TEXT strchr(SB), $0 MOVBU c+4(FP), R1 CMP $0, R1 BEQ _null _strchr: /* not looking for a null, byte at a time */ MOVBU.P 1(R0), R2 CMP R1, R2 BEQ _sub1 CMP $0, R2 BNE _strchr _return0: /* character not found in string, return 0 */ MOVW $0, R0 RET _null: /* looking for null, align */ AND.S $3, R0, R2 BEQ _aligned MOVBU.P 1(R0), R4 CMP $0, R4 BEQ _sub1 B _null _aligned: MOVW $0xFF, R3 /* mask */ _loop: MOVW.P 4(R0), R4 /* 4 at a time */ TST R4, R3 /* AND.S R2, R3, Rx */ TST.NE R4>>8, R3 TST.NE R4>>16, R3 TST.NE R4>>24, R3 BNE _loop TST R4, R3 /* its somewhere, find it and correct */ BEQ _sub4 TST R4>>8, R3 BEQ _sub3 TST R4>>16, R3 BEQ _sub2 _sub1: /* compensate for pointer increment */ SUB $1, R0 RET_sub2: SUB $2, R0 RET_sub3: SUB $3, R0 RET_sub4: SUB $4, R0 RET
TEXT strchr(SB), $0
MOVBU c+4(FP), R1
CMP $0, R1
BEQ _null
_strchr: /* not looking for a null, byte at a time */
MOVBU.P 1(R0), R2
CMP R1, R2
BEQ _sub1
CMP $0, R2
BNE _strchr
_return0: /* character not found in string, return 0 */
MOVW $0, R0
RET
_null: /* looking for null, align */
AND.S $3, R0, R2
BEQ _aligned
MOVBU.P 1(R0), R4
CMP $0, R4
BEQ _sub1
B _null
_aligned:
MOVW $0xFF, R3 /* mask */
_loop:
MOVW.P 4(R0), R4 /* 4 at a time */
TST R4, R3 /* AND.S R2, R3, Rx */
TST.NE R4>>8, R3
TST.NE R4>>16, R3
TST.NE R4>>24, R3
BNE _loop
TST R4, R3 /* its somewhere, find it and correct */
BEQ _sub4
TST R4>>8, R3
BEQ _sub3
TST R4>>16, R3
BEQ _sub2
_sub1: /* compensate for pointer increment */
SUB $1, R0
RET
_sub2:
SUB $2, R0
RET
_sub3:
SUB $3, R0
RET
_sub4:
SUB $4, R0
RET