| lh | 9ed821d | 2023-04-07 01:36:19 -0700 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright (c) 2002 ARM Ltd |
| 3 | * All rights reserved. |
| 4 | * |
| 5 | * Redistribution and use in source and binary forms, with or without |
| 6 | * modification, are permitted provided that the following conditions |
| 7 | * are met: |
| 8 | * 1. Redistributions of source code must retain the above copyright |
| 9 | * notice, this list of conditions and the following disclaimer. |
| 10 | * 2. Redistributions in binary form must reproduce the above copyright |
| 11 | * notice, this list of conditions and the following disclaimer in the |
| 12 | * documentation and/or other materials provided with the distribution. |
| 13 | * 3. The name of the company may not be used to endorse or promote |
| 14 | * products derived from this software without specific prior written |
| 15 | * permission. |
| 16 | * |
| 17 | * THIS SOFTWARE IS PROVIDED BY ARM LTD ``AS IS'' AND ANY EXPRESS OR IMPLIED |
| 18 | * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF |
| 19 | * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
| 20 | * IN NO EVENT SHALL ARM LTD BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| 21 | * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED |
| 22 | * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR |
| 23 | * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF |
| 24 | * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING |
| 25 | * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS |
| 26 | * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 27 | * |
| 28 | * Adapted for uClibc from NetBSD memcmp.S, version 1.2 2003/04/05 |
| 29 | * by Erik Andersen <andersen@codepoet.org> |
| 30 | */ |
| 31 | |
| 32 | #include <features.h> |
| 33 | #include <bits/arm_asm.h> |
| 34 | |
| 35 | .text |
| 36 | .global memcmp |
| 37 | .type memcmp,%function |
| 38 | .align 4 |
| 39 | |
| 40 | #if defined(THUMB1_ONLY) |
| 41 | .thumb_func |
| 42 | memcmp: |
| 43 | cmp r2, #0 |
| 44 | bne 1f |
| 45 | mov r0, #0 |
| 46 | bx lr |
| 47 | 1: |
| 48 | push {r4} |
| 49 | add r4, r0, r2 |
| 50 | 2: |
| 51 | ldrb r2, [r0] |
| 52 | add r0, r0, #1 |
| 53 | ldrb r3, [r1] |
| 54 | add r1, r1, #1 |
| 55 | cmp r4, r0 |
| 56 | beq 3f |
| 57 | cmp r2, r3 |
| 58 | beq 2b |
| 59 | 3: |
| 60 | sub r0, r2, r3 |
| 61 | pop {r4} |
| 62 | bx lr |
| 63 | #else |
| 64 | memcmp: |
| 65 | /* if ((len - 1) < 0) return 0 */ |
| 66 | subs r2, r2, #1 |
| 67 | IT(tt, mi) |
| 68 | movmi r0, #0 |
| 69 | #if defined(__USE_BX__) |
| 70 | bxmi lr |
| 71 | #else |
| 72 | movmi pc, lr |
| 73 | #endif |
| 74 | /* ip == last src address to compare */ |
| 75 | add ip, r0, r2 |
| 76 | 1: |
| 77 | ldrb r2, [r0], #1 |
| 78 | ldrb r3, [r1], #1 |
| 79 | cmp ip, r0 |
| 80 | IT(t, cs) |
| 81 | cmpcs r2, r3 |
| 82 | beq 1b |
| 83 | sub r0, r2, r3 |
| 84 | #if defined(__USE_BX__) |
| 85 | bx lr |
| 86 | #else |
| 87 | mov pc, lr |
| 88 | #endif |
| 89 | #endif |
| 90 | |
| 91 | .size memcmp,.-memcmp |
| 92 | |
| 93 | libc_hidden_def(memcmp) |
| 94 | #ifdef __UCLIBC_SUSV3_LEGACY__ |
| 95 | strong_alias(memcmp,bcmp) |
| 96 | #endif |