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d292f77e95
Rewrite x<<1+c into x+x+c, which can be expressed as a single LEAQ/LEAL. Bit of a special case, but the single-instruction LEA is both shorter and faster than SHL then ADD. Triggers 293 times during make.bash. Change-Id: I3f09c8e9a8f3859d1eeed336f095fc3ada79c2c1 Reviewed-on: https://go-review.googlesource.com/108938 Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Keith Randall <khr@golang.org>
181 lines
3.7 KiB
Go
181 lines
3.7 KiB
Go
// asmcheck
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// Copyright 2018 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package codegen
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// This file contains codegen tests related to arithmetic
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// simplifications and optimizations on integer types.
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// For codegen tests on float types, see floats.go.
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// ----------------- //
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// Subtraction //
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// ----------------- //
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func SubMem(arr []int) int {
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// 386:"SUBL\t4"
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// amd64:"SUBQ\t8"
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return arr[0] - arr[1]
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}
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// -------------------- //
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// Multiplication //
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// -------------------- //
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func Pow2Muls(n1, n2 int) (int, int) {
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// amd64:"SHLQ\t[$]5",-"IMULQ"
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// 386:"SHLL\t[$]5",-"IMULL"
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// arm:"SLL\t[$]5",-"MUL"
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// arm64:"LSL\t[$]5",-"MUL"
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a := n1 * 32
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// amd64:"SHLQ\t[$]6",-"IMULQ"
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// 386:"SHLL\t[$]6",-"IMULL"
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// arm:"SLL\t[$]6",-"MUL"
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// arm64:"LSL\t[$]6",-"MUL"
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b := -64 * n2
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return a, b
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}
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func Mul_96(n int) int {
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// amd64:`SHLQ\t[$]5`,`LEAQ\t\(.*\)\(.*\*2\),`
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return n * 96
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}
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// Multiplications merging tests
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func MergeMuls1(n int) int {
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// amd64:"IMUL3Q\t[$]46"
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// 386:"IMUL3L\t[$]46"
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return 15*n + 31*n // 46n
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}
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func MergeMuls2(n int) int {
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// amd64:"IMUL3Q\t[$]23","ADDQ\t[$]29"
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// 386:"IMUL3L\t[$]23","ADDL\t[$]29"
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return 5*n + 7*(n+1) + 11*(n+2) // 23n + 29
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}
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func MergeMuls3(a, n int) int {
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// amd64:"ADDQ\t[$]19",-"IMULQ\t[$]19"
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// 386:"ADDL\t[$]19",-"IMULL\t[$]19"
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return a*n + 19*n // (a+19)n
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}
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func MergeMuls4(n int) int {
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// amd64:"IMUL3Q\t[$]14"
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// 386:"IMUL3L\t[$]14"
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return 23*n - 9*n // 14n
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}
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func MergeMuls5(a, n int) int {
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// amd64:"ADDQ\t[$]-19",-"IMULQ\t[$]19"
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// 386:"ADDL\t[$]-19",-"IMULL\t[$]19"
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return a*n - 19*n // (a-19)n
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}
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// -------------- //
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// Division //
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// -------------- //
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func Pow2Divs(n1 uint, n2 int) (uint, int) {
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// 386:"SHRL\t[$]5",-"DIVL"
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// amd64:"SHRQ\t[$]5",-"DIVQ"
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// arm:"SRL\t[$]5",-".*udiv"
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// arm64:"LSR\t[$]5",-"UDIV"
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a := n1 / 32 // unsigned
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// amd64:"SARQ\t[$]6",-"IDIVQ"
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// 386:"SARL\t[$]6",-"IDIVL"
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// arm:"SRA\t[$]6",-".*udiv"
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// arm64:"ASR\t[$]6",-"SDIV"
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b := n2 / 64 // signed
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return a, b
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}
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// Check that constant divisions get turned into MULs
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func ConstDivs(n1 uint, n2 int) (uint, int) {
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// amd64:"MOVQ\t[$]-1085102592571150095","MULQ",-"DIVQ"
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a := n1 / 17 // unsigned
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// amd64:"MOVQ\t[$]-1085102592571150095","IMULQ",-"IDIVQ"
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b := n2 / 17 // signed
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return a, b
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}
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func Pow2Mods(n1 uint, n2 int) (uint, int) {
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// 386:"ANDL\t[$]31",-"DIVL"
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// amd64:"ANDQ\t[$]31",-"DIVQ"
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// arm:"AND\t[$]31",-".*udiv"
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// arm64:"AND\t[$]31",-"UDIV"
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a := n1 % 32 // unsigned
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// 386:-"IDIVL"
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// amd64:-"IDIVQ"
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// arm:-".*udiv"
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// arm64:-"REM"
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b := n2 % 64 // signed
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return a, b
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}
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// Check that constant modulo divs get turned into MULs
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func ConstMods(n1 uint, n2 int) (uint, int) {
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// amd64:"MOVQ\t[$]-1085102592571150095","MULQ",-"DIVQ"
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a := n1 % 17 // unsigned
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// amd64:"MOVQ\t[$]-1085102592571150095","IMULQ",-"IDIVQ"
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b := n2 % 17 // signed
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return a, b
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}
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// Check that len() and cap() calls divided by powers of two are
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// optimized into shifts and ands
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func LenDiv1(a []int) int {
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// 386:"SHRL\t[$]10"
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// amd64:"SHRQ\t[$]10"
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return len(a) / 1024
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}
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func LenDiv2(s string) int {
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// 386:"SHRL\t[$]11"
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// amd64:"SHRQ\t[$]11"
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return len(s) / (4097 >> 1)
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}
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func LenMod1(a []int) int {
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// 386:"ANDL\t[$]1023"
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// amd64:"ANDQ\t[$]1023"
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return len(a) % 1024
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}
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func LenMod2(s string) int {
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// 386:"ANDL\t[$]2047"
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// amd64:"ANDQ\t[$]2047"
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return len(s) % (4097 >> 1)
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}
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func CapDiv(a []int) int {
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// 386:"SHRL\t[$]12"
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// amd64:"SHRQ\t[$]12"
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return cap(a) / ((1 << 11) + 2048)
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}
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func CapMod(a []int) int {
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// 386:"ANDL\t[$]4095"
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// amd64:"ANDQ\t[$]4095"
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return cap(a) % ((1 << 11) + 2048)
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}
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func AddMul(x int) int {
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// amd64:"LEAQ\t1"
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return 2*x + 1
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}
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