << 24 // pc-relative bit
v |= ld.MACHO_ARM64_RELOC_PAGE21 << 28
}
switch r.Siz {
default:
return false
case 1:
v |= 0 << 25
case 2:
v |= 1 << 25
case 4:
v |= 2 << 25
case 8:
v |= 3 << 25
}
out.Write32(uint32(sectoff))
out.Write32(v)
return true
}
func archreloc(ctxt *ld.Link, r *sym.Reloc, s *sym.Symbol, val int64) (int64, bool) {
if ctxt.LinkMode == ld.LinkExternal {
switch r.Type {
default:
return val, false
case objabi.R_ARM64_GOTPCREL:
var o1, o2 uint32
if ctxt.Arch.ByteOrder == binary.BigEndian {
o1 = uint32(val >> 32)
o2 = uint32(val)
} else {
o1 = uint32(val)
o2 = uint32(val >> 32)
}
// Any relocation against a function symbol is redirected to
// be against a local symbol instead (see putelfsym in
// symtab.go) but unfortunately the system linker was buggy
// when confronted with a R_AARCH64_ADR_GOT_PAGE relocation
// against a local symbol until May 2015
// (https://sourceware.org/bugzilla/show_bug.cgi?id=18270). So
// we convert the adrp; ld64 + R_ARM64_GOTPCREL into adrp;
// add + R_ADDRARM64.
if !(r.Sym.IsFileLocal() || r.Sym.Attr.VisibilityHidden() || r.Sym.Attr.Local()) && r.Sym.Type == sym.STEXT && ctxt.DynlinkingGo() {
if o2&0xffc00000 != 0xf9400000 {
ld.Errorf(s, "R_ARM64_GOTPCREL against unexpected instruction %x", o2)
}
o2 = 0x91000000 | (o2 & 0x000003ff)
r.Type = objabi.R_ADDRARM64
}
if ctxt.Arch.ByteOrder == binary.BigEndian {
val = int64(o1)<<32 | int64(o2)
} else {
val = int64(o2)<<32 | int64(o1)
}
fallthrough
case objabi.R_ADDRARM64:
r.Done = false
// set up addend for eventual relocation via outer symbol.
rs := r.Sym
r.Xadd = r.Add
for rs.Outer != nil {
r.Xadd += ld.Symaddr(rs) - ld.Symaddr(rs.Outer)
rs = rs.Outer
}
if rs.Type != sym.SHOSTOBJ && rs.Type != sym.SDYNIMPORT && rs.Sect == nil {
ld.Errorf(s, "missing section for %s", rs.Name)
}
r.Xsym = rs
// Note: ld64 currently has a bug that any non-zero addend for BR26 relocation
// will make the linking fail because it thinks the code is not PIC even though
// the BR26 relocation should be fully resolved at link time.
// That is the reason why the next if block is disabled. When the bug in ld64
// is fixed, we can enable this block and also enable duff's device in cmd/7g.
if false && ctxt.HeadType == objabi.Hdarwin {
var o0, o1 uint32
if ctxt.Arch.ByteOrder == binary.BigEndian {
o0 = uint32(val >> 32)
o1 = uint32(val)
} else {
o0 = uint32(val)
o1 = uint32(val >> 32)
}
// Mach-O wants the addend to be encoded in the instruction
// Note that although Mach-O supports ARM64_RELOC_ADDEND, it
// can only encode 24-bit of signed addend, but the instructions
// supports 33-bit of signed addend, so we always encode the
// addend in place.
o0 |= (uint32((r.Xadd>>12)&3) << 29) | (uint32((r.Xadd>>12>>2)&0x7ffff) << 5)
o1 |= uint32(r.Xadd&0xfff) << 10
r.Xadd = 0
// when laid out, the instruction order must always be o1, o2.
if ctxt.Arch.ByteOrder == binary.BigEndian {
val = int64(o0)<<32 | int64(o1)
} else {
val = int64(o1)<<32 | int64(o0)
}
}
return val, true
case objabi.R_CALLARM64,
objabi.R_ARM64_TLS_LE,
objabi.R_ARM64_TLS_IE:
r.Done = false
r.Xsym = r.Sym
r.Xadd = r.Add
return val, true
}
}
switch r.Type {
case objabi.R_CONST:
return r.Add, true
case objabi.R_GOTOFF:
return ld.Symaddr(r.Sym) + r.Add - ld.Symaddr(ctxt.Syms.Lookup(".got", 0)), true
case objabi.R_ADDRARM64:
t := ld.Symaddr(r.Sym) + r.Add - ((s.Value + int64(r.Off)) &^ 0xfff)
if t >= 1<<32 || t < -1<<32 {
ld.Errorf(s, "program too large, address relocation distance = %d", t)
}
var o0, o1 uint32
if ctxt.Arch.ByteOrder == binary.BigEndian {
o0 = uint32(val >> 32)
o1 = uint32(val)
} else {
o0 = uint32(val)
o1 = uint32(val >> 32)
}
o0 |= (uint32((t>>12)&3) << 29) | (uint32((t>>12>>2)&0x7ffff) << 5)
o1 |= uint32(t&0xfff) << 10
// when laid out, the instruction order must always be o1, o2.
if ctxt.Arch.ByteOrder == binary.BigEndian {
return int64(o0)<<32 | int64(o1), true
}
return int64(o1)<<32 | int64(o0), true
case objabi.R_ARM64_TLS_LE:
r.Done = false
if ctxt.HeadType != objabi.Hlinux {
ld.Errorf(s, "TLS reloc on unsupported OS %v", ctxt.HeadType)
}
// The TCB is two pointers. This is not documented anywhere, but is
// de facto part of the ABI.
v := r.Sym.Value + int64(2*ctxt.Arch.PtrSize)
if v < 0 || v >= 32678 {
ld.Errorf(s, "TLS offset out of range %d", v)
}
return val | (v << 5), true
case objabi.R_CALLARM64:
t := (ld.Symaddr(r.Sym) + r.Add) - (s.Value + int64(r.Off))
if t >= 1<<27 || t < -1<<27 {
ld.Errorf(s, "program too large, call relocation distance = %d", t)
}
return val | ((t >> 2) & 0x03ffffff), true
}
return val, false
}
func archrelocvariant(ctxt *ld.Link, r *sym.Reloc, s *sym.Symbol, t int64) int64 {
log.Fatalf("unexpected relocation variant")
return -1
}
func asmb(ctxt *ld.Link) {
if ctxt.Debugvlog != 0 {
ctxt.Logf("%5.2f asmb\n", ld.Cputime())
}
if ctxt.IsELF {
ld.Asmbelfsetup()
}
sect := ld.Segtext.Sections[0]
ctxt.Out.SeekSet(int64(sect.Vaddr - ld.Segtext.Vaddr + ld.Segtext.Fileoff))
ld.Codeblk(ctxt, int64(sect.Vaddr), int64(sect.Length))
for _, sect = range ld.Segtext.Sections[1:] {
ctxt.Out.SeekSet(int64(sect.Vaddr - ld.Segtext.Vaddr + ld.Segtext.Fileoff))
ld.Datblk(ctxt, int64(sect.Vaddr), int64(sect.Length))
}
if ld.Segrodata.Filelen > 0 {
if ctxt.Debugvlog != 0 {
ctxt.Logf("%5.2f rodatblk\n", ld.Cputime())
}
ctxt.Out.SeekSet(int64(ld.Segrodata.Fileoff))
ld.Datblk(ctxt, int64(ld.Segrodata.Vaddr), int64(ld.Segrodata.Filelen))
}
if ld.Segrelrodata.Filelen > 0 {
if ctxt.Debugvlog != 0 {
ctxt.Logf("%5.2f relrodatblk\n", ld.Cputime())
}
ctxt.Out.SeekSet(int64(ld.Segrelrodata.Fileoff))
ld.Datblk(ctxt, int64(ld.Segrelrodata.Vaddr), int64(ld.Segrelrodata.Filelen))
}
if ctxt.Debugvlog != 0 {
ctxt.Logf("%5.2f datblk\n", ld.Cputime())
}
ctxt.Out.SeekSet(int64(ld.Segdata.Fileoff))
ld.Datblk(ctxt, int64(ld.Segdata.Vaddr), int64(ld.Segdata.Filelen))
ctxt.Out.SeekSet(int64(ld.Segdwarf.Fileoff))
ld.Dwarfblk(ctxt, int64(ld.Segdwarf.Vaddr), int64(ld.Segdwarf.Filelen))
machlink := uint32(0)
if ctxt.HeadType == objabi.Hdarwin {
machlink = uint32(ld.Domacholink(ctxt))
}
/* output symbol table */
ld.Symsize = 0
ld.Lcsize = 0
symo := uint32(0)
if !*ld.FlagS {
// TODO: rationalize
if ctxt.Debugvlog != 0 {
ctxt.Logf("%5.2f sym\n", ld.Cputime())
}
switch ctxt.HeadType {
default:
if ctxt.IsELF {
symo = uint32(ld.Segdwarf.Fileoff + ld.Segdwarf.Filelen)
symo = uint32(ld.Rnd(int64(symo), int64(*ld.FlagRound)))
}
case objabi.Hplan9:
symo = uint32(ld.Segdata.Fileoff + ld.Segdata.Filelen)
case objabi.Hdarwin:
symo = uint32(ld.Segdwarf.Fileoff + uint64(ld.Rnd(int64(ld.Segdwarf.Filelen), int64(*ld.FlagRound))) + uint64(machlink))
}
ctxt.Out.SeekSet(int64(symo))
switch ctxt.HeadType {
default:
if ctxt.IsELF {
if ctxt.Debugvlog != 0 {
ctxt.Logf("%5.2f elfsym\n", ld.Cputime())
}
ld.Asmelfsym(ctxt)
ctxt.Out.Flush()
ctxt.Out.Write(ld.Elfstrdat)
if ctxt.LinkMode == ld.LinkExternal {
ld.Elfemitreloc(ctxt)
}
}
case objabi.Hplan9:
ld.Asmplan9sym(ctxt)
ctxt.Out.Flush()
sym := ctxt.Syms.Lookup("pclntab", 0)
if sym != nil {
ld.Lcsize = int32(len(sym.P))
ctxt.Out.Write(sym.P)
ctxt.Out.Flush()
}
case objabi.Hdarwin:
if ctxt.LinkMode == ld.LinkExternal {
ld.Machoemitreloc(ctxt)
}
}
}
if ctxt.Debugvlog != 0 {
ctxt.Logf("%5.2f header\n", ld.Cputime())
}
ctxt.Out.SeekSet(0)
switch ctxt.HeadType {
default:
case objabi.Hplan9: /* plan 9 */
ctxt.Out.Write32(0x647) /* magic */
ctxt.Out.Write32(uint32(ld.Segtext.Filelen)) /* sizes */
ctxt.Out.Write32(uint32(ld.Segdata.Filelen))
ctxt.Out.Write32(uint32(ld.Segdata.Length - ld.Segdata.Filelen))
ctxt.Out.Write32(uint32(ld.Symsize)) /* nsyms */
ctxt.Out.Write32(uint32(ld.Entryvalue(ctxt))) /* va of entry */
ctxt.Out.Write32(0)
ctxt.Out.Write32(uint32(ld.Lcsize))
case objabi.Hlinux,
objabi.Hfreebsd,
objabi.Hnetbsd,
objabi.Hopenbsd,
objabi.Hnacl:
ld.Asmbelf(ctxt, int64(symo))
case objabi.Hdarwin:
ld.Asmbmacho(ctxt)
}
ctxt.Out.Flush()
if *ld.FlagC {
fmt.Printf("textsize=%d\n", ld.Segtext.Filelen)
fmt.Printf("datsize=%d\n", ld.Segdata.Filelen)
fmt.Printf("bsssize=%d\n", ld.Segdata.Length-ld.Segdata.Filelen)
fmt.Printf("symsize=%d\n", ld.Symsize)
fmt.Printf("lcsize=%d\n", ld.Lcsize)
fmt.Printf("total=%d\n", ld.Segtext.Filelen+ld.Segdata.Length+uint64(ld.Symsize)+uint64(ld.Lcsize))
}
}