cmd/compile: fix bounds check report

randall77 · randall77 · commit af03343f934b · 2025-09-09T07:37:40.000-07:00
For constant-index, variable length situations. Inadvertant shadowing of the yVal variable. Oops. Fixes #75327 Change-Id: I3403066fc39b7664222a3098cf0f22b5761ea66a Reviewed-on: https://go-review.googlesource.com/c/go/+/702015 Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com> Reviewed-by: David Chase <drchase@google.com> Reviewed-by: Keith Randall <khr@google.com> LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
diff --git a/src/cmd/compile/internal/amd64/ssa.go b/src/cmd/compile/internal/amd64/ssa.go
@@ -1306,7 +1306,7 @@ func ssaGenValue(s *ssagen.State, v *ssa.Value) {
 			}
 		case ssa.OpAMD64LoweredPanicBoundsCR:
 			yIsReg = true
-			yVal := int(v.Args[0].Reg() - x86.REG_AX)
+			yVal = int(v.Args[0].Reg() - x86.REG_AX)
 			c := v.Aux.(ssa.PanicBoundsC).C
 			if c >= 0 && c <= abi.BoundsMaxConst {
 				xVal = int(c)
diff --git a/src/cmd/compile/internal/arm/ssa.go b/src/cmd/compile/internal/arm/ssa.go
@@ -777,7 +777,7 @@ func ssaGenValue(s *ssagen.State, v *ssa.Value) {
 			}
 		case ssa.OpARMLoweredPanicBoundsCR:
 			yIsReg = true
-			yVal := int(v.Args[0].Reg() - arm.REG_R0)
+			yVal = int(v.Args[0].Reg() - arm.REG_R0)
 			c := v.Aux.(ssa.PanicBoundsC).C
 			if c >= 0 && c <= abi.BoundsMaxConst {
 				xVal = int(c)
diff --git a/src/cmd/compile/internal/arm64/ssa.go b/src/cmd/compile/internal/arm64/ssa.go
@@ -1319,7 +1319,7 @@ func ssaGenValue(s *ssagen.State, v *ssa.Value) {
 			}
 		case ssa.OpARM64LoweredPanicBoundsCR:
 			yIsReg = true
-			yVal := int(v.Args[0].Reg() - arm64.REG_R0)
+			yVal = int(v.Args[0].Reg() - arm64.REG_R0)
 			c := v.Aux.(ssa.PanicBoundsC).C
 			if c >= 0 && c <= abi.BoundsMaxConst {
 				xVal = int(c)
diff --git a/src/cmd/compile/internal/loong64/ssa.go b/src/cmd/compile/internal/loong64/ssa.go
@@ -811,7 +811,7 @@ func ssaGenValue(s *ssagen.State, v *ssa.Value) {
 			}
 		case ssa.OpLOONG64LoweredPanicBoundsCR:
 			yIsReg = true
-			yVal := int(v.Args[0].Reg() - loong64.REG_R4)
+			yVal = int(v.Args[0].Reg() - loong64.REG_R4)
 			c := v.Aux.(ssa.PanicBoundsC).C
 			if c >= 0 && c <= abi.BoundsMaxConst {
 				xVal = int(c)
diff --git a/src/cmd/compile/internal/mips/ssa.go b/src/cmd/compile/internal/mips/ssa.go
@@ -551,7 +551,7 @@ func ssaGenValue(s *ssagen.State, v *ssa.Value) {
 			}
 		case ssa.OpMIPSLoweredPanicBoundsCR:
 			yIsReg = true
-			yVal := int(v.Args[0].Reg() - mips.REG_R1)
+			yVal = int(v.Args[0].Reg() - mips.REG_R1)
 			c := v.Aux.(ssa.PanicBoundsC).C
 			if c >= 0 && c <= abi.BoundsMaxConst {
 				xVal = int(c)
diff --git a/src/cmd/compile/internal/mips64/ssa.go b/src/cmd/compile/internal/mips64/ssa.go
@@ -542,7 +542,7 @@ func ssaGenValue(s *ssagen.State, v *ssa.Value) {
 			}
 		case ssa.OpMIPS64LoweredPanicBoundsCR:
 			yIsReg = true
-			yVal := int(v.Args[0].Reg() - mips.REG_R1)
+			yVal = int(v.Args[0].Reg() - mips.REG_R1)
 			c := v.Aux.(ssa.PanicBoundsC).C
 			if c >= 0 && c <= abi.BoundsMaxConst {
 				xVal = int(c)
diff --git a/src/cmd/compile/internal/ppc64/ssa.go b/src/cmd/compile/internal/ppc64/ssa.go
@@ -1947,7 +1947,7 @@ func ssaGenValue(s *ssagen.State, v *ssa.Value) {
 			}
 		case ssa.OpPPC64LoweredPanicBoundsCR:
 			yIsReg = true
-			yVal := int(v.Args[0].Reg() - ppc64.REG_R3)
+			yVal = int(v.Args[0].Reg() - ppc64.REG_R3)
 			c := v.Aux.(ssa.PanicBoundsC).C
 			if c >= 0 && c <= abi.BoundsMaxConst {
 				xVal = int(c)
diff --git a/src/cmd/compile/internal/riscv64/ssa.go b/src/cmd/compile/internal/riscv64/ssa.go
@@ -544,7 +544,7 @@ func ssaGenValue(s *ssagen.State, v *ssa.Value) {
 			}
 		case ssa.OpRISCV64LoweredPanicBoundsCR:
 			yIsReg = true
-			yVal := int(v.Args[0].Reg() - riscv.REG_X5)
+			yVal = int(v.Args[0].Reg() - riscv.REG_X5)
 			c := v.Aux.(ssa.PanicBoundsC).C
 			if c >= 0 && c <= abi.BoundsMaxConst {
 				xVal = int(c)
diff --git a/src/cmd/compile/internal/s390x/ssa.go b/src/cmd/compile/internal/s390x/ssa.go
@@ -608,7 +608,7 @@ func ssaGenValue(s *ssagen.State, v *ssa.Value) {
 			}
 		case ssa.OpS390XLoweredPanicBoundsCR:
 			yIsReg = true
-			yVal := int(v.Args[0].Reg() - s390x.REG_R0)
+			yVal = int(v.Args[0].Reg() - s390x.REG_R0)
 			c := v.Aux.(ssa.PanicBoundsC).C
 			if c >= 0 && c <= abi.BoundsMaxConst {
 				xVal = int(c)
diff --git a/src/cmd/compile/internal/x86/ssa.go b/src/cmd/compile/internal/x86/ssa.go
@@ -804,7 +804,7 @@ func ssaGenValue(s *ssagen.State, v *ssa.Value) {
 			}
 		case ssa.Op386LoweredPanicBoundsCR:
 			yIsReg = true
-			yVal := int(v.Args[0].Reg() - x86.REG_AX)
+			yVal = int(v.Args[0].Reg() - x86.REG_AX)
 			c := v.Aux.(ssa.PanicBoundsC).C
 			if c >= 0 && c <= abi.BoundsMaxConst {
 				xVal = int(c)
diff --git a/test/fixedbugs/issue75327.go b/test/fixedbugs/issue75327.go
@@ -0,0 +1,33 @@
+// run
+
+package main
+
+import (
+	"fmt"
+	"strings"
+)
+
+func main() {
+	defer func() {
+		err := recover()
+		txt := fmt.Sprintf("%s", err)
+		if !strings.HasSuffix(txt, "with length 1") {
+			panic("bad error: " + txt)
+		}
+	}()
+	foo([]uint64{0})
+}
+
+//go:noinline
+func foo(haystack []uint64) {
+	for n := range len(haystack) {
+		_ = n
+		_ = haystack[1]
+	}
+
+	xxx := haystack[0:len(haystack)]
+	sink(xxx)
+}
+
+//go:noinline
+func sink([]uint64) {}

Original file line number	Diff line number	Diff line change
`@@ -1306,7 +1306,7 @@ func ssaGenValue(s ssagen.State, v ssa.Value) {`
`1306`	`1306`	`}`
`1307`	`1307`	`case ssa.OpAMD64LoweredPanicBoundsCR:`
`1308`	`1308`	`yIsReg = true`
`1309`		`- yVal := int(v.Args[0].Reg() - x86.REG_AX)`
	`1309`	`+ yVal = int(v.Args[0].Reg() - x86.REG_AX)`
`1310`	`1310`	`c := v.Aux.(ssa.PanicBoundsC).C`
`1311`	`1311`	`if c >= 0 && c <= abi.BoundsMaxConst {`
`1312`	`1312`	`xVal = int(c)`
Original file line number	Diff line number	Diff line change
`@@ -777,7 +777,7 @@ func ssaGenValue(s ssagen.State, v ssa.Value) {`
`777`	`777`	`}`
`778`	`778`	`case ssa.OpARMLoweredPanicBoundsCR:`
`779`	`779`	`yIsReg = true`
`780`		`- yVal := int(v.Args[0].Reg() - arm.REG_R0)`
	`780`	`+ yVal = int(v.Args[0].Reg() - arm.REG_R0)`
`781`	`781`	`c := v.Aux.(ssa.PanicBoundsC).C`
`782`	`782`	`if c >= 0 && c <= abi.BoundsMaxConst {`
`783`	`783`	`xVal = int(c)`
Original file line number	Diff line number	Diff line change
`@@ -1319,7 +1319,7 @@ func ssaGenValue(s ssagen.State, v ssa.Value) {`
`1319`	`1319`	`}`
`1320`	`1320`	`case ssa.OpARM64LoweredPanicBoundsCR:`
`1321`	`1321`	`yIsReg = true`
`1322`		`- yVal := int(v.Args[0].Reg() - arm64.REG_R0)`
	`1322`	`+ yVal = int(v.Args[0].Reg() - arm64.REG_R0)`
`1323`	`1323`	`c := v.Aux.(ssa.PanicBoundsC).C`
`1324`	`1324`	`if c >= 0 && c <= abi.BoundsMaxConst {`
`1325`	`1325`	`xVal = int(c)`
Original file line number	Diff line number	Diff line change
`@@ -811,7 +811,7 @@ func ssaGenValue(s ssagen.State, v ssa.Value) {`
`811`	`811`	`}`
`812`	`812`	`case ssa.OpLOONG64LoweredPanicBoundsCR:`
`813`	`813`	`yIsReg = true`
`814`		`- yVal := int(v.Args[0].Reg() - loong64.REG_R4)`
	`814`	`+ yVal = int(v.Args[0].Reg() - loong64.REG_R4)`
`815`	`815`	`c := v.Aux.(ssa.PanicBoundsC).C`
`816`	`816`	`if c >= 0 && c <= abi.BoundsMaxConst {`
`817`	`817`	`xVal = int(c)`
Original file line number	Diff line number	Diff line change
`@@ -551,7 +551,7 @@ func ssaGenValue(s ssagen.State, v ssa.Value) {`
`551`	`551`	`}`
`552`	`552`	`case ssa.OpMIPSLoweredPanicBoundsCR:`
`553`	`553`	`yIsReg = true`
`554`		`- yVal := int(v.Args[0].Reg() - mips.REG_R1)`
	`554`	`+ yVal = int(v.Args[0].Reg() - mips.REG_R1)`
`555`	`555`	`c := v.Aux.(ssa.PanicBoundsC).C`
`556`	`556`	`if c >= 0 && c <= abi.BoundsMaxConst {`
`557`	`557`	`xVal = int(c)`
Original file line number	Diff line number	Diff line change
`@@ -542,7 +542,7 @@ func ssaGenValue(s ssagen.State, v ssa.Value) {`
`542`	`542`	`}`
`543`	`543`	`case ssa.OpMIPS64LoweredPanicBoundsCR:`
`544`	`544`	`yIsReg = true`
`545`		`- yVal := int(v.Args[0].Reg() - mips.REG_R1)`
	`545`	`+ yVal = int(v.Args[0].Reg() - mips.REG_R1)`
`546`	`546`	`c := v.Aux.(ssa.PanicBoundsC).C`
`547`	`547`	`if c >= 0 && c <= abi.BoundsMaxConst {`
`548`	`548`	`xVal = int(c)`
Original file line number	Diff line number	Diff line change
`@@ -1947,7 +1947,7 @@ func ssaGenValue(s ssagen.State, v ssa.Value) {`
`1947`	`1947`	`}`
`1948`	`1948`	`case ssa.OpPPC64LoweredPanicBoundsCR:`
`1949`	`1949`	`yIsReg = true`
`1950`		`- yVal := int(v.Args[0].Reg() - ppc64.REG_R3)`
	`1950`	`+ yVal = int(v.Args[0].Reg() - ppc64.REG_R3)`
`1951`	`1951`	`c := v.Aux.(ssa.PanicBoundsC).C`
`1952`	`1952`	`if c >= 0 && c <= abi.BoundsMaxConst {`
`1953`	`1953`	`xVal = int(c)`
Original file line number	Diff line number	Diff line change
`@@ -544,7 +544,7 @@ func ssaGenValue(s ssagen.State, v ssa.Value) {`
`544`	`544`	`}`
`545`	`545`	`case ssa.OpRISCV64LoweredPanicBoundsCR:`
`546`	`546`	`yIsReg = true`
`547`		`- yVal := int(v.Args[0].Reg() - riscv.REG_X5)`
	`547`	`+ yVal = int(v.Args[0].Reg() - riscv.REG_X5)`
`548`	`548`	`c := v.Aux.(ssa.PanicBoundsC).C`
`549`	`549`	`if c >= 0 && c <= abi.BoundsMaxConst {`
`550`	`550`	`xVal = int(c)`
Original file line number	Diff line number	Diff line change
`@@ -608,7 +608,7 @@ func ssaGenValue(s ssagen.State, v ssa.Value) {`
`608`	`608`	`}`
`609`	`609`	`case ssa.OpS390XLoweredPanicBoundsCR:`
`610`	`610`	`yIsReg = true`
`611`		`- yVal := int(v.Args[0].Reg() - s390x.REG_R0)`
	`611`	`+ yVal = int(v.Args[0].Reg() - s390x.REG_R0)`
`612`	`612`	`c := v.Aux.(ssa.PanicBoundsC).C`
`613`	`613`	`if c >= 0 && c <= abi.BoundsMaxConst {`
`614`	`614`	`xVal = int(c)`
Original file line number	Diff line number	Diff line change
`@@ -804,7 +804,7 @@ func ssaGenValue(s ssagen.State, v ssa.Value) {`
`804`	`804`	`}`
`805`	`805`	`case ssa.Op386LoweredPanicBoundsCR:`
`806`	`806`	`yIsReg = true`
`807`		`- yVal := int(v.Args[0].Reg() - x86.REG_AX)`
	`807`	`+ yVal = int(v.Args[0].Reg() - x86.REG_AX)`
`808`	`808`	`c := v.Aux.(ssa.PanicBoundsC).C`
`809`	`809`	`if c >= 0 && c <= abi.BoundsMaxConst {`
`810`	`810`	`xVal = int(c)`