go source for verification 2026-05-22

test/fixedbugs/issue13171.go

@@ -0,0 +1,34 @@
+// run
+
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+// Make sure the compiler knows that DUFFCOPY clobbers X0
+
+import "fmt"
+
+//go:noinline
+func f(x float64) float64 {
+	// y is allocated to X0
+	y := x + 5
+	// marshals z before y.  Marshaling z
+	// calls DUFFCOPY.
+	return g(z, y)
+}
+
+//go:noinline
+func g(b [64]byte, y float64) float64 {
+	return y
+}
+
+var z [64]byte
+
+func main() {
+	got := f(5)
+	if got != 10 {
+		panic(fmt.Sprintf("want 10, got %f", got))
+	}
+}