cmd/link: support cgo internal/linking on darwin/arm64
Cgo programs work as well. Still not enabled by default for now.
Enable internal linking tests.
Updates #38485.
Change-Id: I8324a5c263fba221eb4e67d71207ca84fa241e6c
Reviewed-on: https://go-review.googlesource.com/c/go/+/263637
Trust: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
diff --git a/misc/cgo/test/issue4029.c b/misc/cgo/test/issue4029.c
index e6a777f..e79c5a7 100644
--- a/misc/cgo/test/issue4029.c
+++ b/misc/cgo/test/issue4029.c
@@ -3,7 +3,7 @@
// license that can be found in the LICENSE file.
// +build !windows,!static
-// +build !darwin !internal_pie
+// +build !darwin !internal_pie,!arm64
#include <stdint.h>
#include <dlfcn.h>
diff --git a/misc/cgo/test/issue4029.go b/misc/cgo/test/issue4029.go
index 8602ce19..b2d1318 100644
--- a/misc/cgo/test/issue4029.go
+++ b/misc/cgo/test/issue4029.go
@@ -3,10 +3,11 @@
// license that can be found in the LICENSE file.
// +build !windows,!static
-// +build !darwin !internal_pie
+// +build !darwin !internal_pie,!arm64
// Excluded in darwin internal linking PIE mode, as dynamic export is not
// supported.
+// Excluded in internal linking mode on darwin/arm64, as it is always PIE.
package cgotest
diff --git a/misc/cgo/test/issue4029w.go b/misc/cgo/test/issue4029w.go
index de0cf21..b969bdd 100644
--- a/misc/cgo/test/issue4029w.go
+++ b/misc/cgo/test/issue4029w.go
@@ -2,7 +2,7 @@
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
-// +build windows static darwin,internal_pie
+// +build windows static darwin,internal_pie darwin,arm64
package cgotest
diff --git a/src/cmd/dist/test.go b/src/cmd/dist/test.go
index bcb12f2..09d69f7 100644
--- a/src/cmd/dist/test.go
+++ b/src/cmd/dist/test.go
@@ -946,9 +946,6 @@
if goos == "ios" {
return false
}
- if goos == "darwin" && goarch == "arm64" {
- return false
- }
// Internally linking cgo is incomplete on some architectures.
// https://golang.org/issue/10373
// https://golang.org/issue/14449
@@ -964,7 +961,7 @@
func (t *tester) internalLinkPIE() bool {
switch goos + "-" + goarch {
- case "darwin-amd64",
+ case "darwin-amd64", "darwin-arm64",
"linux-amd64", "linux-arm64",
"android-arm64",
"windows-amd64", "windows-386", "windows-arm":
@@ -1088,7 +1085,7 @@
pair := gohostos + "-" + goarch
switch pair {
- case "darwin-amd64",
+ case "darwin-amd64", "darwin-arm64",
"openbsd-386", "openbsd-amd64",
"windows-386", "windows-amd64":
// test linkmode=external, but __thread not supported, so skip testtls.
diff --git a/src/cmd/link/internal/arm64/asm.go b/src/cmd/link/internal/arm64/asm.go
index 585c968..e456411 100644
--- a/src/cmd/link/internal/arm64/asm.go
+++ b/src/cmd/link/internal/arm64/asm.go
@@ -71,13 +71,13 @@
}
func adddynrel(target *ld.Target, ldr *loader.Loader, syms *ld.ArchSyms, s loader.Sym, r loader.Reloc, rIdx int) bool {
-
targ := r.Sym()
var targType sym.SymKind
if targ != 0 {
targType = ldr.SymType(targ)
}
+ const pcrel = 1
switch r.Type() {
default:
if r.Type() >= objabi.ElfRelocOffset {
@@ -201,6 +201,75 @@
su := ldr.MakeSymbolUpdater(s)
su.SetRelocType(rIdx, objabi.R_ARM64_LDST128)
return true
+
+ // Handle relocations found in Mach-O object files.
+ case objabi.MachoRelocOffset + ld.MACHO_ARM64_RELOC_UNSIGNED*2:
+ if targType == sym.SDYNIMPORT {
+ ldr.Errorf(s, "unexpected reloc for dynamic symbol %s", ldr.SymName(targ))
+ }
+ su := ldr.MakeSymbolUpdater(s)
+ su.SetRelocType(rIdx, objabi.R_ADDR)
+ if target.IsPIE() && target.IsInternal() {
+ // For internal linking PIE, this R_ADDR relocation cannot
+ // be resolved statically. We need to generate a dynamic
+ // relocation. Let the code below handle it.
+ break
+ }
+ return true
+
+ case objabi.MachoRelocOffset + ld.MACHO_ARM64_RELOC_BRANCH26*2 + pcrel:
+ su := ldr.MakeSymbolUpdater(s)
+ su.SetRelocType(rIdx, objabi.R_CALLARM64)
+ if targType == sym.SDYNIMPORT {
+ addpltsym(target, ldr, syms, targ)
+ su.SetRelocSym(rIdx, syms.PLT)
+ su.SetRelocAdd(rIdx, int64(ldr.SymPlt(targ)))
+ }
+ return true
+
+ case objabi.MachoRelocOffset + ld.MACHO_ARM64_RELOC_PAGE21*2 + pcrel,
+ objabi.MachoRelocOffset + ld.MACHO_ARM64_RELOC_PAGEOFF12*2:
+ if targType == sym.SDYNIMPORT {
+ ldr.Errorf(s, "unexpected relocation for dynamic symbol %s", ldr.SymName(targ))
+ }
+ su := ldr.MakeSymbolUpdater(s)
+ su.SetRelocType(rIdx, objabi.R_ARM64_PCREL)
+ return true
+
+ case objabi.MachoRelocOffset + ld.MACHO_ARM64_RELOC_GOT_LOAD_PAGE21*2 + pcrel,
+ objabi.MachoRelocOffset + ld.MACHO_ARM64_RELOC_GOT_LOAD_PAGEOFF12*2:
+ if targType != sym.SDYNIMPORT {
+ // have symbol
+ // turn MOVD sym@GOT (adrp+ldr) into MOVD $sym (adrp+add)
+ data := ldr.Data(s)
+ off := r.Off()
+ if int(off+3) >= len(data) {
+ ldr.Errorf(s, "unexpected GOT_LOAD reloc for non-dynamic symbol %s", ldr.SymName(targ))
+ return false
+ }
+ o := target.Arch.ByteOrder.Uint32(data[off:])
+ su := ldr.MakeSymbolUpdater(s)
+ switch {
+ case (o>>24)&0x9f == 0x90: // adrp
+ // keep instruction unchanged, change relocation type below
+ case o>>24 == 0xf9: // ldr
+ // rewrite to add
+ o = (0x91 << 24) | (o & (1<<22 - 1))
+ su.MakeWritable()
+ su.SetUint32(target.Arch, int64(off), o)
+ default:
+ ldr.Errorf(s, "unexpected GOT_LOAD reloc for non-dynamic symbol %s", ldr.SymName(targ))
+ return false
+ }
+ su.SetRelocType(rIdx, objabi.R_ARM64_PCREL)
+ return true
+ }
+ ld.AddGotSym(target, ldr, syms, targ, 0)
+ su := ldr.MakeSymbolUpdater(s)
+ su.SetRelocType(rIdx, objabi.R_ARM64_GOT)
+ su.SetRelocSym(rIdx, syms.GOT)
+ su.SetRelocAdd(rIdx, int64(ldr.SymGot(targ)))
+ return true
}
// Reread the reloc to incorporate any changes in type above.
@@ -671,14 +740,28 @@
}
o0 := (uint32((t>>12)&3) << 29) | (uint32((t>>12>>2)&0x7ffff) << 5)
return val | int64(o0), noExtReloc, isOk
- } else if (val>>24)&0x91 == 0x91 {
- // R_AARCH64_ADD_ABS_LO12_NC
+ } else if (val>>24)&0x9f == 0x91 {
+ // ELF R_AARCH64_ADD_ABS_LO12_NC or Mach-O ARM64_RELOC_PAGEOFF12
// patch instruction: add
t := ldr.SymAddr(rs) + r.Add() - ((ldr.SymValue(s) + int64(r.Off())) &^ 0xfff)
o1 := uint32(t&0xfff) << 10
return val | int64(o1), noExtReloc, isOk
+ } else if (val>>24)&0x3b == 0x39 {
+ // Mach-O ARM64_RELOC_PAGEOFF12
+ // patch ldr/str(b/h/w/d/q) (integer or vector) instructions, which have different scaling factors.
+ // Mach-O uses same relocation type for them.
+ shift := uint32(val) >> 30
+ if shift == 0 && (val>>20)&0x048 == 0x048 { // 128-bit vector load
+ shift = 4
+ }
+ t := ldr.SymAddr(rs) + r.Add() - ((ldr.SymValue(s) + int64(r.Off())) &^ 0xfff)
+ if t&(1<<shift-1) != 0 {
+ ldr.Errorf(s, "invalid address: %x for relocation type: ARM64_RELOC_PAGEOFF12", t)
+ }
+ o1 := (uint32(t&0xfff) >> shift) << 10
+ return val | int64(o1), noExtReloc, isOk
} else {
- ldr.Errorf(s, "unsupported instruction for %x R_PCRELARM64", val)
+ ldr.Errorf(s, "unsupported instruction for %x R_ARM64_PCREL", val)
}
case objabi.R_ARM64_LDST8:
diff --git a/src/cmd/link/internal/ld/config.go b/src/cmd/link/internal/ld/config.go
index 834c87d..a54b96d 100644
--- a/src/cmd/link/internal/ld/config.go
+++ b/src/cmd/link/internal/ld/config.go
@@ -208,9 +208,6 @@
if iscgo && objabi.GOOS == "android" {
return true, objabi.GOOS + " does not support internal cgo"
}
- if iscgo && objabi.GOOS == "darwin" && objabi.GOARCH == "arm64" {
- return true, objabi.GOOS + "/" + objabi.GOARCH + " does not support internal cgo"
- }
// When the race flag is set, the LLVM tsan relocatable file is linked
// into the final binary, which means external linking is required because
diff --git a/src/cmd/link/internal/loader/loader.go b/src/cmd/link/internal/loader/loader.go
index 47cac04..d861efc 100644
--- a/src/cmd/link/internal/loader/loader.go
+++ b/src/cmd/link/internal/loader/loader.go
@@ -2622,11 +2622,15 @@
fmt.Println("Nsyms:", len(l.objSyms))
fmt.Println("syms")
for i := Sym(1); i < Sym(len(l.objSyms)); i++ {
- pi := interface{}("")
+ pi := ""
if l.IsExternal(i) {
pi = fmt.Sprintf("<ext %d>", l.extIndex(i))
}
- fmt.Println(i, l.SymName(i), l.SymType(i), pi)
+ sect := ""
+ if l.SymSect(i) != nil {
+ sect = l.SymSect(i).Name
+ }
+ fmt.Printf("%v %v %v %v %x %v\n", i, l.SymName(i), l.SymType(i), pi, l.SymValue(i), sect)
}
fmt.Println("symsByName")
for name, i := range l.symsByName[0] {
diff --git a/src/cmd/link/internal/loadmacho/ldmacho.go b/src/cmd/link/internal/loadmacho/ldmacho.go
index 864d808..d12f2bc 100644
--- a/src/cmd/link/internal/loadmacho/ldmacho.go
+++ b/src/cmd/link/internal/loadmacho/ldmacho.go
@@ -43,7 +43,7 @@
THE SOFTWARE.
*/
-// TODO(crawshaw): de-duplicate these symbols with cmd/internal/ld
+// TODO(crawshaw): de-duplicate these symbols with cmd/link/internal/ld
const (
MACHO_X86_64_RELOC_UNSIGNED = 0
MACHO_X86_64_RELOC_SIGNED = 1
@@ -172,11 +172,12 @@
LdMachoCpuVax = 1
LdMachoCpu68000 = 6
LdMachoCpu386 = 7
- LdMachoCpuAmd64 = 0x1000007
+ LdMachoCpuAmd64 = 1<<24 | 7
LdMachoCpuMips = 8
LdMachoCpu98000 = 10
LdMachoCpuHppa = 11
LdMachoCpuArm = 12
+ LdMachoCpuArm64 = 1<<24 | 12
LdMachoCpu88000 = 13
LdMachoCpuSparc = 14
LdMachoCpu860 = 15
@@ -471,11 +472,14 @@
switch arch.Family {
default:
return errorf("mach-o %s unimplemented", arch.Name)
-
case sys.AMD64:
if e != binary.LittleEndian || m.cputype != LdMachoCpuAmd64 {
return errorf("mach-o object but not amd64")
}
+ case sys.ARM64:
+ if e != binary.LittleEndian || m.cputype != LdMachoCpuArm64 {
+ return errorf("mach-o object but not arm64")
+ }
}
m.cmd = make([]ldMachoCmd, ncmd)
@@ -633,7 +637,9 @@
}
bld.SetType(l.SymType(outer))
- l.AddInteriorSym(outer, s)
+ if l.SymSize(outer) != 0 { // skip empty section (0-sized symbol)
+ l.AddInteriorSym(outer, s)
+ }
bld.SetValue(int64(machsym.value - sect.addr))
if !l.AttrCgoExportDynamic(s) {
@@ -722,27 +728,28 @@
// Handle X86_64_RELOC_SIGNED referencing a section (rel.extrn == 0).
p := l.Data(s)
- if arch.Family == sys.AMD64 && rel.extrn == 0 && rel.type_ == MACHO_X86_64_RELOC_SIGNED {
- // Calculate the addend as the offset into the section.
- //
- // The rip-relative offset stored in the object file is encoded
- // as follows:
- //
- // movsd 0x00000360(%rip),%xmm0
- //
- // To get the absolute address of the value this rip-relative address is pointing
- // to, we must add the address of the next instruction to it. This is done by
- // taking the address of the relocation and adding 4 to it (since the rip-relative
- // offset can at most be 32 bits long). To calculate the offset into the section the
- // relocation is referencing, we subtract the vaddr of the start of the referenced
- // section found in the original object file.
- //
- // [For future reference, see Darwin's /usr/include/mach-o/x86_64/reloc.h]
- secaddr := c.seg.sect[rel.symnum-1].addr
-
- rAdd = int64(uint64(int64(int32(e.Uint32(p[rOff:])))+int64(rOff)+4) - secaddr)
- } else {
- rAdd = int64(int32(e.Uint32(p[rOff:])))
+ if arch.Family == sys.AMD64 {
+ if rel.extrn == 0 && rel.type_ == MACHO_X86_64_RELOC_SIGNED {
+ // Calculate the addend as the offset into the section.
+ //
+ // The rip-relative offset stored in the object file is encoded
+ // as follows:
+ //
+ // movsd 0x00000360(%rip),%xmm0
+ //
+ // To get the absolute address of the value this rip-relative address is pointing
+ // to, we must add the address of the next instruction to it. This is done by
+ // taking the address of the relocation and adding 4 to it (since the rip-relative
+ // offset can at most be 32 bits long). To calculate the offset into the section the
+ // relocation is referencing, we subtract the vaddr of the start of the referenced
+ // section found in the original object file.
+ //
+ // [For future reference, see Darwin's /usr/include/mach-o/x86_64/reloc.h]
+ secaddr := c.seg.sect[rel.symnum-1].addr
+ rAdd = int64(uint64(int64(int32(e.Uint32(p[rOff:])))+int64(rOff)+4) - secaddr)
+ } else {
+ rAdd = int64(int32(e.Uint32(p[rOff:])))
+ }
}
// An unsigned internal relocation has a value offset
