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// Copyright 2023 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 runtime
import "unsafe"
func strmin(x, y string) string {
if y < x {
return y
}
return x
}
func strmax(x, y string) string {
if y > x {
return y
}
return x
}
func fmin32(x, y float32) float32 { return fmin(x, y) }
func fmin64(x, y float64) float64 { return fmin(x, y) }
func fmax32(x, y float32) float32 { return fmax(x, y) }
func fmax64(x, y float64) float64 { return fmax(x, y) }
type floaty interface{ ~float32 | ~float64 }
func fmin[F floaty](x, y F) F {
if y != y || y < x {
return y
}
if x != x || x < y || x != 0 {
return x
}
// x and y are both ±0
// if either is -0, return -0; else return +0
return forbits(x, y)
}
func fmax[F floaty](x, y F) F {
if y != y || y > x {
return y
}
if x != x || x > y || x != 0 {
return x
}
// x and y are both ±0
// if both are -0, return -0; else return +0
return fandbits(x, y)
}
func forbits[F floaty](x, y F) F {
switch unsafe.Sizeof(x) {
case 4:
*(*uint32)(unsafe.Pointer(&x)) |= *(*uint32)(unsafe.Pointer(&y))
case 8:
*(*uint64)(unsafe.Pointer(&x)) |= *(*uint64)(unsafe.Pointer(&y))
}
return x
}
func fandbits[F floaty](x, y F) F {
switch unsafe.Sizeof(x) {
case 4:
*(*uint32)(unsafe.Pointer(&x)) &= *(*uint32)(unsafe.Pointer(&y))
case 8:
*(*uint64)(unsafe.Pointer(&x)) &= *(*uint64)(unsafe.Pointer(&y))
}
return x
}
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