ref: f5cc6fbe3a7bcf8bdb002c646ddd519014afafd2
dir: /libkern/strchr-386.s/
TEXT strchr(SB),$0 /* * look for null */ MOVL p+0(FP), DI MOVL $-1, CX MOVL $0, AX CLD REPN; SCASB /* * look for real char */ MOVL DI, CX MOVL p+0(FP), DI SUBL DI, CX MOVBLZX c+4(FP), AX REPN; SCASB JEQ found MOVL $0, AX RET found: MOVL DI, AX SUBL $1, AX RET