go/test/codegen/arithmetic.go
Michael Munday 6e876f1985 cmd/compile: clean up and optimize s390x multiplication rules
Some of the existing optimizations aren't triggered because they
are handled by the generic rules so this CL removes them. Also
some constraints were copied without much thought from the amd64
rules and they don't make sense on s390x, so we remove those
constraints.

Finally, add a 'multiply by the sum of two powers of two'
optimization. This makes sense on s390x as shifts are low latency
and can also sometimes be optimized further (especially if we add
support for RISBG instructions).

name                   old time/op  new time/op  delta
IntMulByConst/3-8      1.70ns ±11%  1.10ns ± 5%  -35.26%  (p=0.000 n=10+10)
IntMulByConst/5-8      1.64ns ± 7%  1.10ns ± 4%  -32.94%  (p=0.000 n=10+9)
IntMulByConst/12-8     1.65ns ± 6%  1.20ns ± 4%  -27.16%  (p=0.000 n=10+9)
IntMulByConst/120-8    1.66ns ± 4%  1.22ns ±13%  -26.43%  (p=0.000 n=10+10)
IntMulByConst/-120-8   1.65ns ± 7%  1.19ns ± 4%  -28.06%  (p=0.000 n=9+10)
IntMulByConst/65537-8  0.86ns ± 9%  1.12ns ±12%  +30.41%  (p=0.000 n=10+10)
IntMulByConst/65538-8  1.65ns ± 5%  1.23ns ± 5%  -25.11%  (p=0.000 n=10+10)

Change-Id: Ib196e6bff1e97febfd266134d0a2b2a62897989f
Reviewed-on: https://go-review.googlesource.com/c/go/+/248937
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2020-08-18 15:39:44 +00:00

471 lines
11 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
// This file contains codegen tests related to arithmetic
// simplifications and optimizations on integer types.
// For codegen tests on float types, see floats.go.
// ----------------- //
// Subtraction //
// ----------------- //
var ef int
func SubMem(arr []int, b, c, d int) int {
// 386:`SUBL\s[A-Z]+,\s8\([A-Z]+\)`
// amd64:`SUBQ\s[A-Z]+,\s16\([A-Z]+\)`
arr[2] -= b
// 386:`SUBL\s[A-Z]+,\s12\([A-Z]+\)`
// amd64:`SUBQ\s[A-Z]+,\s24\([A-Z]+\)`
arr[3] -= b
// 386:`DECL\s16\([A-Z]+\)`
arr[4]--
// 386:`ADDL\s[$]-20,\s20\([A-Z]+\)`
arr[5] -= 20
// 386:`SUBL\s\([A-Z]+\)\([A-Z]+\*4\),\s[A-Z]+`
ef -= arr[b]
// 386:`SUBL\s[A-Z]+,\s\([A-Z]+\)\([A-Z]+\*4\)`
arr[c] -= b
// 386:`ADDL\s[$]-15,\s\([A-Z]+\)\([A-Z]+\*4\)`
arr[d] -= 15
// 386:`DECL\s\([A-Z]+\)\([A-Z]+\*4\)`
arr[b]--
// amd64:`DECQ\s64\([A-Z]+\)`
arr[8]--
// 386:"SUBL\t4"
// amd64:"SUBQ\t8"
return arr[0] - arr[1]
}
// -------------------- //
// Multiplication //
// -------------------- //
func Pow2Muls(n1, n2 int) (int, int) {
// amd64:"SHLQ\t[$]5",-"IMULQ"
// 386:"SHLL\t[$]5",-"IMULL"
// arm:"SLL\t[$]5",-"MUL"
// arm64:"LSL\t[$]5",-"MUL"
// ppc64:"SLD\t[$]5",-"MUL"
// ppc64le:"SLD\t[$]5",-"MUL"
a := n1 * 32
// amd64:"SHLQ\t[$]6",-"IMULQ"
// 386:"SHLL\t[$]6",-"IMULL"
// arm:"SLL\t[$]6",-"MUL"
// arm64:`NEG\sR[0-9]+<<6,\sR[0-9]+`,-`LSL`,-`MUL`
// ppc64:"SLD\t[$]6","NEG\\sR[0-9]+,\\sR[0-9]+",-"MUL"
// ppc64le:"SLD\t[$]6","NEG\\sR[0-9]+,\\sR[0-9]+",-"MUL"
b := -64 * n2
return a, b
}
func Mul_96(n int) int {
// amd64:`SHLQ\t[$]5`,`LEAQ\t\(.*\)\(.*\*2\),`,-`IMULQ`
// 386:`SHLL\t[$]5`,`LEAL\t\(.*\)\(.*\*2\),`,-`IMULL`
// arm64:`LSL\t[$]5`,`ADD\sR[0-9]+<<1,\sR[0-9]+`,-`MUL`
// arm:`SLL\t[$]5`,`ADD\sR[0-9]+<<1,\sR[0-9]+`,-`MUL`
// s390x:`SLD\t[$]5`,`SLD\t[$]6`,-`MULLD`
return n * 96
}
func Mul_n120(n int) int {
// s390x:`SLD\t[$]3`,`SLD\t[$]7`,-`MULLD`
return n * -120
}
func MulMemSrc(a []uint32, b []float32) {
// 386:`IMULL\s4\([A-Z]+\),\s[A-Z]+`
a[0] *= a[1]
// 386/sse2:`MULSS\s4\([A-Z]+\),\sX[0-9]+`
// amd64:`MULSS\s4\([A-Z]+\),\sX[0-9]+`
b[0] *= b[1]
}
// Multiplications merging tests
func MergeMuls1(n int) int {
// amd64:"IMUL3Q\t[$]46"
// 386:"IMUL3L\t[$]46"
return 15*n + 31*n // 46n
}
func MergeMuls2(n int) int {
// amd64:"IMUL3Q\t[$]23","ADDQ\t[$]29"
// 386:"IMUL3L\t[$]23","ADDL\t[$]29"
return 5*n + 7*(n+1) + 11*(n+2) // 23n + 29
}
func MergeMuls3(a, n int) int {
// amd64:"ADDQ\t[$]19",-"IMULQ\t[$]19"
// 386:"ADDL\t[$]19",-"IMULL\t[$]19"
return a*n + 19*n // (a+19)n
}
func MergeMuls4(n int) int {
// amd64:"IMUL3Q\t[$]14"
// 386:"IMUL3L\t[$]14"
return 23*n - 9*n // 14n
}
func MergeMuls5(a, n int) int {
// amd64:"ADDQ\t[$]-19",-"IMULQ\t[$]19"
// 386:"ADDL\t[$]-19",-"IMULL\t[$]19"
return a*n - 19*n // (a-19)n
}
// -------------- //
// Division //
// -------------- //
func DivMemSrc(a []float64) {
// 386/sse2:`DIVSD\s8\([A-Z]+\),\sX[0-9]+`
// amd64:`DIVSD\s8\([A-Z]+\),\sX[0-9]+`
a[0] /= a[1]
}
func Pow2Divs(n1 uint, n2 int) (uint, int) {
// 386:"SHRL\t[$]5",-"DIVL"
// amd64:"SHRQ\t[$]5",-"DIVQ"
// arm:"SRL\t[$]5",-".*udiv"
// arm64:"LSR\t[$]5",-"UDIV"
// ppc64:"SRD"
// ppc64le:"SRD"
a := n1 / 32 // unsigned
// amd64:"SARQ\t[$]6",-"IDIVQ"
// 386:"SARL\t[$]6",-"IDIVL"
// arm:"SRA\t[$]6",-".*udiv"
// arm64:"ASR\t[$]6",-"SDIV"
// ppc64:"SRAD"
// ppc64le:"SRAD"
b := n2 / 64 // signed
return a, b
}
// Check that constant divisions get turned into MULs
func ConstDivs(n1 uint, n2 int) (uint, int) {
// amd64:"MOVQ\t[$]-1085102592571150095","MULQ",-"DIVQ"
// 386:"MOVL\t[$]-252645135","MULL",-"DIVL"
// arm64:`MOVD`,`UMULH`,-`DIV`
// arm:`MOVW`,`MUL`,-`.*udiv`
a := n1 / 17 // unsigned
// amd64:"MOVQ\t[$]-1085102592571150095","IMULQ",-"IDIVQ"
// 386:"MOVL\t[$]-252645135","IMULL",-"IDIVL"
// arm64:`MOVD`,`SMULH`,-`DIV`
// arm:`MOVW`,`MUL`,-`.*udiv`
b := n2 / 17 // signed
return a, b
}
func FloatDivs(a []float32) float32 {
// amd64:`DIVSS\s8\([A-Z]+\),\sX[0-9]+`
// 386/sse2:`DIVSS\s8\([A-Z]+\),\sX[0-9]+`
return a[1] / a[2]
}
func Pow2Mods(n1 uint, n2 int) (uint, int) {
// 386:"ANDL\t[$]31",-"DIVL"
// amd64:"ANDQ\t[$]31",-"DIVQ"
// arm:"AND\t[$]31",-".*udiv"
// arm64:"AND\t[$]31",-"UDIV"
// ppc64:"ANDCC\t[$]31"
// ppc64le:"ANDCC\t[$]31"
a := n1 % 32 // unsigned
// 386:"SHRL",-"IDIVL"
// amd64:"SHRQ",-"IDIVQ"
// arm:"SRA",-".*udiv"
// arm64:"ASR",-"REM"
// ppc64:"SRAD"
// ppc64le:"SRAD"
b := n2 % 64 // signed
return a, b
}
// Check that signed divisibility checks get converted to AND on low bits
func Pow2DivisibleSigned(n1, n2 int) (bool, bool) {
// 386:"TESTL\t[$]63",-"DIVL",-"SHRL"
// amd64:"TESTQ\t[$]63",-"DIVQ",-"SHRQ"
// arm:"AND\t[$]63",-".*udiv",-"SRA"
// arm64:"AND\t[$]63",-"UDIV",-"ASR"
// ppc64:"ANDCC\t[$]63",-"SRAD"
// ppc64le:"ANDCC\t[$]63",-"SRAD"
a := n1%64 == 0 // signed divisible
// 386:"TESTL\t[$]63",-"DIVL",-"SHRL"
// amd64:"TESTQ\t[$]63",-"DIVQ",-"SHRQ"
// arm:"AND\t[$]63",-".*udiv",-"SRA"
// arm64:"AND\t[$]63",-"UDIV",-"ASR"
// ppc64:"ANDCC\t[$]63",-"SRAD"
// ppc64le:"ANDCC\t[$]63",-"SRAD"
b := n2%64 != 0 // signed indivisible
return a, b
}
// Check that constant modulo divs get turned into MULs
func ConstMods(n1 uint, n2 int) (uint, int) {
// amd64:"MOVQ\t[$]-1085102592571150095","MULQ",-"DIVQ"
// 386:"MOVL\t[$]-252645135","MULL",-"DIVL"
// arm64:`MOVD`,`UMULH`,-`DIV`
// arm:`MOVW`,`MUL`,-`.*udiv`
a := n1 % 17 // unsigned
// amd64:"MOVQ\t[$]-1085102592571150095","IMULQ",-"IDIVQ"
// 386:"MOVL\t[$]-252645135","IMULL",-"IDIVL"
// arm64:`MOVD`,`SMULH`,-`DIV`
// arm:`MOVW`,`MUL`,-`.*udiv`
b := n2 % 17 // signed
return a, b
}
// Check that divisibility checks x%c==0 are converted to MULs and rotates
func Divisible(n1 uint, n2 int) (bool, bool, bool, bool) {
// amd64:"MOVQ\t[$]-6148914691236517205","IMULQ","ROLQ\t[$]63",-"DIVQ"
// 386:"IMUL3L\t[$]-1431655765","ROLL\t[$]31",-"DIVQ"
// arm64:"MOVD\t[$]-6148914691236517205","MUL","ROR",-"DIV"
// arm:"MUL","CMP\t[$]715827882",-".*udiv"
// ppc64:"MULLD","ROTL\t[$]63"
// ppc64le:"MULLD","ROTL\t[$]63"
evenU := n1%6 == 0
// amd64:"MOVQ\t[$]-8737931403336103397","IMULQ",-"ROLQ",-"DIVQ"
// 386:"IMUL3L\t[$]678152731",-"ROLL",-"DIVQ"
// arm64:"MOVD\t[$]-8737931403336103397","MUL",-"ROR",-"DIV"
// arm:"MUL","CMP\t[$]226050910",-".*udiv"
// ppc64:"MULLD",-"ROTL"
// ppc64le:"MULLD",-"ROTL"
oddU := n1%19 == 0
// amd64:"IMULQ","ADD","ROLQ\t[$]63",-"DIVQ"
// 386:"IMUL3L\t[$]-1431655765","ADDL\t[$]715827882","ROLL\t[$]31",-"DIVQ"
// arm64:"MUL","ADD\t[$]3074457345618258602","ROR",-"DIV"
// arm:"MUL","ADD\t[$]715827882",-".*udiv"
// ppc64:"MULLD","ADD","ROTL\t[$]63"
// ppc64le:"MULLD","ADD","ROTL\t[$]63"
evenS := n2%6 == 0
// amd64:"IMULQ","ADD",-"ROLQ",-"DIVQ"
// 386:"IMUL3L\t[$]678152731","ADDL\t[$]113025455",-"ROLL",-"DIVQ"
// arm64:"MUL","ADD\t[$]485440633518672410",-"ROR",-"DIV"
// arm:"MUL","ADD\t[$]113025455",-".*udiv"
// ppc64:"MULLD","ADD",-"ROTL"
// ppc64le:"MULLD","ADD",-"ROTL"
oddS := n2%19 == 0
return evenU, oddU, evenS, oddS
}
// Check that fix-up code is not generated for divisions where it has been proven that
// that the divisor is not -1 or that the dividend is > MinIntNN.
func NoFix64A(divr int64) (int64, int64) {
var d int64 = 42
var e int64 = 84
if divr > 5 {
d /= divr // amd64:-"JMP"
e %= divr // amd64:-"JMP"
}
return d, e
}
func NoFix64B(divd int64) (int64, int64) {
var d int64
var e int64
var divr int64 = -1
if divd > -9223372036854775808 {
d = divd / divr // amd64:-"JMP"
e = divd % divr // amd64:-"JMP"
}
return d, e
}
func NoFix32A(divr int32) (int32, int32) {
var d int32 = 42
var e int32 = 84
if divr > 5 {
// amd64:-"JMP"
// 386:-"JMP"
d /= divr
// amd64:-"JMP"
// 386:-"JMP"
e %= divr
}
return d, e
}
func NoFix32B(divd int32) (int32, int32) {
var d int32
var e int32
var divr int32 = -1
if divd > -2147483648 {
// amd64:-"JMP"
// 386:-"JMP"
d = divd / divr
// amd64:-"JMP"
// 386:-"JMP"
e = divd % divr
}
return d, e
}
func NoFix16A(divr int16) (int16, int16) {
var d int16 = 42
var e int16 = 84
if divr > 5 {
// amd64:-"JMP"
// 386:-"JMP"
d /= divr
// amd64:-"JMP"
// 386:-"JMP"
e %= divr
}
return d, e
}
func NoFix16B(divd int16) (int16, int16) {
var d int16
var e int16
var divr int16 = -1
if divd > -32768 {
// amd64:-"JMP"
// 386:-"JMP"
d = divd / divr
// amd64:-"JMP"
// 386:-"JMP"
e = divd % divr
}
return d, e
}
// Check that len() and cap() calls divided by powers of two are
// optimized into shifts and ands
func LenDiv1(a []int) int {
// 386:"SHRL\t[$]10"
// amd64:"SHRQ\t[$]10"
// arm64:"LSR\t[$]10",-"SDIV"
// arm:"SRL\t[$]10",-".*udiv"
// ppc64:"SRD"\t[$]10"
// ppc64le:"SRD"\t[$]10"
return len(a) / 1024
}
func LenDiv2(s string) int {
// 386:"SHRL\t[$]11"
// amd64:"SHRQ\t[$]11"
// arm64:"LSR\t[$]11",-"SDIV"
// arm:"SRL\t[$]11",-".*udiv"
// ppc64:"SRD\t[$]11"
// ppc64le:"SRD\t[$]11"
return len(s) / (4097 >> 1)
}
func LenMod1(a []int) int {
// 386:"ANDL\t[$]1023"
// amd64:"ANDQ\t[$]1023"
// arm64:"AND\t[$]1023",-"SDIV"
// arm/6:"AND",-".*udiv"
// arm/7:"BFC",-".*udiv",-"AND"
// ppc64:"ANDCC\t[$]1023"
// ppc64le:"ANDCC\t[$]1023"
return len(a) % 1024
}
func LenMod2(s string) int {
// 386:"ANDL\t[$]2047"
// amd64:"ANDQ\t[$]2047"
// arm64:"AND\t[$]2047",-"SDIV"
// arm/6:"AND",-".*udiv"
// arm/7:"BFC",-".*udiv",-"AND"
// ppc64:"ANDCC\t[$]2047"
// ppc64le:"ANDCC\t[$]2047"
return len(s) % (4097 >> 1)
}
func CapDiv(a []int) int {
// 386:"SHRL\t[$]12"
// amd64:"SHRQ\t[$]12"
// arm64:"LSR\t[$]12",-"SDIV"
// arm:"SRL\t[$]12",-".*udiv"
// ppc64:"SRD\t[$]12"
// ppc64le:"SRD\t[$]12"
return cap(a) / ((1 << 11) + 2048)
}
func CapMod(a []int) int {
// 386:"ANDL\t[$]4095"
// amd64:"ANDQ\t[$]4095"
// arm64:"AND\t[$]4095",-"SDIV"
// arm/6:"AND",-".*udiv"
// arm/7:"BFC",-".*udiv",-"AND"
// ppc64:"ANDCC\t[$]4095"
// ppc64le:"ANDCC\t[$]4095"
return cap(a) % ((1 << 11) + 2048)
}
func AddMul(x int) int {
// amd64:"LEAQ\t1"
return 2*x + 1
}
func MULA(a, b, c uint32) (uint32, uint32, uint32) {
// arm:`MULA`,-`MUL\s`
// arm64:`MADDW`,-`MULW`
r0 := a*b + c
// arm:`MULA`,-`MUL\s`
// arm64:`MADDW`,-`MULW`
r1 := c*79 + a
// arm:`ADD`,-`MULA`,-`MUL\s`
// arm64:`ADD`,-`MADD`,-`MULW`
r2 := b*64 + c
return r0, r1, r2
}
func MULS(a, b, c uint32) (uint32, uint32, uint32) {
// arm/7:`MULS`,-`MUL\s`
// arm/6:`SUB`,`MUL\s`,-`MULS`
// arm64:`MSUBW`,-`MULW`
r0 := c - a*b
// arm/7:`MULS`,-`MUL\s`
// arm/6:`SUB`,`MUL\s`,-`MULS`
// arm64:`MSUBW`,-`MULW`
r1 := a - c*79
// arm/7:`SUB`,-`MULS`,-`MUL\s`
// arm64:`SUB`,-`MSUBW`,-`MULW`
r2 := c - b*64
return r0, r1, r2
}
func addSpecial(a, b, c uint32) (uint32, uint32, uint32) {
// amd64:`INCL`
a++
// amd64:`DECL`
b--
// amd64:`SUBL.*-128`
c += 128
return a, b, c
}
// Divide -> shift rules usually require fixup for negative inputs.
// If the input is non-negative, make sure the fixup is eliminated.
func divInt(v int64) int64 {
if v < 0 {
return 0
}
// amd64:-`.*SARQ.*63,`, -".*SHRQ", ".*SARQ.*[$]9,"
return v / 512
}