cmd/compile: simplify bounded shift on riscv64

The prove pass will mark some shifts bounded, and then we can use that
information to generate better code on riscv64.

Change-Id: Ia22f43d0598453c9417adac7017db28d7240948b
Reviewed-on: https://go-review.googlesource.com/c/go/+/422616
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Joel Sing <joel@sing.id.au>
Run-TryBot: Wayne Zuo <wdvxdr@golangcn.org>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Keith Randall <khr@google.com>
Auto-Submit: Keith Randall <khr@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>

3 files changed, 992 insertions, 65 deletions

diff --git a/src/cmd/compile/internal/ssa/gen/RISCV64.rules b/src/cmd/compile/internal/ssa/gen/RISCV64.rules
index 11506e837e..82a9c83284 100644
--- a/src/cmd/compile/internal/ssa/gen/RISCV64.rules
+++ b/src/cmd/compile/internal/ssa/gen/RISCV64.rules
@@ -172,41 +172,51 @@
 // If y < 64, this is the value we want. Otherwise, we want zero.
 //
 // So, we AND with -1 * uint64(y < 64), which is 0xfffff... if y < 64 and 0 otherwise.
-(Lsh8x8   <t> x y) => (AND (SLL <t> x y) (Neg8  <t> (SLTIU <t> [64] (ZeroExt8to64  y))))
-(Lsh8x16  <t> x y) => (AND (SLL <t> x y) (Neg8  <t> (SLTIU <t> [64] (ZeroExt16to64 y))))
-(Lsh8x32  <t> x y) => (AND (SLL <t> x y) (Neg8  <t> (SLTIU <t> [64] (ZeroExt32to64 y))))
-(Lsh8x64  <t> x y) => (AND (SLL <t> x y) (Neg8  <t> (SLTIU <t> [64] y)))
-(Lsh16x8  <t> x y) => (AND (SLL <t> x y) (Neg16 <t> (SLTIU <t> [64] (ZeroExt8to64  y))))
-(Lsh16x16 <t> x y) => (AND (SLL <t> x y) (Neg16 <t> (SLTIU <t> [64] (ZeroExt16to64 y))))
-(Lsh16x32 <t> x y) => (AND (SLL <t> x y) (Neg16 <t> (SLTIU <t> [64] (ZeroExt32to64 y))))
-(Lsh16x64 <t> x y) => (AND (SLL <t> x y) (Neg16 <t> (SLTIU <t> [64] y)))
-(Lsh32x8  <t> x y) => (AND (SLL <t> x y) (Neg32 <t> (SLTIU <t> [64] (ZeroExt8to64  y))))
-(Lsh32x16 <t> x y) => (AND (SLL <t> x y) (Neg32 <t> (SLTIU <t> [64] (ZeroExt16to64 y))))
-(Lsh32x32 <t> x y) => (AND (SLL <t> x y) (Neg32 <t> (SLTIU <t> [64] (ZeroExt32to64 y))))
-(Lsh32x64 <t> x y) => (AND (SLL <t> x y) (Neg32 <t> (SLTIU <t> [64] y)))
-(Lsh64x8  <t> x y) => (AND (SLL <t> x y) (Neg64 <t> (SLTIU <t> [64] (ZeroExt8to64  y))))
-(Lsh64x16 <t> x y) => (AND (SLL <t> x y) (Neg64 <t> (SLTIU <t> [64] (ZeroExt16to64 y))))
-(Lsh64x32 <t> x y) => (AND (SLL <t> x y) (Neg64 <t> (SLTIU <t> [64] (ZeroExt32to64 y))))
-(Lsh64x64 <t> x y) => (AND (SLL <t> x y) (Neg64 <t> (SLTIU <t> [64] y)))
+(Lsh8x8   <t> x y) && !shiftIsBounded(v) => (AND (SLL <t> x y) (Neg8  <t> (SLTIU <t> [64] (ZeroExt8to64  y))))
+(Lsh8x16  <t> x y) && !shiftIsBounded(v) => (AND (SLL <t> x y) (Neg8  <t> (SLTIU <t> [64] (ZeroExt16to64 y))))
+(Lsh8x32  <t> x y) && !shiftIsBounded(v) => (AND (SLL <t> x y) (Neg8  <t> (SLTIU <t> [64] (ZeroExt32to64 y))))
+(Lsh8x64  <t> x y) && !shiftIsBounded(v) => (AND (SLL <t> x y) (Neg8  <t> (SLTIU <t> [64] y)))
+(Lsh16x8  <t> x y) && !shiftIsBounded(v) => (AND (SLL <t> x y) (Neg16 <t> (SLTIU <t> [64] (ZeroExt8to64  y))))
+(Lsh16x16 <t> x y) && !shiftIsBounded(v) => (AND (SLL <t> x y) (Neg16 <t> (SLTIU <t> [64] (ZeroExt16to64 y))))
+(Lsh16x32 <t> x y) && !shiftIsBounded(v) => (AND (SLL <t> x y) (Neg16 <t> (SLTIU <t> [64] (ZeroExt32to64 y))))
+(Lsh16x64 <t> x y) && !shiftIsBounded(v) => (AND (SLL <t> x y) (Neg16 <t> (SLTIU <t> [64] y)))
+(Lsh32x8  <t> x y) && !shiftIsBounded(v) => (AND (SLL <t> x y) (Neg32 <t> (SLTIU <t> [64] (ZeroExt8to64  y))))
+(Lsh32x16 <t> x y) && !shiftIsBounded(v) => (AND (SLL <t> x y) (Neg32 <t> (SLTIU <t> [64] (ZeroExt16to64 y))))
+(Lsh32x32 <t> x y) && !shiftIsBounded(v) => (AND (SLL <t> x y) (Neg32 <t> (SLTIU <t> [64] (ZeroExt32to64 y))))
+(Lsh32x64 <t> x y) && !shiftIsBounded(v) => (AND (SLL <t> x y) (Neg32 <t> (SLTIU <t> [64] y)))
+(Lsh64x8  <t> x y) && !shiftIsBounded(v) => (AND (SLL <t> x y) (Neg64 <t> (SLTIU <t> [64] (ZeroExt8to64  y))))
+(Lsh64x16 <t> x y) && !shiftIsBounded(v) => (AND (SLL <t> x y) (Neg64 <t> (SLTIU <t> [64] (ZeroExt16to64 y))))
+(Lsh64x32 <t> x y) && !shiftIsBounded(v) => (AND (SLL <t> x y) (Neg64 <t> (SLTIU <t> [64] (ZeroExt32to64 y))))
+(Lsh64x64 <t> x y) && !shiftIsBounded(v) => (AND (SLL <t> x y) (Neg64 <t> (SLTIU <t> [64] y)))
+
+(Lsh8x(64|32|16|8)  x y) && shiftIsBounded(v) => (SLL x y)
+(Lsh16x(64|32|16|8) x y) && shiftIsBounded(v) => (SLL x y)
+(Lsh32x(64|32|16|8) x y) && shiftIsBounded(v) => (SLL x y)
+(Lsh64x(64|32|16|8) x y) && shiftIsBounded(v) => (SLL x y)
 
 // SRL only considers the bottom 6 bits of y. If y > 64, the result should
 // always be 0. See Lsh above for a detailed description.
-(Rsh8Ux8   <t> x y) => (AND (SRL <t> (ZeroExt8to64  x) y) (Neg8  <t> (SLTIU <t> [64] (ZeroExt8to64  y))))
-(Rsh8Ux16  <t> x y) => (AND (SRL <t> (ZeroExt8to64  x) y) (Neg8  <t> (SLTIU <t> [64] (ZeroExt16to64 y))))
-(Rsh8Ux32  <t> x y) => (AND (SRL <t> (ZeroExt8to64  x) y) (Neg8  <t> (SLTIU <t> [64] (ZeroExt32to64 y))))
-(Rsh8Ux64  <t> x y) => (AND (SRL <t> (ZeroExt8to64  x) y) (Neg8  <t> (SLTIU <t> [64] y)))
-(Rsh16Ux8  <t> x y) => (AND (SRL <t> (ZeroExt16to64 x) y) (Neg16 <t> (SLTIU <t> [64] (ZeroExt8to64  y))))
-(Rsh16Ux16 <t> x y) => (AND (SRL <t> (ZeroExt16to64 x) y) (Neg16 <t> (SLTIU <t> [64] (ZeroExt16to64 y))))
-(Rsh16Ux32 <t> x y) => (AND (SRL <t> (ZeroExt16to64 x) y) (Neg16 <t> (SLTIU <t> [64] (ZeroExt32to64 y))))
-(Rsh16Ux64 <t> x y) => (AND (SRL <t> (ZeroExt16to64 x) y) (Neg16 <t> (SLTIU <t> [64] y)))
-(Rsh32Ux8  <t> x y) => (AND (SRL <t> (ZeroExt32to64 x) y) (Neg32 <t> (SLTIU <t> [64] (ZeroExt8to64  y))))
-(Rsh32Ux16 <t> x y) => (AND (SRL <t> (ZeroExt32to64 x) y) (Neg32 <t> (SLTIU <t> [64] (ZeroExt16to64 y))))
-(Rsh32Ux32 <t> x y) => (AND (SRL <t> (ZeroExt32to64 x) y) (Neg32 <t> (SLTIU <t> [64] (ZeroExt32to64 y))))
-(Rsh32Ux64 <t> x y) => (AND (SRL <t> (ZeroExt32to64 x) y) (Neg32 <t> (SLTIU <t> [64] y)))
-(Rsh64Ux8  <t> x y) => (AND (SRL <t> x                 y) (Neg64 <t> (SLTIU <t> [64] (ZeroExt8to64  y))))
-(Rsh64Ux16 <t> x y) => (AND (SRL <t> x                 y) (Neg64 <t> (SLTIU <t> [64] (ZeroExt16to64 y))))
-(Rsh64Ux32 <t> x y) => (AND (SRL <t> x                 y) (Neg64 <t> (SLTIU <t> [64] (ZeroExt32to64 y))))
-(Rsh64Ux64 <t> x y) => (AND (SRL <t> x                 y) (Neg64 <t> (SLTIU <t> [64] y)))
+(Rsh8Ux8   <t> x y) && !shiftIsBounded(v) => (AND (SRL <t> (ZeroExt8to64  x) y) (Neg8  <t> (SLTIU <t> [64] (ZeroExt8to64  y))))
+(Rsh8Ux16  <t> x y) && !shiftIsBounded(v) => (AND (SRL <t> (ZeroExt8to64  x) y) (Neg8  <t> (SLTIU <t> [64] (ZeroExt16to64 y))))
+(Rsh8Ux32  <t> x y) && !shiftIsBounded(v) => (AND (SRL <t> (ZeroExt8to64  x) y) (Neg8  <t> (SLTIU <t> [64] (ZeroExt32to64 y))))
+(Rsh8Ux64  <t> x y) && !shiftIsBounded(v) => (AND (SRL <t> (ZeroExt8to64  x) y) (Neg8  <t> (SLTIU <t> [64] y)))
+(Rsh16Ux8  <t> x y) && !shiftIsBounded(v) => (AND (SRL <t> (ZeroExt16to64 x) y) (Neg16 <t> (SLTIU <t> [64] (ZeroExt8to64  y))))
+(Rsh16Ux16 <t> x y) && !shiftIsBounded(v) => (AND (SRL <t> (ZeroExt16to64 x) y) (Neg16 <t> (SLTIU <t> [64] (ZeroExt16to64 y))))
+(Rsh16Ux32 <t> x y) && !shiftIsBounded(v) => (AND (SRL <t> (ZeroExt16to64 x) y) (Neg16 <t> (SLTIU <t> [64] (ZeroExt32to64 y))))
+(Rsh16Ux64 <t> x y) && !shiftIsBounded(v) => (AND (SRL <t> (ZeroExt16to64 x) y) (Neg16 <t> (SLTIU <t> [64] y)))
+(Rsh32Ux8  <t> x y) && !shiftIsBounded(v) => (AND (SRL <t> (ZeroExt32to64 x) y) (Neg32 <t> (SLTIU <t> [64] (ZeroExt8to64  y))))
+(Rsh32Ux16 <t> x y) && !shiftIsBounded(v) => (AND (SRL <t> (ZeroExt32to64 x) y) (Neg32 <t> (SLTIU <t> [64] (ZeroExt16to64 y))))
+(Rsh32Ux32 <t> x y) && !shiftIsBounded(v) => (AND (SRL <t> (ZeroExt32to64 x) y) (Neg32 <t> (SLTIU <t> [64] (ZeroExt32to64 y))))
+(Rsh32Ux64 <t> x y) && !shiftIsBounded(v) => (AND (SRL <t> (ZeroExt32to64 x) y) (Neg32 <t> (SLTIU <t> [64] y)))
+(Rsh64Ux8  <t> x y) && !shiftIsBounded(v) => (AND (SRL <t> x                 y) (Neg64 <t> (SLTIU <t> [64] (ZeroExt8to64  y))))
+(Rsh64Ux16 <t> x y) && !shiftIsBounded(v) => (AND (SRL <t> x                 y) (Neg64 <t> (SLTIU <t> [64] (ZeroExt16to64 y))))
+(Rsh64Ux32 <t> x y) && !shiftIsBounded(v) => (AND (SRL <t> x                 y) (Neg64 <t> (SLTIU <t> [64] (ZeroExt32to64 y))))
+(Rsh64Ux64 <t> x y) && !shiftIsBounded(v) => (AND (SRL <t> x                 y) (Neg64 <t> (SLTIU <t> [64] y)))
+
+(Rsh8Ux(64|32|16|8)  x y) && shiftIsBounded(v) => (SRL (ZeroExt8to64  x) y)
+(Rsh16Ux(64|32|16|8) x y) && shiftIsBounded(v) => (SRL (ZeroExt16to64 x) y)
+(Rsh32Ux(64|32|16|8) x y) && shiftIsBounded(v) => (SRL (ZeroExt32to64 x) y)
+(Rsh64Ux(64|32|16|8) x y) && shiftIsBounded(v) => (SRL x                 y)
 
 // SRA only considers the bottom 6 bits of y. If y > 64, the result should
 // be either 0 or -1 based on the sign bit.
@@ -218,22 +228,27 @@
 //
 // We don't need to sign-extend the OR result, as it will be at minimum 8 bits,
 // more than the 6 bits SRA cares about.
-(Rsh8x8   <t> x y) => (SRA <t> (SignExt8to64  x) (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] (ZeroExt8to64  y)))))
-(Rsh8x16  <t> x y) => (SRA <t> (SignExt8to64  x) (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] (ZeroExt16to64 y)))))
-(Rsh8x32  <t> x y) => (SRA <t> (SignExt8to64  x) (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] (ZeroExt32to64 y)))))
-(Rsh8x64  <t> x y) => (SRA <t> (SignExt8to64  x) (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] y))))
-(Rsh16x8  <t> x y) => (SRA <t> (SignExt16to64 x) (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] (ZeroExt8to64  y)))))
-(Rsh16x16 <t> x y) => (SRA <t> (SignExt16to64 x) (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] (ZeroExt16to64 y)))))
-(Rsh16x32 <t> x y) => (SRA <t> (SignExt16to64 x) (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] (ZeroExt32to64 y)))))
-(Rsh16x64 <t> x y) => (SRA <t> (SignExt16to64 x) (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] y))))
-(Rsh32x8  <t> x y) => (SRA <t> (SignExt32to64 x) (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] (ZeroExt8to64  y)))))
-(Rsh32x16 <t> x y) => (SRA <t> (SignExt32to64 x) (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] (ZeroExt16to64 y)))))
-(Rsh32x32 <t> x y) => (SRA <t> (SignExt32to64 x) (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] (ZeroExt32to64 y)))))
-(Rsh32x64 <t> x y) => (SRA <t> (SignExt32to64 x) (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] y))))
-(Rsh64x8  <t> x y) => (SRA <t> x                 (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] (ZeroExt8to64  y)))))
-(Rsh64x16 <t> x y) => (SRA <t> x                 (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] (ZeroExt16to64 y)))))
-(Rsh64x32 <t> x y) => (SRA <t> x                 (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] (ZeroExt32to64 y)))))
-(Rsh64x64 <t> x y) => (SRA <t> x                 (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] y))))
+(Rsh8x8   <t> x y) && !shiftIsBounded(v) => (SRA <t> (SignExt8to64  x) (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] (ZeroExt8to64  y)))))
+(Rsh8x16  <t> x y) && !shiftIsBounded(v) => (SRA <t> (SignExt8to64  x) (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] (ZeroExt16to64 y)))))
+(Rsh8x32  <t> x y) && !shiftIsBounded(v) => (SRA <t> (SignExt8to64  x) (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] (ZeroExt32to64 y)))))
+(Rsh8x64  <t> x y) && !shiftIsBounded(v) => (SRA <t> (SignExt8to64  x) (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] y))))
+(Rsh16x8  <t> x y) && !shiftIsBounded(v) => (SRA <t> (SignExt16to64 x) (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] (ZeroExt8to64  y)))))
+(Rsh16x16 <t> x y) && !shiftIsBounded(v) => (SRA <t> (SignExt16to64 x) (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] (ZeroExt16to64 y)))))
+(Rsh16x32 <t> x y) && !shiftIsBounded(v) => (SRA <t> (SignExt16to64 x) (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] (ZeroExt32to64 y)))))
+(Rsh16x64 <t> x y) && !shiftIsBounded(v) => (SRA <t> (SignExt16to64 x) (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] y))))
+(Rsh32x8  <t> x y) && !shiftIsBounded(v) => (SRA <t> (SignExt32to64 x) (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] (ZeroExt8to64  y)))))
+(Rsh32x16 <t> x y) && !shiftIsBounded(v) => (SRA <t> (SignExt32to64 x) (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] (ZeroExt16to64 y)))))
+(Rsh32x32 <t> x y) && !shiftIsBounded(v) => (SRA <t> (SignExt32to64 x) (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] (ZeroExt32to64 y)))))
+(Rsh32x64 <t> x y) && !shiftIsBounded(v) => (SRA <t> (SignExt32to64 x) (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] y))))
+(Rsh64x8  <t> x y) && !shiftIsBounded(v) => (SRA <t> x                 (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] (ZeroExt8to64  y)))))
+(Rsh64x16 <t> x y) && !shiftIsBounded(v) => (SRA <t> x                 (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] (ZeroExt16to64 y)))))
+(Rsh64x32 <t> x y) && !shiftIsBounded(v) => (SRA <t> x                 (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] (ZeroExt32to64 y)))))
+(Rsh64x64 <t> x y) && !shiftIsBounded(v) => (SRA <t> x                 (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] y))))
+
+(Rsh8x(64|32|16|8)  x y) && shiftIsBounded(v) => (SRA (SignExt8to64  x) y)
+(Rsh16x(64|32|16|8) x y) && shiftIsBounded(v) => (SRA (SignExt16to64 x) y)
+(Rsh32x(64|32|16|8) x y) && shiftIsBounded(v) => (SRA (SignExt32to64 x) y)
+(Rsh64x(64|32|16|8) x y) && shiftIsBounded(v) => (SRA x                 y)
 
 // Rotates.
 (RotateLeft8  <t> x (MOVDconst [c])) => (Or8  (Lsh8x64  <t> x (MOVDconst [c&7]))  (Rsh8Ux64  <t> x (MOVDconst [-c&7])))
diff --git a/src/cmd/compile/internal/ssa/rewriteRISCV64.go b/src/cmd/compile/internal/ssa/rewriteRISCV64.go
index 70eca6c513..a46664fc90 100644
--- a/src/cmd/compile/internal/ssa/rewriteRISCV64.go
+++ b/src/cmd/compile/internal/ssa/rewriteRISCV64.go
@@ -1607,11 +1607,15 @@ func rewriteValueRISCV64_OpLsh16x16(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Lsh16x16 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (AND (SLL <t> x y) (Neg16 <t> (SLTIU <t> [64] (ZeroExt16to64 y))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64AND)
 		v0 := b.NewValue0(v.Pos, OpRISCV64SLL, t)
 		v0.AddArg2(x, y)
@@ -1625,6 +1629,20 @@ func rewriteValueRISCV64_OpLsh16x16(v *Value) bool {
 		v.AddArg2(v0, v1)
 		return true
 	}
+	// match: (Lsh16x16 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SLL x y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SLL)
+		v.AddArg2(x, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpLsh16x32(v *Value) bool {
 	v_1 := v.Args[1]
@@ -1632,11 +1650,15 @@ func rewriteValueRISCV64_OpLsh16x32(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Lsh16x32 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (AND (SLL <t> x y) (Neg16 <t> (SLTIU <t> [64] (ZeroExt32to64 y))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64AND)
 		v0 := b.NewValue0(v.Pos, OpRISCV64SLL, t)
 		v0.AddArg2(x, y)
@@ -1650,17 +1672,35 @@ func rewriteValueRISCV64_OpLsh16x32(v *Value) bool {
 		v.AddArg2(v0, v1)
 		return true
 	}
+	// match: (Lsh16x32 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SLL x y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SLL)
+		v.AddArg2(x, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpLsh16x64(v *Value) bool {
 	v_1 := v.Args[1]
 	v_0 := v.Args[0]
 	b := v.Block
 	// match: (Lsh16x64 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (AND (SLL <t> x y) (Neg16 <t> (SLTIU <t> [64] y)))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64AND)
 		v0 := b.NewValue0(v.Pos, OpRISCV64SLL, t)
 		v0.AddArg2(x, y)
@@ -1672,6 +1712,20 @@ func rewriteValueRISCV64_OpLsh16x64(v *Value) bool {
 		v.AddArg2(v0, v1)
 		return true
 	}
+	// match: (Lsh16x64 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SLL x y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SLL)
+		v.AddArg2(x, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpLsh16x8(v *Value) bool {
 	v_1 := v.Args[1]
@@ -1679,11 +1733,15 @@ func rewriteValueRISCV64_OpLsh16x8(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Lsh16x8 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (AND (SLL <t> x y) (Neg16 <t> (SLTIU <t> [64] (ZeroExt8to64 y))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64AND)
 		v0 := b.NewValue0(v.Pos, OpRISCV64SLL, t)
 		v0.AddArg2(x, y)
@@ -1697,6 +1755,20 @@ func rewriteValueRISCV64_OpLsh16x8(v *Value) bool {
 		v.AddArg2(v0, v1)
 		return true
 	}
+	// match: (Lsh16x8 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SLL x y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SLL)
+		v.AddArg2(x, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpLsh32x16(v *Value) bool {
 	v_1 := v.Args[1]
@@ -1704,11 +1776,15 @@ func rewriteValueRISCV64_OpLsh32x16(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Lsh32x16 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (AND (SLL <t> x y) (Neg32 <t> (SLTIU <t> [64] (ZeroExt16to64 y))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64AND)
 		v0 := b.NewValue0(v.Pos, OpRISCV64SLL, t)
 		v0.AddArg2(x, y)
@@ -1722,6 +1798,20 @@ func rewriteValueRISCV64_OpLsh32x16(v *Value) bool {
 		v.AddArg2(v0, v1)
 		return true
 	}
+	// match: (Lsh32x16 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SLL x y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SLL)
+		v.AddArg2(x, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpLsh32x32(v *Value) bool {
 	v_1 := v.Args[1]
@@ -1729,11 +1819,15 @@ func rewriteValueRISCV64_OpLsh32x32(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Lsh32x32 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (AND (SLL <t> x y) (Neg32 <t> (SLTIU <t> [64] (ZeroExt32to64 y))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64AND)
 		v0 := b.NewValue0(v.Pos, OpRISCV64SLL, t)
 		v0.AddArg2(x, y)
@@ -1747,17 +1841,35 @@ func rewriteValueRISCV64_OpLsh32x32(v *Value) bool {
 		v.AddArg2(v0, v1)
 		return true
 	}
+	// match: (Lsh32x32 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SLL x y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SLL)
+		v.AddArg2(x, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpLsh32x64(v *Value) bool {
 	v_1 := v.Args[1]
 	v_0 := v.Args[0]
 	b := v.Block
 	// match: (Lsh32x64 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (AND (SLL <t> x y) (Neg32 <t> (SLTIU <t> [64] y)))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64AND)
 		v0 := b.NewValue0(v.Pos, OpRISCV64SLL, t)
 		v0.AddArg2(x, y)
@@ -1769,6 +1881,20 @@ func rewriteValueRISCV64_OpLsh32x64(v *Value) bool {
 		v.AddArg2(v0, v1)
 		return true
 	}
+	// match: (Lsh32x64 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SLL x y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SLL)
+		v.AddArg2(x, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpLsh32x8(v *Value) bool {
 	v_1 := v.Args[1]
@@ -1776,11 +1902,15 @@ func rewriteValueRISCV64_OpLsh32x8(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Lsh32x8 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (AND (SLL <t> x y) (Neg32 <t> (SLTIU <t> [64] (ZeroExt8to64 y))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64AND)
 		v0 := b.NewValue0(v.Pos, OpRISCV64SLL, t)
 		v0.AddArg2(x, y)
@@ -1794,6 +1924,20 @@ func rewriteValueRISCV64_OpLsh32x8(v *Value) bool {
 		v.AddArg2(v0, v1)
 		return true
 	}
+	// match: (Lsh32x8 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SLL x y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SLL)
+		v.AddArg2(x, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpLsh64x16(v *Value) bool {
 	v_1 := v.Args[1]
@@ -1801,11 +1945,15 @@ func rewriteValueRISCV64_OpLsh64x16(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Lsh64x16 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (AND (SLL <t> x y) (Neg64 <t> (SLTIU <t> [64] (ZeroExt16to64 y))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64AND)
 		v0 := b.NewValue0(v.Pos, OpRISCV64SLL, t)
 		v0.AddArg2(x, y)
@@ -1819,6 +1967,20 @@ func rewriteValueRISCV64_OpLsh64x16(v *Value) bool {
 		v.AddArg2(v0, v1)
 		return true
 	}
+	// match: (Lsh64x16 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SLL x y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SLL)
+		v.AddArg2(x, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpLsh64x32(v *Value) bool {
 	v_1 := v.Args[1]
@@ -1826,11 +1988,15 @@ func rewriteValueRISCV64_OpLsh64x32(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Lsh64x32 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (AND (SLL <t> x y) (Neg64 <t> (SLTIU <t> [64] (ZeroExt32to64 y))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64AND)
 		v0 := b.NewValue0(v.Pos, OpRISCV64SLL, t)
 		v0.AddArg2(x, y)
@@ -1844,17 +2010,35 @@ func rewriteValueRISCV64_OpLsh64x32(v *Value) bool {
 		v.AddArg2(v0, v1)
 		return true
 	}
+	// match: (Lsh64x32 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SLL x y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SLL)
+		v.AddArg2(x, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpLsh64x64(v *Value) bool {
 	v_1 := v.Args[1]
 	v_0 := v.Args[0]
 	b := v.Block
 	// match: (Lsh64x64 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (AND (SLL <t> x y) (Neg64 <t> (SLTIU <t> [64] y)))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64AND)
 		v0 := b.NewValue0(v.Pos, OpRISCV64SLL, t)
 		v0.AddArg2(x, y)
@@ -1866,6 +2050,20 @@ func rewriteValueRISCV64_OpLsh64x64(v *Value) bool {
 		v.AddArg2(v0, v1)
 		return true
 	}
+	// match: (Lsh64x64 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SLL x y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SLL)
+		v.AddArg2(x, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpLsh64x8(v *Value) bool {
 	v_1 := v.Args[1]
@@ -1873,11 +2071,15 @@ func rewriteValueRISCV64_OpLsh64x8(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Lsh64x8 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (AND (SLL <t> x y) (Neg64 <t> (SLTIU <t> [64] (ZeroExt8to64 y))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64AND)
 		v0 := b.NewValue0(v.Pos, OpRISCV64SLL, t)
 		v0.AddArg2(x, y)
@@ -1891,6 +2093,20 @@ func rewriteValueRISCV64_OpLsh64x8(v *Value) bool {
 		v.AddArg2(v0, v1)
 		return true
 	}
+	// match: (Lsh64x8 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SLL x y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SLL)
+		v.AddArg2(x, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpLsh8x16(v *Value) bool {
 	v_1 := v.Args[1]
@@ -1898,11 +2114,15 @@ func rewriteValueRISCV64_OpLsh8x16(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Lsh8x16 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (AND (SLL <t> x y) (Neg8 <t> (SLTIU <t> [64] (ZeroExt16to64 y))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64AND)
 		v0 := b.NewValue0(v.Pos, OpRISCV64SLL, t)
 		v0.AddArg2(x, y)
@@ -1916,6 +2136,20 @@ func rewriteValueRISCV64_OpLsh8x16(v *Value) bool {
 		v.AddArg2(v0, v1)
 		return true
 	}
+	// match: (Lsh8x16 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SLL x y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SLL)
+		v.AddArg2(x, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpLsh8x32(v *Value) bool {
 	v_1 := v.Args[1]
@@ -1923,11 +2157,15 @@ func rewriteValueRISCV64_OpLsh8x32(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Lsh8x32 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (AND (SLL <t> x y) (Neg8 <t> (SLTIU <t> [64] (ZeroExt32to64 y))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64AND)
 		v0 := b.NewValue0(v.Pos, OpRISCV64SLL, t)
 		v0.AddArg2(x, y)
@@ -1941,17 +2179,35 @@ func rewriteValueRISCV64_OpLsh8x32(v *Value) bool {
 		v.AddArg2(v0, v1)
 		return true
 	}
+	// match: (Lsh8x32 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SLL x y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SLL)
+		v.AddArg2(x, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpLsh8x64(v *Value) bool {
 	v_1 := v.Args[1]
 	v_0 := v.Args[0]
 	b := v.Block
 	// match: (Lsh8x64 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (AND (SLL <t> x y) (Neg8 <t> (SLTIU <t> [64] y)))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64AND)
 		v0 := b.NewValue0(v.Pos, OpRISCV64SLL, t)
 		v0.AddArg2(x, y)
@@ -1963,6 +2219,20 @@ func rewriteValueRISCV64_OpLsh8x64(v *Value) bool {
 		v.AddArg2(v0, v1)
 		return true
 	}
+	// match: (Lsh8x64 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SLL x y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SLL)
+		v.AddArg2(x, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpLsh8x8(v *Value) bool {
 	v_1 := v.Args[1]
@@ -1970,11 +2240,15 @@ func rewriteValueRISCV64_OpLsh8x8(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Lsh8x8 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (AND (SLL <t> x y) (Neg8 <t> (SLTIU <t> [64] (ZeroExt8to64 y))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64AND)
 		v0 := b.NewValue0(v.Pos, OpRISCV64SLL, t)
 		v0.AddArg2(x, y)
@@ -1988,6 +2262,20 @@ func rewriteValueRISCV64_OpLsh8x8(v *Value) bool {
 		v.AddArg2(v0, v1)
 		return true
 	}
+	// match: (Lsh8x8 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SLL x y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SLL)
+		v.AddArg2(x, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpMod16(v *Value) bool {
 	v_1 := v.Args[1]
@@ -5418,11 +5706,15 @@ func rewriteValueRISCV64_OpRsh16Ux16(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Rsh16Ux16 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (AND (SRL <t> (ZeroExt16to64 x) y) (Neg16 <t> (SLTIU <t> [64] (ZeroExt16to64 y))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64AND)
 		v0 := b.NewValue0(v.Pos, OpRISCV64SRL, t)
 		v1 := b.NewValue0(v.Pos, OpZeroExt16to64, typ.UInt64)
@@ -5438,6 +5730,22 @@ func rewriteValueRISCV64_OpRsh16Ux16(v *Value) bool {
 		v.AddArg2(v0, v2)
 		return true
 	}
+	// match: (Rsh16Ux16 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SRL (ZeroExt16to64 x) y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SRL)
+		v0 := b.NewValue0(v.Pos, OpZeroExt16to64, typ.UInt64)
+		v0.AddArg(x)
+		v.AddArg2(v0, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpRsh16Ux32(v *Value) bool {
 	v_1 := v.Args[1]
@@ -5445,11 +5753,15 @@ func rewriteValueRISCV64_OpRsh16Ux32(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Rsh16Ux32 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (AND (SRL <t> (ZeroExt16to64 x) y) (Neg16 <t> (SLTIU <t> [64] (ZeroExt32to64 y))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64AND)
 		v0 := b.NewValue0(v.Pos, OpRISCV64SRL, t)
 		v1 := b.NewValue0(v.Pos, OpZeroExt16to64, typ.UInt64)
@@ -5465,6 +5777,22 @@ func rewriteValueRISCV64_OpRsh16Ux32(v *Value) bool {
 		v.AddArg2(v0, v2)
 		return true
 	}
+	// match: (Rsh16Ux32 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SRL (ZeroExt16to64 x) y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SRL)
+		v0 := b.NewValue0(v.Pos, OpZeroExt16to64, typ.UInt64)
+		v0.AddArg(x)
+		v.AddArg2(v0, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpRsh16Ux64(v *Value) bool {
 	v_1 := v.Args[1]
@@ -5472,11 +5800,15 @@ func rewriteValueRISCV64_OpRsh16Ux64(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Rsh16Ux64 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (AND (SRL <t> (ZeroExt16to64 x) y) (Neg16 <t> (SLTIU <t> [64] y)))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64AND)
 		v0 := b.NewValue0(v.Pos, OpRISCV64SRL, t)
 		v1 := b.NewValue0(v.Pos, OpZeroExt16to64, typ.UInt64)
@@ -5490,6 +5822,22 @@ func rewriteValueRISCV64_OpRsh16Ux64(v *Value) bool {
 		v.AddArg2(v0, v2)
 		return true
 	}
+	// match: (Rsh16Ux64 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SRL (ZeroExt16to64 x) y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SRL)
+		v0 := b.NewValue0(v.Pos, OpZeroExt16to64, typ.UInt64)
+		v0.AddArg(x)
+		v.AddArg2(v0, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpRsh16Ux8(v *Value) bool {
 	v_1 := v.Args[1]
@@ -5497,11 +5845,15 @@ func rewriteValueRISCV64_OpRsh16Ux8(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Rsh16Ux8 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (AND (SRL <t> (ZeroExt16to64 x) y) (Neg16 <t> (SLTIU <t> [64] (ZeroExt8to64 y))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64AND)
 		v0 := b.NewValue0(v.Pos, OpRISCV64SRL, t)
 		v1 := b.NewValue0(v.Pos, OpZeroExt16to64, typ.UInt64)
@@ -5517,6 +5869,22 @@ func rewriteValueRISCV64_OpRsh16Ux8(v *Value) bool {
 		v.AddArg2(v0, v2)
 		return true
 	}
+	// match: (Rsh16Ux8 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SRL (ZeroExt16to64 x) y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SRL)
+		v0 := b.NewValue0(v.Pos, OpZeroExt16to64, typ.UInt64)
+		v0.AddArg(x)
+		v.AddArg2(v0, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpRsh16x16(v *Value) bool {
 	v_1 := v.Args[1]
@@ -5524,11 +5892,15 @@ func rewriteValueRISCV64_OpRsh16x16(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Rsh16x16 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (SRA <t> (SignExt16to64 x) (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] (ZeroExt16to64 y)))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64SRA)
 		v.Type = t
 		v0 := b.NewValue0(v.Pos, OpSignExt16to64, typ.Int64)
@@ -5546,6 +5918,22 @@ func rewriteValueRISCV64_OpRsh16x16(v *Value) bool {
 		v.AddArg2(v0, v1)
 		return true
 	}
+	// match: (Rsh16x16 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SRA (SignExt16to64 x) y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SRA)
+		v0 := b.NewValue0(v.Pos, OpSignExt16to64, typ.Int64)
+		v0.AddArg(x)
+		v.AddArg2(v0, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpRsh16x32(v *Value) bool {
 	v_1 := v.Args[1]
@@ -5553,11 +5941,15 @@ func rewriteValueRISCV64_OpRsh16x32(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Rsh16x32 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (SRA <t> (SignExt16to64 x) (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] (ZeroExt32to64 y)))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64SRA)
 		v.Type = t
 		v0 := b.NewValue0(v.Pos, OpSignExt16to64, typ.Int64)
@@ -5575,6 +5967,22 @@ func rewriteValueRISCV64_OpRsh16x32(v *Value) bool {
 		v.AddArg2(v0, v1)
 		return true
 	}
+	// match: (Rsh16x32 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SRA (SignExt16to64 x) y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SRA)
+		v0 := b.NewValue0(v.Pos, OpSignExt16to64, typ.Int64)
+		v0.AddArg(x)
+		v.AddArg2(v0, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpRsh16x64(v *Value) bool {
 	v_1 := v.Args[1]
@@ -5582,11 +5990,15 @@ func rewriteValueRISCV64_OpRsh16x64(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Rsh16x64 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (SRA <t> (SignExt16to64 x) (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] y))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64SRA)
 		v.Type = t
 		v0 := b.NewValue0(v.Pos, OpSignExt16to64, typ.Int64)
@@ -5602,6 +6014,22 @@ func rewriteValueRISCV64_OpRsh16x64(v *Value) bool {
 		v.AddArg2(v0, v1)
 		return true
 	}
+	// match: (Rsh16x64 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SRA (SignExt16to64 x) y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SRA)
+		v0 := b.NewValue0(v.Pos, OpSignExt16to64, typ.Int64)
+		v0.AddArg(x)
+		v.AddArg2(v0, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpRsh16x8(v *Value) bool {
 	v_1 := v.Args[1]
@@ -5609,11 +6037,15 @@ func rewriteValueRISCV64_OpRsh16x8(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Rsh16x8 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (SRA <t> (SignExt16to64 x) (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] (ZeroExt8to64 y)))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64SRA)
 		v.Type = t
 		v0 := b.NewValue0(v.Pos, OpSignExt16to64, typ.Int64)
@@ -5631,6 +6063,22 @@ func rewriteValueRISCV64_OpRsh16x8(v *Value) bool {
 		v.AddArg2(v0, v1)
 		return true
 	}
+	// match: (Rsh16x8 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SRA (SignExt16to64 x) y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SRA)
+		v0 := b.NewValue0(v.Pos, OpSignExt16to64, typ.Int64)
+		v0.AddArg(x)
+		v.AddArg2(v0, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpRsh32Ux16(v *Value) bool {
 	v_1 := v.Args[1]
@@ -5638,11 +6086,15 @@ func rewriteValueRISCV64_OpRsh32Ux16(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Rsh32Ux16 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (AND (SRL <t> (ZeroExt32to64 x) y) (Neg32 <t> (SLTIU <t> [64] (ZeroExt16to64 y))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64AND)
 		v0 := b.NewValue0(v.Pos, OpRISCV64SRL, t)
 		v1 := b.NewValue0(v.Pos, OpZeroExt32to64, typ.UInt64)
@@ -5658,6 +6110,22 @@ func rewriteValueRISCV64_OpRsh32Ux16(v *Value) bool {
 		v.AddArg2(v0, v2)
 		return true
 	}
+	// match: (Rsh32Ux16 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SRL (ZeroExt32to64 x) y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SRL)
+		v0 := b.NewValue0(v.Pos, OpZeroExt32to64, typ.UInt64)
+		v0.AddArg(x)
+		v.AddArg2(v0, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpRsh32Ux32(v *Value) bool {
 	v_1 := v.Args[1]
@@ -5665,11 +6133,15 @@ func rewriteValueRISCV64_OpRsh32Ux32(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Rsh32Ux32 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (AND (SRL <t> (ZeroExt32to64 x) y) (Neg32 <t> (SLTIU <t> [64] (ZeroExt32to64 y))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64AND)
 		v0 := b.NewValue0(v.Pos, OpRISCV64SRL, t)
 		v1 := b.NewValue0(v.Pos, OpZeroExt32to64, typ.UInt64)
@@ -5685,6 +6157,22 @@ func rewriteValueRISCV64_OpRsh32Ux32(v *Value) bool {
 		v.AddArg2(v0, v2)
 		return true
 	}
+	// match: (Rsh32Ux32 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SRL (ZeroExt32to64 x) y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SRL)
+		v0 := b.NewValue0(v.Pos, OpZeroExt32to64, typ.UInt64)
+		v0.AddArg(x)
+		v.AddArg2(v0, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpRsh32Ux64(v *Value) bool {
 	v_1 := v.Args[1]
@@ -5692,11 +6180,15 @@ func rewriteValueRISCV64_OpRsh32Ux64(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Rsh32Ux64 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (AND (SRL <t> (ZeroExt32to64 x) y) (Neg32 <t> (SLTIU <t> [64] y)))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64AND)
 		v0 := b.NewValue0(v.Pos, OpRISCV64SRL, t)
 		v1 := b.NewValue0(v.Pos, OpZeroExt32to64, typ.UInt64)
@@ -5710,6 +6202,22 @@ func rewriteValueRISCV64_OpRsh32Ux64(v *Value) bool {
 		v.AddArg2(v0, v2)
 		return true
 	}
+	// match: (Rsh32Ux64 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SRL (ZeroExt32to64 x) y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SRL)
+		v0 := b.NewValue0(v.Pos, OpZeroExt32to64, typ.UInt64)
+		v0.AddArg(x)
+		v.AddArg2(v0, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpRsh32Ux8(v *Value) bool {
 	v_1 := v.Args[1]
@@ -5717,11 +6225,15 @@ func rewriteValueRISCV64_OpRsh32Ux8(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Rsh32Ux8 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (AND (SRL <t> (ZeroExt32to64 x) y) (Neg32 <t> (SLTIU <t> [64] (ZeroExt8to64 y))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64AND)
 		v0 := b.NewValue0(v.Pos, OpRISCV64SRL, t)
 		v1 := b.NewValue0(v.Pos, OpZeroExt32to64, typ.UInt64)
@@ -5737,6 +6249,22 @@ func rewriteValueRISCV64_OpRsh32Ux8(v *Value) bool {
 		v.AddArg2(v0, v2)
 		return true
 	}
+	// match: (Rsh32Ux8 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SRL (ZeroExt32to64 x) y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SRL)
+		v0 := b.NewValue0(v.Pos, OpZeroExt32to64, typ.UInt64)
+		v0.AddArg(x)
+		v.AddArg2(v0, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpRsh32x16(v *Value) bool {
 	v_1 := v.Args[1]
@@ -5744,11 +6272,15 @@ func rewriteValueRISCV64_OpRsh32x16(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Rsh32x16 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (SRA <t> (SignExt32to64 x) (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] (ZeroExt16to64 y)))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64SRA)
 		v.Type = t
 		v0 := b.NewValue0(v.Pos, OpSignExt32to64, typ.Int64)
@@ -5766,6 +6298,22 @@ func rewriteValueRISCV64_OpRsh32x16(v *Value) bool {
 		v.AddArg2(v0, v1)
 		return true
 	}
+	// match: (Rsh32x16 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SRA (SignExt32to64 x) y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SRA)
+		v0 := b.NewValue0(v.Pos, OpSignExt32to64, typ.Int64)
+		v0.AddArg(x)
+		v.AddArg2(v0, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpRsh32x32(v *Value) bool {
 	v_1 := v.Args[1]
@@ -5773,11 +6321,15 @@ func rewriteValueRISCV64_OpRsh32x32(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Rsh32x32 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (SRA <t> (SignExt32to64 x) (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] (ZeroExt32to64 y)))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64SRA)
 		v.Type = t
 		v0 := b.NewValue0(v.Pos, OpSignExt32to64, typ.Int64)
@@ -5795,6 +6347,22 @@ func rewriteValueRISCV64_OpRsh32x32(v *Value) bool {
 		v.AddArg2(v0, v1)
 		return true
 	}
+	// match: (Rsh32x32 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SRA (SignExt32to64 x) y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SRA)
+		v0 := b.NewValue0(v.Pos, OpSignExt32to64, typ.Int64)
+		v0.AddArg(x)
+		v.AddArg2(v0, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpRsh32x64(v *Value) bool {
 	v_1 := v.Args[1]
@@ -5802,11 +6370,15 @@ func rewriteValueRISCV64_OpRsh32x64(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Rsh32x64 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (SRA <t> (SignExt32to64 x) (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] y))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64SRA)
 		v.Type = t
 		v0 := b.NewValue0(v.Pos, OpSignExt32to64, typ.Int64)
@@ -5822,6 +6394,22 @@ func rewriteValueRISCV64_OpRsh32x64(v *Value) bool {
 		v.AddArg2(v0, v1)
 		return true
 	}
+	// match: (Rsh32x64 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SRA (SignExt32to64 x) y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SRA)
+		v0 := b.NewValue0(v.Pos, OpSignExt32to64, typ.Int64)
+		v0.AddArg(x)
+		v.AddArg2(v0, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpRsh32x8(v *Value) bool {
 	v_1 := v.Args[1]
@@ -5829,11 +6417,15 @@ func rewriteValueRISCV64_OpRsh32x8(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Rsh32x8 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (SRA <t> (SignExt32to64 x) (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] (ZeroExt8to64 y)))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64SRA)
 		v.Type = t
 		v0 := b.NewValue0(v.Pos, OpSignExt32to64, typ.Int64)
@@ -5851,6 +6443,22 @@ func rewriteValueRISCV64_OpRsh32x8(v *Value) bool {
 		v.AddArg2(v0, v1)
 		return true
 	}
+	// match: (Rsh32x8 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SRA (SignExt32to64 x) y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SRA)
+		v0 := b.NewValue0(v.Pos, OpSignExt32to64, typ.Int64)
+		v0.AddArg(x)
+		v.AddArg2(v0, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpRsh64Ux16(v *Value) bool {
 	v_1 := v.Args[1]
@@ -5858,11 +6466,15 @@ func rewriteValueRISCV64_OpRsh64Ux16(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Rsh64Ux16 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (AND (SRL <t> x y) (Neg64 <t> (SLTIU <t> [64] (ZeroExt16to64 y))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64AND)
 		v0 := b.NewValue0(v.Pos, OpRISCV64SRL, t)
 		v0.AddArg2(x, y)
@@ -5876,6 +6488,20 @@ func rewriteValueRISCV64_OpRsh64Ux16(v *Value) bool {
 		v.AddArg2(v0, v1)
 		return true
 	}
+	// match: (Rsh64Ux16 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SRL x y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SRL)
+		v.AddArg2(x, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpRsh64Ux32(v *Value) bool {
 	v_1 := v.Args[1]
@@ -5883,11 +6509,15 @@ func rewriteValueRISCV64_OpRsh64Ux32(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Rsh64Ux32 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (AND (SRL <t> x y) (Neg64 <t> (SLTIU <t> [64] (ZeroExt32to64 y))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64AND)
 		v0 := b.NewValue0(v.Pos, OpRISCV64SRL, t)
 		v0.AddArg2(x, y)
@@ -5901,17 +6531,35 @@ func rewriteValueRISCV64_OpRsh64Ux32(v *Value) bool {
 		v.AddArg2(v0, v1)
 		return true
 	}
+	// match: (Rsh64Ux32 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SRL x y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SRL)
+		v.AddArg2(x, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpRsh64Ux64(v *Value) bool {
 	v_1 := v.Args[1]
 	v_0 := v.Args[0]
 	b := v.Block
 	// match: (Rsh64Ux64 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (AND (SRL <t> x y) (Neg64 <t> (SLTIU <t> [64] y)))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64AND)
 		v0 := b.NewValue0(v.Pos, OpRISCV64SRL, t)
 		v0.AddArg2(x, y)
@@ -5923,6 +6571,20 @@ func rewriteValueRISCV64_OpRsh64Ux64(v *Value) bool {
 		v.AddArg2(v0, v1)
 		return true
 	}
+	// match: (Rsh64Ux64 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SRL x y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SRL)
+		v.AddArg2(x, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpRsh64Ux8(v *Value) bool {
 	v_1 := v.Args[1]
@@ -5930,11 +6592,15 @@ func rewriteValueRISCV64_OpRsh64Ux8(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Rsh64Ux8 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (AND (SRL <t> x y) (Neg64 <t> (SLTIU <t> [64] (ZeroExt8to64 y))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64AND)
 		v0 := b.NewValue0(v.Pos, OpRISCV64SRL, t)
 		v0.AddArg2(x, y)
@@ -5948,6 +6614,20 @@ func rewriteValueRISCV64_OpRsh64Ux8(v *Value) bool {
 		v.AddArg2(v0, v1)
 		return true
 	}
+	// match: (Rsh64Ux8 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SRL x y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SRL)
+		v.AddArg2(x, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpRsh64x16(v *Value) bool {
 	v_1 := v.Args[1]
@@ -5955,11 +6635,15 @@ func rewriteValueRISCV64_OpRsh64x16(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Rsh64x16 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (SRA <t> x (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] (ZeroExt16to64 y)))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64SRA)
 		v.Type = t
 		v0 := b.NewValue0(v.Pos, OpRISCV64OR, y.Type)
@@ -5975,6 +6659,20 @@ func rewriteValueRISCV64_OpRsh64x16(v *Value) bool {
 		v.AddArg2(x, v0)
 		return true
 	}
+	// match: (Rsh64x16 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SRA x y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SRA)
+		v.AddArg2(x, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpRsh64x32(v *Value) bool {
 	v_1 := v.Args[1]
@@ -5982,11 +6680,15 @@ func rewriteValueRISCV64_OpRsh64x32(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Rsh64x32 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (SRA <t> x (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] (ZeroExt32to64 y)))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64SRA)
 		v.Type = t
 		v0 := b.NewValue0(v.Pos, OpRISCV64OR, y.Type)
@@ -6002,17 +6704,35 @@ func rewriteValueRISCV64_OpRsh64x32(v *Value) bool {
 		v.AddArg2(x, v0)
 		return true
 	}
+	// match: (Rsh64x32 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SRA x y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SRA)
+		v.AddArg2(x, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpRsh64x64(v *Value) bool {
 	v_1 := v.Args[1]
 	v_0 := v.Args[0]
 	b := v.Block
 	// match: (Rsh64x64 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (SRA <t> x (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] y))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64SRA)
 		v.Type = t
 		v0 := b.NewValue0(v.Pos, OpRISCV64OR, y.Type)
@@ -6026,6 +6746,20 @@ func rewriteValueRISCV64_OpRsh64x64(v *Value) bool {
 		v.AddArg2(x, v0)
 		return true
 	}
+	// match: (Rsh64x64 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SRA x y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SRA)
+		v.AddArg2(x, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpRsh64x8(v *Value) bool {
 	v_1 := v.Args[1]
@@ -6033,11 +6767,15 @@ func rewriteValueRISCV64_OpRsh64x8(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Rsh64x8 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (SRA <t> x (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] (ZeroExt8to64 y)))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64SRA)
 		v.Type = t
 		v0 := b.NewValue0(v.Pos, OpRISCV64OR, y.Type)
@@ -6053,6 +6791,20 @@ func rewriteValueRISCV64_OpRsh64x8(v *Value) bool {
 		v.AddArg2(x, v0)
 		return true
 	}
+	// match: (Rsh64x8 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SRA x y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SRA)
+		v.AddArg2(x, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpRsh8Ux16(v *Value) bool {
 	v_1 := v.Args[1]
@@ -6060,11 +6812,15 @@ func rewriteValueRISCV64_OpRsh8Ux16(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Rsh8Ux16 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (AND (SRL <t> (ZeroExt8to64 x) y) (Neg8 <t> (SLTIU <t> [64] (ZeroExt16to64 y))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64AND)
 		v0 := b.NewValue0(v.Pos, OpRISCV64SRL, t)
 		v1 := b.NewValue0(v.Pos, OpZeroExt8to64, typ.UInt64)
@@ -6080,6 +6836,22 @@ func rewriteValueRISCV64_OpRsh8Ux16(v *Value) bool {
 		v.AddArg2(v0, v2)
 		return true
 	}
+	// match: (Rsh8Ux16 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SRL (ZeroExt8to64 x) y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SRL)
+		v0 := b.NewValue0(v.Pos, OpZeroExt8to64, typ.UInt64)
+		v0.AddArg(x)
+		v.AddArg2(v0, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpRsh8Ux32(v *Value) bool {
 	v_1 := v.Args[1]
@@ -6087,11 +6859,15 @@ func rewriteValueRISCV64_OpRsh8Ux32(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Rsh8Ux32 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (AND (SRL <t> (ZeroExt8to64 x) y) (Neg8 <t> (SLTIU <t> [64] (ZeroExt32to64 y))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64AND)
 		v0 := b.NewValue0(v.Pos, OpRISCV64SRL, t)
 		v1 := b.NewValue0(v.Pos, OpZeroExt8to64, typ.UInt64)
@@ -6107,6 +6883,22 @@ func rewriteValueRISCV64_OpRsh8Ux32(v *Value) bool {
 		v.AddArg2(v0, v2)
 		return true
 	}
+	// match: (Rsh8Ux32 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SRL (ZeroExt8to64 x) y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SRL)
+		v0 := b.NewValue0(v.Pos, OpZeroExt8to64, typ.UInt64)
+		v0.AddArg(x)
+		v.AddArg2(v0, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpRsh8Ux64(v *Value) bool {
 	v_1 := v.Args[1]
@@ -6114,11 +6906,15 @@ func rewriteValueRISCV64_OpRsh8Ux64(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Rsh8Ux64 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (AND (SRL <t> (ZeroExt8to64 x) y) (Neg8 <t> (SLTIU <t> [64] y)))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64AND)
 		v0 := b.NewValue0(v.Pos, OpRISCV64SRL, t)
 		v1 := b.NewValue0(v.Pos, OpZeroExt8to64, typ.UInt64)
@@ -6132,6 +6928,22 @@ func rewriteValueRISCV64_OpRsh8Ux64(v *Value) bool {
 		v.AddArg2(v0, v2)
 		return true
 	}
+	// match: (Rsh8Ux64 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SRL (ZeroExt8to64 x) y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SRL)
+		v0 := b.NewValue0(v.Pos, OpZeroExt8to64, typ.UInt64)
+		v0.AddArg(x)
+		v.AddArg2(v0, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpRsh8Ux8(v *Value) bool {
 	v_1 := v.Args[1]
@@ -6139,11 +6951,15 @@ func rewriteValueRISCV64_OpRsh8Ux8(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Rsh8Ux8 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (AND (SRL <t> (ZeroExt8to64 x) y) (Neg8 <t> (SLTIU <t> [64] (ZeroExt8to64 y))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64AND)
 		v0 := b.NewValue0(v.Pos, OpRISCV64SRL, t)
 		v1 := b.NewValue0(v.Pos, OpZeroExt8to64, typ.UInt64)
@@ -6159,6 +6975,22 @@ func rewriteValueRISCV64_OpRsh8Ux8(v *Value) bool {
 		v.AddArg2(v0, v2)
 		return true
 	}
+	// match: (Rsh8Ux8 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SRL (ZeroExt8to64 x) y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SRL)
+		v0 := b.NewValue0(v.Pos, OpZeroExt8to64, typ.UInt64)
+		v0.AddArg(x)
+		v.AddArg2(v0, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpRsh8x16(v *Value) bool {
 	v_1 := v.Args[1]
@@ -6166,11 +6998,15 @@ func rewriteValueRISCV64_OpRsh8x16(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Rsh8x16 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (SRA <t> (SignExt8to64 x) (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] (ZeroExt16to64 y)))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64SRA)
 		v.Type = t
 		v0 := b.NewValue0(v.Pos, OpSignExt8to64, typ.Int64)
@@ -6188,6 +7024,22 @@ func rewriteValueRISCV64_OpRsh8x16(v *Value) bool {
 		v.AddArg2(v0, v1)
 		return true
 	}
+	// match: (Rsh8x16 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SRA (SignExt8to64 x) y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SRA)
+		v0 := b.NewValue0(v.Pos, OpSignExt8to64, typ.Int64)
+		v0.AddArg(x)
+		v.AddArg2(v0, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpRsh8x32(v *Value) bool {
 	v_1 := v.Args[1]
@@ -6195,11 +7047,15 @@ func rewriteValueRISCV64_OpRsh8x32(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Rsh8x32 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (SRA <t> (SignExt8to64 x) (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] (ZeroExt32to64 y)))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64SRA)
 		v.Type = t
 		v0 := b.NewValue0(v.Pos, OpSignExt8to64, typ.Int64)
@@ -6217,6 +7073,22 @@ func rewriteValueRISCV64_OpRsh8x32(v *Value) bool {
 		v.AddArg2(v0, v1)
 		return true
 	}
+	// match: (Rsh8x32 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SRA (SignExt8to64 x) y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SRA)
+		v0 := b.NewValue0(v.Pos, OpSignExt8to64, typ.Int64)
+		v0.AddArg(x)
+		v.AddArg2(v0, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpRsh8x64(v *Value) bool {
 	v_1 := v.Args[1]
@@ -6224,11 +7096,15 @@ func rewriteValueRISCV64_OpRsh8x64(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Rsh8x64 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (SRA <t> (SignExt8to64 x) (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] y))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64SRA)
 		v.Type = t
 		v0 := b.NewValue0(v.Pos, OpSignExt8to64, typ.Int64)
@@ -6244,6 +7120,22 @@ func rewriteValueRISCV64_OpRsh8x64(v *Value) bool {
 		v.AddArg2(v0, v1)
 		return true
 	}
+	// match: (Rsh8x64 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SRA (SignExt8to64 x) y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SRA)
+		v0 := b.NewValue0(v.Pos, OpSignExt8to64, typ.Int64)
+		v0.AddArg(x)
+		v.AddArg2(v0, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpRsh8x8(v *Value) bool {
 	v_1 := v.Args[1]
@@ -6251,11 +7143,15 @@ func rewriteValueRISCV64_OpRsh8x8(v *Value) bool {
 	b := v.Block
 	typ := &b.Func.Config.Types
 	// match: (Rsh8x8 <t> x y)
+	// cond: !shiftIsBounded(v)
 	// result: (SRA <t> (SignExt8to64 x) (OR <y.Type> y (ADDI <y.Type> [-1] (SLTIU <y.Type> [64] (ZeroExt8to64 y)))))
 	for {
 		t := v.Type
 		x := v_0
 		y := v_1
+		if !(!shiftIsBounded(v)) {
+			break
+		}
 		v.reset(OpRISCV64SRA)
 		v.Type = t
 		v0 := b.NewValue0(v.Pos, OpSignExt8to64, typ.Int64)
@@ -6273,6 +7169,22 @@ func rewriteValueRISCV64_OpRsh8x8(v *Value) bool {
 		v.AddArg2(v0, v1)
 		return true
 	}
+	// match: (Rsh8x8 x y)
+	// cond: shiftIsBounded(v)
+	// result: (SRA (SignExt8to64 x) y)
+	for {
+		x := v_0
+		y := v_1
+		if !(shiftIsBounded(v)) {
+			break
+		}
+		v.reset(OpRISCV64SRA)
+		v0 := b.NewValue0(v.Pos, OpSignExt8to64, typ.Int64)
+		v0.AddArg(x)
+		v.AddArg2(v0, y)
+		return true
+	}
+	return false
 }
 func rewriteValueRISCV64_OpSelect0(v *Value) bool {
 	v_0 := v.Args[0]
diff --git a/test/codegen/shift.go b/test/codegen/shift.go
index 66a5c62391..293924a3db 100644
--- a/test/codegen/shift.go
+++ b/test/codegen/shift.go
@@ -80,7 +80,7 @@ func rshConst64x32(v int64) int64 {
 func lshMask64x64(v int64, s uint64) int64 {
 	// ppc64:"ANDCC",-"ORN",-"ISEL"
 	// ppc64le:"ANDCC",-"ORN",-"ISEL"
-	// riscv64:"SLL","AND","SLTIU"
+	// riscv64:"SLL",-"AND\t",-"SLTIU"
 	// s390x:-"RISBGZ",-"AND",-"LOCGR"
 	return v << (s & 63)
 }
@@ -88,7 +88,7 @@ func lshMask64x64(v int64, s uint64) int64 {
 func rshMask64Ux64(v uint64, s uint64) uint64 {
 	// ppc64:"ANDCC",-"ORN",-"ISEL"
 	// ppc64le:"ANDCC",-"ORN",-"ISEL"
-	// riscv64:"SRL","AND","SLTIU"
+	// riscv64:"SRL",-"AND\t",-"SLTIU"
 	// s390x:-"RISBGZ",-"AND",-"LOCGR"
 	return v >> (s & 63)
 }
@@ -96,7 +96,7 @@ func rshMask64Ux64(v uint64, s uint64) uint64 {
 func rshMask64x64(v int64, s uint64) int64 {
 	// ppc64:"ANDCC",-"ORN",-"ISEL"
 	// ppc64le:"ANDCC",-ORN",-"ISEL"
-	// riscv64:"SRA","OR","SLTIU"
+	// riscv64:"SRA",-"OR",-"SLTIU"
 	// s390x:-"RISBGZ",-"AND",-"LOCGR"
 	return v >> (s & 63)
 }
@@ -128,7 +128,7 @@ func rshMask32x64(v int32, s uint64) int32 {
 func lshMask64x32(v int64, s uint32) int64 {
 	// ppc64:"ANDCC",-"ORN"
 	// ppc64le:"ANDCC",-"ORN"
-	// riscv64:"SLL","AND","SLTIU"
+	// riscv64:"SLL",-"AND\t",-"SLTIU"
 	// s390x:-"RISBGZ",-"AND",-"LOCGR"
 	return v << (s & 63)
 }
@@ -136,7 +136,7 @@ func lshMask64x32(v int64, s uint32) int64 {
 func rshMask64Ux32(v uint64, s uint32) uint64 {
 	// ppc64:"ANDCC",-"ORN"
 	// ppc64le:"ANDCC",-"ORN"
-	// riscv64:"SRL","AND","SLTIU"
+	// riscv64:"SRL",-"AND\t",-"SLTIU"
 	// s390x:-"RISBGZ",-"AND",-"LOCGR"
 	return v >> (s & 63)
 }
@@ -144,7 +144,7 @@ func rshMask64Ux32(v uint64, s uint32) uint64 {
 func rshMask64x32(v int64, s uint32) int64 {
 	// ppc64:"ANDCC",-"ORN",-"ISEL"
 	// ppc64le:"ANDCC",-"ORN",-"ISEL"
-	// riscv64:"SRA","OR","SLTIU"
+	// riscv64:"SRA",-"OR",-"SLTIU"
 	// s390x:-"RISBGZ",-"AND",-"LOCGR"
 	return v >> (s & 63)
 }
@@ -207,7 +207,7 @@ func lshSignedMasked(v8 int8, v16 int16, v32 int32, v64 int64, x int) {
 
 func lshGuarded64(v int64, s uint) int64 {
 	if s < 64 {
-		// riscv64:"SLL","AND","SLTIU"
+		// riscv64:"SLL",-"AND",-"SLTIU"
 		// s390x:-"RISBGZ",-"AND",-"LOCGR"
 		// wasm:-"Select",-".*LtU"
 		return v << s
@@ -217,7 +217,7 @@ func lshGuarded64(v int64, s uint) int64 {
 
 func rshGuarded64U(v uint64, s uint) uint64 {
 	if s < 64 {
-		// riscv64:"SRL","AND","SLTIU"
+		// riscv64:"SRL",-"AND",-"SLTIU"
 		// s390x:-"RISBGZ",-"AND",-"LOCGR"
 		// wasm:-"Select",-".*LtU"
 		return v >> s
@@ -227,7 +227,7 @@ func rshGuarded64U(v uint64, s uint) uint64 {
 
 func rshGuarded64(v int64, s uint) int64 {
 	if s < 64 {
-		// riscv64:"SRA","OR","SLTIU"
+		// riscv64:"SRA",-"OR",-"SLTIU"
 		// s390x:-"RISBGZ",-"AND",-"LOCGR"
 		// wasm:-"Select",-".*LtU"
 		return v >> s
@@ -357,17 +357,17 @@ func checkShiftAndMask32(v []uint32) {
 }
 
 func checkMergedShifts32(a [256]uint32, b [256]uint64, u uint32, v uint32) {
-	//ppc64le: -"CLRLSLDI", "RLWNM\t[$]10, R[0-9]+, [$]22, [$]29, R[0-9]+"
-	//ppc64: -"CLRLSLDI", "RLWNM\t[$]10, R[0-9]+, [$]22, [$]29, R[0-9]+"
+	// ppc64le: -"CLRLSLDI", "RLWNM\t[$]10, R[0-9]+, [$]22, [$]29, R[0-9]+"
+	// ppc64: -"CLRLSLDI", "RLWNM\t[$]10, R[0-9]+, [$]22, [$]29, R[0-9]+"
 	a[0] = a[uint8(v>>24)]
-	//ppc64le: -"CLRLSLDI", "RLWNM\t[$]11, R[0-9]+, [$]21, [$]28, R[0-9]+"
-	//ppc64: -"CLRLSLDI", "RLWNM\t[$]11, R[0-9]+, [$]21, [$]28, R[0-9]+"
+	// ppc64le: -"CLRLSLDI", "RLWNM\t[$]11, R[0-9]+, [$]21, [$]28, R[0-9]+"
+	// ppc64: -"CLRLSLDI", "RLWNM\t[$]11, R[0-9]+, [$]21, [$]28, R[0-9]+"
 	b[0] = b[uint8(v>>24)]
-	//ppc64le: -"CLRLSLDI", "RLWNM\t[$]15, R[0-9]+, [$]21, [$]28, R[0-9]+"
-	//ppc64: -"CLRLSLDI", "RLWNM\t[$]15, R[0-9]+, [$]21, [$]28, R[0-9]+"
+	// ppc64le: -"CLRLSLDI", "RLWNM\t[$]15, R[0-9]+, [$]21, [$]28, R[0-9]+"
+	// ppc64: -"CLRLSLDI", "RLWNM\t[$]15, R[0-9]+, [$]21, [$]28, R[0-9]+"
 	b[1] = b[(v>>20)&0xFF]
-	//ppc64le: -"SLD", "RLWNM\t[$]10, R[0-9]+, [$]22, [$]28, R[0-9]+"
-	//ppc64: -"SLD", "RLWNM\t[$]10, R[0-9]+, [$]22, [$]28, R[0-9]+"
+	// ppc64le: -"SLD", "RLWNM\t[$]10, R[0-9]+, [$]22, [$]28, R[0-9]+"
+	// ppc64: -"SLD", "RLWNM\t[$]10, R[0-9]+, [$]22, [$]28, R[0-9]+"
 	b[2] = b[v>>25]
 }