ref: ff2ebe6cfdacd890a74a6d2f9b0acd062d2633b7
dir: /sys/src/libc/386/memccpy.s/
TEXT memccpy(SB),$0 MOVL n+12(FP), CX CMPL CX, $0 JEQ none MOVL p2+4(FP), DI MOVBLZX c+8(FP), AX CLD /* * find the character in the second string */ REPN; SCASB JEQ found /* * if not found, set count to 'n' */ none: MOVL $0, AX MOVL n+12(FP), BX JMP memcpy /* * if found, set count to bytes thru character */ found: MOVL DI, AX SUBL p2+4(FP), AX MOVL AX, BX ADDL p1+0(FP), AX /* * copy the memory */ memcpy: MOVL p1+0(FP), DI MOVL p2+4(FP), SI /* * copy whole longs */ MOVL BX, CX SHRL $2, CX REP; MOVSL /* * copy the rest, by bytes */ ANDL $3, BX MOVL BX, CX REP; MOVSB RET