diff --git a/src/cmd/compile/internal/ssa/gen/RISCV64.rules b/src/cmd/compile/internal/ssa/gen/RISCV64.rules
index e37c7b7899..c2f1c16b6b 100644
--- a/src/cmd/compile/internal/ssa/gen/RISCV64.rules
+++ b/src/cmd/compile/internal/ssa/gen/RISCV64.rules
@@ -801,10 +801,17 @@
 (SLTI  [x] (MOVDconst [y])) => (MOVDconst [b2i(int64(y) < int64(x))])
 (SLTIU [x] (MOVDconst [y])) => (MOVDconst [b2i(uint64(y) < uint64(x))])
 
-(SLT x x)  => (MOVDconst [0])
+// SLTI/SLTIU with known outcomes.
+(SLTI  [x] (ANDI [y] _)) && y >= 0 && int64(y) < int64(x) => (MOVDconst [1])
+(SLTIU [x] (ANDI [y] _)) && y >= 0 && uint64(y) < uint64(x) => (MOVDconst [1])
+(SLTI  [x] (ORI  [y] _)) && y >= 0 && int64(y) >= int64(x) => (MOVDconst [0])
+(SLTIU [x] (ORI  [y] _)) && y >= 0 && uint64(y) >= uint64(x) => (MOVDconst [0])
+
+// SLT/SLTU with known outcomes.
+(SLT  x x) => (MOVDconst [0])
 (SLTU x x) => (MOVDconst [0])
 
-// deadcode for LoweredMuluhilo
+// Deadcode for LoweredMuluhilo
 (Select0 m:(LoweredMuluhilo x y)) && m.Uses == 1 => (MULHU x y)
 (Select1 m:(LoweredMuluhilo x y)) && m.Uses == 1 => (MUL x y)
 
diff --git a/src/cmd/compile/internal/ssa/rewriteRISCV64.go b/src/cmd/compile/internal/ssa/rewriteRISCV64.go
index 6f949707a1..097232ab18 100644
--- a/src/cmd/compile/internal/ssa/rewriteRISCV64.go
+++ b/src/cmd/compile/internal/ssa/rewriteRISCV64.go
@@ -5530,6 +5530,38 @@ func rewriteValueRISCV64_OpRISCV64SLTI(v *Value) bool {
 		v.AuxInt = int64ToAuxInt(b2i(int64(y) < int64(x)))
 		return true
 	}
+	// match: (SLTI [x] (ANDI [y] _))
+	// cond: y >= 0 && int64(y) < int64(x)
+	// result: (MOVDconst [1])
+	for {
+		x := auxIntToInt64(v.AuxInt)
+		if v_0.Op != OpRISCV64ANDI {
+			break
+		}
+		y := auxIntToInt64(v_0.AuxInt)
+		if !(y >= 0 && int64(y) < int64(x)) {
+			break
+		}
+		v.reset(OpRISCV64MOVDconst)
+		v.AuxInt = int64ToAuxInt(1)
+		return true
+	}
+	// match: (SLTI [x] (ORI [y] _))
+	// cond: y >= 0 && int64(y) >= int64(x)
+	// result: (MOVDconst [0])
+	for {
+		x := auxIntToInt64(v.AuxInt)
+		if v_0.Op != OpRISCV64ORI {
+			break
+		}
+		y := auxIntToInt64(v_0.AuxInt)
+		if !(y >= 0 && int64(y) >= int64(x)) {
+			break
+		}
+		v.reset(OpRISCV64MOVDconst)
+		v.AuxInt = int64ToAuxInt(0)
+		return true
+	}
 	return false
 }
 func rewriteValueRISCV64_OpRISCV64SLTIU(v *Value) bool {
@@ -5546,6 +5578,38 @@ func rewriteValueRISCV64_OpRISCV64SLTIU(v *Value) bool {
 		v.AuxInt = int64ToAuxInt(b2i(uint64(y) < uint64(x)))
 		return true
 	}
+	// match: (SLTIU [x] (ANDI [y] _))
+	// cond: y >= 0 && uint64(y) < uint64(x)
+	// result: (MOVDconst [1])
+	for {
+		x := auxIntToInt64(v.AuxInt)
+		if v_0.Op != OpRISCV64ANDI {
+			break
+		}
+		y := auxIntToInt64(v_0.AuxInt)
+		if !(y >= 0 && uint64(y) < uint64(x)) {
+			break
+		}
+		v.reset(OpRISCV64MOVDconst)
+		v.AuxInt = int64ToAuxInt(1)
+		return true
+	}
+	// match: (SLTIU [x] (ORI [y] _))
+	// cond: y >= 0 && uint64(y) >= uint64(x)
+	// result: (MOVDconst [0])
+	for {
+		x := auxIntToInt64(v.AuxInt)
+		if v_0.Op != OpRISCV64ORI {
+			break
+		}
+		y := auxIntToInt64(v_0.AuxInt)
+		if !(y >= 0 && uint64(y) >= uint64(x)) {
+			break
+		}
+		v.reset(OpRISCV64MOVDconst)
+		v.AuxInt = int64ToAuxInt(0)
+		return true
+	}
 	return false
 }
 func rewriteValueRISCV64_OpRISCV64SLTU(v *Value) bool {
diff --git a/test/codegen/shift.go b/test/codegen/shift.go
index 5a2391358c..c82566bb10 100644
--- a/test/codegen/shift.go
+++ b/test/codegen/shift.go
@@ -11,65 +11,65 @@ package codegen
 // ------------------ //
 
 func lshConst64x64(v int64) int64 {
-	// riscv64:"SLLI",-"AND",-"SLTIU"
-	// ppc64le:"SLD"
 	// ppc64:"SLD"
+	// ppc64le:"SLD"
+	// riscv64:"SLLI",-"AND",-"SLTIU"
 	return v << uint64(33)
 }
 
 func rshConst64Ux64(v uint64) uint64 {
-	// riscv64:"SRLI",-"AND",-"SLTIU"
-	// ppc64le:"SRD"
 	// ppc64:"SRD"
+	// ppc64le:"SRD"
+	// riscv64:"SRLI",-"AND",-"SLTIU"
 	return v >> uint64(33)
 }
 
 func rshConst64x64(v int64) int64 {
-	// riscv64:"SRAI",-"OR",-"SLTIU"
-	// ppc64le:"SRAD"
 	// ppc64:"SRAD"
+	// ppc64le:"SRAD"
+	// riscv64:"SRAI",-"OR",-"SLTIU"
 	return v >> uint64(33)
 }
 
 func lshConst32x64(v int32) int32 {
-	// riscv64:"SLLI",-"AND",-"SLTIU"
-	// ppc64le:"SLW"
 	// ppc64:"SLW"
+	// ppc64le:"SLW"
+	// riscv64:"SLLI",-"AND",-"SLTIU"
 	return v << uint64(29)
 }
 
 func rshConst32Ux64(v uint32) uint32 {
-	// riscv64:"SRLI",-"AND",-"SLTIU"
-	// ppc64le:"SRW"
 	// ppc64:"SRW"
+	// ppc64le:"SRW"
+	// riscv64:"SRLI",-"AND",-"SLTIU"
 	return v >> uint64(29)
 }
 
 func rshConst32x64(v int32) int32 {
-	// riscv64:"SRAI",-"OR",-"SLTIU"
-	// ppc64le:"SRAW"
 	// ppc64:"SRAW"
+	// ppc64le:"SRAW"
+	// riscv64:"SRAI",-"OR",-"SLTIU"
 	return v >> uint64(29)
 }
 
 func lshConst64x32(v int64) int64 {
-	// riscv64:"SLLI",-"AND",-"SLTIU"
-	// ppc64le:"SLD"
 	// ppc64:"SLD"
+	// ppc64le:"SLD"
+	// riscv64:"SLLI",-"AND",-"SLTIU"
 	return v << uint32(33)
 }
 
 func rshConst64Ux32(v uint64) uint64 {
-	// riscv64:"SRLI",-"AND",-"SLTIU"
-	// ppc64le:"SRD"
 	// ppc64:"SRD"
+	// ppc64le:"SRD"
+	// riscv64:"SRLI",-"AND",-"SLTIU"
 	return v >> uint32(33)
 }
 
 func rshConst64x32(v int64) int64 {
-	// riscv64:"SRAI",-"OR",-"SLTIU"
-	// ppc64le:"SRAD"
 	// ppc64:"SRAD"
+	// ppc64le:"SRAD"
+	// riscv64:"SRAI",-"OR",-"SLTIU"
 	return v >> uint32(33)
 }
 
@@ -78,90 +78,90 @@ func rshConst64x32(v int64) int64 {
 // ------------------ //
 
 func lshMask64x64(v int64, s uint64) int64 {
+	// arm64:"LSL",-"AND"
 	// ppc64:"ANDCC",-"ORN",-"ISEL"
 	// ppc64le:"ANDCC",-"ORN",-"ISEL"
 	// riscv64:"SLL",-"AND\t",-"SLTIU"
 	// s390x:-"RISBGZ",-"AND",-"LOCGR"
-	// arm64:"LSL",-"AND"
 	return v << (s & 63)
 }
 
 func rshMask64Ux64(v uint64, s uint64) uint64 {
+	// arm64:"LSR",-"AND",-"CSEL"
 	// ppc64:"ANDCC",-"ORN",-"ISEL"
 	// ppc64le:"ANDCC",-"ORN",-"ISEL"
 	// riscv64:"SRL",-"AND\t",-"SLTIU"
 	// s390x:-"RISBGZ",-"AND",-"LOCGR"
-	// arm64:"LSR",-"AND",-"CSEL"
 	return v >> (s & 63)
 }
 
 func rshMask64x64(v int64, s uint64) int64 {
+	// arm64:"ASR",-"AND",-"CSEL"
 	// ppc64:"ANDCC",-"ORN",-"ISEL"
 	// ppc64le:"ANDCC",-ORN",-"ISEL"
 	// riscv64:"SRA",-"OR",-"SLTIU"
 	// s390x:-"RISBGZ",-"AND",-"LOCGR"
-	// arm64:"ASR",-"AND",-"CSEL"
 	return v >> (s & 63)
 }
 
 func lshMask32x64(v int32, s uint64) int32 {
+	// arm64:"LSL",-"AND"
 	// ppc64:"ISEL",-"ORN"
 	// ppc64le:"ISEL",-"ORN"
-	// riscv64:"SLL","AND","SLTIU"
+	// riscv64:"SLL",-"AND\t",-"SLTIU"
 	// s390x:-"RISBGZ",-"AND",-"LOCGR"
-	// arm64:"LSL",-"AND"
 	return v << (s & 63)
 }
 
 func rshMask32Ux64(v uint32, s uint64) uint32 {
+	// arm64:"LSR",-"AND"
 	// ppc64:"ISEL",-"ORN"
 	// ppc64le:"ISEL",-"ORN"
-	// riscv64:"SRL","AND","SLTIU"
+	// riscv64:"SRL",-"AND\t",-"SLTIU"
 	// s390x:-"RISBGZ",-"AND",-"LOCGR"
-	// arm64:"LSR",-"AND"
 	return v >> (s & 63)
 }
 
 func rshMask32x64(v int32, s uint64) int32 {
+	// arm64:"ASR",-"AND"
 	// ppc64:"ISEL",-"ORN"
 	// ppc64le:"ISEL",-"ORN"
-	// riscv64:"SRA","OR","SLTIU"
+	// riscv64:"SRA",-"OR",-"SLTIU"
 	// s390x:-"RISBGZ",-"AND",-"LOCGR"
-	// arm64:"ASR",-"AND"
 	return v >> (s & 63)
 }
 
 func lshMask64x32(v int64, s uint32) int64 {
+	// arm64:"LSL",-"AND"
 	// ppc64:"ANDCC",-"ORN"
 	// ppc64le:"ANDCC",-"ORN"
 	// riscv64:"SLL",-"AND\t",-"SLTIU"
 	// s390x:-"RISBGZ",-"AND",-"LOCGR"
-	// arm64:"LSL",-"AND"
 	return v << (s & 63)
 }
 
 func rshMask64Ux32(v uint64, s uint32) uint64 {
+	// arm64:"LSR",-"AND",-"CSEL"
 	// ppc64:"ANDCC",-"ORN"
 	// ppc64le:"ANDCC",-"ORN"
 	// riscv64:"SRL",-"AND\t",-"SLTIU"
 	// s390x:-"RISBGZ",-"AND",-"LOCGR"
-	// arm64:"LSR",-"AND",-"CSEL"
 	return v >> (s & 63)
 }
 
 func rshMask64x32(v int64, s uint32) int64 {
+	// arm64:"ASR",-"AND",-"CSEL"
 	// ppc64:"ANDCC",-"ORN",-"ISEL"
 	// ppc64le:"ANDCC",-"ORN",-"ISEL"
 	// riscv64:"SRA",-"OR",-"SLTIU"
 	// s390x:-"RISBGZ",-"AND",-"LOCGR"
-	// arm64:"ASR",-"AND",-"CSEL"
 	return v >> (s & 63)
 }
 
 func lshMask64x32Ext(v int64, s int32) int64 {
 	// ppc64:"ANDCC",-"ORN",-"ISEL"
 	// ppc64le:"ANDCC",-"ORN",-"ISEL"
-	// riscv64:"SLL","AND","SLTIU"
+	// riscv64:"SLL",-"AND\t",-"SLTIU"
 	// s390x:-"RISBGZ",-"AND",-"LOCGR"
 	return v << uint(s&63)
 }
@@ -169,7 +169,7 @@ func lshMask64x32Ext(v int64, s int32) int64 {
 func rshMask64Ux32Ext(v uint64, s int32) uint64 {
 	// ppc64:"ANDCC",-"ORN",-"ISEL"
 	// ppc64le:"ANDCC",-"ORN",-"ISEL"
-	// riscv64:"SRL","AND","SLTIU"
+	// riscv64:"SRL",-"AND\t",-"SLTIU"
 	// s390x:-"RISBGZ",-"AND",-"LOCGR"
 	return v >> uint(s&63)
 }
@@ -177,7 +177,7 @@ func rshMask64Ux32Ext(v uint64, s int32) uint64 {
 func rshMask64x32Ext(v int64, s int32) int64 {
 	// ppc64:"ANDCC",-"ORN",-"ISEL"
 	// ppc64le:"ANDCC",-"ORN",-"ISEL"
-	// riscv64:"SRA","OR","SLTIU"
+	// riscv64:"SRA",-"OR",-"SLTIU"
 	// s390x:-"RISBGZ",-"AND",-"LOCGR"
 	return v >> uint(s&63)
 }