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// run
// Copyright 2018 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
import (
"math"
)
type S struct {
u int64
n int32
}
func F1(f float64) *S {
s := f
pf := math.Copysign(f, 1)
u := math.Floor(pf)
return &S{
u: int64(math.Copysign(u, s)),
n: int32(math.Copysign((pf-u)*1e9, s)),
}
}
func F2(f float64) *S {
s := f
f = math.Copysign(f, 1)
u := math.Floor(f)
return &S{
u: int64(math.Copysign(u, s)),
n: int32(math.Copysign((f-u)*1e9, s)),
}
}
func main() {
s1 := F1(-1)
s2 := F2(-1)
if *s1 != *s2 {
println("F1:", s1.u, s1.n)
println("F2:", s2.u, s2.n)
panic("different")
}
}
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