ipld-eth-server/vendor/github.com/steakknife/hamming/popcnt_amd64.s

65 lines
1.4 KiB
ArmAsm

//
// hamming distance calculations in Go
//
// https://github.com/steakknife/hamming
//
// Copyright © 2014, 2015, 2016 Barry Allard
//
// MIT license
//
#include "textflag.h"
TEXT ·CountBitsInt8PopCnt(SB),NOSPLIT,$0
JMP ·CountBitsBytePopCnt(SB)
TEXT ·CountBitsInt16PopCnt(SB),NOSPLIT,$0
JMP ·CountBitsUint16PopCnt(SB)
TEXT ·CountBitsInt32PopCnt(SB),NOSPLIT,$0
JMP ·CountBitsUint32PopCnt(SB)
TEXT ·CountBitsInt64PopCnt(SB),NOSPLIT,$0
JMP ·CountBitsUint64PopCnt(SB)
TEXT ·CountBitsBytePopCnt(SB),NOSPLIT,$0
JMP ·CountBitsUint8PopCnt(SB)
TEXT ·CountBitsRunePopCnt(SB),NOSPLIT,$0
JMP ·CountBitsUint32PopCnt(SB)
TEXT ·CountBitsUint8PopCnt(SB),NOSPLIT,$0
XORQ AX, AX
MOVB x+0(FP), AX
POPCNTQ AX, AX
MOVQ AX, ret+8(FP)
RET
TEXT ·CountBitsUint16PopCnt(SB),NOSPLIT,$0
XORQ AX, AX
MOVW x+0(FP), AX
POPCNTQ AX, AX
MOVQ AX, ret+8(FP)
RET
TEXT ·CountBitsUint32PopCnt(SB),NOSPLIT,$0
XORQ AX, AX
MOVL x+0(FP), AX
POPCNTQ AX, AX
MOVQ AX, ret+8(FP)
RET
TEXT ·CountBitsUint64PopCnt(SB),NOSPLIT,$0
POPCNTQ x+0(FP), AX
MOVQ AX, ret+8(FP)
RET
// func hasPopCnt() (ret bool)
TEXT ·HasPopCnt(SB),NOSPLIT,$0
MOVL $1, AX
CPUID
SHRL $23, CX // bit 23: Advanced Bit Manipulation Bit (ABM) -> POPCNTQ
ANDL $1, CX
MOVB CX, ret+0(FP)
RET