cmd/compile: refactor portable SSA Op handling

Several SSA ops will always behave identically regardless of target
architecture, so handle those within gc/ssa.go instead.

Passes toolstash-check -all.

Change-Id: I54d514e80ab86723e44332a5a38e3054cbca8c5d
Reviewed-on: https://go-review.googlesource.com/37931
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

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

@@ -147,7 +147,6 @@ func duff(size int64) (int64, int64) {
 }
 
 func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
-	s.SetPos(v.Pos)
 	switch v.Op {
 	case ssa.OpAMD64ADDQ, ssa.OpAMD64ADDL:
 		r := v.Reg()
@@ -714,12 +713,6 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
 		p.From.Type = obj.TYPE_REG
 		p.From.Reg = v.Args[0].Reg()
 		gc.AddrAuto(&p.To, v)
-	case ssa.OpPhi:
-		gc.CheckLoweredPhi(v)
-	case ssa.OpInitMem:
-		// memory arg needs no code
-	case ssa.OpArg:
-		// input args need no code
 	case ssa.OpAMD64LoweredGetClosurePtr:
 		// Closure pointer is DX.
 		gc.CheckLoweredGetClosurePtr(v)
@@ -821,10 +814,6 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
 		p.From.Reg = v.Args[0].Reg()
 		p.To.Type = obj.TYPE_REG
 		p.To.Reg = v.Reg()
-	case ssa.OpSP, ssa.OpSB:
-		// nothing to do
-	case ssa.OpSelect0, ssa.OpSelect1:
-		// nothing to do
 	case ssa.OpAMD64SETEQ, ssa.OpAMD64SETNE,
 		ssa.OpAMD64SETL, ssa.OpAMD64SETLE,
 		ssa.OpAMD64SETG, ssa.OpAMD64SETGE,
@@ -868,14 +857,6 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
 	case ssa.OpAMD64REPMOVSQ:
 		gc.Prog(x86.AREP)
 		gc.Prog(x86.AMOVSQ)
-	case ssa.OpVarDef:
-		gc.Gvardef(v.Aux.(*gc.Node))
-	case ssa.OpVarKill:
-		gc.Gvarkill(v.Aux.(*gc.Node))
-	case ssa.OpVarLive:
-		gc.Gvarlive(v.Aux.(*gc.Node))
-	case ssa.OpKeepAlive:
-		gc.KeepAlive(v)
 	case ssa.OpAMD64LoweredNilCheck:
 		// Issue a load which will fault if the input is nil.
 		// TODO: We currently use the 2-byte instruction TESTB AX, (reg).

src/cmd/compile/internal/arm/ssa.go

@@ -118,14 +118,7 @@ func genregshift(as obj.As, r0, r1, r2, r int16, typ int64) *obj.Prog {
 }
 
 func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
-	s.SetPos(v.Pos)
 	switch v.Op {
-	case ssa.OpInitMem:
-		// memory arg needs no code
-	case ssa.OpArg:
-		// input args need no code
-	case ssa.OpSP, ssa.OpSB, ssa.OpGetG:
-		// nothing to do
 	case ssa.OpCopy, ssa.OpARMMOVWconvert, ssa.OpARMMOVWreg:
 		if v.Type.IsMemory() {
 			return
@@ -165,8 +158,6 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
 		gc.AddrAuto(&p.From, v.Args[0])
 		p.To.Type = obj.TYPE_REG
 		p.To.Reg = v.Reg()
-	case ssa.OpPhi:
-		gc.CheckLoweredPhi(v)
 	case ssa.OpStoreReg:
 		if v.Type.IsFlags() {
 			v.Fatalf("store flags not implemented: %v", v.LongString())
@@ -783,14 +774,6 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
 		p4 := gc.Prog(arm.ABLE)
 		p4.To.Type = obj.TYPE_BRANCH
 		gc.Patch(p4, p)
-	case ssa.OpVarDef:
-		gc.Gvardef(v.Aux.(*gc.Node))
-	case ssa.OpVarKill:
-		gc.Gvarkill(v.Aux.(*gc.Node))
-	case ssa.OpVarLive:
-		gc.Gvarlive(v.Aux.(*gc.Node))
-	case ssa.OpKeepAlive:
-		gc.KeepAlive(v)
 	case ssa.OpARMEqual,
 		ssa.OpARMNotEqual,
 		ssa.OpARMLessThan,
@@ -814,8 +797,6 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
 		p.From.Offset = 1
 		p.To.Type = obj.TYPE_REG
 		p.To.Reg = v.Reg()
-	case ssa.OpSelect0, ssa.OpSelect1:
-		// nothing to do
 	case ssa.OpARMLoweredGetClosurePtr:
 		// Closure pointer is R7 (arm.REGCTXT).
 		gc.CheckLoweredGetClosurePtr(v)

src/cmd/compile/internal/arm64/ssa.go

@@ -92,14 +92,7 @@ func genshift(as obj.As, r0, r1, r int16, typ int64, s int64) *obj.Prog {
 }
 
 func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
-	s.SetPos(v.Pos)
 	switch v.Op {
-	case ssa.OpInitMem:
-		// memory arg needs no code
-	case ssa.OpArg:
-		// input args need no code
-	case ssa.OpSP, ssa.OpSB, ssa.OpGetG:
-		// nothing to do
 	case ssa.OpCopy, ssa.OpARM64MOVDconvert, ssa.OpARM64MOVDreg:
 		if v.Type.IsMemory() {
 			return
@@ -139,8 +132,6 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
 		gc.AddrAuto(&p.From, v.Args[0])
 		p.To.Type = obj.TYPE_REG
 		p.To.Reg = v.Reg()
-	case ssa.OpPhi:
-		gc.CheckLoweredPhi(v)
 	case ssa.OpStoreReg:
 		if v.Type.IsFlags() {
 			v.Fatalf("store flags not implemented: %v", v.LongString())
@@ -693,14 +684,6 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
 		if gc.Debug_checknil != 0 && v.Pos.Line() > 1 { // v.Line==1 in generated wrappers
 			gc.Warnl(v.Pos, "generated nil check")
 		}
-	case ssa.OpVarDef:
-		gc.Gvardef(v.Aux.(*gc.Node))
-	case ssa.OpVarKill:
-		gc.Gvarkill(v.Aux.(*gc.Node))
-	case ssa.OpVarLive:
-		gc.Gvarlive(v.Aux.(*gc.Node))
-	case ssa.OpKeepAlive:
-		gc.KeepAlive(v)
 	case ssa.OpARM64Equal,
 		ssa.OpARM64NotEqual,
 		ssa.OpARM64LessThan,
@@ -717,8 +700,6 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
 		p.From.Reg = condBits[v.Op]
 		p.To.Type = obj.TYPE_REG
 		p.To.Reg = v.Reg()
-	case ssa.OpSelect0, ssa.OpSelect1:
-		// nothing to do
 	case ssa.OpARM64LoweredGetClosurePtr:
 		// Closure pointer is R26 (arm64.REGCTXT).
 		gc.CheckLoweredGetClosurePtr(v)

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

@@ -4385,7 +4385,36 @@ func genssa(f *ssa.Func, ptxt *obj.Prog, gcargs, gclocals *Sym) {
 		Thearch.SSAMarkMoves(&s, b)
 		for _, v := range b.Values {
 			x := pc
+			s.SetPos(v.Pos)
+
+			switch v.Op {
+			case ssa.OpInitMem:
+				// memory arg needs no code
+			case ssa.OpArg:
+				// input args need no code
+			case ssa.OpSP, ssa.OpSB:
+				// nothing to do
+			case ssa.OpSelect0, ssa.OpSelect1:
+				// nothing to do
+			case ssa.OpGetG:
+				// nothing to do when there's a g register,
+				// and checkLower complains if there's not
+			case ssa.OpVarDef:
+				Gvardef(v.Aux.(*Node))
+			case ssa.OpVarKill:
+				Gvarkill(v.Aux.(*Node))
+			case ssa.OpVarLive:
+				Gvarlive(v.Aux.(*Node))
+			case ssa.OpKeepAlive:
+				KeepAlive(v)
+			case ssa.OpPhi:
+				CheckLoweredPhi(v)
+
+			default:
+				// let the backend handle it
 				Thearch.SSAGenValue(&s, v)
+			}
+
 			if logProgs {
 				for ; x != pc; x = x.Link {
 					valueProgs[x] = v

src/cmd/compile/internal/mips/ssa.go

@@ -74,16 +74,7 @@ func storeByType(t ssa.Type, r int16) obj.As {
 }
 
 func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
-	s.SetPos(v.Pos)
 	switch v.Op {
-	case ssa.OpInitMem:
-		// memory arg needs no code
-	case ssa.OpArg:
-		// input args need no code
-	case ssa.OpSP, ssa.OpSB, ssa.OpGetG:
-		// nothing to do
-	case ssa.OpSelect0, ssa.OpSelect1:
-		// nothing to do
 	case ssa.OpCopy, ssa.OpMIPSMOVWconvert, ssa.OpMIPSMOVWreg:
 		t := v.Type
 		if t.IsMemory() {
@@ -778,16 +769,6 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
 		p6 := gc.Prog(obj.ANOP)
 		gc.Patch(p2, p6)
 
-	case ssa.OpVarDef:
-		gc.Gvardef(v.Aux.(*gc.Node))
-	case ssa.OpVarKill:
-		gc.Gvarkill(v.Aux.(*gc.Node))
-	case ssa.OpVarLive:
-		gc.Gvarlive(v.Aux.(*gc.Node))
-	case ssa.OpKeepAlive:
-		gc.KeepAlive(v)
-	case ssa.OpPhi:
-		gc.CheckLoweredPhi(v)
 	case ssa.OpMIPSLoweredNilCheck:
 		// Issue a load which will fault if arg is nil.
 		p := gc.Prog(mips.AMOVB)

src/cmd/compile/internal/mips64/ssa.go

@@ -82,14 +82,7 @@ func storeByType(t ssa.Type, r int16) obj.As {
 }
 
 func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
-	s.SetPos(v.Pos)
 	switch v.Op {
-	case ssa.OpInitMem:
-		// memory arg needs no code
-	case ssa.OpArg:
-		// input args need no code
-	case ssa.OpSP, ssa.OpSB, ssa.OpGetG:
-		// nothing to do
 	case ssa.OpCopy, ssa.OpMIPS64MOVVconvert, ssa.OpMIPS64MOVVreg:
 		if v.Type.IsMemory() {
 			return
@@ -141,8 +134,6 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
 			p.To.Type = obj.TYPE_REG
 			p.To.Reg = r
 		}
-	case ssa.OpPhi:
-		gc.CheckLoweredPhi(v)
 	case ssa.OpStoreReg:
 		if v.Type.IsFlags() {
 			v.Fatalf("store flags not implemented: %v", v.LongString())
@@ -551,14 +542,6 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
 		if gc.Debug_checknil != 0 && v.Pos.Line() > 1 { // v.Pos.Line()==1 in generated wrappers
 			gc.Warnl(v.Pos, "generated nil check")
 		}
-	case ssa.OpVarDef:
-		gc.Gvardef(v.Aux.(*gc.Node))
-	case ssa.OpVarKill:
-		gc.Gvarkill(v.Aux.(*gc.Node))
-	case ssa.OpVarLive:
-		gc.Gvarlive(v.Aux.(*gc.Node))
-	case ssa.OpKeepAlive:
-		gc.KeepAlive(v)
 	case ssa.OpMIPS64FPFlagTrue,
 		ssa.OpMIPS64FPFlagFalse:
 		// MOVV	$0, r
@@ -582,8 +565,6 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
 		p3.To.Reg = v.Reg()
 		p4 := gc.Prog(obj.ANOP) // not a machine instruction, for branch to land
 		gc.Patch(p2, p4)
-	case ssa.OpSelect0, ssa.OpSelect1:
-		// nothing to do
 	case ssa.OpMIPS64LoweredGetClosurePtr:
 		// Closure pointer is R22 (mips.REGCTXT).
 		gc.CheckLoweredGetClosurePtr(v)

src/cmd/compile/internal/ppc64/ssa.go

@@ -143,15 +143,7 @@ func ssaGenISEL(v *ssa.Value, cr int64, r1, r2 int16) {
 }
 
 func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
-	s.SetPos(v.Pos)
 	switch v.Op {
-	case ssa.OpInitMem:
-		// memory arg needs no code
-	case ssa.OpArg:
-		// input args need no code
-	case ssa.OpSP, ssa.OpSB, ssa.OpGetG:
-		// nothing to do
-
 	case ssa.OpCopy, ssa.OpPPC64MOVDconvert:
 		t := v.Type
 		if t.IsMemory() {
@@ -1046,19 +1038,6 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
 		if gc.Maxarg < v.AuxInt {
 			gc.Maxarg = v.AuxInt
 		}
-	case ssa.OpVarDef:
-		gc.Gvardef(v.Aux.(*gc.Node))
-	case ssa.OpVarKill:
-		gc.Gvarkill(v.Aux.(*gc.Node))
-	case ssa.OpVarLive:
-		gc.Gvarlive(v.Aux.(*gc.Node))
-	case ssa.OpKeepAlive:
-		gc.KeepAlive(v)
-	case ssa.OpPhi:
-		gc.CheckLoweredPhi(v)
-	case ssa.OpSelect0, ssa.OpSelect1:
-		// nothing to do
-
 	case ssa.OpPPC64LoweredNilCheck:
 		// Issue a load which will fault if arg is nil.
 		p := gc.Prog(ppc64.AMOVBZ)

src/cmd/compile/internal/s390x/ssa.go

@@ -156,7 +156,6 @@ func opregregimm(op obj.As, dest, src int16, off int64) *obj.Prog {
 }
 
 func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
-	s.SetPos(v.Pos)
 	switch v.Op {
 	case ssa.OpS390XSLD, ssa.OpS390XSLW,
 		ssa.OpS390XSRD, ssa.OpS390XSRW,
@@ -470,12 +469,6 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
 		p.From.Type = obj.TYPE_REG
 		p.From.Reg = v.Args[0].Reg()
 		gc.AddrAuto(&p.To, v)
-	case ssa.OpPhi:
-		gc.CheckLoweredPhi(v)
-	case ssa.OpInitMem:
-		// memory arg needs no code
-	case ssa.OpArg:
-		// input args need no code
 	case ssa.OpS390XLoweredGetClosurePtr:
 		// Closure pointer is R12 (already)
 		gc.CheckLoweredGetClosurePtr(v)
@@ -565,18 +558,6 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
 		p.From.Reg = v.Args[0].Reg()
 		p.To.Type = obj.TYPE_REG
 		p.To.Reg = v.Reg()
-	case ssa.OpSP, ssa.OpSB:
-		// nothing to do
-	case ssa.OpSelect0, ssa.OpSelect1:
-		// nothing to do
-	case ssa.OpVarDef:
-		gc.Gvardef(v.Aux.(*gc.Node))
-	case ssa.OpVarKill:
-		gc.Gvarkill(v.Aux.(*gc.Node))
-	case ssa.OpVarLive:
-		gc.Gvarlive(v.Aux.(*gc.Node))
-	case ssa.OpKeepAlive:
-		gc.KeepAlive(v)
 	case ssa.OpS390XInvertFlags:
 		v.Fatalf("InvertFlags should never make it to codegen %v", v.LongString())
 	case ssa.OpS390XFlagEQ, ssa.OpS390XFlagLT, ssa.OpS390XFlagGT:

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

@@ -114,8 +114,6 @@ func opregreg(op obj.As, dest, src int16) *obj.Prog {
 }
 
 func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
-	s.SetPos(v.Pos)
-
 	if gc.Thearch.Use387 {
 		if ssaGenValue387(s, v) {
 			return // v was handled by 387 generation.
@@ -641,12 +639,6 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
 		p.From.Type = obj.TYPE_REG
 		p.From.Reg = v.Args[0].Reg()
 		gc.AddrAuto(&p.To, v)
-	case ssa.OpPhi:
-		gc.CheckLoweredPhi(v)
-	case ssa.OpInitMem:
-		// memory arg needs no code
-	case ssa.OpArg:
-		// input args need no code
 	case ssa.Op386LoweredGetClosurePtr:
 		// Closure pointer is DX.
 		gc.CheckLoweredGetClosurePtr(v)
@@ -744,8 +736,6 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
 		p.From.Reg = v.Args[0].Reg()
 		p.To.Type = obj.TYPE_REG
 		p.To.Reg = v.Reg()
-	case ssa.OpSP, ssa.OpSB, ssa.OpSelect0, ssa.OpSelect1:
-		// nothing to do
 	case ssa.Op386SETEQ, ssa.Op386SETNE,
 		ssa.Op386SETL, ssa.Op386SETLE,
 		ssa.Op386SETG, ssa.Op386SETGE,
@@ -785,14 +775,6 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
 	case ssa.Op386REPMOVSL:
 		gc.Prog(x86.AREP)
 		gc.Prog(x86.AMOVSL)
-	case ssa.OpVarDef:
-		gc.Gvardef(v.Aux.(*gc.Node))
-	case ssa.OpVarKill:
-		gc.Gvarkill(v.Aux.(*gc.Node))
-	case ssa.OpVarLive:
-		gc.Gvarlive(v.Aux.(*gc.Node))
-	case ssa.OpKeepAlive:
-		gc.KeepAlive(v)
 	case ssa.Op386LoweredNilCheck:
 		// Issue a load which will fault if the input is nil.
 		// TODO: We currently use the 2-byte instruction TESTB AX, (reg).