issue14553.go

     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  
    10  package main
    11  
    12  import (
    13  	"fmt"
    14  	"math"
    15  )
    16  
    17  func 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
View as plain text