cmd/internal/obj: eagerly initialize assemblers

CL 38662 changed the x86 assembler to be eagerly
initialized, for a concurrent backend.

This CL puts in place a proper mechanism for doing so,
and switches all architectures to use it.

Passes toolstash-check -all.

Updates #15756

Change-Id: Id2aa527d3a8259c95797d63a2f0d1123e3ca2a1c
Reviewed-on: https://go-review.googlesource.com/39917
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

src/cmd/asm/internal/arch/arch.go

@@ -171,8 +171,6 @@ func archX86(linkArch *obj.LinkArch) *Arch {
 	instructions["PSRLDQ"] = x86.APSRLO
 	instructions["PADDD"] = x86.APADDL
 
-	x86.InstInit()
-
 	return &Arch{
 		LinkArch:       linkArch,
 		Instructions:   instructions,

src/cmd/asm/internal/asm/endtoend_test.go

@@ -28,6 +28,7 @@ import (
 func testEndToEnd(t *testing.T, goarch, file string) {
 	input := filepath.Join("testdata", file+".s")
 	architecture, ctxt := setArch(goarch)
+	architecture.Init(ctxt)
 	lexer := lex.NewLexer(input)
 	parser := NewParser(ctxt, architecture, lexer)
 	pList := new(obj.Plist)

src/cmd/asm/main.go

@@ -42,6 +42,8 @@ func main() {
 	ctxt.Bso = bufio.NewWriter(os.Stdout)
 	defer ctxt.Bso.Flush()
 
+	architecture.Init(ctxt)
+
 	// Create object file, write header.
 	out, err := os.Create(*flags.OutputFile)
 	if err != nil {

src/cmd/compile/internal/amd64/galign.go

@@ -27,6 +27,4 @@ func Init(arch *gc.Arch) {
 	arch.SSAMarkMoves = ssaMarkMoves
 	arch.SSAGenValue = ssaGenValue
 	arch.SSAGenBlock = ssaGenBlock
-
-	x86.InstInit()
 }

src/cmd/compile/internal/gc/main.go

@@ -238,6 +238,8 @@ func Main(archInit func(*Arch)) {
 		usage()
 	}
 
+	thearch.LinkArch.Init(Ctxt)
+
 	if outfile == "" {
 		p := flag.Arg(0)
 		if i := strings.LastIndex(p, "/"); i >= 0 {

src/cmd/compile/internal/x86/galign.go

@@ -33,6 +33,4 @@ func Init(arch *gc.Arch) {
 	arch.Ginsnop = ginsnop
 
 	arch.SSAMarkMoves = ssaMarkMoves
-
-	x86.InstInit()
 }

src/cmd/internal/obj/arm/asm5.go

@@ -557,7 +557,7 @@ func span5(ctxt *obj.Link, cursym *obj.LSym, newprog obj.ProgAlloc) {
 	}
 
 	if oprange[AAND&obj.AMask] == nil {
-		buildop(ctxt)
+		ctxt.Diag("arm ops not initialized, call arm.buildop first")
 	}
 
 	ctxt.Cursym = cursym
@@ -1296,6 +1296,13 @@ func opset(a, b0 obj.As) {
 }
 
 func buildop(ctxt *obj.Link) {
+	if oprange[AAND&obj.AMask] != nil {
+		// Already initialized; stop now.
+		// This happens in the cmd/asm tests,
+		// each of which re-initializes the arch.
+		return
+	}
+
 	var n int
 
 	for i := 0; i < C_GOK; i++ {

src/cmd/internal/obj/arm/obj5.go

@@ -880,6 +880,7 @@ var unaryDst = map[obj.As]bool{
 
 var Linkarm = obj.LinkArch{
 	Arch:       sys.ArchARM,
+	Init:       buildop,
 	Preprocess: preprocess,
 	Assemble:   span5,
 	Progedit:   progedit,

src/cmd/internal/obj/arm64/asm7.go

@@ -537,7 +537,7 @@ func span7(ctxt *obj.Link, cursym *obj.LSym, newprog obj.ProgAlloc) {
 	ctxt.Autosize = int32(p.To.Offset&0xffffffff) + 8
 
 	if oprange[AAND&obj.AMask] == nil {
-		buildop(ctxt)
+		ctxt.Diag("arm64 ops not initialized, call arm64.buildop first")
 	}
 
 	bflag := 1
@@ -1438,6 +1438,13 @@ func oprangeset(a obj.As, t []Optab) {
 }
 
 func buildop(ctxt *obj.Link) {
+	if oprange[AAND&obj.AMask] != nil {
+		// Already initialized; stop now.
+		// This happens in the cmd/asm tests,
+		// each of which re-initializes the arch.
+		return
+	}
+
 	var n int
 	for i := 0; i < C_GOK; i++ {
 		for n = 0; n < C_GOK; n++ {

src/cmd/internal/obj/arm64/obj7.go

@@ -799,6 +799,7 @@ var unaryDst = map[obj.As]bool{
 
 var Linkarm64 = obj.LinkArch{
 	Arch:       sys.ArchARM64,
+	Init:       buildop,
 	Preprocess: preprocess,
 	Assemble:   span7,
 	Progedit:   progedit,

src/cmd/internal/obj/link.go

@@ -786,6 +786,7 @@ type SymVer struct {
 // LinkArch is the definition of a single architecture.
 type LinkArch struct {
 	*sys.Arch
+	Init       func(*Link)
 	Preprocess func(*Link, *LSym, ProgAlloc)
 	Assemble   func(*Link, *LSym, ProgAlloc)
 	Progedit   func(*Link, *Prog, ProgAlloc)

src/cmd/internal/obj/mips/asm0.go

@@ -382,7 +382,7 @@ func span0(ctxt *obj.Link, cursym *obj.LSym, newprog obj.ProgAlloc) {
 	ctxt.Autosize = int32(p.To.Offset + ctxt.FixedFrameSize())
 
 	if oprange[AOR&obj.AMask] == nil {
-		buildop(ctxt)
+		ctxt.Diag("mips ops not initialized, call mips.buildop first")
 	}
 
 	c := int64(0)
@@ -668,7 +668,7 @@ func prasm(p *obj.Prog) {
 
 func oplook(ctxt *obj.Link, p *obj.Prog) *Optab {
 	if oprange[AOR&obj.AMask] == nil {
-		buildop(ctxt)
+		ctxt.Diag("mips ops not initialized, call mips.buildop first")
 	}
 
 	a1 := int(p.Optab)
@@ -833,6 +833,13 @@ func opset(a, b0 obj.As) {
 }
 
 func buildop(ctxt *obj.Link) {
+	if oprange[AOR&obj.AMask] != nil {
+		// Already initialized; stop now.
+		// This happens in the cmd/asm tests,
+		// each of which re-initializes the arch.
+		return
+	}
+
 	var n int
 
 	for i := 0; i < C_NCLASS; i++ {

src/cmd/internal/obj/mips/obj0.go

@@ -1398,6 +1398,7 @@ func compound(ctxt *obj.Link, p *obj.Prog) bool {
 
 var Linkmips64 = obj.LinkArch{
 	Arch:       sys.ArchMIPS64,
+	Init:       buildop,
 	Preprocess: preprocess,
 	Assemble:   span0,
 	Progedit:   progedit,
@@ -1405,6 +1406,7 @@ var Linkmips64 = obj.LinkArch{
 
 var Linkmips64le = obj.LinkArch{
 	Arch:       sys.ArchMIPS64LE,
+	Init:       buildop,
 	Preprocess: preprocess,
 	Assemble:   span0,
 	Progedit:   progedit,
@@ -1412,6 +1414,7 @@ var Linkmips64le = obj.LinkArch{
 
 var Linkmips = obj.LinkArch{
 	Arch:       sys.ArchMIPS,
+	Init:       buildop,
 	Preprocess: preprocess,
 	Assemble:   span0,
 	Progedit:   progedit,
@@ -1419,6 +1422,7 @@ var Linkmips = obj.LinkArch{
 
 var Linkmipsle = obj.LinkArch{
 	Arch:       sys.ArchMIPSLE,
+	Init:       buildop,
 	Preprocess: preprocess,
 	Assemble:   span0,
 	Progedit:   progedit,

src/cmd/internal/obj/ppc64/asm9.go

@@ -561,7 +561,7 @@ func span9(ctxt *obj.Link, cursym *obj.LSym, newprog obj.ProgAlloc) {
 	ctxt.Autosize = int32(p.To.Offset)
 
 	if oprange[AANDN&obj.AMask] == nil {
-		buildop(ctxt)
+		ctxt.Diag("ppc64 ops not initialized, call ppc64.buildop first")
 	}
 
 	c := int64(0)
@@ -1052,6 +1052,13 @@ func opset(a, b0 obj.As) {
 }
 
 func buildop(ctxt *obj.Link) {
+	if oprange[AANDN&obj.AMask] != nil {
+		// Already initialized; stop now.
+		// This happens in the cmd/asm tests,
+		// each of which re-initializes the arch.
+		return
+	}
+
 	var n int
 
 	for i := 0; i < C_NCLASS; i++ {

src/cmd/internal/obj/ppc64/obj9.go

@@ -1051,6 +1051,7 @@ func stacksplit(ctxt *obj.Link, p *obj.Prog, newprog obj.ProgAlloc, framesize in
 
 var Linkppc64 = obj.LinkArch{
 	Arch:       sys.ArchPPC64,
+	Init:       buildop,
 	Preprocess: preprocess,
 	Assemble:   span9,
 	Progedit:   progedit,
@@ -1058,6 +1059,7 @@ var Linkppc64 = obj.LinkArch{
 
 var Linkppc64le = obj.LinkArch{
 	Arch:       sys.ArchPPC64LE,
+	Init:       buildop,
 	Preprocess: preprocess,
 	Assemble:   span9,
 	Progedit:   progedit,

src/cmd/internal/obj/s390x/asmz.go

@@ -394,7 +394,7 @@ func spanz(ctxt *obj.Link, cursym *obj.LSym, newprog obj.ProgAlloc) {
 	ctxt.Autosize = int32(p.To.Offset)
 
 	if oprange[AORW&obj.AMask] == nil {
-		buildop(ctxt)
+		ctxt.Diag("s390x ops not initialized, call s390x.buildop first")
 	}
 
 	buffer := make([]byte, 0)
@@ -772,6 +772,13 @@ func opset(a, b obj.As) {
 }
 
 func buildop(ctxt *obj.Link) {
+	if oprange[AORW&obj.AMask] != nil {
+		// Already initialized; stop now.
+		// This happens in the cmd/asm tests,
+		// each of which re-initializes the arch.
+		return
+	}
+
 	for i := 0; i < C_NCLASS; i++ {
 		for n := 0; n < C_NCLASS; n++ {
 			if cmp(n, i) {

src/cmd/internal/obj/s390x/objz.go

@@ -715,6 +715,7 @@ var unaryDst = map[obj.As]bool{
 
 var Links390x = obj.LinkArch{
 	Arch:       sys.ArchS390X,
+	Init:       buildop,
 	Preprocess: preprocess,
 	Assemble:   spanz,
 	Progedit:   progedit,

src/cmd/internal/obj/x86/asm6.go

@@ -883,8 +883,8 @@ var ymmxmm0f38 = []ytab{
  * two values match the Ytypes of the p->from and p->to operands.  The function
  * oclass in span.c computes the specific Ytype of an operand and then the set
  * of more general Ytypes that it satisfies is implied by the ycover table, set
- * up in InstInit.  For example, oclass distinguishes the constants 0 and 1
- * from the more general 8-bit constants, but InstInit says
+ * up in instinit.  For example, oclass distinguishes the constants 0 and 1
+ * from the more general 8-bit constants, but instinit says
  *
  *        ycover[Yi0*Ymax + Ys32] = 1;
  *        ycover[Yi1*Ymax + Ys32] = 1;
@@ -1768,7 +1768,7 @@ func span6(ctxt *obj.Link, s *obj.LSym, newprog obj.ProgAlloc) {
 	}
 
 	if ycover[0] == 0 {
-		ctxt.Diag("x86 tables not initialized, call x86.InstInit first")
+		ctxt.Diag("x86 tables not initialized, call x86.instinit first")
 	}
 
 	var asmbuf AsmBuf
@@ -1965,7 +1965,7 @@ func span6(ctxt *obj.Link, s *obj.LSym, newprog obj.ProgAlloc) {
 	}
 }
 
-func InstInit() {
+func instinit(ctxt *obj.Link) {
 	if ycover[0] != 0 {
 		// Already initialized; stop now.
 		// This happens in the cmd/asm tests,
@@ -1976,7 +1976,7 @@ func InstInit() {
 	for i := 1; optab[i].as != 0; i++ {
 		c := optab[i].as
 		if opindex[c&obj.AMask] != nil {
-			log.Fatalf("phase error in optab: %d (%v)", i, c)
+			ctxt.Diag("phase error in optab: %d (%v)", i, c)
 		}
 		opindex[c&obj.AMask] = &optab[i]
 	}

src/cmd/internal/obj/x86/obj6.go

@@ -1234,6 +1234,7 @@ var unaryDst = map[obj.As]bool{
 
 var Linkamd64 = obj.LinkArch{
 	Arch:       sys.ArchAMD64,
+	Init:       instinit,
 	Preprocess: preprocess,
 	Assemble:   span6,
 	Progedit:   progedit,
@@ -1242,6 +1243,7 @@ var Linkamd64 = obj.LinkArch{
 
 var Linkamd64p32 = obj.LinkArch{
 	Arch:       sys.ArchAMD64P32,
+	Init:       instinit,
 	Preprocess: preprocess,
 	Assemble:   span6,
 	Progedit:   progedit,
@@ -1250,6 +1252,7 @@ var Linkamd64p32 = obj.LinkArch{
 
 var Link386 = obj.LinkArch{
 	Arch:       sys.Arch386,
+	Init:       instinit,
 	Preprocess: preprocess,
 	Assemble:   span6,
 	Progedit:   progedit,