code review 4798062: 6g, 8g: divide corner case

test/divide.go

+// $G $D/$F.go && $L $F.$A && ./$A.out
+
+// Copyright 2011 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.
+
+// divide corner cases
+
+package main
+
+import "fmt"
+
+func f8(x, y, q, r int8) {
+        if t := x / y; t != q {
+                fmt.Printf("%d/%d = %d, want %d\n", x, y, t, q)
+        }
+        if t := x % y; t != r {
+                fmt.Printf("%d%%%d = %d, want %d\n", x, y, t, r)
+        }
+}
+
+func f16(x, y, q, r int16) {
+        if t := x / y; t != q {
+                fmt.Printf("%d/%d = %d, want %d\n", x, y, t, q)
+        }
+        if t := x % y; t != r {
+                fmt.Printf("%d%%%d = %d, want %d\n", x, y, t, r)
+        }
+}
+
+func f32(x, y, q, r int32) {
+        if t := x / y; t != q {
+                fmt.Printf("%d/%d = %d, want %d\n", x, y, t, q)
+        }
+        if t := x % y; t != r {
+                fmt.Printf("%d%%%d = %d, want %d\n", x, y, t, r)
+        }
+}
+
+func f64(x, y, q, r int64) {
+        if t := x / y; t != q {
+                fmt.Printf("%d/%d = %d, want %d\n", x, y, t, q)
+        }
+        if t := x % y; t != r {
+                fmt.Printf("%d%%%d = %d, want %d\n", x, y, t, r)
+        }
+}
+
+func main() {
+        f8(-1<<7, -1, -1<<7, 0)
+        f16(-1<<15, -1, -1<<15, 0)
+        f32(-1<<31, -1, -1<<31, 0)
+        f64(-1<<63, -1, -1<<63, 0)
+}