| /* SPDX-License-Identifier: GPL-2.0 */ |
| // Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd. |
| |
| #include <linux/linkage.h> |
| #include "sysdep.h" |
| |
| ENTRY(memcmp) |
| /* Test if len less than 4 bytes. */ |
| mov r3, r0 |
| movi r0, 0 |
| mov r12, r4 |
| cmplti r2, 4 |
| bt .L_compare_by_byte |
| |
| andi r13, r0, 3 |
| movi r19, 4 |
| |
| /* Test if s1 is not 4 bytes aligned. */ |
| bnez r13, .L_s1_not_aligned |
| |
| LABLE_ALIGN |
| .L_s1_aligned: |
| /* If dest is aligned, then copy. */ |
| zext r18, r2, 31, 4 |
| /* Test if len less than 16 bytes. */ |
| bez r18, .L_compare_by_word |
| |
| .L_compare_by_4word: |
| /* If aligned, load word each time. */ |
| ldw r20, (r3, 0) |
| ldw r21, (r1, 0) |
| /* If s1[i] != s2[i], goto .L_byte_check. */ |
| cmpne r20, r21 |
| bt .L_byte_check |
| |
| ldw r20, (r3, 4) |
| ldw r21, (r1, 4) |
| cmpne r20, r21 |
| bt .L_byte_check |
| |
| ldw r20, (r3, 8) |
| ldw r21, (r1, 8) |
| cmpne r20, r21 |
| bt .L_byte_check |
| |
| ldw r20, (r3, 12) |
| ldw r21, (r1, 12) |
| cmpne r20, r21 |
| bt .L_byte_check |
| |
| PRE_BNEZAD (r18) |
| addi a3, 16 |
| addi a1, 16 |
| |
| BNEZAD (r18, .L_compare_by_4word) |
| |
| .L_compare_by_word: |
| zext r18, r2, 3, 2 |
| bez r18, .L_compare_by_byte |
| .L_compare_by_word_loop: |
| ldw r20, (r3, 0) |
| ldw r21, (r1, 0) |
| addi r3, 4 |
| PRE_BNEZAD (r18) |
| cmpne r20, r21 |
| addi r1, 4 |
| bt .L_byte_check |
| BNEZAD (r18, .L_compare_by_word_loop) |
| |
| .L_compare_by_byte: |
| zext r18, r2, 1, 0 |
| bez r18, .L_return |
| .L_compare_by_byte_loop: |
| ldb r0, (r3, 0) |
| ldb r4, (r1, 0) |
| addi r3, 1 |
| subu r0, r4 |
| PRE_BNEZAD (r18) |
| addi r1, 1 |
| bnez r0, .L_return |
| BNEZAD (r18, .L_compare_by_byte_loop) |
| |
| .L_return: |
| mov r4, r12 |
| rts |
| |
| # ifdef __CSKYBE__ |
| /* d[i] != s[i] in word, so we check byte 0. */ |
| .L_byte_check: |
| xtrb0 r0, r20 |
| xtrb0 r2, r21 |
| subu r0, r2 |
| bnez r0, .L_return |
| |
| /* check byte 1 */ |
| xtrb1 r0, r20 |
| xtrb1 r2, r21 |
| subu r0, r2 |
| bnez r0, .L_return |
| |
| /* check byte 2 */ |
| xtrb2 r0, r20 |
| xtrb2 r2, r21 |
| subu r0, r2 |
| bnez r0, .L_return |
| |
| /* check byte 3 */ |
| xtrb3 r0, r20 |
| xtrb3 r2, r21 |
| subu r0, r2 |
| # else |
| /* s1[i] != s2[i] in word, so we check byte 3. */ |
| .L_byte_check: |
| xtrb3 r0, r20 |
| xtrb3 r2, r21 |
| subu r0, r2 |
| bnez r0, .L_return |
| |
| /* check byte 2 */ |
| xtrb2 r0, r20 |
| xtrb2 r2, r21 |
| subu r0, r2 |
| bnez r0, .L_return |
| |
| /* check byte 1 */ |
| xtrb1 r0, r20 |
| xtrb1 r2, r21 |
| subu r0, r2 |
| bnez r0, .L_return |
| |
| /* check byte 0 */ |
| xtrb0 r0, r20 |
| xtrb0 r2, r21 |
| subu r0, r2 |
| br .L_return |
| # endif /* !__CSKYBE__ */ |
| |
| /* Compare when s1 is not aligned. */ |
| .L_s1_not_aligned: |
| sub r13, r19, r13 |
| sub r2, r13 |
| .L_s1_not_aligned_loop: |
| ldb r0, (r3, 0) |
| ldb r4, (r1, 0) |
| addi r3, 1 |
| subu r0, r4 |
| PRE_BNEZAD (r13) |
| addi r1, 1 |
| bnez r0, .L_return |
| BNEZAD (r13, .L_s1_not_aligned_loop) |
| br .L_s1_aligned |
| ENDPROC(memcmp) |
