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 .save {lr} 55 str lr, [sp, #-4]! 56 57 /* align the destination to a cache-line */ 58 mov r12, r1 59 mov lr, r1 60 rsb r3, r0, #0 61 ands r3, r3, #0x1C 62 beq .Laligned32 63 cmp r3, r2 64 andhi r3, r2, #0x1C 65 sub r2, r2, r3 66 67 /* conditionally writes 0 to 7 words (length in r3) */ 68 movs r3, r3, lsl #28 69 stmcsia r0!, {r1, lr} 70 stmcsia r0!, {r1, lr} 71 stmmiia r0!, {r1, lr} 72 movs r3, r3, lsl #2 73 strcs r1, [r0], #4 74 75 .Laligned32: 76 mov r3, r1 77 1: subs r2, r2, #32 78 stmhsia r0!, {r1,r3,r12,lr} 79 stmhsia r0!, {r1,r3,r12,lr} 80 bhs 1b 81 add r2, r2, #32 82 83 /* conditionally stores 0 to 30 bytes */ 84 movs r2, r2, lsl #28 85 stmcsia r0!, {r1,r3,r12,lr} 86 stmmiia r0!, {r1,lr} 87 movs r2, r2, lsl #2 88 strcs r1, [r0], #4 89 strmih lr, [r0], #2 90 91 ldr lr, [sp], #4 92 bx lr 93 .fnend 94
