1 /* 2 * Copyright (C) 2010 The Android Open Source Project 3 * Copyright (c) 2008 ARM Ltd 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. The name of the company may not be used to endorse or promote 15 * products derived from this software without specific prior written 16 * permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY ARM LTD ``AS IS'' AND ANY EXPRESS OR IMPLIED 19 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 20 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 21 * IN NO EVENT SHALL ARM LTD BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 22 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED 23 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 24 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 25 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 26 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 27 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 * 29 * Android adaptation and tweak by Jim Huang <jserv (at) 0xlab.org>. 30 */ 31 32 #include <machine/cpu-features.h> 33 #include <machine/asm.h> 34 35 ENTRY(strcpy) 36 PLD(r1, #0) 37 eor r2, r0, r1 38 mov ip, r0 39 tst r2, #3 40 bne 4f 41 tst r1, #3 42 bne 3f 43 5: 44 str r5, [sp, #-4]! 45 mov r5, #0x01 46 orr r5, r5, r5, lsl #8 47 orr r5, r5, r5, lsl #16 48 49 str r4, [sp, #-4]! 50 tst r1, #4 51 ldr r3, [r1], #4 52 beq 2f 53 sub r2, r3, r5 54 bics r2, r2, r3 55 tst r2, r5, lsl #7 56 itt eq 57 streq r3, [ip], #4 58 ldreq r3, [r1], #4 59 bne 1f 60 /* Inner loop. We now know that r1 is 64-bit aligned, so we 61 can safely fetch up to two words. This allows us to avoid 62 load stalls. */ 63 .p2align 2 64 2: 65 PLD(r1, #8) 66 ldr r4, [r1], #4 67 sub r2, r3, r5 68 bics r2, r2, r3 69 tst r2, r5, lsl #7 70 sub r2, r4, r5 71 bne 1f 72 str r3, [ip], #4 73 bics r2, r2, r4 74 tst r2, r5, lsl #7 75 itt eq 76 ldreq r3, [r1], #4 77 streq r4, [ip], #4 78 beq 2b 79 mov r3, r4 80 1: 81 #ifdef __ARMEB__ 82 rors r3, r3, #24 83 #endif 84 strb r3, [ip], #1 85 tst r3, #0xff 86 #ifdef __ARMEL__ 87 ror r3, r3, #8 88 #endif 89 bne 1b 90 ldr r4, [sp], #4 91 ldr r5, [sp], #4 92 bx lr 93 94 /* Strings have the same offset from word alignment, but it's 95 not zero. */ 96 3: 97 tst r1, #1 98 beq 1f 99 ldrb r2, [r1], #1 100 strb r2, [ip], #1 101 cmp r2, #0 102 it eq 103 bxeq lr 104 1: 105 tst r1, #2 106 beq 5b 107 ldrh r2, [r1], #2 108 #ifdef __ARMEB__ 109 tst r2, #0xff00 110 iteet ne 111 strneh r2, [ip], #2 112 lsreq r2, r2, #8 113 streqb r2, [ip] 114 tstne r2, #0xff 115 #else 116 tst r2, #0xff 117 itet ne 118 strneh r2, [ip], #2 119 streqb r2, [ip] 120 tstne r2, #0xff00 121 #endif 122 bne 5b 123 bx lr 124 125 /* src and dst do not have a common word-alignement. Fall back to 126 byte copying. */ 127 4: 128 ldrb r2, [r1], #1 129 strb r2, [ip], #1 130 cmp r2, #0 131 bne 4b 132 bx lr 133 END(strcpy) 134
