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 .syntax unified 22 23 .text 24 .align 25 26 .global android_memset32 27 .type android_memset32, %function 28 .global android_memset16 29 .type android_memset16, %function 30 31 /* 32 * Optimized memset32 and memset16 for ARM. 33 * 34 * void android_memset16(uint16_t* dst, uint16_t value, size_t size); 35 * void android_memset32(uint32_t* dst, uint32_t value, size_t size); 36 * 37 */ 38 39 android_memset16: 40 .fnstart 41 cmp r2, #1 42 bxle lr 43 44 /* expand the data to 32 bits */ 45 mov r1, r1, lsl #16 46 orr r1, r1, r1, lsr #16 47 48 /* align to 32 bits */ 49 tst r0, #2 50 strhne r1, [r0], #2 51 subne r2, r2, #2 52 .fnend 53 54 android_memset32: 55 .fnstart 56 .cfi_startproc 57 str lr, [sp, #-4]! 58 .cfi_def_cfa_offset 4 59 .cfi_rel_offset lr, 0 60 61 /* align the destination to a cache-line */ 62 mov r12, r1 63 mov lr, r1 64 rsb r3, r0, #0 65 ands r3, r3, #0x1C 66 beq .Laligned32 67 cmp r3, r2 68 andhi r3, r2, #0x1C 69 sub r2, r2, r3 70 71 /* conditionally writes 0 to 7 words (length in r3) */ 72 movs r3, r3, lsl #28 73 stmiacs r0!, {r1, lr} 74 stmiacs r0!, {r1, lr} 75 stmiami r0!, {r1, lr} 76 movs r3, r3, lsl #2 77 strcs r1, [r0], #4 78 79 .Laligned32: 80 mov r3, r1 81 1: subs r2, r2, #32 82 stmiahs r0!, {r1,r3,r12,lr} 83 stmiahs r0!, {r1,r3,r12,lr} 84 bhs 1b 85 add r2, r2, #32 86 87 /* conditionally stores 0 to 30 bytes */ 88 movs r2, r2, lsl #28 89 stmiacs r0!, {r1,r3,r12,lr} 90 stmiami r0!, {r1,lr} 91 movs r2, r2, lsl #2 92 strcs r1, [r0], #4 93 strhmi lr, [r0], #2 94 95 ldr lr, [sp], #4 96 .cfi_def_cfa_offset 0 97 .cfi_restore lr 98 bx lr 99 .cfi_endproc 100 .fnend 101
