[dev.link] cmd/link: move asmb2 plan 9 architecture code out of architectures

Change-Id: I7a8f8edc4511e3ae0c44ec5017167f14d4c60755
Reviewed-on: https://go-review.googlesource.com/c/go/+/234891
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>

src/cmd/link/internal/amd64/asm.go

@@ -679,41 +679,6 @@ func addgotsym(target *ld.Target, ldr *loader.Loader, syms *ld.ArchSyms, s loade
 	}
 }
 
-func asmb2(ctxt *ld.Link, _ *loader.Loader) {
-	if ctxt.IsDarwin() {
-		panic("darwin should be generic")
-	}
-	if ctxt.IsElf() {
-		panic("elf should be generic")
-	}
-	if ctxt.IsWindows() {
-		panic("pe should be generic")
-	}
-
-	switch ctxt.HeadType {
-	default:
-		ld.Errorf(nil, "unknown header type %v", ctxt.HeadType)
-		fallthrough
-
-	case objabi.Hplan9:
-		break
-	}
-
-	ld.Symsize = 0
-	ld.Spsize = 0
-	ld.Lcsize = 0
-	if !*ld.FlagS {
-		*ld.FlagS = true
-		symo := int64(ld.Segdata.Fileoff + ld.Segdata.Filelen)
-		ctxt.Out.SeekSet(symo)
-		ld.Asmplan9sym(ctxt)
-	}
-
-	ctxt.Out.SeekSet(0)
-	magic := uint32(4*26*26 + 7)
-	ld.WritePlan9Header(ctxt.Out, magic, ld.Entryvalue(ctxt), true)
-}
-
 func tlsIEtoLE(P []byte, off, size int) {
 	// Transform the PC-relative instruction into a constant load.
 	// That is,

src/cmd/link/internal/amd64/obj.go

@@ -53,11 +53,13 @@ func Init() (*sys.Arch, ld.Arch) {
 		// 0xCC is INT $3 - breakpoint instruction
 		CodePad: []byte{0xCC},
 
+		Plan9Magic:  uint32(4*26*26 + 7),
+		Plan9_64Bit: true,
+
 		Adddynrel:        adddynrel,
 		Archinit:         archinit,
 		Archreloc:        archreloc,
 		Archrelocvariant: archrelocvariant,
-		Asmb2:            asmb2,
 		Elfreloc1:        elfreloc1,
 		Elfsetupplt:      elfsetupplt,
 		Gentext:          gentext,

src/cmd/link/internal/arm/asm.go

@@ -670,32 +670,3 @@ func addgotsym(target *ld.Target, ldr *loader.Loader, syms *ld.ArchSyms, s loade
 		ldr.Errorf(s, "addgotsym: unsupported binary format")
 	}
 }
-
-func asmb2(ctxt *ld.Link, _ *loader.Loader) {
-	if ctxt.IsElf() {
-		panic("elf should be generic")
-	}
-	if ctxt.IsWindows() {
-		panic("pe should be generic")
-	}
-	/* output symbol table */
-	ld.Symsize = 0
-
-	ld.Lcsize = 0
-	if !*ld.FlagS {
-		symo := uint32(ld.Segdata.Fileoff + ld.Segdata.Filelen)
-		ctxt.Out.SeekSet(int64(symo))
-		ld.Asmplan9sym(ctxt)
-	}
-
-	ld.WritePlan9Header(ctxt.Out, 0x647, ld.Entryvalue(ctxt), false)
-
-	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))
-	}
-}

src/cmd/link/internal/arm/obj.go

@@ -46,12 +46,13 @@ func Init() (*sys.Arch, ld.Arch) {
 		Dwarfregsp: dwarfRegSP,
 		Dwarfreglr: dwarfRegLR,
 
+		Plan9Magic: 0x647,
+
 		Adddynrel:        adddynrel,
 		Archinit:         archinit,
 		Archreloc:        archreloc,
 		Archrelocvariant: archrelocvariant,
 		Trampoline:       trampoline,
-		Asmb2:            asmb2,
 		Elfreloc1:        elfreloc1,
 		Elfsetupplt:      elfsetupplt,
 		Gentext:          gentext,

src/cmd/link/internal/ld/asmb.go

@@ -6,6 +6,7 @@ package ld
 
 import (
 	"cmd/link/internal/loader"
+	"fmt"
 	"sync"
 )
 
@@ -74,12 +75,16 @@ func asmb(ctxt *Link, ldr *loader.Loader) {
 //  - writing out the architecture specific pieces.
 // This function handles the second part.
 func asmb2(ctxt *Link) bool {
-	// TODO: Spsize is only used for plan9
+	if ctxt.IsAIX() || ctxt.IsWasm() {
+		return false
+	}
+
+	Symsize = 0
+	Spsize = 0
+	Lcsize = 0
+
 	if ctxt.IsDarwin() {
 		machlink := Domacholink(ctxt)
-		Symsize = 0
-		Spsize = 0
-		Lcsize = 0
 		if !*FlagS && ctxt.IsExternal() {
 			symo := int64(Segdwarf.Fileoff + uint64(Rnd(int64(Segdwarf.Filelen), int64(*FlagRound))) + uint64(machlink))
 			ctxt.Out.SeekSet(symo)
@@ -87,12 +92,9 @@ func asmb2(ctxt *Link) bool {
 		}
 		ctxt.Out.SeekSet(0)
 		Asmbmacho(ctxt)
-		return true
 	}
+
 	if ctxt.IsElf() {
-		Symsize = 0
-		Spsize = 0
-		Lcsize = 0
 		var symo int64
 		if !*FlagS {
 			symo = int64(Segdwarf.Fileoff + Segdwarf.Filelen)
@@ -106,16 +108,33 @@ func asmb2(ctxt *Link) bool {
 		}
 		ctxt.Out.SeekSet(0)
 		Asmbelf(ctxt, symo)
-		return true
 	}
+
 	if ctxt.IsWindows() {
-		Symsize = 0
-		Spsize = 0
-		Lcsize = 0
 		Asmbpe(ctxt)
-		return true
 	}
-	return false
+
+	if ctxt.IsPlan9() {
+		if !*FlagS {
+			*FlagS = true
+			symo := int64(Segdata.Fileoff + Segdata.Filelen)
+			ctxt.Out.SeekSet(symo)
+			Asmplan9sym(ctxt)
+		}
+		ctxt.Out.SeekSet(0)
+		WritePlan9Header(ctxt.Out, thearch.Plan9Magic, Entryvalue(ctxt), thearch.Plan9_64Bit)
+	}
+
+	if *FlagC {
+		fmt.Printf("textsize=%d\n", Segtext.Filelen)
+		fmt.Printf("datsize=%d\n", Segdata.Filelen)
+		fmt.Printf("bsssize=%d\n", Segdata.Length-Segdata.Filelen)
+		fmt.Printf("symsize=%d\n", Symsize)
+		fmt.Printf("lcsize=%d\n", Lcsize)
+		fmt.Printf("total=%d\n", Segtext.Filelen+Segdata.Length+uint64(Symsize)+uint64(Lcsize))
+	}
+
+	return true
 }
 
 // WritePlan9Header writes out the plan9 header at the present position in the OutBuf.

src/cmd/link/internal/ld/lib.go

@@ -195,6 +195,10 @@ type Arch struct {
 	// Set to true to write all text blocks in with CodeBlkWrite
 	WriteTextBlocks bool
 
+	// Plan 9 variables.
+	Plan9Magic  uint32
+	Plan9_64Bit bool
+
 	Adddynrel func(*Target, *loader.Loader, *ArchSyms, loader.Sym, loader.Reloc2, int) bool
 	Archinit  func(*Link)
 	// Archreloc is an arch-specific hook that assists in relocation processing

src/cmd/link/internal/x86/asm.go

@@ -509,28 +509,3 @@ func addgotsym(target *ld.Target, ldr *loader.Loader, syms *ld.ArchSyms, s loade
 		ldr.Errorf(s, "addgotsym: unsupported binary format")
 	}
 }
-
-func asmb2(ctxt *ld.Link, _ *loader.Loader) {
-	if ctxt.IsDarwin() {
-		panic("darwin should be generic")
-	}
-	if ctxt.IsElf() {
-		panic("elf should be generic")
-	}
-	if ctxt.IsWindows() {
-		panic("pe should be generic")
-	}
-
-	ld.Symsize = 0
-	ld.Spsize = 0
-	ld.Lcsize = 0
-	if !*ld.FlagS {
-		symo := uint32(ld.Segdata.Fileoff + ld.Segdata.Filelen)
-		ctxt.Out.SeekSet(int64(symo))
-		ld.Asmplan9sym(ctxt)
-	}
-
-	ctxt.Out.SeekSet(0)
-	magic := uint32(4*11*11 + 7)
-	ld.WritePlan9Header(ctxt.Out, magic, ld.Entryvalue(ctxt), false)
-}

src/cmd/link/internal/x86/obj.go

@@ -48,11 +48,12 @@ func Init() (*sys.Arch, ld.Arch) {
 		// 0xCC is INT $3 - breakpoint instruction
 		CodePad: []byte{0xCC},
 
+		Plan9Magic: uint32(4*11*11 + 7),
+
 		Adddynrel:        adddynrel,
 		Archinit:         archinit,
 		Archreloc:        archreloc,
 		Archrelocvariant: archrelocvariant,
-		Asmb2:            asmb2,
 		Elfreloc1:        elfreloc1,
 		Elfsetupplt:      elfsetupplt,
 		Gentext:          gentext,