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[dev.link] cmd/link: use new reloc pass on ARM 

Change-Id: I7dde19dbc0b912c4d2446c90364f86e7213add81
Reviewed-on: https://go-review.googlesource.com/c/go/+/232299
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
This commit is contained in:
Cherry Zhang 2020-05-05 00:00:54 -04:00
parent 9f80d91b13
commit afbf9d47dd
3 changed files with 30 additions and 44 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

70
src/cmd/link/internal/arm/asm.go
View File

@ -522,72 +522,58 @@ func gentrampdyn(arch *sys.Arch, tramp *loader.SymbolBuilder, target loader.Sym,
tramp.AddReloc(r)
}
func archreloc(target *ld.Target, syms *ld.ArchSyms, r *sym.Reloc, s *sym.Symbol, val int64) (int64, bool) {
func archreloc2(target *ld.Target, ldr *loader.Loader, syms *ld.ArchSyms, r loader.Reloc2, rr *loader.ExtReloc, s loader.Sym, val int64) (o int64, needExtReloc bool, ok bool) {
rs := r.Sym()
rs = ldr.ResolveABIAlias(rs)
if target.IsExternal() {
switch r.Type {
switch r.Type() {
case objabi.R_CALLARM:
r.Done = false
// set up addend for eventual relocation via outer symbol.
rs := r.Sym
r.Xadd = int64(signext24(r.Add & 0xffffff))
r.Xadd *= 4
if rs.Outer != nil {
r.Xadd += ld.Symaddr(rs) - ld.Symaddr(rs.Outer)
rs = rs.Outer
rs, off := ld.FoldSubSymbolOffset(ldr, rs)
rr.Xadd = int64(signext24(r.Add() & 0xffffff))
rr.Xadd *= 4
rr.Xadd += off
rst := ldr.SymType(rs)
if rst != sym.SHOSTOBJ && rst != sym.SDYNIMPORT && rst != sym.SUNDEFEXT && ldr.SymSect(rs) == nil {
ldr.Errorf(s, "missing section for %s", ldr.SymName(rs))
}
if rs.Type != sym.SHOSTOBJ && rs.Type != sym.SDYNIMPORT && rs.Type != sym.SUNDEFEXT && rs.Sect == nil {
ld.Errorf(s, "missing section for %s", rs.Name)
}
r.Xsym = rs
rr.Xsym = rs
// ld64 for arm seems to want the symbol table to contain offset
// into the section rather than pseudo virtual address that contains
// the section load address.
// we need to compensate that by removing the instruction's address
// from addend.
if target.IsDarwin() {
r.Xadd -= ld.Symaddr(s) + int64(r.Off)
if rr.Xadd/4 > 0x7fffff || rr.Xadd/4 < -0x800000 {
ldr.Errorf(s, "direct call too far %d", rr.Xadd/4)
}
if r.Xadd/4 > 0x7fffff || r.Xadd/4 < -0x800000 {
ld.Errorf(s, "direct call too far %d", r.Xadd/4)
}
return int64(braddoff(int32(0xff000000&uint32(r.Add)), int32(0xffffff&uint32(r.Xadd/4)))), true
return int64(braddoff(int32(0xff000000&uint32(r.Add())), int32(0xffffff&uint32(rr.Xadd/4)))), true, true
}
return -1, false
return -1, false, false
}
switch r.Type {
case objabi.R_CONST:
return r.Add, true
case objabi.R_GOTOFF:
return ld.Symaddr(r.Sym) + r.Add - ld.Symaddr(syms.GOT), true
const isOk = true
const noExtReloc = false
switch r.Type() {
// The following three arch specific relocations are only for generation of
// Linux/ARM ELF's PLT entry (3 assembler instruction)
case objabi.R_PLT0: // add ip, pc, #0xXX00000
if ld.Symaddr(syms.GOTPLT) < ld.Symaddr(syms.PLT) {
ld.Errorf(s, ".got.plt should be placed after .plt section.")
if ldr.SymValue(syms.GOTPLT2) < ldr.SymValue(syms.PLT2) {
ldr.Errorf(s, ".got.plt should be placed after .plt section.")
}
return 0xe28fc600 + (0xff & (int64(uint32(ld.Symaddr(r.Sym)-(ld.Symaddr(syms.PLT)+int64(r.Off))+r.Add)) >> 20)), true
return 0xe28fc600 + (0xff & (int64(uint32(ldr.SymValue(rs)-(ldr.SymValue(syms.PLT2)+int64(r.Off()))+r.Add())) >> 20)), noExtReloc, isOk
case objabi.R_PLT1: // add ip, ip, #0xYY000
return 0xe28cca00 + (0xff & (int64(uint32(ld.Symaddr(r.Sym)-(ld.Symaddr(syms.PLT)+int64(r.Off))+r.Add+4)) >> 12)), true
return 0xe28cca00 + (0xff & (int64(uint32(ldr.SymValue(rs)-(ldr.SymValue(syms.PLT2)+int64(r.Off()))+r.Add()+4)) >> 12)), noExtReloc, isOk
case objabi.R_PLT2: // ldr pc, [ip, #0xZZZ]!
return 0xe5bcf000 + (0xfff & int64(uint32(ld.Symaddr(r.Sym)-(ld.Symaddr(syms.PLT)+int64(r.Off))+r.Add+8))), true
return 0xe5bcf000 + (0xfff & int64(uint32(ldr.SymValue(rs)-(ldr.SymValue(syms.PLT2)+int64(r.Off()))+r.Add()+8))), noExtReloc, isOk
case objabi.R_CALLARM: // bl XXXXXX or b YYYYYY
// r.Add is the instruction
// low 24-bit encodes the target address
t := (ld.Symaddr(r.Sym) + int64(signext24(r.Add&0xffffff)*4) - (s.Value + int64(r.Off))) / 4
t := (ldr.SymValue(rs) + int64(signext24(r.Add()&0xffffff)*4) - (ldr.SymValue(s) + int64(r.Off()))) / 4
if t > 0x7fffff || t < -0x800000 {
ld.Errorf(s, "direct call too far: %s %x", r.Sym.Name, t)
ldr.Errorf(s, "direct call too far: %s %x", ldr.SymName(rs), t)
}
return int64(braddoff(int32(0xff000000&uint32(r.Add)), int32(0xffffff&t))), true
return int64(braddoff(int32(0xff000000&uint32(r.Add())), int32(0xffffff&t))), noExtReloc, isOk
}
return val, false
return val, false, false
}
func archrelocvariant(target *ld.Target, syms *ld.ArchSyms, r *sym.Reloc, s *sym.Symbol, t int64) int64 {

2
src/cmd/link/internal/arm/obj.go
View File

@ -48,7 +48,7 @@ func Init() (*sys.Arch, ld.Arch) {
Adddynrel2: adddynrel2,
Archinit: archinit,
Archreloc: archreloc,
Archreloc2: archreloc2,
Archrelocvariant: archrelocvariant,
Trampoline: trampoline,
Asmb: asmb,

2
src/cmd/link/internal/ld/main.go
View File

@ -319,7 +319,7 @@ func Main(arch *sys.Arch, theArch Arch) {
ctxt.loader.InitOutData()
thearch.Asmb(ctxt, ctxt.loader)
newreloc := ctxt.Is386() || ctxt.IsAMD64() || ctxt.IsMIPS() || ctxt.IsMIPS64() || ctxt.IsRISCV64() || ctxt.IsS390X() || ctxt.IsWasm()
newreloc := ctxt.Is386() || ctxt.IsAMD64() || ctxt.IsARM() || ctxt.IsMIPS() || ctxt.IsMIPS64() || ctxt.IsRISCV64() || ctxt.IsS390X() || ctxt.IsWasm()
if newreloc {
bench.Start("reloc")
ctxt.reloc()