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https://github.com/golang/go
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4e2b0dda8c
This CL eliminates unnecessary type conversion operations: OpZeroExt16to64 and OpZeroExt8to64.
If the input argrument is a nonzero value, then ORconst operation can also be eliminated.
Benchmarks:
name old time/op new time/op delta
TrailingZeros-8 2.75ns ± 0% 2.75ns ± 0% ~ (all equal)
TrailingZeros8-8 3.49ns ± 1% 2.93ns ± 0% -16.00% (p=0.000 n=10+10)
TrailingZeros16-8 3.49ns ± 1% 2.93ns ± 0% -16.05% (p=0.000 n=9+10)
TrailingZeros32-8 2.67ns ± 1% 2.68ns ± 1% ~ (p=0.468 n=10+10)
TrailingZeros64-8 2.67ns ± 1% 2.65ns ± 0% -0.62% (p=0.022 n=10+9)
code:
func f16(x uint) { z = bits.TrailingZeros16(uint16(x)) }
Before:
"".f16 STEXT size=48 args=0x8 locals=0x0 leaf
0x0000 00000 (test.go:7) TEXT "".f16(SB), LEAF|NOFRAME|ABIInternal, $0-8
0x0000 00000 (test.go:7) FUNCDATA ZR, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
0x0000 00000 (test.go:7) FUNCDATA $1, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
0x0000 00000 (test.go:7) FUNCDATA $3, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
0x0000 00000 (test.go:7) PCDATA $2, ZR
0x0000 00000 (test.go:7) PCDATA ZR, ZR
0x0000 00000 (test.go:7) MOVD "".x(FP), R0
0x0004 00004 (test.go:7) MOVHU R0, R0
0x0008 00008 (test.go:7) ORR $65536, R0, R0
0x000c 00012 (test.go:7) RBIT R0, R0
0x0010 00016 (test.go:7) CLZ R0, R0
0x0014 00020 (test.go:7) MOVD R0, "".z(SB)
0x0020 00032 (test.go:7) RET (R30)
This line of code is unnecessary:
0x0004 00004 (test.go:7) MOVHU R0, R0
After:
"".f16 STEXT size=32 args=0x8 locals=0x0 leaf
0x0000 00000 (test.go:7) TEXT "".f16(SB), LEAF|NOFRAME|ABIInternal, $0-8
0x0000 00000 (test.go:7) FUNCDATA ZR, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
0x0000 00000 (test.go:7) FUNCDATA $1, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
0x0000 00000 (test.go:7) FUNCDATA $3, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
0x0000 00000 (test.go:7) PCDATA $2, ZR
0x0000 00000 (test.go:7) PCDATA ZR, ZR
0x0000 00000 (test.go:7) MOVD "".x(FP), R0
0x0004 00004 (test.go:7) ORR $65536, R0, R0
0x0008 00008 (test.go:7) RBITW R0, R0
0x000c 00012 (test.go:7) CLZW R0, R0
0x0010 00016 (test.go:7) MOVD R0, "".z(SB)
0x001c 00028 (test.go:7) RET (R30)
The situation of TrailingZeros8 is similar to TrailingZeros16.
Change-Id: I473bdca06be8460a0be87abbae6fe640017e4c9d
Reviewed-on: https://go-review.googlesource.com/c/go/+/156999
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
498 lines
9.8 KiB
Go
498 lines
9.8 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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import "math/bits"
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// ----------------------- //
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// bits.LeadingZeros //
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// ----------------------- //
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func LeadingZeros(n uint) int {
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// amd64:"BSRQ"
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// s390x:"FLOGR"
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// arm:"CLZ" arm64:"CLZ"
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// mips:"CLZ"
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return bits.LeadingZeros(n)
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}
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func LeadingZeros64(n uint64) int {
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// amd64:"BSRQ"
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// s390x:"FLOGR"
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// arm:"CLZ" arm64:"CLZ"
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// mips:"CLZ"
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return bits.LeadingZeros64(n)
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}
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func LeadingZeros32(n uint32) int {
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// amd64:"BSRQ","LEAQ",-"CMOVQEQ"
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// s390x:"FLOGR"
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// arm:"CLZ" arm64:"CLZW"
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// mips:"CLZ"
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return bits.LeadingZeros32(n)
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}
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func LeadingZeros16(n uint16) int {
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// amd64:"BSRL","LEAL",-"CMOVQEQ"
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// s390x:"FLOGR"
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// arm:"CLZ" arm64:"CLZ"
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// mips:"CLZ"
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return bits.LeadingZeros16(n)
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}
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func LeadingZeros8(n uint8) int {
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// amd64:"BSRL","LEAL",-"CMOVQEQ"
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// s390x:"FLOGR"
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// arm:"CLZ" arm64:"CLZ"
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// mips:"CLZ"
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return bits.LeadingZeros8(n)
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}
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// --------------- //
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// bits.Len* //
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// --------------- //
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func Len(n uint) int {
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// amd64:"BSRQ"
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// s390x:"FLOGR"
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// arm:"CLZ" arm64:"CLZ"
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// mips:"CLZ"
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return bits.Len(n)
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}
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func Len64(n uint64) int {
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// amd64:"BSRQ"
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// s390x:"FLOGR"
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// arm:"CLZ" arm64:"CLZ"
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// mips:"CLZ"
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return bits.Len64(n)
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}
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func Len32(n uint32) int {
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// amd64:"BSRQ","LEAQ",-"CMOVQEQ"
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// s390x:"FLOGR"
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// arm:"CLZ" arm64:"CLZ"
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// mips:"CLZ"
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return bits.Len32(n)
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}
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func Len16(n uint16) int {
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// amd64:"BSRL","LEAL",-"CMOVQEQ"
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// s390x:"FLOGR"
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// arm:"CLZ" arm64:"CLZ"
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// mips:"CLZ"
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return bits.Len16(n)
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}
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func Len8(n uint8) int {
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// amd64:"BSRL","LEAL",-"CMOVQEQ"
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// s390x:"FLOGR"
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// arm:"CLZ" arm64:"CLZ"
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// mips:"CLZ"
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return bits.Len8(n)
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}
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// -------------------- //
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// bits.OnesCount //
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// -------------------- //
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func OnesCount(n uint) int {
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// amd64:"POPCNTQ",".*x86HasPOPCNT"
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// arm64:"VCNT","VUADDLV"
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// s390x:"POPCNT"
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// ppc64:"POPCNTD"
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// ppc64le:"POPCNTD"
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return bits.OnesCount(n)
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}
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func OnesCount64(n uint64) int {
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// amd64:"POPCNTQ",".*x86HasPOPCNT"
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// arm64:"VCNT","VUADDLV"
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// s390x:"POPCNT"
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// ppc64:"POPCNTD"
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// ppc64le:"POPCNTD"
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return bits.OnesCount64(n)
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}
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func OnesCount32(n uint32) int {
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// amd64:"POPCNTL",".*x86HasPOPCNT"
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// arm64:"VCNT","VUADDLV"
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// s390x:"POPCNT"
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// ppc64:"POPCNTW"
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// ppc64le:"POPCNTW"
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return bits.OnesCount32(n)
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}
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func OnesCount16(n uint16) int {
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// amd64:"POPCNTL",".*x86HasPOPCNT"
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// arm64:"VCNT","VUADDLV"
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// s390x:"POPCNT"
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// ppc64:"POPCNTW"
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// ppc64le:"POPCNTW"
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return bits.OnesCount16(n)
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}
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func OnesCount8(n uint8) int {
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// s390x:"POPCNT"
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// ppc64:"POPCNTB"
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// ppc64le:"POPCNTB"
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return bits.OnesCount8(n)
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}
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// ----------------------- //
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// bits.ReverseBytes //
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// ----------------------- //
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func ReverseBytes(n uint) uint {
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// amd64:"BSWAPQ"
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// s390x:"MOVDBR"
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// arm64:"REV"
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return bits.ReverseBytes(n)
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}
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func ReverseBytes64(n uint64) uint64 {
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// amd64:"BSWAPQ"
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// s390x:"MOVDBR"
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// arm64:"REV"
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return bits.ReverseBytes64(n)
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}
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func ReverseBytes32(n uint32) uint32 {
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// amd64:"BSWAPL"
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// s390x:"MOVWBR"
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// arm64:"REVW"
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return bits.ReverseBytes32(n)
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}
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func ReverseBytes16(n uint16) uint16 {
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// amd64:"ROLW"
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// arm64:"REV16W",-"UBFX",-"ORR"
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// arm/5:"SLL","SRL","ORR"
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// arm/6:"REV16"
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// arm/7:"REV16"
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return bits.ReverseBytes16(n)
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}
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// --------------------- //
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// bits.RotateLeft //
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// --------------------- //
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func RotateLeft64(n uint64) uint64 {
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// amd64:"ROLQ"
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// arm64:"ROR"
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// ppc64:"ROTL"
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// ppc64le:"ROTL"
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// s390x:"RLLG"
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return bits.RotateLeft64(n, 37)
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}
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func RotateLeft32(n uint32) uint32 {
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// amd64:"ROLL" 386:"ROLL"
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// arm64:"RORW"
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// ppc64:"ROTLW"
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// ppc64le:"ROTLW"
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// s390x:"RLL"
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return bits.RotateLeft32(n, 9)
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}
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func RotateLeft16(n uint16) uint16 {
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// amd64:"ROLW" 386:"ROLW"
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return bits.RotateLeft16(n, 5)
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}
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func RotateLeft8(n uint8) uint8 {
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// amd64:"ROLB" 386:"ROLB"
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return bits.RotateLeft8(n, 5)
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}
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func RotateLeftVariable(n uint, m int) uint {
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// amd64:"ROLQ"
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// arm64:"ROR"
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// ppc64:"ROTL"
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// ppc64le:"ROTL"
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// s390x:"RLLG"
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return bits.RotateLeft(n, m)
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}
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func RotateLeftVariable64(n uint64, m int) uint64 {
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// amd64:"ROLQ"
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// arm64:"ROR"
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// ppc64:"ROTL"
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// ppc64le:"ROTL"
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// s390x:"RLLG"
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return bits.RotateLeft64(n, m)
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}
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func RotateLeftVariable32(n uint32, m int) uint32 {
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// amd64:"ROLL"
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// arm64:"RORW"
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// ppc64:"ROTLW"
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// ppc64le:"ROTLW"
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// s390x:"RLL"
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return bits.RotateLeft32(n, m)
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}
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// ------------------------ //
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// bits.TrailingZeros //
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// ------------------------ //
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func TrailingZeros(n uint) int {
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// amd64:"BSFQ","MOVL\t\\$64","CMOVQEQ"
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// arm64:"RBIT","CLZ"
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// s390x:"FLOGR"
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// ppc64:"ANDN","POPCNTD"
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// ppc64le:"ANDN","POPCNTD"
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return bits.TrailingZeros(n)
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}
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func TrailingZeros64(n uint64) int {
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// amd64:"BSFQ","MOVL\t\\$64","CMOVQEQ"
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// arm64:"RBIT","CLZ"
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// s390x:"FLOGR"
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// ppc64:"ANDN","POPCNTD"
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// ppc64le:"ANDN","POPCNTD"
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return bits.TrailingZeros64(n)
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}
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func TrailingZeros32(n uint32) int {
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// amd64:"BTSQ\\t\\$32","BSFQ"
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// arm64:"RBITW","CLZW"
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// s390x:"FLOGR","MOVWZ"
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// ppc64:"ANDN","POPCNTW"
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// ppc64le:"ANDN","POPCNTW"
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return bits.TrailingZeros32(n)
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}
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func TrailingZeros16(n uint16) int {
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// amd64:"BSFL","BTSL\\t\\$16"
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// arm64:"ORR\t\\$65536","RBITW","CLZW",-"MOVHU\tR",-"RBIT\t",-"CLZ\t"
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// s390x:"FLOGR","OR\t\\$65536"
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// ppc64:"POPCNTD","OR\\t\\$65536"
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// ppc64le:"POPCNTD","OR\\t\\$65536"
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return bits.TrailingZeros16(n)
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}
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func TrailingZeros8(n uint8) int {
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// amd64:"BSFL","BTSL\\t\\$8"
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// arm64:"ORR\t\\$256","RBITW","CLZW",-"MOVBU\tR",-"RBIT\t",-"CLZ\t"
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// s390x:"FLOGR","OR\t\\$256"
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return bits.TrailingZeros8(n)
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}
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// IterateBitsNN checks special handling of TrailingZerosNN when the input is known to be non-zero.
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func IterateBits(n uint) int {
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i := 0
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for n != 0 {
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// amd64:"BSFQ",-"CMOVEQ"
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i += bits.TrailingZeros(n)
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n &= n - 1
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}
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return i
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}
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func IterateBits64(n uint64) int {
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i := 0
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for n != 0 {
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// amd64:"BSFQ",-"CMOVEQ"
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i += bits.TrailingZeros64(n)
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n &= n - 1
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}
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return i
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}
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func IterateBits32(n uint32) int {
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i := 0
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for n != 0 {
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// amd64:"BSFL",-"BTSQ"
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i += bits.TrailingZeros32(n)
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n &= n - 1
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}
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return i
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}
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func IterateBits16(n uint16) int {
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i := 0
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for n != 0 {
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// amd64:"BSFL",-"BTSL"
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// arm64:"RBITW","CLZW",-"ORR"
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i += bits.TrailingZeros16(n)
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n &= n - 1
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}
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return i
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}
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func IterateBits8(n uint8) int {
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i := 0
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for n != 0 {
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// amd64:"BSFL",-"BTSL"
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// arm64:"RBITW","CLZW",-"ORR"
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i += bits.TrailingZeros8(n)
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n &= n - 1
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}
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return i
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}
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// --------------- //
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// bits.Add* //
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// --------------- //
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func Add(x, y, ci uint) (r, co uint) {
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// amd64:"NEGL","ADCQ","SBBQ","NEGQ"
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return bits.Add(x, y, ci)
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}
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func AddC(x, ci uint) (r, co uint) {
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// amd64:"NEGL","ADCQ","SBBQ","NEGQ"
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return bits.Add(x, 7, ci)
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}
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func AddZ(x, y uint) (r, co uint) {
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// amd64:"ADDQ","SBBQ","NEGQ",-"NEGL",-"ADCQ"
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return bits.Add(x, y, 0)
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}
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func AddR(x, y, ci uint) uint {
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// amd64:"NEGL","ADCQ",-"SBBQ",-"NEGQ"
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r, _ := bits.Add(x, y, ci)
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return r
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}
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func AddM(p, q, r *[3]uint) {
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var c uint
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r[0], c = bits.Add(p[0], q[0], c)
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// amd64:"ADCQ",-"NEGL",-"SBBQ",-"NEGQ"
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r[1], c = bits.Add(p[1], q[1], c)
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r[2], c = bits.Add(p[2], q[2], c)
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}
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func Add64(x, y, ci uint64) (r, co uint64) {
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// amd64:"NEGL","ADCQ","SBBQ","NEGQ"
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return bits.Add64(x, y, ci)
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}
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func Add64C(x, ci uint64) (r, co uint64) {
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// amd64:"NEGL","ADCQ","SBBQ","NEGQ"
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return bits.Add64(x, 7, ci)
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}
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func Add64Z(x, y uint64) (r, co uint64) {
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// amd64:"ADDQ","SBBQ","NEGQ",-"NEGL",-"ADCQ"
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return bits.Add64(x, y, 0)
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}
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func Add64R(x, y, ci uint64) uint64 {
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// amd64:"NEGL","ADCQ",-"SBBQ",-"NEGQ"
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r, _ := bits.Add64(x, y, ci)
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return r
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}
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func Add64M(p, q, r *[3]uint64) {
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var c uint64
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r[0], c = bits.Add64(p[0], q[0], c)
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// amd64:"ADCQ",-"NEGL",-"SBBQ",-"NEGQ"
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r[1], c = bits.Add64(p[1], q[1], c)
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r[2], c = bits.Add64(p[2], q[2], c)
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}
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// --------------- //
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// bits.Sub* //
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// --------------- //
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func Sub(x, y, ci uint) (r, co uint) {
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// amd64:"NEGL","SBBQ","NEGQ"
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return bits.Sub(x, y, ci)
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}
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func SubC(x, ci uint) (r, co uint) {
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// amd64:"NEGL","SBBQ","NEGQ"
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return bits.Sub(x, 7, ci)
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}
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func SubZ(x, y uint) (r, co uint) {
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// amd64:"SUBQ","SBBQ","NEGQ",-"NEGL"
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return bits.Sub(x, y, 0)
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}
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func SubR(x, y, ci uint) uint {
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// amd64:"NEGL","SBBQ",-"NEGQ"
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r, _ := bits.Sub(x, y, ci)
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return r
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}
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func SubM(p, q, r *[3]uint) {
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var c uint
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r[0], c = bits.Sub(p[0], q[0], c)
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// amd64:"SBBQ",-"NEGL",-"NEGQ"
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r[1], c = bits.Sub(p[1], q[1], c)
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r[2], c = bits.Sub(p[2], q[2], c)
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}
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func Sub64(x, y, ci uint64) (r, co uint64) {
|
|
// amd64:"NEGL","SBBQ","NEGQ"
|
|
return bits.Sub64(x, y, ci)
|
|
}
|
|
|
|
func Sub64C(x, ci uint64) (r, co uint64) {
|
|
// amd64:"NEGL","SBBQ","NEGQ"
|
|
return bits.Sub64(x, 7, ci)
|
|
}
|
|
|
|
func Sub64Z(x, y uint64) (r, co uint64) {
|
|
// amd64:"SUBQ","SBBQ","NEGQ",-"NEGL"
|
|
return bits.Sub64(x, y, 0)
|
|
}
|
|
|
|
func Sub64R(x, y, ci uint64) uint64 {
|
|
// amd64:"NEGL","SBBQ",-"NEGQ"
|
|
r, _ := bits.Sub64(x, y, ci)
|
|
return r
|
|
}
|
|
func Sub64M(p, q, r *[3]uint64) {
|
|
var c uint64
|
|
r[0], c = bits.Sub64(p[0], q[0], c)
|
|
// amd64:"SBBQ",-"NEGL",-"NEGQ"
|
|
r[1], c = bits.Sub64(p[1], q[1], c)
|
|
r[2], c = bits.Sub64(p[2], q[2], c)
|
|
}
|
|
|
|
// --------------- //
|
|
// bits.Mul* //
|
|
// --------------- //
|
|
|
|
func Mul(x, y uint) (hi, lo uint) {
|
|
// amd64:"MULQ"
|
|
// arm64:"UMULH","MUL"
|
|
// ppc64:"MULHDU","MULLD"
|
|
// ppc64le:"MULHDU","MULLD"
|
|
return bits.Mul(x, y)
|
|
}
|
|
|
|
func Mul64(x, y uint64) (hi, lo uint64) {
|
|
// amd64:"MULQ"
|
|
// arm64:"UMULH","MUL"
|
|
// ppc64:"MULHDU","MULLD"
|
|
// ppc64le:"MULHDU","MULLD"
|
|
return bits.Mul64(x, y)
|
|
}
|
|
|
|
// --------------- //
|
|
// bits.Div* //
|
|
// --------------- //
|
|
|
|
func Div(hi, lo, x uint) (q, r uint) {
|
|
// amd64:"DIVQ"
|
|
return bits.Div(hi, lo, x)
|
|
}
|
|
|
|
func Div32(hi, lo, x uint32) (q, r uint32) {
|
|
// arm64:"ORR","UDIV","MSUB",-"UREM"
|
|
return bits.Div32(hi, lo, x)
|
|
}
|
|
|
|
func Div64(hi, lo, x uint64) (q, r uint64) {
|
|
// amd64:"DIVQ"
|
|
return bits.Div64(hi, lo, x)
|
|
}
|