1
0
mirror of https://github.com/golang/go synced 2024-11-27 01:01:21 -07:00
go/test/codegen/comparisons.go
khr@golang.org 1a0b86375f cmd/compile: remove redundant calls to cmpstring
The results of cmpstring are reuseable if the second call has the
same arguments and memory.

Note that this gets rid of cmpstring, but we still generate a
redundant </<= test and branch afterwards, because the compiler
doesn't know that cmpstring only ever returns -1,0,1.

Update #61725

Change-Id: I93a0d1ccca50d90b1e1a888240ffb75a3b10b59b
Reviewed-on: https://go-review.googlesource.com/c/go/+/578835
Reviewed-by: David Chase <drchase@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
2024-04-19 16:31:02 +00:00

828 lines
15 KiB
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 (
"cmp"
"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]`,`MOVD\t[$]`,`CMPW\tR`
// 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`
// ppc64x:-`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))
}
// Check that some structs generate 2/4/8 byte compares.
type T1 struct {
a [8]byte
}
func CompareStruct1(s1, s2 T1) bool {
// amd64:`CMPQ\tcommand-line-arguments[.+_a-z0-9]+\(SP\), [A-Z]`
// amd64:-`CALL`
return s1 == s2
}
type T2 struct {
a [16]byte
}
func CompareStruct2(s1, s2 T2) bool {
// amd64:`CMPQ\tcommand-line-arguments[.+_a-z0-9]+\(SP\), [A-Z]`
// amd64:-`CALL`
return s1 == s2
}
// Assert that a memequal call is still generated when
// inlining would increase binary size too much.
type T3 struct {
a [24]byte
}
func CompareStruct3(s1, s2 T3) bool {
// amd64:-`CMPQ\tcommand-line-arguments[.+_a-z0-9]+\(SP\), [A-Z]`
// amd64:`CALL`
return s1 == s2
}
type T4 struct {
a [32]byte
}
func CompareStruct4(s1, s2 T4) bool {
// amd64:-`CMPQ\tcommand-line-arguments[.+_a-z0-9]+\(SP\), [A-Z]`
// amd64:`CALL`
return s1 == s2
}
// -------------- //
// 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
// arm64:`TST\sR[0-9],\sR[0-9]+`
c9 := e&(-19) < 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 c9 {
return 11
} 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 {
// ppc64x:"ANDCC",-"CMPW"
// wasm:"I64Eqz",-"I32Eqz",-"I64ExtendI32U",-"I32WrapI64"
if a&63 == 0 {
return 1
}
// ppc64x:"ANDCC",-"CMP"
// wasm:"I64Eqz",-"I32Eqz",-"I64ExtendI32U",-"I32WrapI64"
if d&255 == 0 {
return 1
}
// ppc64x:"ANDCC",-"CMP"
// wasm:"I64Eqz",-"I32Eqz",-"I64ExtendI32U",-"I32WrapI64"
if d&e == 0 {
return 1
}
// ppc64x:"ORCC",-"CMP"
// wasm:"I64Eqz",-"I32Eqz",-"I64ExtendI32U",-"I32WrapI64"
if d|e == 0 {
return 1
}
// ppc64x:"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:`SUB`,`TBZ`
if a-11 >= 0 {
return 4
}
// arm64:`SUB`,`CMP`,`BGT`
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:`SUB`,`TBNZ`
// 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"
// ppc64x:-".*memequal"
return a == b
}
func equalVarString1(a string) bool {
b := string("Z")
// amd64:-".*memequal"
// arm64:-".*memequal"
// ppc64x:-".*memequal"
return a[:1] == b
}
func equalConstString2() bool {
a := string("AA")
b := string("ZZ")
// amd64:-".*memequal"
// arm64:-".*memequal"
// ppc64x:-".*memequal"
return a == b
}
func equalVarString2(a string) bool {
b := string("ZZ")
// amd64:-".*memequal"
// arm64:-".*memequal"
// ppc64x:-".*memequal"
return a[:2] == b
}
func equalConstString4() bool {
a := string("AAAA")
b := string("ZZZZ")
// amd64:-".*memequal"
// arm64:-".*memequal"
// ppc64x:-".*memequal"
return a == b
}
func equalVarString4(a string) bool {
b := string("ZZZZ")
// amd64:-".*memequal"
// arm64:-".*memequal"
// ppc64x:-".*memequal"
return a[:4] == b
}
func equalConstString8() bool {
a := string("AAAAAAAA")
b := string("ZZZZZZZZ")
// amd64:-".*memequal"
// arm64:-".*memequal"
// ppc64x:-".*memequal"
return a == b
}
func equalVarString8(a string) bool {
b := string("ZZZZZZZZ")
// amd64:-".*memequal"
// arm64:-".*memequal"
// ppc64x:-".*memequal"
return a[:8] == b
}
func cmpToCmn(a, b, c, d int) int {
var c1, c2, c3, c4, c5, c6, c7, c8, c9, c10, c11 int
// arm64:`CMN`,-`CMP`
if a < -8 {
c1 = 1
}
// arm64:`CMN`,-`CMP`
if a+1 == 0 {
c2 = 1
}
// arm64:`CMN`,-`CMP`
if a+3 != 0 {
c3 = 1
}
// arm64:`CMN`,-`CMP`
if a+b == 0 {
c4 = 1
}
// arm64:`CMN`,-`CMP`
if b+c != 0 {
c5 = 1
}
// arm64:`CMN`,-`CMP`
if a == -c {
c6 = 1
}
// arm64:`CMN`,-`CMP`
if b != -d {
c7 = 1
}
// arm64:`CMN`,-`CMP`
if a*b+c == 0 {
c8 = 1
}
// arm64:`CMN`,-`CMP`
if a*c+b != 0 {
c9 = 1
}
// arm64:`CMP`,-`CMN`
if b*c-a == 0 {
c10 = 1
}
// arm64:`CMP`,-`CMN`
if a*d-b != 0 {
c11 = 1
}
return c1 + c2 + c3 + c4 + c5 + c6 + c7 + c8 + c9 + c10 + c11
}
func cmpToCmnLessThan(a, b, c, d int) int {
var c1, c2, c3, c4 int
// arm64:`CMN`,`CSET\tMI`,-`CMP`
if a+1 < 0 {
c1 = 1
}
// arm64:`CMN`,`CSET\tMI`,-`CMP`
if a+b < 0 {
c2 = 1
}
// arm64:`CMN`,`CSET\tMI`,-`CMP`
if a*b+c < 0 {
c3 = 1
}
// arm64:`CMP`,`CSET\tMI`,-`CMN`
if a-b*c < 0 {
c4 = 1
}
return c1 + c2 + c3 + c4
}
func cmpToCmnGreaterThanEqual(a, b, c, d int) int {
var c1, c2, c3, c4 int
// arm64:`CMN`,`CSET\tPL`,-`CMP`
if a+1 >= 0 {
c1 = 1
}
// arm64:`CMN`,`CSET\tPL`,-`CMP`
if a+b >= 0 {
c2 = 1
}
// arm64:`CMN`,`CSET\tPL`,-`CMP`
if a*b+c >= 0 {
c3 = 1
}
// arm64:`CMP`,`CSET\tPL`,-`CMN`
if a-b*c >= 0 {
c4 = 1
}
return c1 + c2 + c3 + c4
}
func cmp1(val string) bool {
var z string
// amd64:-".*memequal"
return z == val
}
func cmp2(val string) bool {
var z string
// amd64:-".*memequal"
return val == z
}
func cmp3(val string) bool {
z := "food"
// amd64:-".*memequal"
return z == val
}
func cmp4(val string) bool {
z := "food"
// amd64:-".*memequal"
return val == z
}
func cmp5[T comparable](val T) bool {
var z T
// amd64:-".*memequal"
return z == val
}
func cmp6[T comparable](val T) bool {
var z T
// amd64:-".*memequal"
return val == z
}
func cmp7() {
cmp5[string]("") // force instantiation
cmp6[string]("") // force instantiation
}
type Point struct {
X, Y int
}
// invertLessThanNoov checks (LessThanNoov (InvertFlags x)) is lowered as
// CMP, CSET, CSEL instruction sequence. InvertFlags are only generated under
// certain conditions, see canonLessThan, so if the code below does not
// generate an InvertFlags OP, this check may fail.
func invertLessThanNoov(p1, p2, p3 Point) bool {
// arm64:`CMP`,`CSET`,`CSEL`
return (p1.X-p3.X)*(p2.Y-p3.Y)-(p2.X-p3.X)*(p1.Y-p3.Y) < 0
}
func cmpstring1(x, y string) int {
// amd64:".*cmpstring"
if x < y {
return -1
}
// amd64:-".*cmpstring"
if x > y {
return +1
}
return 0
}
func cmpstring2(x, y string) int {
// We want to fail if there are two calls to cmpstring.
// They will both have the same line number, so a test
// like in cmpstring1 will not work. Instead, we
// look for spill/restore instructions, which only
// need to exist if there are 2 calls.
//amd64:-`MOVQ\t.*\(SP\)`
return cmp.Compare(x, y)
}