cmd/compile: reduce rulegen's for loop verbosity

A lot of the naked for loops begin like:

	for {
		v := b.Control
		if v.Op != OpConstBool {
			break
		}
		...
		return true
	}

Instead, write them out in a more compact and readable way:

	for v.Op == OpConstBool {
		...
		return true
	}

This requires the addition of two bytes.Buffer writers, as this helps us
make a decision based on future pieces of generated code. This probably
makes rulegen slightly slower, but that's not noticeable; the code
generation still takes ~3.5s on my laptop, excluding build time.

The "v := b.Control" declaration can be moved to the top of each
function. Even though the rules can modify b.Control when firing, they
also make the function return, so v can't be used again.

While at it, remove three unnecessary lines from the top of each
rewriteBlock func.

In total, this results in ~4k lines removed from the generated code, and
a slight improvement in readability.

Change-Id: I317e4c6a4842c64df506f4513375475fad2aeec5
Reviewed-on: https://go-review.googlesource.com/c/go/+/167399
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>

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

@@ -217,7 +217,7 @@ func genRulesSuffix(arch arch, suff string) {
 
 				canFail = false
 				fmt.Fprintf(buf, "for {\n")
-				pos, matchCanFail := genMatch(buf, arch, match, rule.loc)
+				pos, _, matchCanFail := genMatch(buf, arch, match, rule.loc)
 				if pos == "" {
 					pos = "v.Pos"
 				}
@@ -273,11 +273,10 @@ func genRulesSuffix(arch arch, suff string) {
 	// so we can make this one function with a switch.
 	fmt.Fprintf(w, "func rewriteBlock%s%s(b *Block) bool {\n", arch.name, suff)
 	fmt.Fprintln(w, "config := b.Func.Config")
-	fmt.Fprintln(w, "_ = config")
-	fmt.Fprintln(w, "fe := b.Func.fe")
-	fmt.Fprintln(w, "_ = fe")
 	fmt.Fprintln(w, "typ := &config.Types")
 	fmt.Fprintln(w, "_ = typ")
+	fmt.Fprintln(w, "v := b.Control")
+	fmt.Fprintln(w, "_ = v")
 	fmt.Fprintf(w, "switch b.Kind {\n")
 	ops = nil
 	for op := range blockrules {
@@ -292,27 +291,26 @@ func genRulesSuffix(arch arch, suff string) {
 			fmt.Fprintf(w, "// cond: %s\n", cond)
 			fmt.Fprintf(w, "// result: %s\n", result)
 
-			fmt.Fprintf(w, "for {\n")
-
 			_, _, _, aux, s := extract(match) // remove parens, then split
 
+			loopw := new(bytes.Buffer)
+
 			// check match of control value
 			pos := ""
+			checkOp := ""
 			if s[0] != "nil" {
-				fmt.Fprintf(w, "v := b.Control\n")
 				if strings.Contains(s[0], "(") {
-					pos, _ = genMatch0(w, arch, s[0], "v", map[string]struct{}{}, false, rule.loc)
+					pos, checkOp, _ = genMatch0(loopw, arch, s[0], "v", map[string]struct{}{}, rule.loc)
 				} else {
-					fmt.Fprintf(w, "_ = v\n") // in case we don't use v
+					fmt.Fprintf(loopw, "%s := b.Control\n", s[0])
-					fmt.Fprintf(w, "%s := b.Control\n", s[0])
 				}
 			}
 			if aux != "" {
-				fmt.Fprintf(w, "%s := b.Aux\n", aux)
+				fmt.Fprintf(loopw, "%s := b.Aux\n", aux)
 			}
 
 			if cond != "" {
-				fmt.Fprintf(w, "if !(%s) {\nbreak\n}\n", cond)
+				fmt.Fprintf(loopw, "if !(%s) {\nbreak\n}\n", cond)
 			}
 
 			// Rule matches. Generate result.
@@ -338,19 +336,19 @@ func genRulesSuffix(arch arch, suff string) {
 				log.Fatalf("unmatched successors %v in %s", m, rule)
 			}
 
-			fmt.Fprintf(w, "b.Kind = %s\n", blockName(outop, arch))
+			fmt.Fprintf(loopw, "b.Kind = %s\n", blockName(outop, arch))
 			if t[0] == "nil" {
-				fmt.Fprintf(w, "b.SetControl(nil)\n")
+				fmt.Fprintf(loopw, "b.SetControl(nil)\n")
 			} else {
 				if pos == "" {
 					pos = "v.Pos"
 				}
-				fmt.Fprintf(w, "b.SetControl(%s)\n", genResult0(w, arch, t[0], new(int), false, false, rule.loc, pos))
+				fmt.Fprintf(loopw, "b.SetControl(%s)\n", genResult0(loopw, arch, t[0], new(int), false, false, rule.loc, pos))
 			}
 			if aux != "" {
-				fmt.Fprintf(w, "b.Aux = %s\n", aux)
+				fmt.Fprintf(loopw, "b.Aux = %s\n", aux)
 			} else {
-				fmt.Fprintln(w, "b.Aux = nil")
+				fmt.Fprintln(loopw, "b.Aux = nil")
 			}
 
 			succChanged := false
@@ -366,13 +364,20 @@ func genRulesSuffix(arch arch, suff string) {
 				if succs[0] != newsuccs[1] || succs[1] != newsuccs[0] {
 					log.Fatalf("can only handle swapped successors in %s", rule)
 				}
-				fmt.Fprintln(w, "b.swapSuccessors()")
+				fmt.Fprintln(loopw, "b.swapSuccessors()")
 			}
 
 			if *genLog {
-				fmt.Fprintf(w, "logRule(\"%s\")\n", rule.loc)
+				fmt.Fprintf(loopw, "logRule(\"%s\")\n", rule.loc)
 			}
-			fmt.Fprintf(w, "return true\n")
+			fmt.Fprintf(loopw, "return true\n")
+
+			if checkOp != "" {
+				fmt.Fprintf(w, "for v.Op == %s {\n", checkOp)
+			} else {
+				fmt.Fprintf(w, "for {\n")
+			}
+			io.Copy(w, loopw)
 
 			fmt.Fprintf(w, "}\n")
 		}
@@ -398,24 +403,18 @@ func genRulesSuffix(arch arch, suff string) {
 
 // genMatch returns the variable whose source position should be used for the
 // result (or "" if no opinion), and a boolean that reports whether the match can fail.
-func genMatch(w io.Writer, arch arch, match string, loc string) (string, bool) {
+func genMatch(w io.Writer, arch arch, match string, loc string) (pos, checkOp string, canFail bool) {
-	return genMatch0(w, arch, match, "v", map[string]struct{}{}, true, loc)
+	return genMatch0(w, arch, match, "v", map[string]struct{}{}, loc)
 }
 
-func genMatch0(w io.Writer, arch arch, match, v string, m map[string]struct{}, top bool, loc string) (string, bool) {
+func genMatch0(w io.Writer, arch arch, match, v string, m map[string]struct{}, loc string) (pos, checkOp string, canFail bool) {
 	if match[0] != '(' || match[len(match)-1] != ')' {
 		panic("non-compound expr in genMatch0: " + match)
 	}
-	pos := ""
-	canFail := false
-
 	op, oparch, typ, auxint, aux, args := parseValue(match, arch, loc)
 
-	// check op
+	checkOp = fmt.Sprintf("Op%s%s", oparch, op.name)
-	if !top {
+
-		fmt.Fprintf(w, "if %s.Op != Op%s%s {\nbreak\n}\n", v, oparch, op.name)
-		canFail = true
-	}
 	if op.faultOnNilArg0 || op.faultOnNilArg1 {
 		// Prefer the position of an instruction which could fault.
 		pos = v + ".Pos"
@@ -521,8 +520,13 @@ func genMatch0(w io.Writer, arch arch, match, v string, m map[string]struct{}, t
 		if argname == "b" {
 			log.Fatalf("don't name args 'b', it is ambiguous with blocks")
 		}
+
 		fmt.Fprintf(w, "%s := %s.Args[%d]\n", argname, v, i)
-		argPos, argCanFail := genMatch0(w, arch, arg, argname, m, false, loc)
+		w2 := new(bytes.Buffer)
+		argPos, argCheckOp, _ := genMatch0(w2, arch, arg, argname, m, loc)
+		fmt.Fprintf(w, "if %s.Op != %s {\nbreak\n}\n", argname, argCheckOp)
+		io.Copy(w, w2)
+
 		if argPos != "" {
 			// Keep the argument in preference to the parent, as the
 			// argument is normally earlier in program flow.
@@ -531,16 +535,14 @@ func genMatch0(w io.Writer, arch arch, match, v string, m map[string]struct{}, t
 			// in the program flow.
 			pos = argPos
 		}
-		if argCanFail {
+		canFail = true
-			canFail = true
-		}
 	}
 
 	if op.argLength == -1 {
 		fmt.Fprintf(w, "if len(%s.Args) != %d {\nbreak\n}\n", v, len(args))
 		canFail = true
 	}
-	return pos, canFail
+	return pos, checkOp, canFail
 }
 
 func genResult(w io.Writer, arch arch, result string, loc string, pos string) {

src/cmd/compile/internal/ssa/rewrite386splitload.go

@@ -169,11 +169,10 @@ func rewriteValue386splitload_Op386CMPWload_0(v *Value) bool {
 }
 func rewriteBlock386splitload(b *Block) bool {
 	config := b.Func.Config
-	_ = config
-	fe := b.Func.fe
-	_ = fe
 	typ := &config.Types
 	_ = typ
+	v := b.Control
+	_ = v
 	switch b.Kind {
 	}
 	return false

src/cmd/compile/internal/ssa/rewriteAMD64splitload.go

@@ -218,11 +218,10 @@ func rewriteValueAMD64splitload_OpAMD64CMPWload_0(v *Value) bool {
 }
 func rewriteBlockAMD64splitload(b *Block) bool {
 	config := b.Func.Config
-	_ = config
-	fe := b.Func.fe
-	_ = fe
 	typ := &config.Types
 	_ = typ
+	v := b.Control
+	_ = v
 	switch b.Kind {
 	}
 	return false

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

@@ -9317,21 +9317,16 @@ func rewriteValueMIPS_OpZeromask_0(v *Value) bool {
 }
 func rewriteBlockMIPS(b *Block) bool {
 	config := b.Func.Config
-	_ = config
-	fe := b.Func.fe
-	_ = fe
 	typ := &config.Types
 	_ = typ
+	v := b.Control
+	_ = v
 	switch b.Kind {
 	case BlockMIPSEQ:
 		// match: (EQ (FPFlagTrue cmp) yes no)
 		// cond:
 		// result: (FPF cmp yes no)
-		for {
+		for v.Op == OpMIPSFPFlagTrue {
-			v := b.Control
-			if v.Op != OpMIPSFPFlagTrue {
-				break
-			}
 			cmp := v.Args[0]
 			b.Kind = BlockMIPSFPF
 			b.SetControl(cmp)
@@ -9341,11 +9336,7 @@ func rewriteBlockMIPS(b *Block) bool {
 		// match: (EQ (FPFlagFalse cmp) yes no)
 		// cond:
 		// result: (FPT cmp yes no)
-		for {
+		for v.Op == OpMIPSFPFlagFalse {
-			v := b.Control
-			if v.Op != OpMIPSFPFlagFalse {
-				break
-			}
 			cmp := v.Args[0]
 			b.Kind = BlockMIPSFPT
 			b.SetControl(cmp)
@@ -9355,11 +9346,7 @@ func rewriteBlockMIPS(b *Block) bool {
 		// match: (EQ (XORconst [1] cmp:(SGT _ _)) yes no)
 		// cond:
 		// result: (NE cmp yes no)
-		for {
+		for v.Op == OpMIPSXORconst {
-			v := b.Control
-			if v.Op != OpMIPSXORconst {
-				break
-			}
 			if v.AuxInt != 1 {
 				break
 			}
@@ -9376,11 +9363,7 @@ func rewriteBlockMIPS(b *Block) bool {
 		// match: (EQ (XORconst [1] cmp:(SGTU _ _)) yes no)
 		// cond:
 		// result: (NE cmp yes no)
-		for {
+		for v.Op == OpMIPSXORconst {
-			v := b.Control
-			if v.Op != OpMIPSXORconst {
-				break
-			}
 			if v.AuxInt != 1 {
 				break
 			}
@@ -9397,11 +9380,7 @@ func rewriteBlockMIPS(b *Block) bool {
 		// match: (EQ (XORconst [1] cmp:(SGTconst _)) yes no)
 		// cond:
 		// result: (NE cmp yes no)
-		for {
+		for v.Op == OpMIPSXORconst {
-			v := b.Control
-			if v.Op != OpMIPSXORconst {
-				break
-			}
 			if v.AuxInt != 1 {
 				break
 			}
@@ -9417,11 +9396,7 @@ func rewriteBlockMIPS(b *Block) bool {
 		// match: (EQ (XORconst [1] cmp:(SGTUconst _)) yes no)
 		// cond:
 		// result: (NE cmp yes no)
-		for {
+		for v.Op == OpMIPSXORconst {
-			v := b.Control
-			if v.Op != OpMIPSXORconst {
-				break
-			}
 			if v.AuxInt != 1 {
 				break
 			}
@@ -9437,11 +9412,7 @@ func rewriteBlockMIPS(b *Block) bool {
 		// match: (EQ (XORconst [1] cmp:(SGTzero _)) yes no)
 		// cond:
 		// result: (NE cmp yes no)
-		for {
+		for v.Op == OpMIPSXORconst {
-			v := b.Control
-			if v.Op != OpMIPSXORconst {
-				break
-			}
 			if v.AuxInt != 1 {
 				break
 			}
@@ -9457,11 +9428,7 @@ func rewriteBlockMIPS(b *Block) bool {
 		// match: (EQ (XORconst [1] cmp:(SGTUzero _)) yes no)
 		// cond:
 		// result: (NE cmp yes no)
-		for {
+		for v.Op == OpMIPSXORconst {
-			v := b.Control
-			if v.Op != OpMIPSXORconst {
-				break
-			}
 			if v.AuxInt != 1 {
 				break
 			}
@@ -9477,11 +9444,7 @@ func rewriteBlockMIPS(b *Block) bool {
 		// match: (EQ (SGTUconst [1] x) yes no)
 		// cond:
 		// result: (NE x yes no)
-		for {
+		for v.Op == OpMIPSSGTUconst {
-			v := b.Control
-			if v.Op != OpMIPSSGTUconst {
-				break
-			}
 			if v.AuxInt != 1 {
 				break
 			}
@@ -9494,11 +9457,7 @@ func rewriteBlockMIPS(b *Block) bool {
 		// match: (EQ (SGTUzero x) yes no)
 		// cond:
 		// result: (EQ x yes no)
-		for {
+		for v.Op == OpMIPSSGTUzero {
-			v := b.Control
-			if v.Op != OpMIPSSGTUzero {
-				break
-			}
 			x := v.Args[0]
 			b.Kind = BlockMIPSEQ
 			b.SetControl(x)
@@ -9508,11 +9467,7 @@ func rewriteBlockMIPS(b *Block) bool {
 		// match: (EQ (SGTconst [0] x) yes no)
 		// cond:
 		// result: (GEZ x yes no)
-		for {
+		for v.Op == OpMIPSSGTconst {
-			v := b.Control
-			if v.Op != OpMIPSSGTconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -9525,11 +9480,7 @@ func rewriteBlockMIPS(b *Block) bool {
 		// match: (EQ (SGTzero x) yes no)
 		// cond:
 		// result: (LEZ x yes no)
-		for {
+		for v.Op == OpMIPSSGTzero {
-			v := b.Control
-			if v.Op != OpMIPSSGTzero {
-				break
-			}
 			x := v.Args[0]
 			b.Kind = BlockMIPSLEZ
 			b.SetControl(x)
@@ -9539,11 +9490,7 @@ func rewriteBlockMIPS(b *Block) bool {
 		// match: (EQ (MOVWconst [0]) yes no)
 		// cond:
 		// result: (First nil yes no)
-		for {
+		for v.Op == OpMIPSMOVWconst {
-			v := b.Control
-			if v.Op != OpMIPSMOVWconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -9555,11 +9502,7 @@ func rewriteBlockMIPS(b *Block) bool {
 		// match: (EQ (MOVWconst [c]) yes no)
 		// cond: c != 0
 		// result: (First nil no yes)
-		for {
+		for v.Op == OpMIPSMOVWconst {
-			v := b.Control
-			if v.Op != OpMIPSMOVWconst {
-				break
-			}
 			c := v.AuxInt
 			if !(c != 0) {
 				break
@@ -9574,11 +9517,7 @@ func rewriteBlockMIPS(b *Block) bool {
 		// match: (GEZ (MOVWconst [c]) yes no)
 		// cond: int32(c) >= 0
 		// result: (First nil yes no)
-		for {
+		for v.Op == OpMIPSMOVWconst {
-			v := b.Control
-			if v.Op != OpMIPSMOVWconst {
-				break
-			}
 			c := v.AuxInt
 			if !(int32(c) >= 0) {
 				break
@@ -9591,11 +9530,7 @@ func rewriteBlockMIPS(b *Block) bool {
 		// match: (GEZ (MOVWconst [c]) yes no)
 		// cond: int32(c) < 0
 		// result: (First nil no yes)
-		for {
+		for v.Op == OpMIPSMOVWconst {
-			v := b.Control
-			if v.Op != OpMIPSMOVWconst {
-				break
-			}
 			c := v.AuxInt
 			if !(int32(c) < 0) {
 				break
@@ -9610,11 +9545,7 @@ func rewriteBlockMIPS(b *Block) bool {
 		// match: (GTZ (MOVWconst [c]) yes no)
 		// cond: int32(c) > 0
 		// result: (First nil yes no)
-		for {
+		for v.Op == OpMIPSMOVWconst {
-			v := b.Control
-			if v.Op != OpMIPSMOVWconst {
-				break
-			}
 			c := v.AuxInt
 			if !(int32(c) > 0) {
 				break
@@ -9627,11 +9558,7 @@ func rewriteBlockMIPS(b *Block) bool {
 		// match: (GTZ (MOVWconst [c]) yes no)
 		// cond: int32(c) <= 0
 		// result: (First nil no yes)
-		for {
+		for v.Op == OpMIPSMOVWconst {
-			v := b.Control
-			if v.Op != OpMIPSMOVWconst {
-				break
-			}
 			c := v.AuxInt
 			if !(int32(c) <= 0) {
 				break
@@ -9647,8 +9574,6 @@ func rewriteBlockMIPS(b *Block) bool {
 		// cond:
 		// result: (NE cond yes no)
 		for {
-			v := b.Control
-			_ = v
 			cond := b.Control
 			b.Kind = BlockMIPSNE
 			b.SetControl(cond)
@@ -9659,11 +9584,7 @@ func rewriteBlockMIPS(b *Block) bool {
 		// match: (LEZ (MOVWconst [c]) yes no)
 		// cond: int32(c) <= 0
 		// result: (First nil yes no)
-		for {
+		for v.Op == OpMIPSMOVWconst {
-			v := b.Control
-			if v.Op != OpMIPSMOVWconst {
-				break
-			}
 			c := v.AuxInt
 			if !(int32(c) <= 0) {
 				break
@@ -9676,11 +9597,7 @@ func rewriteBlockMIPS(b *Block) bool {
 		// match: (LEZ (MOVWconst [c]) yes no)
 		// cond: int32(c) > 0
 		// result: (First nil no yes)
-		for {
+		for v.Op == OpMIPSMOVWconst {
-			v := b.Control
-			if v.Op != OpMIPSMOVWconst {
-				break
-			}
 			c := v.AuxInt
 			if !(int32(c) > 0) {
 				break
@@ -9695,11 +9612,7 @@ func rewriteBlockMIPS(b *Block) bool {
 		// match: (LTZ (MOVWconst [c]) yes no)
 		// cond: int32(c) < 0
 		// result: (First nil yes no)
-		for {
+		for v.Op == OpMIPSMOVWconst {
-			v := b.Control
-			if v.Op != OpMIPSMOVWconst {
-				break
-			}
 			c := v.AuxInt
 			if !(int32(c) < 0) {
 				break
@@ -9712,11 +9625,7 @@ func rewriteBlockMIPS(b *Block) bool {
 		// match: (LTZ (MOVWconst [c]) yes no)
 		// cond: int32(c) >= 0
 		// result: (First nil no yes)
-		for {
+		for v.Op == OpMIPSMOVWconst {
-			v := b.Control
-			if v.Op != OpMIPSMOVWconst {
-				break
-			}
 			c := v.AuxInt
 			if !(int32(c) >= 0) {
 				break
@@ -9731,11 +9640,7 @@ func rewriteBlockMIPS(b *Block) bool {
 		// match: (NE (FPFlagTrue cmp) yes no)
 		// cond:
 		// result: (FPT cmp yes no)
-		for {
+		for v.Op == OpMIPSFPFlagTrue {
-			v := b.Control
-			if v.Op != OpMIPSFPFlagTrue {
-				break
-			}
 			cmp := v.Args[0]
 			b.Kind = BlockMIPSFPT
 			b.SetControl(cmp)
@@ -9745,11 +9650,7 @@ func rewriteBlockMIPS(b *Block) bool {
 		// match: (NE (FPFlagFalse cmp) yes no)
 		// cond:
 		// result: (FPF cmp yes no)
-		for {
+		for v.Op == OpMIPSFPFlagFalse {
-			v := b.Control
-			if v.Op != OpMIPSFPFlagFalse {
-				break
-			}
 			cmp := v.Args[0]
 			b.Kind = BlockMIPSFPF
 			b.SetControl(cmp)
@@ -9759,11 +9660,7 @@ func rewriteBlockMIPS(b *Block) bool {
 		// match: (NE (XORconst [1] cmp:(SGT _ _)) yes no)
 		// cond:
 		// result: (EQ cmp yes no)
-		for {
+		for v.Op == OpMIPSXORconst {
-			v := b.Control
-			if v.Op != OpMIPSXORconst {
-				break
-			}
 			if v.AuxInt != 1 {
 				break
 			}
@@ -9780,11 +9677,7 @@ func rewriteBlockMIPS(b *Block) bool {
 		// match: (NE (XORconst [1] cmp:(SGTU _ _)) yes no)
 		// cond:
 		// result: (EQ cmp yes no)
-		for {
+		for v.Op == OpMIPSXORconst {
-			v := b.Control
-			if v.Op != OpMIPSXORconst {
-				break
-			}
 			if v.AuxInt != 1 {
 				break
 			}
@@ -9801,11 +9694,7 @@ func rewriteBlockMIPS(b *Block) bool {
 		// match: (NE (XORconst [1] cmp:(SGTconst _)) yes no)
 		// cond:
 		// result: (EQ cmp yes no)
-		for {
+		for v.Op == OpMIPSXORconst {
-			v := b.Control
-			if v.Op != OpMIPSXORconst {
-				break
-			}
 			if v.AuxInt != 1 {
 				break
 			}
@@ -9821,11 +9710,7 @@ func rewriteBlockMIPS(b *Block) bool {
 		// match: (NE (XORconst [1] cmp:(SGTUconst _)) yes no)
 		// cond:
 		// result: (EQ cmp yes no)
-		for {
+		for v.Op == OpMIPSXORconst {
-			v := b.Control
-			if v.Op != OpMIPSXORconst {
-				break
-			}
 			if v.AuxInt != 1 {
 				break
 			}
@@ -9841,11 +9726,7 @@ func rewriteBlockMIPS(b *Block) bool {
 		// match: (NE (XORconst [1] cmp:(SGTzero _)) yes no)
 		// cond:
 		// result: (EQ cmp yes no)
-		for {
+		for v.Op == OpMIPSXORconst {
-			v := b.Control
-			if v.Op != OpMIPSXORconst {
-				break
-			}
 			if v.AuxInt != 1 {
 				break
 			}
@@ -9861,11 +9742,7 @@ func rewriteBlockMIPS(b *Block) bool {
 		// match: (NE (XORconst [1] cmp:(SGTUzero _)) yes no)
 		// cond:
 		// result: (EQ cmp yes no)
-		for {
+		for v.Op == OpMIPSXORconst {
-			v := b.Control
-			if v.Op != OpMIPSXORconst {
-				break
-			}
 			if v.AuxInt != 1 {
 				break
 			}
@@ -9881,11 +9758,7 @@ func rewriteBlockMIPS(b *Block) bool {
 		// match: (NE (SGTUconst [1] x) yes no)
 		// cond:
 		// result: (EQ x yes no)
-		for {
+		for v.Op == OpMIPSSGTUconst {
-			v := b.Control
-			if v.Op != OpMIPSSGTUconst {
-				break
-			}
 			if v.AuxInt != 1 {
 				break
 			}
@@ -9898,11 +9771,7 @@ func rewriteBlockMIPS(b *Block) bool {
 		// match: (NE (SGTUzero x) yes no)
 		// cond:
 		// result: (NE x yes no)
-		for {
+		for v.Op == OpMIPSSGTUzero {
-			v := b.Control
-			if v.Op != OpMIPSSGTUzero {
-				break
-			}
 			x := v.Args[0]
 			b.Kind = BlockMIPSNE
 			b.SetControl(x)
@@ -9912,11 +9781,7 @@ func rewriteBlockMIPS(b *Block) bool {
 		// match: (NE (SGTconst [0] x) yes no)
 		// cond:
 		// result: (LTZ x yes no)
-		for {
+		for v.Op == OpMIPSSGTconst {
-			v := b.Control
-			if v.Op != OpMIPSSGTconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -9929,11 +9794,7 @@ func rewriteBlockMIPS(b *Block) bool {
 		// match: (NE (SGTzero x) yes no)
 		// cond:
 		// result: (GTZ x yes no)
-		for {
+		for v.Op == OpMIPSSGTzero {
-			v := b.Control
-			if v.Op != OpMIPSSGTzero {
-				break
-			}
 			x := v.Args[0]
 			b.Kind = BlockMIPSGTZ
 			b.SetControl(x)
@@ -9943,11 +9804,7 @@ func rewriteBlockMIPS(b *Block) bool {
 		// match: (NE (MOVWconst [0]) yes no)
 		// cond:
 		// result: (First nil no yes)
-		for {
+		for v.Op == OpMIPSMOVWconst {
-			v := b.Control
-			if v.Op != OpMIPSMOVWconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -9960,11 +9817,7 @@ func rewriteBlockMIPS(b *Block) bool {
 		// match: (NE (MOVWconst [c]) yes no)
 		// cond: c != 0
 		// result: (First nil yes no)
-		for {
+		for v.Op == OpMIPSMOVWconst {
-			v := b.Control
-			if v.Op != OpMIPSMOVWconst {
-				break
-			}
 			c := v.AuxInt
 			if !(c != 0) {
 				break

src/cmd/compile/internal/ssa/rewriteMIPS64.go

@@ -10036,21 +10036,16 @@ func rewriteValueMIPS64_OpZeroExt8to64_0(v *Value) bool {
 }
 func rewriteBlockMIPS64(b *Block) bool {
 	config := b.Func.Config
-	_ = config
-	fe := b.Func.fe
-	_ = fe
 	typ := &config.Types
 	_ = typ
+	v := b.Control
+	_ = v
 	switch b.Kind {
 	case BlockMIPS64EQ:
 		// match: (EQ (FPFlagTrue cmp) yes no)
 		// cond:
 		// result: (FPF cmp yes no)
-		for {
+		for v.Op == OpMIPS64FPFlagTrue {
-			v := b.Control
-			if v.Op != OpMIPS64FPFlagTrue {
-				break
-			}
 			cmp := v.Args[0]
 			b.Kind = BlockMIPS64FPF
 			b.SetControl(cmp)
@@ -10060,11 +10055,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 		// match: (EQ (FPFlagFalse cmp) yes no)
 		// cond:
 		// result: (FPT cmp yes no)
-		for {
+		for v.Op == OpMIPS64FPFlagFalse {
-			v := b.Control
-			if v.Op != OpMIPS64FPFlagFalse {
-				break
-			}
 			cmp := v.Args[0]
 			b.Kind = BlockMIPS64FPT
 			b.SetControl(cmp)
@@ -10074,11 +10065,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 		// match: (EQ (XORconst [1] cmp:(SGT _ _)) yes no)
 		// cond:
 		// result: (NE cmp yes no)
-		for {
+		for v.Op == OpMIPS64XORconst {
-			v := b.Control
-			if v.Op != OpMIPS64XORconst {
-				break
-			}
 			if v.AuxInt != 1 {
 				break
 			}
@@ -10095,11 +10082,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 		// match: (EQ (XORconst [1] cmp:(SGTU _ _)) yes no)
 		// cond:
 		// result: (NE cmp yes no)
-		for {
+		for v.Op == OpMIPS64XORconst {
-			v := b.Control
-			if v.Op != OpMIPS64XORconst {
-				break
-			}
 			if v.AuxInt != 1 {
 				break
 			}
@@ -10116,11 +10099,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 		// match: (EQ (XORconst [1] cmp:(SGTconst _)) yes no)
 		// cond:
 		// result: (NE cmp yes no)
-		for {
+		for v.Op == OpMIPS64XORconst {
-			v := b.Control
-			if v.Op != OpMIPS64XORconst {
-				break
-			}
 			if v.AuxInt != 1 {
 				break
 			}
@@ -10136,11 +10115,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 		// match: (EQ (XORconst [1] cmp:(SGTUconst _)) yes no)
 		// cond:
 		// result: (NE cmp yes no)
-		for {
+		for v.Op == OpMIPS64XORconst {
-			v := b.Control
-			if v.Op != OpMIPS64XORconst {
-				break
-			}
 			if v.AuxInt != 1 {
 				break
 			}
@@ -10156,11 +10131,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 		// match: (EQ (SGTUconst [1] x) yes no)
 		// cond:
 		// result: (NE x yes no)
-		for {
+		for v.Op == OpMIPS64SGTUconst {
-			v := b.Control
-			if v.Op != OpMIPS64SGTUconst {
-				break
-			}
 			if v.AuxInt != 1 {
 				break
 			}
@@ -10173,11 +10144,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 		// match: (EQ (SGTU x (MOVVconst [0])) yes no)
 		// cond:
 		// result: (EQ x yes no)
-		for {
+		for v.Op == OpMIPS64SGTU {
-			v := b.Control
-			if v.Op != OpMIPS64SGTU {
-				break
-			}
 			_ = v.Args[1]
 			x := v.Args[0]
 			v_1 := v.Args[1]
@@ -10195,11 +10162,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 		// match: (EQ (SGTconst [0] x) yes no)
 		// cond:
 		// result: (GEZ x yes no)
-		for {
+		for v.Op == OpMIPS64SGTconst {
-			v := b.Control
-			if v.Op != OpMIPS64SGTconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -10212,11 +10175,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 		// match: (EQ (SGT x (MOVVconst [0])) yes no)
 		// cond:
 		// result: (LEZ x yes no)
-		for {
+		for v.Op == OpMIPS64SGT {
-			v := b.Control
-			if v.Op != OpMIPS64SGT {
-				break
-			}
 			_ = v.Args[1]
 			x := v.Args[0]
 			v_1 := v.Args[1]
@@ -10234,11 +10193,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 		// match: (EQ (MOVVconst [0]) yes no)
 		// cond:
 		// result: (First nil yes no)
-		for {
+		for v.Op == OpMIPS64MOVVconst {
-			v := b.Control
-			if v.Op != OpMIPS64MOVVconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -10250,11 +10205,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 		// match: (EQ (MOVVconst [c]) yes no)
 		// cond: c != 0
 		// result: (First nil no yes)
-		for {
+		for v.Op == OpMIPS64MOVVconst {
-			v := b.Control
-			if v.Op != OpMIPS64MOVVconst {
-				break
-			}
 			c := v.AuxInt
 			if !(c != 0) {
 				break
@@ -10269,11 +10220,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 		// match: (GEZ (MOVVconst [c]) yes no)
 		// cond: c >= 0
 		// result: (First nil yes no)
-		for {
+		for v.Op == OpMIPS64MOVVconst {
-			v := b.Control
-			if v.Op != OpMIPS64MOVVconst {
-				break
-			}
 			c := v.AuxInt
 			if !(c >= 0) {
 				break
@@ -10286,11 +10233,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 		// match: (GEZ (MOVVconst [c]) yes no)
 		// cond: c < 0
 		// result: (First nil no yes)
-		for {
+		for v.Op == OpMIPS64MOVVconst {
-			v := b.Control
-			if v.Op != OpMIPS64MOVVconst {
-				break
-			}
 			c := v.AuxInt
 			if !(c < 0) {
 				break
@@ -10305,11 +10248,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 		// match: (GTZ (MOVVconst [c]) yes no)
 		// cond: c > 0
 		// result: (First nil yes no)
-		for {
+		for v.Op == OpMIPS64MOVVconst {
-			v := b.Control
-			if v.Op != OpMIPS64MOVVconst {
-				break
-			}
 			c := v.AuxInt
 			if !(c > 0) {
 				break
@@ -10322,11 +10261,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 		// match: (GTZ (MOVVconst [c]) yes no)
 		// cond: c <= 0
 		// result: (First nil no yes)
-		for {
+		for v.Op == OpMIPS64MOVVconst {
-			v := b.Control
-			if v.Op != OpMIPS64MOVVconst {
-				break
-			}
 			c := v.AuxInt
 			if !(c <= 0) {
 				break
@@ -10342,8 +10277,6 @@ func rewriteBlockMIPS64(b *Block) bool {
 		// cond:
 		// result: (NE cond yes no)
 		for {
-			v := b.Control
-			_ = v
 			cond := b.Control
 			b.Kind = BlockMIPS64NE
 			b.SetControl(cond)
@@ -10354,11 +10287,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 		// match: (LEZ (MOVVconst [c]) yes no)
 		// cond: c <= 0
 		// result: (First nil yes no)
-		for {
+		for v.Op == OpMIPS64MOVVconst {
-			v := b.Control
-			if v.Op != OpMIPS64MOVVconst {
-				break
-			}
 			c := v.AuxInt
 			if !(c <= 0) {
 				break
@@ -10371,11 +10300,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 		// match: (LEZ (MOVVconst [c]) yes no)
 		// cond: c > 0
 		// result: (First nil no yes)
-		for {
+		for v.Op == OpMIPS64MOVVconst {
-			v := b.Control
-			if v.Op != OpMIPS64MOVVconst {
-				break
-			}
 			c := v.AuxInt
 			if !(c > 0) {
 				break
@@ -10390,11 +10315,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 		// match: (LTZ (MOVVconst [c]) yes no)
 		// cond: c < 0
 		// result: (First nil yes no)
-		for {
+		for v.Op == OpMIPS64MOVVconst {
-			v := b.Control
-			if v.Op != OpMIPS64MOVVconst {
-				break
-			}
 			c := v.AuxInt
 			if !(c < 0) {
 				break
@@ -10407,11 +10328,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 		// match: (LTZ (MOVVconst [c]) yes no)
 		// cond: c >= 0
 		// result: (First nil no yes)
-		for {
+		for v.Op == OpMIPS64MOVVconst {
-			v := b.Control
-			if v.Op != OpMIPS64MOVVconst {
-				break
-			}
 			c := v.AuxInt
 			if !(c >= 0) {
 				break
@@ -10426,11 +10343,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 		// match: (NE (FPFlagTrue cmp) yes no)
 		// cond:
 		// result: (FPT cmp yes no)
-		for {
+		for v.Op == OpMIPS64FPFlagTrue {
-			v := b.Control
-			if v.Op != OpMIPS64FPFlagTrue {
-				break
-			}
 			cmp := v.Args[0]
 			b.Kind = BlockMIPS64FPT
 			b.SetControl(cmp)
@@ -10440,11 +10353,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 		// match: (NE (FPFlagFalse cmp) yes no)
 		// cond:
 		// result: (FPF cmp yes no)
-		for {
+		for v.Op == OpMIPS64FPFlagFalse {
-			v := b.Control
-			if v.Op != OpMIPS64FPFlagFalse {
-				break
-			}
 			cmp := v.Args[0]
 			b.Kind = BlockMIPS64FPF
 			b.SetControl(cmp)
@@ -10454,11 +10363,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 		// match: (NE (XORconst [1] cmp:(SGT _ _)) yes no)
 		// cond:
 		// result: (EQ cmp yes no)
-		for {
+		for v.Op == OpMIPS64XORconst {
-			v := b.Control
-			if v.Op != OpMIPS64XORconst {
-				break
-			}
 			if v.AuxInt != 1 {
 				break
 			}
@@ -10475,11 +10380,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 		// match: (NE (XORconst [1] cmp:(SGTU _ _)) yes no)
 		// cond:
 		// result: (EQ cmp yes no)
-		for {
+		for v.Op == OpMIPS64XORconst {
-			v := b.Control
-			if v.Op != OpMIPS64XORconst {
-				break
-			}
 			if v.AuxInt != 1 {
 				break
 			}
@@ -10496,11 +10397,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 		// match: (NE (XORconst [1] cmp:(SGTconst _)) yes no)
 		// cond:
 		// result: (EQ cmp yes no)
-		for {
+		for v.Op == OpMIPS64XORconst {
-			v := b.Control
-			if v.Op != OpMIPS64XORconst {
-				break
-			}
 			if v.AuxInt != 1 {
 				break
 			}
@@ -10516,11 +10413,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 		// match: (NE (XORconst [1] cmp:(SGTUconst _)) yes no)
 		// cond:
 		// result: (EQ cmp yes no)
-		for {
+		for v.Op == OpMIPS64XORconst {
-			v := b.Control
-			if v.Op != OpMIPS64XORconst {
-				break
-			}
 			if v.AuxInt != 1 {
 				break
 			}
@@ -10536,11 +10429,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 		// match: (NE (SGTUconst [1] x) yes no)
 		// cond:
 		// result: (EQ x yes no)
-		for {
+		for v.Op == OpMIPS64SGTUconst {
-			v := b.Control
-			if v.Op != OpMIPS64SGTUconst {
-				break
-			}
 			if v.AuxInt != 1 {
 				break
 			}
@@ -10553,11 +10442,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 		// match: (NE (SGTU x (MOVVconst [0])) yes no)
 		// cond:
 		// result: (NE x yes no)
-		for {
+		for v.Op == OpMIPS64SGTU {
-			v := b.Control
-			if v.Op != OpMIPS64SGTU {
-				break
-			}
 			_ = v.Args[1]
 			x := v.Args[0]
 			v_1 := v.Args[1]
@@ -10575,11 +10460,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 		// match: (NE (SGTconst [0] x) yes no)
 		// cond:
 		// result: (LTZ x yes no)
-		for {
+		for v.Op == OpMIPS64SGTconst {
-			v := b.Control
-			if v.Op != OpMIPS64SGTconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -10592,11 +10473,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 		// match: (NE (SGT x (MOVVconst [0])) yes no)
 		// cond:
 		// result: (GTZ x yes no)
-		for {
+		for v.Op == OpMIPS64SGT {
-			v := b.Control
-			if v.Op != OpMIPS64SGT {
-				break
-			}
 			_ = v.Args[1]
 			x := v.Args[0]
 			v_1 := v.Args[1]
@@ -10614,11 +10491,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 		// match: (NE (MOVVconst [0]) yes no)
 		// cond:
 		// result: (First nil no yes)
-		for {
+		for v.Op == OpMIPS64MOVVconst {
-			v := b.Control
-			if v.Op != OpMIPS64MOVVconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -10631,11 +10504,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 		// match: (NE (MOVVconst [c]) yes no)
 		// cond: c != 0
 		// result: (First nil yes no)
-		for {
+		for v.Op == OpMIPS64MOVVconst {
-			v := b.Control
-			if v.Op != OpMIPS64MOVVconst {
-				break
-			}
 			c := v.AuxInt
 			if !(c != 0) {
 				break

src/cmd/compile/internal/ssa/rewritePPC64.go

@@ -30173,21 +30173,16 @@ func rewriteValuePPC64_OpZeroExt8to64_0(v *Value) bool {
 }
 func rewriteBlockPPC64(b *Block) bool {
 	config := b.Func.Config
-	_ = config
-	fe := b.Func.fe
-	_ = fe
 	typ := &config.Types
 	_ = typ
+	v := b.Control
+	_ = v
 	switch b.Kind {
 	case BlockPPC64EQ:
 		// match: (EQ (CMPconst [0] (ANDconst [c] x)) yes no)
 		// cond:
 		// result: (EQ (ANDCCconst [c] x) yes no)
-		for {
+		for v.Op == OpPPC64CMPconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -30208,11 +30203,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (EQ (CMPWconst [0] (ANDconst [c] x)) yes no)
 		// cond:
 		// result: (EQ (ANDCCconst [c] x) yes no)
-		for {
+		for v.Op == OpPPC64CMPWconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPWconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -30233,11 +30224,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (EQ (FlagEQ) yes no)
 		// cond:
 		// result: (First nil yes no)
-		for {
+		for v.Op == OpPPC64FlagEQ {
-			v := b.Control
-			if v.Op != OpPPC64FlagEQ {
-				break
-			}
 			b.Kind = BlockFirst
 			b.SetControl(nil)
 			b.Aux = nil
@@ -30246,11 +30233,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (EQ (FlagLT) yes no)
 		// cond:
 		// result: (First nil no yes)
-		for {
+		for v.Op == OpPPC64FlagLT {
-			v := b.Control
-			if v.Op != OpPPC64FlagLT {
-				break
-			}
 			b.Kind = BlockFirst
 			b.SetControl(nil)
 			b.Aux = nil
@@ -30260,11 +30243,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (EQ (FlagGT) yes no)
 		// cond:
 		// result: (First nil no yes)
-		for {
+		for v.Op == OpPPC64FlagGT {
-			v := b.Control
-			if v.Op != OpPPC64FlagGT {
-				break
-			}
 			b.Kind = BlockFirst
 			b.SetControl(nil)
 			b.Aux = nil
@@ -30274,11 +30253,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (EQ (InvertFlags cmp) yes no)
 		// cond:
 		// result: (EQ cmp yes no)
-		for {
+		for v.Op == OpPPC64InvertFlags {
-			v := b.Control
-			if v.Op != OpPPC64InvertFlags {
-				break
-			}
 			cmp := v.Args[0]
 			b.Kind = BlockPPC64EQ
 			b.SetControl(cmp)
@@ -30288,11 +30263,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (EQ (CMPconst [0] (ANDconst [c] x)) yes no)
 		// cond:
 		// result: (EQ (ANDCCconst [c] x) yes no)
-		for {
+		for v.Op == OpPPC64CMPconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -30313,11 +30284,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (EQ (CMPWconst [0] (ANDconst [c] x)) yes no)
 		// cond:
 		// result: (EQ (ANDCCconst [c] x) yes no)
-		for {
+		for v.Op == OpPPC64CMPWconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPWconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -30338,11 +30305,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (EQ (CMPconst [0] z:(AND x y)) yes no)
 		// cond: z.Uses == 1
 		// result: (EQ (ANDCC x y) yes no)
-		for {
+		for v.Op == OpPPC64CMPconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -30366,11 +30329,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (EQ (CMPconst [0] z:(OR x y)) yes no)
 		// cond: z.Uses == 1
 		// result: (EQ (ORCC x y) yes no)
-		for {
+		for v.Op == OpPPC64CMPconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -30394,11 +30353,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (EQ (CMPconst [0] z:(XOR x y)) yes no)
 		// cond: z.Uses == 1
 		// result: (EQ (XORCC x y) yes no)
-		for {
+		for v.Op == OpPPC64CMPconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -30423,11 +30378,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (GE (FlagEQ) yes no)
 		// cond:
 		// result: (First nil yes no)
-		for {
+		for v.Op == OpPPC64FlagEQ {
-			v := b.Control
-			if v.Op != OpPPC64FlagEQ {
-				break
-			}
 			b.Kind = BlockFirst
 			b.SetControl(nil)
 			b.Aux = nil
@@ -30436,11 +30387,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (GE (FlagLT) yes no)
 		// cond:
 		// result: (First nil no yes)
-		for {
+		for v.Op == OpPPC64FlagLT {
-			v := b.Control
-			if v.Op != OpPPC64FlagLT {
-				break
-			}
 			b.Kind = BlockFirst
 			b.SetControl(nil)
 			b.Aux = nil
@@ -30450,11 +30397,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (GE (FlagGT) yes no)
 		// cond:
 		// result: (First nil yes no)
-		for {
+		for v.Op == OpPPC64FlagGT {
-			v := b.Control
-			if v.Op != OpPPC64FlagGT {
-				break
-			}
 			b.Kind = BlockFirst
 			b.SetControl(nil)
 			b.Aux = nil
@@ -30463,11 +30406,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (GE (InvertFlags cmp) yes no)
 		// cond:
 		// result: (LE cmp yes no)
-		for {
+		for v.Op == OpPPC64InvertFlags {
-			v := b.Control
-			if v.Op != OpPPC64InvertFlags {
-				break
-			}
 			cmp := v.Args[0]
 			b.Kind = BlockPPC64LE
 			b.SetControl(cmp)
@@ -30477,11 +30416,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (GE (CMPconst [0] (ANDconst [c] x)) yes no)
 		// cond:
 		// result: (GE (ANDCCconst [c] x) yes no)
-		for {
+		for v.Op == OpPPC64CMPconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -30502,11 +30437,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (GE (CMPWconst [0] (ANDconst [c] x)) yes no)
 		// cond:
 		// result: (GE (ANDCCconst [c] x) yes no)
-		for {
+		for v.Op == OpPPC64CMPWconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPWconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -30527,11 +30458,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (GE (CMPconst [0] z:(AND x y)) yes no)
 		// cond: z.Uses == 1
 		// result: (GE (ANDCC x y) yes no)
-		for {
+		for v.Op == OpPPC64CMPconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -30555,11 +30482,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (GE (CMPconst [0] z:(OR x y)) yes no)
 		// cond: z.Uses == 1
 		// result: (GE (ORCC x y) yes no)
-		for {
+		for v.Op == OpPPC64CMPconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -30583,11 +30506,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (GE (CMPconst [0] z:(XOR x y)) yes no)
 		// cond: z.Uses == 1
 		// result: (GE (XORCC x y) yes no)
-		for {
+		for v.Op == OpPPC64CMPconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -30612,11 +30531,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (GT (FlagEQ) yes no)
 		// cond:
 		// result: (First nil no yes)
-		for {
+		for v.Op == OpPPC64FlagEQ {
-			v := b.Control
-			if v.Op != OpPPC64FlagEQ {
-				break
-			}
 			b.Kind = BlockFirst
 			b.SetControl(nil)
 			b.Aux = nil
@@ -30626,11 +30541,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (GT (FlagLT) yes no)
 		// cond:
 		// result: (First nil no yes)
-		for {
+		for v.Op == OpPPC64FlagLT {
-			v := b.Control
-			if v.Op != OpPPC64FlagLT {
-				break
-			}
 			b.Kind = BlockFirst
 			b.SetControl(nil)
 			b.Aux = nil
@@ -30640,11 +30551,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (GT (FlagGT) yes no)
 		// cond:
 		// result: (First nil yes no)
-		for {
+		for v.Op == OpPPC64FlagGT {
-			v := b.Control
-			if v.Op != OpPPC64FlagGT {
-				break
-			}
 			b.Kind = BlockFirst
 			b.SetControl(nil)
 			b.Aux = nil
@@ -30653,11 +30560,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (GT (InvertFlags cmp) yes no)
 		// cond:
 		// result: (LT cmp yes no)
-		for {
+		for v.Op == OpPPC64InvertFlags {
-			v := b.Control
-			if v.Op != OpPPC64InvertFlags {
-				break
-			}
 			cmp := v.Args[0]
 			b.Kind = BlockPPC64LT
 			b.SetControl(cmp)
@@ -30667,11 +30570,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (GT (CMPconst [0] (ANDconst [c] x)) yes no)
 		// cond:
 		// result: (GT (ANDCCconst [c] x) yes no)
-		for {
+		for v.Op == OpPPC64CMPconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -30692,11 +30591,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (GT (CMPWconst [0] (ANDconst [c] x)) yes no)
 		// cond:
 		// result: (GT (ANDCCconst [c] x) yes no)
-		for {
+		for v.Op == OpPPC64CMPWconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPWconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -30717,11 +30612,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (GT (CMPconst [0] z:(AND x y)) yes no)
 		// cond: z.Uses == 1
 		// result: (GT (ANDCC x y) yes no)
-		for {
+		for v.Op == OpPPC64CMPconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -30745,11 +30636,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (GT (CMPconst [0] z:(OR x y)) yes no)
 		// cond: z.Uses == 1
 		// result: (GT (ORCC x y) yes no)
-		for {
+		for v.Op == OpPPC64CMPconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -30773,11 +30660,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (GT (CMPconst [0] z:(XOR x y)) yes no)
 		// cond: z.Uses == 1
 		// result: (GT (XORCC x y) yes no)
-		for {
+		for v.Op == OpPPC64CMPconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -30802,11 +30685,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (If (Equal cc) yes no)
 		// cond:
 		// result: (EQ cc yes no)
-		for {
+		for v.Op == OpPPC64Equal {
-			v := b.Control
-			if v.Op != OpPPC64Equal {
-				break
-			}
 			cc := v.Args[0]
 			b.Kind = BlockPPC64EQ
 			b.SetControl(cc)
@@ -30816,11 +30695,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (If (NotEqual cc) yes no)
 		// cond:
 		// result: (NE cc yes no)
-		for {
+		for v.Op == OpPPC64NotEqual {
-			v := b.Control
-			if v.Op != OpPPC64NotEqual {
-				break
-			}
 			cc := v.Args[0]
 			b.Kind = BlockPPC64NE
 			b.SetControl(cc)
@@ -30830,11 +30705,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (If (LessThan cc) yes no)
 		// cond:
 		// result: (LT cc yes no)
-		for {
+		for v.Op == OpPPC64LessThan {
-			v := b.Control
-			if v.Op != OpPPC64LessThan {
-				break
-			}
 			cc := v.Args[0]
 			b.Kind = BlockPPC64LT
 			b.SetControl(cc)
@@ -30844,11 +30715,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (If (LessEqual cc) yes no)
 		// cond:
 		// result: (LE cc yes no)
-		for {
+		for v.Op == OpPPC64LessEqual {
-			v := b.Control
-			if v.Op != OpPPC64LessEqual {
-				break
-			}
 			cc := v.Args[0]
 			b.Kind = BlockPPC64LE
 			b.SetControl(cc)
@@ -30858,11 +30725,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (If (GreaterThan cc) yes no)
 		// cond:
 		// result: (GT cc yes no)
-		for {
+		for v.Op == OpPPC64GreaterThan {
-			v := b.Control
-			if v.Op != OpPPC64GreaterThan {
-				break
-			}
 			cc := v.Args[0]
 			b.Kind = BlockPPC64GT
 			b.SetControl(cc)
@@ -30872,11 +30735,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (If (GreaterEqual cc) yes no)
 		// cond:
 		// result: (GE cc yes no)
-		for {
+		for v.Op == OpPPC64GreaterEqual {
-			v := b.Control
-			if v.Op != OpPPC64GreaterEqual {
-				break
-			}
 			cc := v.Args[0]
 			b.Kind = BlockPPC64GE
 			b.SetControl(cc)
@@ -30886,11 +30745,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (If (FLessThan cc) yes no)
 		// cond:
 		// result: (FLT cc yes no)
-		for {
+		for v.Op == OpPPC64FLessThan {
-			v := b.Control
-			if v.Op != OpPPC64FLessThan {
-				break
-			}
 			cc := v.Args[0]
 			b.Kind = BlockPPC64FLT
 			b.SetControl(cc)
@@ -30900,11 +30755,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (If (FLessEqual cc) yes no)
 		// cond:
 		// result: (FLE cc yes no)
-		for {
+		for v.Op == OpPPC64FLessEqual {
-			v := b.Control
-			if v.Op != OpPPC64FLessEqual {
-				break
-			}
 			cc := v.Args[0]
 			b.Kind = BlockPPC64FLE
 			b.SetControl(cc)
@@ -30914,11 +30765,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (If (FGreaterThan cc) yes no)
 		// cond:
 		// result: (FGT cc yes no)
-		for {
+		for v.Op == OpPPC64FGreaterThan {
-			v := b.Control
-			if v.Op != OpPPC64FGreaterThan {
-				break
-			}
 			cc := v.Args[0]
 			b.Kind = BlockPPC64FGT
 			b.SetControl(cc)
@@ -30928,11 +30775,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (If (FGreaterEqual cc) yes no)
 		// cond:
 		// result: (FGE cc yes no)
-		for {
+		for v.Op == OpPPC64FGreaterEqual {
-			v := b.Control
-			if v.Op != OpPPC64FGreaterEqual {
-				break
-			}
 			cc := v.Args[0]
 			b.Kind = BlockPPC64FGE
 			b.SetControl(cc)
@@ -30943,8 +30786,6 @@ func rewriteBlockPPC64(b *Block) bool {
 		// cond:
 		// result: (NE (CMPWconst [0] cond) yes no)
 		for {
-			v := b.Control
-			_ = v
 			cond := b.Control
 			b.Kind = BlockPPC64NE
 			v0 := b.NewValue0(v.Pos, OpPPC64CMPWconst, types.TypeFlags)
@@ -30958,11 +30799,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (LE (FlagEQ) yes no)
 		// cond:
 		// result: (First nil yes no)
-		for {
+		for v.Op == OpPPC64FlagEQ {
-			v := b.Control
-			if v.Op != OpPPC64FlagEQ {
-				break
-			}
 			b.Kind = BlockFirst
 			b.SetControl(nil)
 			b.Aux = nil
@@ -30971,11 +30808,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (LE (FlagLT) yes no)
 		// cond:
 		// result: (First nil yes no)
-		for {
+		for v.Op == OpPPC64FlagLT {
-			v := b.Control
-			if v.Op != OpPPC64FlagLT {
-				break
-			}
 			b.Kind = BlockFirst
 			b.SetControl(nil)
 			b.Aux = nil
@@ -30984,11 +30817,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (LE (FlagGT) yes no)
 		// cond:
 		// result: (First nil no yes)
-		for {
+		for v.Op == OpPPC64FlagGT {
-			v := b.Control
-			if v.Op != OpPPC64FlagGT {
-				break
-			}
 			b.Kind = BlockFirst
 			b.SetControl(nil)
 			b.Aux = nil
@@ -30998,11 +30827,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (LE (InvertFlags cmp) yes no)
 		// cond:
 		// result: (GE cmp yes no)
-		for {
+		for v.Op == OpPPC64InvertFlags {
-			v := b.Control
-			if v.Op != OpPPC64InvertFlags {
-				break
-			}
 			cmp := v.Args[0]
 			b.Kind = BlockPPC64GE
 			b.SetControl(cmp)
@@ -31012,11 +30837,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (LE (CMPconst [0] (ANDconst [c] x)) yes no)
 		// cond:
 		// result: (LE (ANDCCconst [c] x) yes no)
-		for {
+		for v.Op == OpPPC64CMPconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -31037,11 +30858,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (LE (CMPWconst [0] (ANDconst [c] x)) yes no)
 		// cond:
 		// result: (LE (ANDCCconst [c] x) yes no)
-		for {
+		for v.Op == OpPPC64CMPWconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPWconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -31062,11 +30879,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (LE (CMPconst [0] z:(AND x y)) yes no)
 		// cond: z.Uses == 1
 		// result: (LE (ANDCC x y) yes no)
-		for {
+		for v.Op == OpPPC64CMPconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -31090,11 +30903,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (LE (CMPconst [0] z:(OR x y)) yes no)
 		// cond: z.Uses == 1
 		// result: (LE (ORCC x y) yes no)
-		for {
+		for v.Op == OpPPC64CMPconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -31118,11 +30927,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (LE (CMPconst [0] z:(XOR x y)) yes no)
 		// cond: z.Uses == 1
 		// result: (LE (XORCC x y) yes no)
-		for {
+		for v.Op == OpPPC64CMPconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -31147,11 +30952,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (LT (FlagEQ) yes no)
 		// cond:
 		// result: (First nil no yes)
-		for {
+		for v.Op == OpPPC64FlagEQ {
-			v := b.Control
-			if v.Op != OpPPC64FlagEQ {
-				break
-			}
 			b.Kind = BlockFirst
 			b.SetControl(nil)
 			b.Aux = nil
@@ -31161,11 +30962,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (LT (FlagLT) yes no)
 		// cond:
 		// result: (First nil yes no)
-		for {
+		for v.Op == OpPPC64FlagLT {
-			v := b.Control
-			if v.Op != OpPPC64FlagLT {
-				break
-			}
 			b.Kind = BlockFirst
 			b.SetControl(nil)
 			b.Aux = nil
@@ -31174,11 +30971,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (LT (FlagGT) yes no)
 		// cond:
 		// result: (First nil no yes)
-		for {
+		for v.Op == OpPPC64FlagGT {
-			v := b.Control
-			if v.Op != OpPPC64FlagGT {
-				break
-			}
 			b.Kind = BlockFirst
 			b.SetControl(nil)
 			b.Aux = nil
@@ -31188,11 +30981,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (LT (InvertFlags cmp) yes no)
 		// cond:
 		// result: (GT cmp yes no)
-		for {
+		for v.Op == OpPPC64InvertFlags {
-			v := b.Control
-			if v.Op != OpPPC64InvertFlags {
-				break
-			}
 			cmp := v.Args[0]
 			b.Kind = BlockPPC64GT
 			b.SetControl(cmp)
@@ -31202,11 +30991,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (LT (CMPconst [0] (ANDconst [c] x)) yes no)
 		// cond:
 		// result: (LT (ANDCCconst [c] x) yes no)
-		for {
+		for v.Op == OpPPC64CMPconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -31227,11 +31012,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (LT (CMPWconst [0] (ANDconst [c] x)) yes no)
 		// cond:
 		// result: (LT (ANDCCconst [c] x) yes no)
-		for {
+		for v.Op == OpPPC64CMPWconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPWconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -31252,11 +31033,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (LT (CMPconst [0] z:(AND x y)) yes no)
 		// cond: z.Uses == 1
 		// result: (LT (ANDCC x y) yes no)
-		for {
+		for v.Op == OpPPC64CMPconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -31280,11 +31057,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (LT (CMPconst [0] z:(OR x y)) yes no)
 		// cond: z.Uses == 1
 		// result: (LT (ORCC x y) yes no)
-		for {
+		for v.Op == OpPPC64CMPconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -31308,11 +31081,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (LT (CMPconst [0] z:(XOR x y)) yes no)
 		// cond: z.Uses == 1
 		// result: (LT (XORCC x y) yes no)
-		for {
+		for v.Op == OpPPC64CMPconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -31337,11 +31106,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (NE (CMPWconst [0] (Equal cc)) yes no)
 		// cond:
 		// result: (EQ cc yes no)
-		for {
+		for v.Op == OpPPC64CMPWconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPWconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -31358,11 +31123,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (NE (CMPWconst [0] (NotEqual cc)) yes no)
 		// cond:
 		// result: (NE cc yes no)
-		for {
+		for v.Op == OpPPC64CMPWconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPWconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -31379,11 +31140,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (NE (CMPWconst [0] (LessThan cc)) yes no)
 		// cond:
 		// result: (LT cc yes no)
-		for {
+		for v.Op == OpPPC64CMPWconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPWconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -31400,11 +31157,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (NE (CMPWconst [0] (LessEqual cc)) yes no)
 		// cond:
 		// result: (LE cc yes no)
-		for {
+		for v.Op == OpPPC64CMPWconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPWconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -31421,11 +31174,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (NE (CMPWconst [0] (GreaterThan cc)) yes no)
 		// cond:
 		// result: (GT cc yes no)
-		for {
+		for v.Op == OpPPC64CMPWconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPWconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -31442,11 +31191,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (NE (CMPWconst [0] (GreaterEqual cc)) yes no)
 		// cond:
 		// result: (GE cc yes no)
-		for {
+		for v.Op == OpPPC64CMPWconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPWconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -31463,11 +31208,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (NE (CMPWconst [0] (FLessThan cc)) yes no)
 		// cond:
 		// result: (FLT cc yes no)
-		for {
+		for v.Op == OpPPC64CMPWconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPWconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -31484,11 +31225,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (NE (CMPWconst [0] (FLessEqual cc)) yes no)
 		// cond:
 		// result: (FLE cc yes no)
-		for {
+		for v.Op == OpPPC64CMPWconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPWconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -31505,11 +31242,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (NE (CMPWconst [0] (FGreaterThan cc)) yes no)
 		// cond:
 		// result: (FGT cc yes no)
-		for {
+		for v.Op == OpPPC64CMPWconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPWconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -31526,11 +31259,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (NE (CMPWconst [0] (FGreaterEqual cc)) yes no)
 		// cond:
 		// result: (FGE cc yes no)
-		for {
+		for v.Op == OpPPC64CMPWconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPWconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -31547,11 +31276,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (NE (CMPconst [0] (ANDconst [c] x)) yes no)
 		// cond:
 		// result: (NE (ANDCCconst [c] x) yes no)
-		for {
+		for v.Op == OpPPC64CMPconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -31572,11 +31297,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (NE (CMPWconst [0] (ANDconst [c] x)) yes no)
 		// cond:
 		// result: (NE (ANDCCconst [c] x) yes no)
-		for {
+		for v.Op == OpPPC64CMPWconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPWconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -31597,11 +31318,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (NE (FlagEQ) yes no)
 		// cond:
 		// result: (First nil no yes)
-		for {
+		for v.Op == OpPPC64FlagEQ {
-			v := b.Control
-			if v.Op != OpPPC64FlagEQ {
-				break
-			}
 			b.Kind = BlockFirst
 			b.SetControl(nil)
 			b.Aux = nil
@@ -31611,11 +31328,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (NE (FlagLT) yes no)
 		// cond:
 		// result: (First nil yes no)
-		for {
+		for v.Op == OpPPC64FlagLT {
-			v := b.Control
-			if v.Op != OpPPC64FlagLT {
-				break
-			}
 			b.Kind = BlockFirst
 			b.SetControl(nil)
 			b.Aux = nil
@@ -31624,11 +31337,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (NE (FlagGT) yes no)
 		// cond:
 		// result: (First nil yes no)
-		for {
+		for v.Op == OpPPC64FlagGT {
-			v := b.Control
-			if v.Op != OpPPC64FlagGT {
-				break
-			}
 			b.Kind = BlockFirst
 			b.SetControl(nil)
 			b.Aux = nil
@@ -31637,11 +31346,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (NE (InvertFlags cmp) yes no)
 		// cond:
 		// result: (NE cmp yes no)
-		for {
+		for v.Op == OpPPC64InvertFlags {
-			v := b.Control
-			if v.Op != OpPPC64InvertFlags {
-				break
-			}
 			cmp := v.Args[0]
 			b.Kind = BlockPPC64NE
 			b.SetControl(cmp)
@@ -31651,11 +31356,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (NE (CMPconst [0] (ANDconst [c] x)) yes no)
 		// cond:
 		// result: (NE (ANDCCconst [c] x) yes no)
-		for {
+		for v.Op == OpPPC64CMPconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -31676,11 +31377,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (NE (CMPWconst [0] (ANDconst [c] x)) yes no)
 		// cond:
 		// result: (NE (ANDCCconst [c] x) yes no)
-		for {
+		for v.Op == OpPPC64CMPWconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPWconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -31701,11 +31398,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (NE (CMPconst [0] z:(AND x y)) yes no)
 		// cond: z.Uses == 1
 		// result: (NE (ANDCC x y) yes no)
-		for {
+		for v.Op == OpPPC64CMPconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -31729,11 +31422,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (NE (CMPconst [0] z:(OR x y)) yes no)
 		// cond: z.Uses == 1
 		// result: (NE (ORCC x y) yes no)
-		for {
+		for v.Op == OpPPC64CMPconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -31757,11 +31446,7 @@ func rewriteBlockPPC64(b *Block) bool {
 		// match: (NE (CMPconst [0] z:(XOR x y)) yes no)
 		// cond: z.Uses == 1
 		// result: (NE (XORCC x y) yes no)
-		for {
+		for v.Op == OpPPC64CMPconst {
-			v := b.Control
-			if v.Op != OpPPC64CMPconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}

src/cmd/compile/internal/ssa/rewriteS390X.go

@@ -40897,21 +40897,16 @@ func rewriteValueS390X_OpZeroExt8to64_0(v *Value) bool {
 }
 func rewriteBlockS390X(b *Block) bool {
 	config := b.Func.Config
-	_ = config
-	fe := b.Func.fe
-	_ = fe
 	typ := &config.Types
 	_ = typ
+	v := b.Control
+	_ = v
 	switch b.Kind {
 	case BlockS390XEQ:
 		// match: (EQ (InvertFlags cmp) yes no)
 		// cond:
 		// result: (EQ cmp yes no)
-		for {
+		for v.Op == OpS390XInvertFlags {
-			v := b.Control
-			if v.Op != OpS390XInvertFlags {
-				break
-			}
 			cmp := v.Args[0]
 			b.Kind = BlockS390XEQ
 			b.SetControl(cmp)
@@ -40921,11 +40916,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (EQ (FlagEQ) yes no)
 		// cond:
 		// result: (First nil yes no)
-		for {
+		for v.Op == OpS390XFlagEQ {
-			v := b.Control
-			if v.Op != OpS390XFlagEQ {
-				break
-			}
 			b.Kind = BlockFirst
 			b.SetControl(nil)
 			b.Aux = nil
@@ -40934,11 +40925,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (EQ (FlagLT) yes no)
 		// cond:
 		// result: (First nil no yes)
-		for {
+		for v.Op == OpS390XFlagLT {
-			v := b.Control
-			if v.Op != OpS390XFlagLT {
-				break
-			}
 			b.Kind = BlockFirst
 			b.SetControl(nil)
 			b.Aux = nil
@@ -40948,11 +40935,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (EQ (FlagGT) yes no)
 		// cond:
 		// result: (First nil no yes)
-		for {
+		for v.Op == OpS390XFlagGT {
-			v := b.Control
-			if v.Op != OpS390XFlagGT {
-				break
-			}
 			b.Kind = BlockFirst
 			b.SetControl(nil)
 			b.Aux = nil
@@ -40963,11 +40946,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (GE (InvertFlags cmp) yes no)
 		// cond:
 		// result: (LE cmp yes no)
-		for {
+		for v.Op == OpS390XInvertFlags {
-			v := b.Control
-			if v.Op != OpS390XInvertFlags {
-				break
-			}
 			cmp := v.Args[0]
 			b.Kind = BlockS390XLE
 			b.SetControl(cmp)
@@ -40977,11 +40956,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (GE (FlagEQ) yes no)
 		// cond:
 		// result: (First nil yes no)
-		for {
+		for v.Op == OpS390XFlagEQ {
-			v := b.Control
-			if v.Op != OpS390XFlagEQ {
-				break
-			}
 			b.Kind = BlockFirst
 			b.SetControl(nil)
 			b.Aux = nil
@@ -40990,11 +40965,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (GE (FlagLT) yes no)
 		// cond:
 		// result: (First nil no yes)
-		for {
+		for v.Op == OpS390XFlagLT {
-			v := b.Control
-			if v.Op != OpS390XFlagLT {
-				break
-			}
 			b.Kind = BlockFirst
 			b.SetControl(nil)
 			b.Aux = nil
@@ -41004,11 +40975,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (GE (FlagGT) yes no)
 		// cond:
 		// result: (First nil yes no)
-		for {
+		for v.Op == OpS390XFlagGT {
-			v := b.Control
-			if v.Op != OpS390XFlagGT {
-				break
-			}
 			b.Kind = BlockFirst
 			b.SetControl(nil)
 			b.Aux = nil
@@ -41018,11 +40985,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (GT (InvertFlags cmp) yes no)
 		// cond:
 		// result: (LT cmp yes no)
-		for {
+		for v.Op == OpS390XInvertFlags {
-			v := b.Control
-			if v.Op != OpS390XInvertFlags {
-				break
-			}
 			cmp := v.Args[0]
 			b.Kind = BlockS390XLT
 			b.SetControl(cmp)
@@ -41032,11 +40995,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (GT (FlagEQ) yes no)
 		// cond:
 		// result: (First nil no yes)
-		for {
+		for v.Op == OpS390XFlagEQ {
-			v := b.Control
-			if v.Op != OpS390XFlagEQ {
-				break
-			}
 			b.Kind = BlockFirst
 			b.SetControl(nil)
 			b.Aux = nil
@@ -41046,11 +41005,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (GT (FlagLT) yes no)
 		// cond:
 		// result: (First nil no yes)
-		for {
+		for v.Op == OpS390XFlagLT {
-			v := b.Control
-			if v.Op != OpS390XFlagLT {
-				break
-			}
 			b.Kind = BlockFirst
 			b.SetControl(nil)
 			b.Aux = nil
@@ -41060,11 +41015,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (GT (FlagGT) yes no)
 		// cond:
 		// result: (First nil yes no)
-		for {
+		for v.Op == OpS390XFlagGT {
-			v := b.Control
-			if v.Op != OpS390XFlagGT {
-				break
-			}
 			b.Kind = BlockFirst
 			b.SetControl(nil)
 			b.Aux = nil
@@ -41074,11 +41025,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (If (MOVDLT (MOVDconst [0]) (MOVDconst [1]) cmp) yes no)
 		// cond:
 		// result: (LT cmp yes no)
-		for {
+		for v.Op == OpS390XMOVDLT {
-			v := b.Control
-			if v.Op != OpS390XMOVDLT {
-				break
-			}
 			cmp := v.Args[2]
 			v_0 := v.Args[0]
 			if v_0.Op != OpS390XMOVDconst {
@@ -41102,11 +41049,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (If (MOVDLE (MOVDconst [0]) (MOVDconst [1]) cmp) yes no)
 		// cond:
 		// result: (LE cmp yes no)
-		for {
+		for v.Op == OpS390XMOVDLE {
-			v := b.Control
-			if v.Op != OpS390XMOVDLE {
-				break
-			}
 			cmp := v.Args[2]
 			v_0 := v.Args[0]
 			if v_0.Op != OpS390XMOVDconst {
@@ -41130,11 +41073,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (If (MOVDGT (MOVDconst [0]) (MOVDconst [1]) cmp) yes no)
 		// cond:
 		// result: (GT cmp yes no)
-		for {
+		for v.Op == OpS390XMOVDGT {
-			v := b.Control
-			if v.Op != OpS390XMOVDGT {
-				break
-			}
 			cmp := v.Args[2]
 			v_0 := v.Args[0]
 			if v_0.Op != OpS390XMOVDconst {
@@ -41158,11 +41097,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (If (MOVDGE (MOVDconst [0]) (MOVDconst [1]) cmp) yes no)
 		// cond:
 		// result: (GE cmp yes no)
-		for {
+		for v.Op == OpS390XMOVDGE {
-			v := b.Control
-			if v.Op != OpS390XMOVDGE {
-				break
-			}
 			cmp := v.Args[2]
 			v_0 := v.Args[0]
 			if v_0.Op != OpS390XMOVDconst {
@@ -41186,11 +41121,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (If (MOVDEQ (MOVDconst [0]) (MOVDconst [1]) cmp) yes no)
 		// cond:
 		// result: (EQ cmp yes no)
-		for {
+		for v.Op == OpS390XMOVDEQ {
-			v := b.Control
-			if v.Op != OpS390XMOVDEQ {
-				break
-			}
 			cmp := v.Args[2]
 			v_0 := v.Args[0]
 			if v_0.Op != OpS390XMOVDconst {
@@ -41214,11 +41145,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (If (MOVDNE (MOVDconst [0]) (MOVDconst [1]) cmp) yes no)
 		// cond:
 		// result: (NE cmp yes no)
-		for {
+		for v.Op == OpS390XMOVDNE {
-			v := b.Control
-			if v.Op != OpS390XMOVDNE {
-				break
-			}
 			cmp := v.Args[2]
 			v_0 := v.Args[0]
 			if v_0.Op != OpS390XMOVDconst {
@@ -41242,11 +41169,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (If (MOVDGTnoinv (MOVDconst [0]) (MOVDconst [1]) cmp) yes no)
 		// cond:
 		// result: (GTF cmp yes no)
-		for {
+		for v.Op == OpS390XMOVDGTnoinv {
-			v := b.Control
-			if v.Op != OpS390XMOVDGTnoinv {
-				break
-			}
 			cmp := v.Args[2]
 			v_0 := v.Args[0]
 			if v_0.Op != OpS390XMOVDconst {
@@ -41270,11 +41193,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (If (MOVDGEnoinv (MOVDconst [0]) (MOVDconst [1]) cmp) yes no)
 		// cond:
 		// result: (GEF cmp yes no)
-		for {
+		for v.Op == OpS390XMOVDGEnoinv {
-			v := b.Control
-			if v.Op != OpS390XMOVDGEnoinv {
-				break
-			}
 			cmp := v.Args[2]
 			v_0 := v.Args[0]
 			if v_0.Op != OpS390XMOVDconst {
@@ -41299,8 +41218,6 @@ func rewriteBlockS390X(b *Block) bool {
 		// cond:
 		// result: (NE (CMPWconst [0] (MOVBZreg <typ.Bool> cond)) yes no)
 		for {
-			v := b.Control
-			_ = v
 			cond := b.Control
 			b.Kind = BlockS390XNE
 			v0 := b.NewValue0(v.Pos, OpS390XCMPWconst, types.TypeFlags)
@@ -41316,11 +41233,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (LE (InvertFlags cmp) yes no)
 		// cond:
 		// result: (GE cmp yes no)
-		for {
+		for v.Op == OpS390XInvertFlags {
-			v := b.Control
-			if v.Op != OpS390XInvertFlags {
-				break
-			}
 			cmp := v.Args[0]
 			b.Kind = BlockS390XGE
 			b.SetControl(cmp)
@@ -41330,11 +41243,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (LE (FlagEQ) yes no)
 		// cond:
 		// result: (First nil yes no)
-		for {
+		for v.Op == OpS390XFlagEQ {
-			v := b.Control
-			if v.Op != OpS390XFlagEQ {
-				break
-			}
 			b.Kind = BlockFirst
 			b.SetControl(nil)
 			b.Aux = nil
@@ -41343,11 +41252,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (LE (FlagLT) yes no)
 		// cond:
 		// result: (First nil yes no)
-		for {
+		for v.Op == OpS390XFlagLT {
-			v := b.Control
-			if v.Op != OpS390XFlagLT {
-				break
-			}
 			b.Kind = BlockFirst
 			b.SetControl(nil)
 			b.Aux = nil
@@ -41356,11 +41261,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (LE (FlagGT) yes no)
 		// cond:
 		// result: (First nil no yes)
-		for {
+		for v.Op == OpS390XFlagGT {
-			v := b.Control
-			if v.Op != OpS390XFlagGT {
-				break
-			}
 			b.Kind = BlockFirst
 			b.SetControl(nil)
 			b.Aux = nil
@@ -41371,11 +41272,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (LT (InvertFlags cmp) yes no)
 		// cond:
 		// result: (GT cmp yes no)
-		for {
+		for v.Op == OpS390XInvertFlags {
-			v := b.Control
-			if v.Op != OpS390XInvertFlags {
-				break
-			}
 			cmp := v.Args[0]
 			b.Kind = BlockS390XGT
 			b.SetControl(cmp)
@@ -41385,11 +41282,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (LT (FlagEQ) yes no)
 		// cond:
 		// result: (First nil no yes)
-		for {
+		for v.Op == OpS390XFlagEQ {
-			v := b.Control
-			if v.Op != OpS390XFlagEQ {
-				break
-			}
 			b.Kind = BlockFirst
 			b.SetControl(nil)
 			b.Aux = nil
@@ -41399,11 +41292,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (LT (FlagLT) yes no)
 		// cond:
 		// result: (First nil yes no)
-		for {
+		for v.Op == OpS390XFlagLT {
-			v := b.Control
-			if v.Op != OpS390XFlagLT {
-				break
-			}
 			b.Kind = BlockFirst
 			b.SetControl(nil)
 			b.Aux = nil
@@ -41412,11 +41301,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (LT (FlagGT) yes no)
 		// cond:
 		// result: (First nil no yes)
-		for {
+		for v.Op == OpS390XFlagGT {
-			v := b.Control
-			if v.Op != OpS390XFlagGT {
-				break
-			}
 			b.Kind = BlockFirst
 			b.SetControl(nil)
 			b.Aux = nil
@@ -41427,11 +41312,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (NE (CMPWconst [0] (MOVDLT (MOVDconst [0]) (MOVDconst [1]) cmp)) yes no)
 		// cond:
 		// result: (LT cmp yes no)
-		for {
+		for v.Op == OpS390XCMPWconst {
-			v := b.Control
-			if v.Op != OpS390XCMPWconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -41462,11 +41343,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (NE (CMPWconst [0] (MOVDLE (MOVDconst [0]) (MOVDconst [1]) cmp)) yes no)
 		// cond:
 		// result: (LE cmp yes no)
-		for {
+		for v.Op == OpS390XCMPWconst {
-			v := b.Control
-			if v.Op != OpS390XCMPWconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -41497,11 +41374,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (NE (CMPWconst [0] (MOVDGT (MOVDconst [0]) (MOVDconst [1]) cmp)) yes no)
 		// cond:
 		// result: (GT cmp yes no)
-		for {
+		for v.Op == OpS390XCMPWconst {
-			v := b.Control
-			if v.Op != OpS390XCMPWconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -41532,11 +41405,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (NE (CMPWconst [0] (MOVDGE (MOVDconst [0]) (MOVDconst [1]) cmp)) yes no)
 		// cond:
 		// result: (GE cmp yes no)
-		for {
+		for v.Op == OpS390XCMPWconst {
-			v := b.Control
-			if v.Op != OpS390XCMPWconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -41567,11 +41436,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (NE (CMPWconst [0] (MOVDEQ (MOVDconst [0]) (MOVDconst [1]) cmp)) yes no)
 		// cond:
 		// result: (EQ cmp yes no)
-		for {
+		for v.Op == OpS390XCMPWconst {
-			v := b.Control
-			if v.Op != OpS390XCMPWconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -41602,11 +41467,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (NE (CMPWconst [0] (MOVDNE (MOVDconst [0]) (MOVDconst [1]) cmp)) yes no)
 		// cond:
 		// result: (NE cmp yes no)
-		for {
+		for v.Op == OpS390XCMPWconst {
-			v := b.Control
-			if v.Op != OpS390XCMPWconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -41637,11 +41498,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (NE (CMPWconst [0] (MOVDGTnoinv (MOVDconst [0]) (MOVDconst [1]) cmp)) yes no)
 		// cond:
 		// result: (GTF cmp yes no)
-		for {
+		for v.Op == OpS390XCMPWconst {
-			v := b.Control
-			if v.Op != OpS390XCMPWconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -41672,11 +41529,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (NE (CMPWconst [0] (MOVDGEnoinv (MOVDconst [0]) (MOVDconst [1]) cmp)) yes no)
 		// cond:
 		// result: (GEF cmp yes no)
-		for {
+		for v.Op == OpS390XCMPWconst {
-			v := b.Control
-			if v.Op != OpS390XCMPWconst {
-				break
-			}
 			if v.AuxInt != 0 {
 				break
 			}
@@ -41707,11 +41560,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (NE (InvertFlags cmp) yes no)
 		// cond:
 		// result: (NE cmp yes no)
-		for {
+		for v.Op == OpS390XInvertFlags {
-			v := b.Control
-			if v.Op != OpS390XInvertFlags {
-				break
-			}
 			cmp := v.Args[0]
 			b.Kind = BlockS390XNE
 			b.SetControl(cmp)
@@ -41721,11 +41570,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (NE (FlagEQ) yes no)
 		// cond:
 		// result: (First nil no yes)
-		for {
+		for v.Op == OpS390XFlagEQ {
-			v := b.Control
-			if v.Op != OpS390XFlagEQ {
-				break
-			}
 			b.Kind = BlockFirst
 			b.SetControl(nil)
 			b.Aux = nil
@@ -41735,11 +41580,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (NE (FlagLT) yes no)
 		// cond:
 		// result: (First nil yes no)
-		for {
+		for v.Op == OpS390XFlagLT {
-			v := b.Control
-			if v.Op != OpS390XFlagLT {
-				break
-			}
 			b.Kind = BlockFirst
 			b.SetControl(nil)
 			b.Aux = nil
@@ -41748,11 +41589,7 @@ func rewriteBlockS390X(b *Block) bool {
 		// match: (NE (FlagGT) yes no)
 		// cond:
 		// result: (First nil yes no)
-		for {
+		for v.Op == OpS390XFlagGT {
-			v := b.Control
-			if v.Op != OpS390XFlagGT {
-				break
-			}
 			b.Kind = BlockFirst
 			b.SetControl(nil)
 			b.Aux = nil

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

@@ -6382,11 +6382,10 @@ func rewriteValueWasm_OpZeroExt8to64_0(v *Value) bool {
 }
 func rewriteBlockWasm(b *Block) bool {
 	config := b.Func.Config
-	_ = config
-	fe := b.Func.fe
-	_ = fe
 	typ := &config.Types
 	_ = typ
+	v := b.Control
+	_ = v
 	switch b.Kind {
 	}
 	return false

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

@@ -493,11 +493,10 @@ func rewriteValuedec_OpStringPtr_0(v *Value) bool {
 }
 func rewriteBlockdec(b *Block) bool {
 	config := b.Func.Config
-	_ = config
-	fe := b.Func.fe
-	_ = fe
 	typ := &config.Types
 	_ = typ
+	v := b.Control
+	_ = v
 	switch b.Kind {
 	}
 	return false

src/cmd/compile/internal/ssa/rewritedec64.go

@@ -2727,11 +2727,10 @@ func rewriteValuedec64_OpZeroExt8to64_0(v *Value) bool {
 }
 func rewriteBlockdec64(b *Block) bool {
 	config := b.Func.Config
-	_ = config
-	fe := b.Func.fe
-	_ = fe
 	typ := &config.Types
 	_ = typ
+	v := b.Control
+	_ = v
 	switch b.Kind {
 	}
 	return false

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

@@ -271,11 +271,10 @@ func rewriteValuedecArgs_OpArg_10(v *Value) bool {
 }
 func rewriteBlockdecArgs(b *Block) bool {
 	config := b.Func.Config
-	_ = config
-	fe := b.Func.fe
-	_ = fe
 	typ := &config.Types
 	_ = typ
+	v := b.Control
+	_ = v
 	switch b.Kind {
 	}
 	return false

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

@@ -32620,21 +32620,16 @@ func rewriteValuegeneric_OpZeroExt8to64_0(v *Value) bool {
 }
 func rewriteBlockgeneric(b *Block) bool {
 	config := b.Func.Config
-	_ = config
-	fe := b.Func.fe
-	_ = fe
 	typ := &config.Types
 	_ = typ
+	v := b.Control
+	_ = v
 	switch b.Kind {
 	case BlockIf:
 		// match: (If (Not cond) yes no)
 		// cond:
 		// result: (If cond no yes)
-		for {
+		for v.Op == OpNot {
-			v := b.Control
-			if v.Op != OpNot {
-				break
-			}
 			cond := v.Args[0]
 			b.Kind = BlockIf
 			b.SetControl(cond)
@@ -32645,11 +32640,7 @@ func rewriteBlockgeneric(b *Block) bool {
 		// match: (If (ConstBool [c]) yes no)
 		// cond: c == 1
 		// result: (First nil yes no)
-		for {
+		for v.Op == OpConstBool {
-			v := b.Control
-			if v.Op != OpConstBool {
-				break
-			}
 			c := v.AuxInt
 			if !(c == 1) {
 				break
@@ -32662,11 +32653,7 @@ func rewriteBlockgeneric(b *Block) bool {
 		// match: (If (ConstBool [c]) yes no)
 		// cond: c == 0
 		// result: (First nil no yes)
-		for {
+		for v.Op == OpConstBool {
-			v := b.Control
-			if v.Op != OpConstBool {
-				break
-			}
 			c := v.AuxInt
 			if !(c == 0) {
 				break