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// asmcheck
// 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 codegen
func cmovint(c int) int {
x := c + 4
if x < 0 {
x = 182
}
// amd64:"CMOVQLT"
// arm64:"CSEL\tLT"
return x
}
func cmovchan(x, y chan int) chan int {
if x != y {
x = y
}
// amd64:"CMOVQNE"
// arm64:"CSEL\tNE"
return x
}
func cmovuintptr(x, y uintptr) uintptr {
if x < y {
x = -y
}
// amd64:"CMOVQCS"
// arm64:"CSEL\tLO"
return x
}
func cmov32bit(x, y uint32) uint32 {
if x < y {
x = -y
}
// amd64:"CMOVLCS"
// arm64:"CSEL\tLO"
return x
}
func cmov16bit(x, y uint16) uint16 {
if x < y {
x = -y
}
// amd64:"CMOVWCS"
// arm64:"CSEL\tLO"
return x
}
// Floating point comparison. For EQ/NE, we must
// generate special code to handle NaNs.
func cmovfloateq(x, y float64) int {
a := 128
if x == y {
a = 256
}
// amd64:"CMOVQNE","CMOVQPC"
// arm64:"CSEL\tEQ"
return a
}
func cmovfloatne(x, y float64) int {
a := 128
if x != y {
a = 256
}
// amd64:"CMOVQNE","CMOVQPS"
// arm64:"CSEL\tNE"
return a
}
//go:noinline
func frexp(f float64) (frac float64, exp int) {
return 1.0, 4
}
//go:noinline
func ldexp(frac float64, exp int) float64 {
return 1.0
}
// Generate a CMOV with a floating comparison and integer move.
func cmovfloatint2(x, y float64) float64 {
yfr, yexp := 4.0, 5
r := x
for r >= y {
rfr, rexp := frexp(r)
if rfr < yfr {
rexp = rexp - 1
}
// amd64:"CMOVQHI"
// arm64:"CSEL\tGT"
r = r - ldexp(y, (rexp-yexp))
}
return r
}
func cmovloaded(x [4]int, y int) int {
if x[2] != 0 {
y = x[2]
} else {
y = y >> 2
}
// amd64:"CMOVQNE"
// arm64:"CSEL\tNE"
return y
}
func cmovuintptr2(x, y uintptr) uintptr {
a := x * 2
if a == 0 {
a = 256
}
// amd64:"CMOVQEQ"
// arm64:"CSEL\tEQ"
return a
}
// Floating point CMOVs are not supported by amd64/arm64
func cmovfloatmove(x, y int) float64 {
a := 1.0
if x <= y {
a = 2.0
}
// amd64:-"CMOV"
// arm64:-"CSEL"
return a
}
// On amd64, the following patterns trigger comparison inversion.
// Test that we correctly invert the CMOV condition
var gsink int64
var gusink uint64
func cmovinvert1(x, y int64) int64 {
if x < gsink {
y = -y
}
// amd64:"CMOVQGT"
return y
}
func cmovinvert2(x, y int64) int64 {
if x <= gsink {
y = -y
}
// amd64:"CMOVQGE"
return y
}
func cmovinvert3(x, y int64) int64 {
if x == gsink {
y = -y
}
// amd64:"CMOVQEQ"
return y
}
func cmovinvert4(x, y int64) int64 {
if x != gsink {
y = -y
}
// amd64:"CMOVQNE"
return y
}
func cmovinvert5(x, y uint64) uint64 {
if x > gusink {
y = -y
}
// amd64:"CMOVQCS"
return y
}
func cmovinvert6(x, y uint64) uint64 {
if x >= gusink {
y = -y
}
// amd64:"CMOVQLS"
return y
}
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