test/fixedbugs: add more test cases to issue #27718

This CL add test cases for the unary FP negative
operation.

Change-Id: I54e7292ca9df05da0c2b113adefc97ee1e94c6e2
Reviewed-on: https://go-review.googlesource.com/c/go/+/190937
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>

diff --git a/test/fixedbugs/issue27718.go b/test/fixedbugs/issue27718.go
index f7794182f588d6e43d62dd0e503139ea5e8abaea..ff616fb0f29043f183c6a0aaeb85ffaa3c8ed3c9 100644 (file)
--- a/test/fixedbugs/issue27718.go
+++ b/test/fixedbugs/issue27718.go
@@ -36,6 +36,20 @@ func testSub64() {
        }
 }
 
+//go:noinline
+func neg64(x float64) float64 {
+       return -x
+}
+
+func testNeg64() {
+       var zero float64
+       inf := 1.0 / zero
+       negZero := -1 / inf
+       if 1/neg64(negZero) != inf {
+               panic("-negZero != posZero (64 bit)")
+       }
+}
+
 //go:noinline
 func add32(x float32) float32 {
        return x + 0
@@ -64,9 +78,25 @@ func testSub32() {
        }
 }
 
+//go:noinline
+func neg32(x float32) float32 {
+       return -x
+}
+
+func testNeg32() {
+       var zero float32
+       inf := 1.0 / zero
+       negZero := -1 / inf
+       if 1/neg32(negZero) != inf {
+               panic("-negZero != posZero (32 bit)")
+       }
+}
+
 func main() {
        testAdd64()
        testSub64()
+       testNeg64()
        testAdd32()
        testSub32()
+       testNeg32()
 }