1// run
2
3// Copyright 2016 The Go Authors. All rights reserved.
4// Use of this source code is governed by a BSD-style
5// license that can be found in the LICENSE file.
6
7// This test checks if the compiler's internal constant
8// arithmetic correctly rounds denormal float32 values.
9
10package main
11
12import (
13	"fmt"
14	"math"
15)
16
17func main() {
18	for _, t := range []struct {
19		value float32
20		bits  uint32
21	}{
22		{0e+00, 0x00000000},
23		{1e-46, 0x00000000},
24		{0.5e-45, 0x00000000},
25		{0.8e-45, 0x00000001},
26		{1e-45, 0x00000001},
27		{2e-45, 0x00000001},
28		{3e-45, 0x00000002},
29		{4e-45, 0x00000003},
30		{5e-45, 0x00000004},
31		{6e-45, 0x00000004},
32		{7e-45, 0x00000005},
33		{8e-45, 0x00000006},
34		{9e-45, 0x00000006},
35		{1.0e-44, 0x00000007},
36		{1.1e-44, 0x00000008},
37		{1.2e-44, 0x00000009},
38	} {
39		got := math.Float32bits(t.value)
40		want := t.bits
41		if got != want {
42			panic(fmt.Sprintf("bits(%g) = 0x%08x; want 0x%08x", t.value, got, want))
43		}
44	}
45}
46