cmd/compile: remove some nacl SSA rules

Updates golang/go#30439

Change-Id: I7ef5301fbd650d26a37a1241ddf7ca1ccd58b89d
Reviewed-on: https://go-review.googlesource.com/c/go/+/200941
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

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

@@ -947,13 +947,6 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
 		p.To.Sym = gc.BoundsCheckFunc[v.AuxInt]
 		s.UseArgs(int64(2 * gc.Widthptr)) // space used in callee args area by assembly stubs
 
-	case ssa.OpAMD64LoweredPanicExtendA, ssa.OpAMD64LoweredPanicExtendB, ssa.OpAMD64LoweredPanicExtendC:
-		p := s.Prog(obj.ACALL)
-		p.To.Type = obj.TYPE_MEM
-		p.To.Name = obj.NAME_EXTERN
-		p.To.Sym = gc.ExtendCheckFunc[v.AuxInt]
-		s.UseArgs(int64(3 * gc.Widthptr)) // space used in callee args area by assembly stubs
-
 	case ssa.OpAMD64NEGQ, ssa.OpAMD64NEGL,
 		ssa.OpAMD64BSWAPQ, ssa.OpAMD64BSWAPL,
 		ssa.OpAMD64NOTQ, ssa.OpAMD64NOTL:

src/cmd/compile/internal/ssa/gen/AMD64.rules

@@ -567,11 +567,6 @@
 (PanicBounds [kind] x y mem) && boundsABI(kind) == 1 -> (LoweredPanicBoundsB [kind] x y mem)
 (PanicBounds [kind] x y mem) && boundsABI(kind) == 2 -> (LoweredPanicBoundsC [kind] x y mem)
 
-// For amd64p32
-(PanicExtend [kind] hi lo y mem) && boundsABI(kind) == 0 -> (LoweredPanicExtendA [kind] hi lo y mem)
-(PanicExtend [kind] hi lo y mem) && boundsABI(kind) == 1 -> (LoweredPanicExtendB [kind] hi lo y mem)
-(PanicExtend [kind] hi lo y mem) && boundsABI(kind) == 2 -> (LoweredPanicExtendC [kind] hi lo y mem)
-
 // ***************************
 // Above: lowering rules
 // Below: optimizations

src/cmd/compile/internal/ssa/gen/AMD64Ops.go

@@ -94,7 +94,6 @@ func init() {
 		cx         = buildReg("CX")
 		dx         = buildReg("DX")
 		bx         = buildReg("BX")
-		si         = buildReg("SI")
 		gp         = buildReg("AX CX DX BX BP SI DI R8 R9 R10 R11 R12 R13 R14 R15")
 		fp         = buildReg("X0 X1 X2 X3 X4 X5 X6 X7 X8 X9 X10 X11 X12 X13 X14 X15")
 		gpsp       = gp | buildReg("SP")
@@ -718,12 +717,6 @@ func init() {
 		{name: "LoweredPanicBoundsB", argLength: 3, aux: "Int64", reg: regInfo{inputs: []regMask{cx, dx}}, typ: "Mem"}, // arg0=idx, arg1=len, arg2=mem, returns memory. AuxInt contains report code (see PanicBounds in generic.go).
 		{name: "LoweredPanicBoundsC", argLength: 3, aux: "Int64", reg: regInfo{inputs: []regMask{ax, cx}}, typ: "Mem"}, // arg0=idx, arg1=len, arg2=mem, returns memory. AuxInt contains report code (see PanicBounds in generic.go).
 
-		// amd64p32 only: PanicBounds ops take 32-bit indexes.
-		// The Extend ops are the same as the Bounds ops except the indexes are 64-bit.
-		{name: "LoweredPanicExtendA", argLength: 4, aux: "Int64", reg: regInfo{inputs: []regMask{si, dx, bx}}, typ: "Mem"}, // arg0=idxHi, arg1=idxLo, arg2=len, arg3=mem, returns memory. AuxInt contains report code (see PanicExtend in genericOps.go).
-		{name: "LoweredPanicExtendB", argLength: 4, aux: "Int64", reg: regInfo{inputs: []regMask{si, cx, dx}}, typ: "Mem"}, // arg0=idxHi, arg1=idxLo, arg2=len, arg3=mem, returns memory. AuxInt contains report code (see PanicExtend in genericOps.go).
-		{name: "LoweredPanicExtendC", argLength: 4, aux: "Int64", reg: regInfo{inputs: []regMask{si, ax, cx}}, typ: "Mem"}, // arg0=idxHi, arg1=idxLo, arg2=len, arg3=mem, returns memory. AuxInt contains report code (see PanicExtend in genericOps.go).
-
 		// Constant flag values. For any comparison, there are 5 possible
 		// outcomes: the three from the signed total order (<,==,>) and the
 		// three from the unsigned total order. The == cases overlap.

src/cmd/compile/internal/ssa/gen/ARMOps.go

@@ -154,7 +154,7 @@ func init() {
 			reg: regInfo{
 				inputs:   []regMask{buildReg("R1"), buildReg("R0")},
 				outputs:  []regMask{buildReg("R0"), buildReg("R1")},
-				clobbers: buildReg("R2 R3 R14"), // also clobbers R12 on NaCl (modified in ../config.go)
+				clobbers: buildReg("R2 R3 R14"),
 			},
 			clobberFlags: true,
 			typ:          "(UInt32,UInt32)",

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

@@ -868,9 +868,6 @@ const (
 	OpAMD64LoweredPanicBoundsA
 	OpAMD64LoweredPanicBoundsB
 	OpAMD64LoweredPanicBoundsC
-	OpAMD64LoweredPanicExtendA
-	OpAMD64LoweredPanicExtendB
-	OpAMD64LoweredPanicExtendC
 	OpAMD64FlagEQ
 	OpAMD64FlagLT_ULT
 	OpAMD64FlagLT_UGT
@@ -11317,42 +11314,6 @@ var opcodeTable = [...]opInfo{
 			},
 		},
 	},
-	{
-		name:    "LoweredPanicExtendA",
-		auxType: auxInt64,
-		argLen:  4,
-		reg: regInfo{
-			inputs: []inputInfo{
-				{0, 64}, // SI
-				{1, 4},  // DX
-				{2, 8},  // BX
-			},
-		},
-	},
-	{
-		name:    "LoweredPanicExtendB",
-		auxType: auxInt64,
-		argLen:  4,
-		reg: regInfo{
-			inputs: []inputInfo{
-				{0, 64}, // SI
-				{1, 2},  // CX
-				{2, 4},  // DX
-			},
-		},
-	},
-	{
-		name:    "LoweredPanicExtendC",
-		auxType: auxInt64,
-		argLen:  4,
-		reg: regInfo{
-			inputs: []inputInfo{
-				{0, 64}, // SI
-				{1, 1},  // AX
-				{2, 2},  // CX
-			},
-		},
-	},
 	{
 		name:   "FlagEQ",
 		argLen: 0,

src/cmd/compile/internal/ssa/rewriteAMD64.go

@@ -990,8 +990,6 @@ func rewriteValueAMD64(v *Value) bool {
 		return rewriteValueAMD64_OpOrB_0(v)
 	case OpPanicBounds:
 		return rewriteValueAMD64_OpPanicBounds_0(v)
-	case OpPanicExtend:
-		return rewriteValueAMD64_OpPanicExtend_0(v)
 	case OpPopCount16:
 		return rewriteValueAMD64_OpPopCount16_0(v)
 	case OpPopCount32:
@@ -55176,69 +55174,6 @@ func rewriteValueAMD64_OpPanicBounds_0(v *Value) bool {
 	}
 	return false
 }
-func rewriteValueAMD64_OpPanicExtend_0(v *Value) bool {
-	// match: (PanicExtend [kind] hi lo y mem)
-	// cond: boundsABI(kind) == 0
-	// result: (LoweredPanicExtendA [kind] hi lo y mem)
-	for {
-		kind := v.AuxInt
-		mem := v.Args[3]
-		hi := v.Args[0]
-		lo := v.Args[1]
-		y := v.Args[2]
-		if !(boundsABI(kind) == 0) {
-			break
-		}
-		v.reset(OpAMD64LoweredPanicExtendA)
-		v.AuxInt = kind
-		v.AddArg(hi)
-		v.AddArg(lo)
-		v.AddArg(y)
-		v.AddArg(mem)
-		return true
-	}
-	// match: (PanicExtend [kind] hi lo y mem)
-	// cond: boundsABI(kind) == 1
-	// result: (LoweredPanicExtendB [kind] hi lo y mem)
-	for {
-		kind := v.AuxInt
-		mem := v.Args[3]
-		hi := v.Args[0]
-		lo := v.Args[1]
-		y := v.Args[2]
-		if !(boundsABI(kind) == 1) {
-			break
-		}
-		v.reset(OpAMD64LoweredPanicExtendB)
-		v.AuxInt = kind
-		v.AddArg(hi)
-		v.AddArg(lo)
-		v.AddArg(y)
-		v.AddArg(mem)
-		return true
-	}
-	// match: (PanicExtend [kind] hi lo y mem)
-	// cond: boundsABI(kind) == 2
-	// result: (LoweredPanicExtendC [kind] hi lo y mem)
-	for {
-		kind := v.AuxInt
-		mem := v.Args[3]
-		hi := v.Args[0]
-		lo := v.Args[1]
-		y := v.Args[2]
-		if !(boundsABI(kind) == 2) {
-			break
-		}
-		v.reset(OpAMD64LoweredPanicExtendC)
-		v.AuxInt = kind
-		v.AddArg(hi)
-		v.AddArg(lo)
-		v.AddArg(y)
-		v.AddArg(mem)
-		return true
-	}
-	return false
-}
 func rewriteValueAMD64_OpPopCount16_0(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types