1 /* 2 * Copyright (C) 2006 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 /* 17 * memset32.S 18 * 19 */ 20 21 .text 22 .align 23 24 .global android_memset32 25 .type android_memset32, %function 26 .global android_memset16 27 .type android_memset16, %function 28 29 /* 30 * Optimized memset32 and memset16 for ARM. 31 * 32 * void android_memset16(uint16_t* dst, uint16_t value, size_t size); 33 * void android_memset32(uint32_t* dst, uint32_t value, size_t size); 34 * 35 */ 36 37 android_memset16: 38 .fnstart 39 cmp r2, #1 40 bxle lr 41 42 /* expand the data to 32 bits */ 43 mov r1, r1, lsl #16 44 orr r1, r1, r1, lsr #16 45 46 /* align to 32 bits */ 47 tst r0, #2 48 strneh r1, [r0], #2 49 subne r2, r2, #2 50 .fnend 51 52 android_memset32: 53 .fnstart 54 .cfi_startproc 55 str lr, [sp, #-4]! 56 .cfi_def_cfa_offset 4 57 .cfi_rel_offset lr, 0 58 59 /* align the destination to a cache-line */ 60 mov r12, r1 61 mov lr, r1 62 rsb r3, r0, #0 63 ands r3, r3, #0x1C 64 beq .Laligned32 65 cmp r3, r2 66 andhi r3, r2, #0x1C 67 sub r2, r2, r3 68 69 /* conditionally writes 0 to 7 words (length in r3) */ 70 movs r3, r3, lsl #28 71 stmcsia r0!, {r1, lr} 72 stmcsia r0!, {r1, lr} 73 stmmiia r0!, {r1, lr} 74 movs r3, r3, lsl #2 75 strcs r1, [r0], #4 76 77 .Laligned32: 78 mov r3, r1 79 1: subs r2, r2, #32 80 stmhsia r0!, {r1,r3,r12,lr} 81 stmhsia r0!, {r1,r3,r12,lr} 82 bhs 1b 83 add r2, r2, #32 84 85 /* conditionally stores 0 to 30 bytes */ 86 movs r2, r2, lsl #28 87 stmcsia r0!, {r1,r3,r12,lr} 88 stmmiia r0!, {r1,lr} 89 movs r2, r2, lsl #2 90 strcs r1, [r0], #4 91 strmih lr, [r0], #2 92 93 ldr lr, [sp], #4 94 .cfi_def_cfa_offset 0 95 .cfi_restore lr 96 bx lr 97 .cfi_endproc 98 .fnend 99
