ref: bf2a0ea2464a89431888f01af4f5b5c0bbe62105
dir: /builtins.amd64.s/
TEXT memcpyf(SB),1,$0 MOVQ RARG, DI MOVQ DI, AX MOVQ p2+8(FP), SI MOVL n+16(FP), CX CLD; REP; MOVSB RET TEXT __builtin_clz(SB),1,$0 BYTE $0x0F; BYTE $0xBD; BYTE $0xC5 /* BSRL RARG, AX */ XORL $31, AX RET TEXT __builtin_bswap32(SB),1,$0 MOVQ RARG, AX BYTE $0x0F; BYTE $0xC8 /* BSWAP32 AX */ RET