go comparisons 源码

  • 2022-07-15
  • 浏览 (1006)

golang comparisons 代码

文件路径:/test/codegen/comparisons.go

// 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

import "unsafe"

// This file contains code generation tests related to the comparison
// operators.

// -------------- //
//    Equality    //
// -------------- //

// Check that compare to constant string use 2/4/8 byte compares

func CompareString1(s string) bool {
	// amd64:`CMPW\t\(.*\), [$]`
	// arm64:`MOVHU\t\(.*\), [R]`,`CMPW\t[$]`
	// ppc64le:`MOVHZ\t\(.*\), [R]`,`CMPW\t.*, [$]`
	// s390x:`MOVHBR\t\(.*\), [R]`,`CMPW\t.*, [$]`
	return s == "xx"
}

func CompareString2(s string) bool {
	// amd64:`CMPL\t\(.*\), [$]`
	// arm64:`MOVWU\t\(.*\), [R]`,`CMPW\t.*, [R]`
	// ppc64le:`MOVWZ\t\(.*\), [R]`,`CMPW\t.*, [R]`
	// s390x:`MOVWBR\t\(.*\), [R]`,`CMPW\t.*, [$]`
	return s == "xxxx"
}

func CompareString3(s string) bool {
	// amd64:`CMPQ\t\(.*\), [A-Z]`
	// arm64:-`CMPW\t`
	// ppc64:-`CMPW\t`
	// ppc64le:-`CMPW\t`
	// s390x:-`CMPW\t`
	return s == "xxxxxxxx"
}

// Check that arrays compare use 2/4/8 byte compares

func CompareArray1(a, b [2]byte) bool {
	// amd64:`CMPW\tcommand-line-arguments[.+_a-z0-9]+\(SP\), [A-Z]`
	// arm64:-`MOVBU\t`
	// ppc64le:-`MOVBZ\t`
	// s390x:-`MOVBZ\t`
	return a == b
}

func CompareArray2(a, b [3]uint16) bool {
	// amd64:`CMPL\tcommand-line-arguments[.+_a-z0-9]+\(SP\), [A-Z]`
	// amd64:`CMPW\tcommand-line-arguments[.+_a-z0-9]+\(SP\), [A-Z]`
	return a == b
}

func CompareArray3(a, b [3]int16) bool {
	// amd64:`CMPL\tcommand-line-arguments[.+_a-z0-9]+\(SP\), [A-Z]`
	// amd64:`CMPW\tcommand-line-arguments[.+_a-z0-9]+\(SP\), [A-Z]`
	return a == b
}

func CompareArray4(a, b [12]int8) bool {
	// amd64:`CMPQ\tcommand-line-arguments[.+_a-z0-9]+\(SP\), [A-Z]`
	// amd64:`CMPL\tcommand-line-arguments[.+_a-z0-9]+\(SP\), [A-Z]`
	return a == b
}

func CompareArray5(a, b [15]byte) bool {
	// amd64:`CMPQ\tcommand-line-arguments[.+_a-z0-9]+\(SP\), [A-Z]`
	return a == b
}

// This was a TODO in mapaccess1_faststr
func CompareArray6(a, b unsafe.Pointer) bool {
	// amd64:`CMPL\t\(.*\), [A-Z]`
	// arm64:`MOVWU\t\(.*\), [R]`,`CMPW\t.*, [R]`
	// ppc64le:`MOVWZ\t\(.*\), [R]`,`CMPW\t.*, [R]`
	// s390x:`MOVWBR\t\(.*\), [R]`,`CMPW\t.*, [R]`
	return *((*[4]byte)(a)) != *((*[4]byte)(b))
}

// -------------- //
//    Ordering    //
// -------------- //

// Test that LEAQ/ADDQconst are folded into SETx ops

var r bool

func CmpFold(x uint32) {
	// amd64:`SETHI\t.*\(SB\)`
	r = x > 4
}

// Test that direct comparisons with memory are generated when
// possible

func CmpMem1(p int, q *int) bool {
	// amd64:`CMPQ\t\(.*\), [A-Z]`
	return p < *q
}

func CmpMem2(p *int, q int) bool {
	// amd64:`CMPQ\t\(.*\), [A-Z]`
	return *p < q
}

func CmpMem3(p *int) bool {
	// amd64:`CMPQ\t\(.*\), [$]7`
	return *p < 7
}

func CmpMem4(p *int) bool {
	// amd64:`CMPQ\t\(.*\), [$]7`
	return 7 < *p
}

func CmpMem5(p **int) {
	// amd64:`CMPL\truntime.writeBarrier\(SB\), [$]0`
	*p = nil
}

func CmpMem6(a []int) int {
	// 386:`CMPL\s8\([A-Z]+\),`
	// amd64:`CMPQ\s16\([A-Z]+\),`
	if a[1] > a[2] {
		return 1
	} else {
		return 2
	}
}

// Check tbz/tbnz are generated when comparing against zero on arm64

func CmpZero1(a int32, ptr *int) {
	if a < 0 { // arm64:"TBZ"
		*ptr = 0
	}
}

func CmpZero2(a int64, ptr *int) {
	if a < 0 { // arm64:"TBZ"
		*ptr = 0
	}
}

func CmpZero3(a int32, ptr *int) {
	if a >= 0 { // arm64:"TBNZ"
		*ptr = 0
	}
}

func CmpZero4(a int64, ptr *int) {
	if a >= 0 { // arm64:"TBNZ"
		*ptr = 0
	}
}

func CmpToZero(a, b, d int32, e, f int64, deOptC0, deOptC1 bool) int32 {
	// arm:`TST`,-`AND`
	// arm64:`TSTW`,-`AND`
	// 386:`TESTL`,-`ANDL`
	// amd64:`TESTL`,-`ANDL`
	c0 := a&b < 0
	// arm:`CMN`,-`ADD`
	// arm64:`CMNW`,-`ADD`
	c1 := a+b < 0
	// arm:`TEQ`,-`XOR`
	c2 := a^b < 0
	// arm64:`TST`,-`AND`
	// amd64:`TESTQ`,-`ANDQ`
	c3 := e&f < 0
	// arm64:`CMN`,-`ADD`
	c4 := e+f < 0
	// not optimized to single CMNW/CMN due to further use of b+d
	// arm64:`ADD`,-`CMNW`
	// arm:`ADD`,-`CMN`
	c5 := b+d == 0
	// not optimized to single TSTW/TST due to further use of a&d
	// arm64:`AND`,-`TSTW`
	// arm:`AND`,-`TST`
	// 386:`ANDL`
	c6 := a&d >= 0
	// arm64:`TST\sR[0-9]+<<3,\sR[0-9]+`
	c7 := e&(f<<3) < 0
	// arm64:`CMN\sR[0-9]+<<3,\sR[0-9]+`
	c8 := e+(f<<3) < 0
	if c0 {
		return 1
	} else if c1 {
		return 2
	} else if c2 {
		return 3
	} else if c3 {
		return 4
	} else if c4 {
		return 5
	} else if c5 {
		return 6
	} else if c6 {
		return 7
	} else if c7 {
		return 9
	} else if c8 {
		return 10
	} else if deOptC0 {
		return b + d
	} else if deOptC1 {
		return a & d
	} else {
		return 0
	}
}

func CmpLogicalToZero(a, b, c uint32, d, e uint64) uint64 {

	// ppc64:"ANDCC",-"CMPW"
	// ppc64le:"ANDCC",-"CMPW"
	// wasm:"I64Eqz",-"I32Eqz",-"I64ExtendI32U",-"I32WrapI64"
	if a&63 == 0 {
		return 1
	}

	// ppc64:"ANDCC",-"CMP"
	// ppc64le:"ANDCC",-"CMP"
	// wasm:"I64Eqz",-"I32Eqz",-"I64ExtendI32U",-"I32WrapI64"
	if d&255 == 0 {
		return 1
	}

	// ppc64:"ANDCC",-"CMP"
	// ppc64le:"ANDCC",-"CMP"
	// wasm:"I64Eqz",-"I32Eqz",-"I64ExtendI32U",-"I32WrapI64"
	if d&e == 0 {
		return 1
	}
	// ppc64:"ORCC",-"CMP"
	// ppc64le:"ORCC",-"CMP"
	// wasm:"I64Eqz",-"I32Eqz",-"I64ExtendI32U",-"I32WrapI64"
	if d|e == 0 {
		return 1
	}

	// ppc64:"XORCC",-"CMP"
	// ppc64le:"XORCC",-"CMP"
	// wasm:"I64Eqz","I32Eqz",-"I64ExtendI32U",-"I32WrapI64"
	if e^d == 0 {
		return 1
	}
	return 0
}

// The following CmpToZero_ex* check that cmp|cmn with bmi|bpl are generated for
// 'comparing to zero' expressions

// var + const
// 'x-const' might be canonicalized to 'x+(-const)', so we check both
// CMN and CMP for subtraction expressions to make the pattern robust.
func CmpToZero_ex1(a int64, e int32) int {
	// arm64:`CMN`,-`ADD`,`(BMI|BPL)`
	if a+3 < 0 {
		return 1
	}

	// arm64:`CMN`,-`ADD`,`BEQ`,`(BMI|BPL)`
	if a+5 <= 0 {
		return 1
	}

	// arm64:`CMN`,-`ADD`,`(BMI|BPL)`
	if a+13 >= 0 {
		return 2
	}

	// arm64:`CMP|CMN`,-`(ADD|SUB)`,`(BMI|BPL)`
	if a-7 < 0 {
		return 3
	}

	// arm64:`CMP|CMN`,-`(ADD|SUB)`,`(BMI|BPL)`
	if a-11 >= 0 {
		return 4
	}

	// arm64:`CMP|CMN`,-`(ADD|SUB)`,`BEQ`,`(BMI|BPL)`
	if a-19 > 0 {
		return 4
	}

	// arm64:`CMNW`,-`ADDW`,`(BMI|BPL)`
	// arm:`CMN`,-`ADD`,`(BMI|BPL)`
	if e+3 < 0 {
		return 5
	}

	// arm64:`CMNW`,-`ADDW`,`(BMI|BPL)`
	// arm:`CMN`,-`ADD`,`(BMI|BPL)`
	if e+13 >= 0 {
		return 6
	}

	// arm64:`CMPW|CMNW`,`(BMI|BPL)`
	// arm:`CMP|CMN`, -`(ADD|SUB)`, `(BMI|BPL)`
	if e-7 < 0 {
		return 7
	}

	// arm64:`CMPW|CMNW`,`(BMI|BPL)`
	// arm:`CMP|CMN`, -`(ADD|SUB)`, `(BMI|BPL)`
	if e-11 >= 0 {
		return 8
	}

	return 0
}

// var + var
// TODO: optimize 'var - var'
func CmpToZero_ex2(a, b, c int64, e, f, g int32) int {
	// arm64:`CMN`,-`ADD`,`(BMI|BPL)`
	if a+b < 0 {
		return 1
	}

	// arm64:`CMN`,-`ADD`,`BEQ`,`(BMI|BPL)`
	if a+c <= 0 {
		return 1
	}

	// arm64:`CMN`,-`ADD`,`(BMI|BPL)`
	if b+c >= 0 {
		return 2
	}

	// arm64:`CMNW`,-`ADDW`,`(BMI|BPL)`
	// arm:`CMN`,-`ADD`,`(BMI|BPL)`
	if e+f < 0 {
		return 5
	}

	// arm64:`CMNW`,-`ADDW`,`(BMI|BPL)`
	// arm:`CMN`,-`ADD`,`(BMI|BPL)`
	if f+g >= 0 {
		return 6
	}
	return 0
}

// var + var*var
func CmpToZero_ex3(a, b, c, d int64, e, f, g, h int32) int {
	// arm64:`CMN`,-`MADD`,`MUL`,`(BMI|BPL)`
	if a+b*c < 0 {
		return 1
	}

	// arm64:`CMN`,-`MADD`,`MUL`,`(BMI|BPL)`
	if b+c*d >= 0 {
		return 2
	}

	// arm64:`CMNW`,-`MADDW`,`MULW`,`BEQ`,`(BMI|BPL)`
	// arm:`CMN`,-`MULA`,`MUL`,`BEQ`,`(BMI|BPL)`
	if e+f*g > 0 {
		return 5
	}

	// arm64:`CMNW`,-`MADDW`,`MULW`,`BEQ`,`(BMI|BPL)`
	// arm:`CMN`,-`MULA`,`MUL`,`BEQ`,`(BMI|BPL)`
	if f+g*h <= 0 {
		return 6
	}
	return 0
}

// var - var*var
func CmpToZero_ex4(a, b, c, d int64, e, f, g, h int32) int {
	// arm64:`CMP`,-`MSUB`,`MUL`,`BEQ`,`(BMI|BPL)`
	if a-b*c > 0 {
		return 1
	}

	// arm64:`CMP`,-`MSUB`,`MUL`,`(BMI|BPL)`
	if b-c*d >= 0 {
		return 2
	}

	// arm64:`CMPW`,-`MSUBW`,`MULW`,`(BMI|BPL)`
	if e-f*g < 0 {
		return 5
	}

	// arm64:`CMPW`,-`MSUBW`,`MULW`,`(BMI|BPL)`
	if f-g*h >= 0 {
		return 6
	}
	return 0
}

func CmpToZero_ex5(e, f int32, u uint32) int {
	// arm:`CMN`,-`ADD`,`BEQ`,`(BMI|BPL)`
	if e+f<<1 > 0 {
		return 1
	}

	// arm:`CMP`,-`SUB`,`(BMI|BPL)`
	if f-int32(u>>2) >= 0 {
		return 2
	}
	return 0
}
func UintLtZero(a uint8, b uint16, c uint32, d uint64) int {
	// amd64: -`(TESTB|TESTW|TESTL|TESTQ|JCC|JCS)`
	// arm64: -`(CMPW|CMP|BHS|BLO)`
	if a < 0 || b < 0 || c < 0 || d < 0 {
		return 1
	}
	return 0
}

func UintGeqZero(a uint8, b uint16, c uint32, d uint64) int {
	// amd64: -`(TESTB|TESTW|TESTL|TESTQ|JCS|JCC)`
	// arm64: -`(CMPW|CMP|BLO|BHS)`
	if a >= 0 || b >= 0 || c >= 0 || d >= 0 {
		return 1
	}
	return 0
}

func UintGtZero(a uint8, b uint16, c uint32, d uint64) int {
	// arm64: `(CBN?ZW)`, `(CBN?Z[^W])`, -`(CMPW|CMP|BLS|BHI)`
	if a > 0 || b > 0 || c > 0 || d > 0 {
		return 1
	}
	return 0
}

func UintLeqZero(a uint8, b uint16, c uint32, d uint64) int {
	// arm64: `(CBN?ZW)`, `(CBN?Z[^W])`, -`(CMPW|CMP|BHI|BLS)`
	if a <= 0 || b <= 0 || c <= 0 || d <= 0 {
		return 1
	}
	return 0
}

func UintLtOne(a uint8, b uint16, c uint32, d uint64) int {
	// arm64: `(CBN?ZW)`, `(CBN?Z[^W])`, -`(CMPW|CMP|BHS|BLO)`
	if a < 1 || b < 1 || c < 1 || d < 1 {
		return 1
	}
	return 0
}

func UintGeqOne(a uint8, b uint16, c uint32, d uint64) int {
	// arm64: `(CBN?ZW)`, `(CBN?Z[^W])`, -`(CMPW|CMP|BLO|BHS)`
	if a >= 1 || b >= 1 || c >= 1 || d >= 1 {
		return 1
	}
	return 0
}

func CmpToZeroU_ex1(a uint8, b uint16, c uint32, d uint64) int {
	// wasm:"I64Eqz"-"I64LtU"
	if 0 < a {
		return 1
	}
	// wasm:"I64Eqz"-"I64LtU"
	if 0 < b {
		return 1
	}
	// wasm:"I64Eqz"-"I64LtU"
	if 0 < c {
		return 1
	}
	// wasm:"I64Eqz"-"I64LtU"
	if 0 < d {
		return 1
	}
	return 0
}

func CmpToZeroU_ex2(a uint8, b uint16, c uint32, d uint64) int {
	// wasm:"I64Eqz"-"I64LeU"
	if a <= 0 {
		return 1
	}
	// wasm:"I64Eqz"-"I64LeU"
	if b <= 0 {
		return 1
	}
	// wasm:"I64Eqz"-"I64LeU"
	if c <= 0 {
		return 1
	}
	// wasm:"I64Eqz"-"I64LeU"
	if d <= 0 {
		return 1
	}
	return 0
}

func CmpToOneU_ex1(a uint8, b uint16, c uint32, d uint64) int {
	// wasm:"I64Eqz"-"I64LtU"
	if a < 1 {
		return 1
	}
	// wasm:"I64Eqz"-"I64LtU"
	if b < 1 {
		return 1
	}
	// wasm:"I64Eqz"-"I64LtU"
	if c < 1 {
		return 1
	}
	// wasm:"I64Eqz"-"I64LtU"
	if d < 1 {
		return 1
	}
	return 0
}

func CmpToOneU_ex2(a uint8, b uint16, c uint32, d uint64) int {
	// wasm:"I64Eqz"-"I64LeU"
	if 1 <= a {
		return 1
	}
	// wasm:"I64Eqz"-"I64LeU"
	if 1 <= b {
		return 1
	}
	// wasm:"I64Eqz"-"I64LeU"
	if 1 <= c {
		return 1
	}
	// wasm:"I64Eqz"-"I64LeU"
	if 1 <= d {
		return 1
	}
	return 0
}

// Check that small memequals are replaced with eq instructions

func equalConstString1() bool {
	a := string("A")
	b := string("Z")
	// amd64:-".*memequal"
	// arm64:-".*memequal"
	// ppc64:-".*memequal"
	// ppc64le:-".*memequal"
	return a == b
}

func equalVarString1(a string) bool {
	b := string("Z")
	// amd64:-".*memequal"
	// arm64:-".*memequal"
	// ppc64:-".*memequal"
	// ppc64le:-".*memequal"
	return a[:1] == b
}

func equalConstString2() bool {
	a := string("AA")
	b := string("ZZ")
	// amd64:-".*memequal"
	// arm64:-".*memequal"
	// ppc64:-".*memequal"
	// ppc64le:-".*memequal"
	return a == b
}

func equalVarString2(a string) bool {
	b := string("ZZ")
	// amd64:-".*memequal"
	// arm64:-".*memequal"
	// ppc64:-".*memequal"
	// ppc64le:-".*memequal"
	return a[:2] == b
}

func equalConstString4() bool {
	a := string("AAAA")
	b := string("ZZZZ")
	// amd64:-".*memequal"
	// arm64:-".*memequal"
	// ppc64:-".*memequal"
	// ppc64le:-".*memequal"
	return a == b
}

func equalVarString4(a string) bool {
	b := string("ZZZZ")
	// amd64:-".*memequal"
	// arm64:-".*memequal"
	// ppc64:-".*memequal"
	// ppc64le:-".*memequal"
	return a[:4] == b
}

func equalConstString8() bool {
	a := string("AAAAAAAA")
	b := string("ZZZZZZZZ")
	// amd64:-".*memequal"
	// arm64:-".*memequal"
	// ppc64:-".*memequal"
	// ppc64le:-".*memequal"
	return a == b
}

func equalVarString8(a string) bool {
	b := string("ZZZZZZZZ")
	// amd64:-".*memequal"
	// arm64:-".*memequal"
	// ppc64:-".*memequal"
	// ppc64le:-".*memequal"
	return a[:8] == b
}

相关信息

go 源码目录

相关文章

go addrcalc 源码

go alloc 源码

go arithmetic 源码

go bitfield 源码

go bits 源码

go bmi 源码

go bool 源码

go clobberdead 源码

go clobberdeadreg 源码

go compare_and_branch 源码

0  赞