Christopher Ferris | 04954a4 | 2013-02-26 01:30:00 -0800 | [diff] [blame] | 1 | /* |
Christopher Ferris | 796cbe2 | 2013-04-08 18:35:30 -0700 | [diff] [blame] | 2 | * Copyright (C) 2013 The Android Open Source Project |
Christopher Ferris | 04954a4 | 2013-02-26 01:30:00 -0800 | [diff] [blame] | 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 | * * Redistributions of source code must retain the above copyright |
| 9 | * notice, this list of conditions and the following disclaimer. |
| 10 | * * Redistributions in binary form must reproduce the above copyright |
| 11 | * notice, this list of conditions and the following disclaimer in |
| 12 | * the documentation and/or other materials provided with the |
| 13 | * distribution. |
| 14 | * |
| 15 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| 16 | * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| 17 | * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS |
| 18 | * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE |
| 19 | * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, |
| 20 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, |
| 21 | * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS |
| 22 | * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED |
| 23 | * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, |
| 24 | * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT |
| 25 | * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 26 | * SUCH DAMAGE. |
| 27 | */ |
| 28 | |
| 29 | #include <machine/cpu-features.h> |
Elliott Hughes | 851e68a | 2014-02-19 16:53:20 -0800 | [diff] [blame^] | 30 | #include <private/bionic_asm.h> |
| 31 | #include <private/libc_events.h> |
Christopher Ferris | 04954a4 | 2013-02-26 01:30:00 -0800 | [diff] [blame] | 32 | |
Christopher Ferris | 59a13c1 | 2013-08-01 13:13:33 -0700 | [diff] [blame] | 33 | /* |
| 34 | * Optimized memset() for ARM. |
Christopher Ferris | 04954a4 | 2013-02-26 01:30:00 -0800 | [diff] [blame] | 35 | * |
| 36 | * memset() returns its first argument. |
Christopher Ferris | 59a13c1 | 2013-08-01 13:13:33 -0700 | [diff] [blame] | 37 | */ |
Christopher Ferris | 04954a4 | 2013-02-26 01:30:00 -0800 | [diff] [blame] | 38 | |
Christopher Ferris | 796cbe2 | 2013-04-08 18:35:30 -0700 | [diff] [blame] | 39 | .fpu neon |
| 40 | .syntax unified |
Christopher Ferris | 04954a4 | 2013-02-26 01:30:00 -0800 | [diff] [blame] | 41 | |
Christopher Ferris | 59a13c1 | 2013-08-01 13:13:33 -0700 | [diff] [blame] | 42 | ENTRY(__memset_chk) |
| 43 | cmp r2, r3 |
Christopher Ferris | 5f45d58 | 2013-08-07 13:09:51 -0700 | [diff] [blame] | 44 | bls .L_done |
| 45 | |
| 46 | // Preserve lr for backtrace. |
Christopher Ferris | bd7fe1d | 2013-08-20 11:20:48 -0700 | [diff] [blame] | 47 | .save {lr} |
Christopher Ferris | 5f45d58 | 2013-08-07 13:09:51 -0700 | [diff] [blame] | 48 | push {lr} |
| 49 | .cfi_def_cfa_offset 4 |
| 50 | .cfi_rel_offset lr, 0 |
Christopher Ferris | 59a13c1 | 2013-08-01 13:13:33 -0700 | [diff] [blame] | 51 | |
| 52 | ldr r0, error_message |
| 53 | ldr r1, error_code |
| 54 | 1: |
| 55 | add r0, pc |
| 56 | bl __fortify_chk_fail |
| 57 | error_code: |
| 58 | .word BIONIC_EVENT_MEMSET_BUFFER_OVERFLOW |
| 59 | error_message: |
| 60 | .word error_string-(1b+8) |
Christopher Ferris | 59a13c1 | 2013-08-01 13:13:33 -0700 | [diff] [blame] | 61 | END(__memset_chk) |
| 62 | |
Christopher Ferris | 04954a4 | 2013-02-26 01:30:00 -0800 | [diff] [blame] | 63 | ENTRY(bzero) |
Christopher Ferris | 796cbe2 | 2013-04-08 18:35:30 -0700 | [diff] [blame] | 64 | mov r2, r1 |
| 65 | mov r1, #0 |
Christopher Ferris | 5f45d58 | 2013-08-07 13:09:51 -0700 | [diff] [blame] | 66 | .L_done: |
Christopher Ferris | 04954a4 | 2013-02-26 01:30:00 -0800 | [diff] [blame] | 67 | // Fall through to memset... |
| 68 | END(bzero) |
| 69 | |
| 70 | ENTRY(memset) |
Christopher Ferris | bd7fe1d | 2013-08-20 11:20:48 -0700 | [diff] [blame] | 71 | .save {r0} |
Christopher Ferris | 04954a4 | 2013-02-26 01:30:00 -0800 | [diff] [blame] | 72 | stmfd sp!, {r0} |
Christopher Ferris | 5f45d58 | 2013-08-07 13:09:51 -0700 | [diff] [blame] | 73 | .cfi_def_cfa_offset 4 |
| 74 | .cfi_rel_offset r0, 0 |
Christopher Ferris | 04954a4 | 2013-02-26 01:30:00 -0800 | [diff] [blame] | 75 | |
Christopher Ferris | 796cbe2 | 2013-04-08 18:35:30 -0700 | [diff] [blame] | 76 | // The new algorithm is slower for copies < 16 so use the old |
| 77 | // neon code in that case. |
Christopher Ferris | 04954a4 | 2013-02-26 01:30:00 -0800 | [diff] [blame] | 78 | cmp r2, #16 |
Christopher Ferris | 5f45d58 | 2013-08-07 13:09:51 -0700 | [diff] [blame] | 79 | blo .L_set_less_than_16_unknown_align |
Christopher Ferris | 04954a4 | 2013-02-26 01:30:00 -0800 | [diff] [blame] | 80 | |
Christopher Ferris | 796cbe2 | 2013-04-08 18:35:30 -0700 | [diff] [blame] | 81 | // Use strd which requires an even and odd register so move the |
| 82 | // values so that: |
| 83 | // r0 and r1 contain the memset value |
| 84 | // r2 is the number of bytes to set |
| 85 | // r3 is the destination pointer |
| 86 | mov r3, r0 |
Christopher Ferris | 04954a4 | 2013-02-26 01:30:00 -0800 | [diff] [blame] | 87 | |
Christopher Ferris | 796cbe2 | 2013-04-08 18:35:30 -0700 | [diff] [blame] | 88 | // Copy the byte value in every byte of r1. |
| 89 | mov r1, r1, lsl #24 |
| 90 | orr r1, r1, r1, lsr #8 |
| 91 | orr r1, r1, r1, lsr #16 |
Christopher Ferris | 04954a4 | 2013-02-26 01:30:00 -0800 | [diff] [blame] | 92 | |
Christopher Ferris | 5f45d58 | 2013-08-07 13:09:51 -0700 | [diff] [blame] | 93 | .L_check_alignment: |
Christopher Ferris | 796cbe2 | 2013-04-08 18:35:30 -0700 | [diff] [blame] | 94 | // Align destination to a double word to avoid the strd crossing |
| 95 | // a cache line boundary. |
| 96 | ands ip, r3, #7 |
Christopher Ferris | 5f45d58 | 2013-08-07 13:09:51 -0700 | [diff] [blame] | 97 | bne .L_do_double_word_align |
Christopher Ferris | 04954a4 | 2013-02-26 01:30:00 -0800 | [diff] [blame] | 98 | |
Christopher Ferris | 5f45d58 | 2013-08-07 13:09:51 -0700 | [diff] [blame] | 99 | .L_double_word_aligned: |
Christopher Ferris | 796cbe2 | 2013-04-08 18:35:30 -0700 | [diff] [blame] | 100 | mov r0, r1 |
Christopher Ferris | 04954a4 | 2013-02-26 01:30:00 -0800 | [diff] [blame] | 101 | |
Christopher Ferris | 796cbe2 | 2013-04-08 18:35:30 -0700 | [diff] [blame] | 102 | subs r2, #64 |
Christopher Ferris | 5f45d58 | 2013-08-07 13:09:51 -0700 | [diff] [blame] | 103 | blo .L_set_less_than_64 |
Christopher Ferris | 04954a4 | 2013-02-26 01:30:00 -0800 | [diff] [blame] | 104 | |
Christopher Ferris | 796cbe2 | 2013-04-08 18:35:30 -0700 | [diff] [blame] | 105 | 1: // Main loop sets 64 bytes at a time. |
| 106 | .irp offset, #0, #8, #16, #24, #32, #40, #48, #56 |
| 107 | strd r0, r1, [r3, \offset] |
| 108 | .endr |
Christopher Ferris | 04954a4 | 2013-02-26 01:30:00 -0800 | [diff] [blame] | 109 | |
Christopher Ferris | 796cbe2 | 2013-04-08 18:35:30 -0700 | [diff] [blame] | 110 | add r3, #64 |
| 111 | subs r2, #64 |
| 112 | bge 1b |
| 113 | |
Christopher Ferris | 5f45d58 | 2013-08-07 13:09:51 -0700 | [diff] [blame] | 114 | .L_set_less_than_64: |
Christopher Ferris | 796cbe2 | 2013-04-08 18:35:30 -0700 | [diff] [blame] | 115 | // Restore r2 to the count of bytes left to set. |
| 116 | add r2, #64 |
| 117 | lsls ip, r2, #27 |
Christopher Ferris | 5f45d58 | 2013-08-07 13:09:51 -0700 | [diff] [blame] | 118 | bcc .L_set_less_than_32 |
Christopher Ferris | 796cbe2 | 2013-04-08 18:35:30 -0700 | [diff] [blame] | 119 | // Set 32 bytes. |
| 120 | .irp offset, #0, #8, #16, #24 |
| 121 | strd r0, r1, [r3, \offset] |
| 122 | .endr |
| 123 | add r3, #32 |
| 124 | |
Christopher Ferris | 5f45d58 | 2013-08-07 13:09:51 -0700 | [diff] [blame] | 125 | .L_set_less_than_32: |
| 126 | bpl .L_set_less_than_16 |
Christopher Ferris | 796cbe2 | 2013-04-08 18:35:30 -0700 | [diff] [blame] | 127 | // Set 16 bytes. |
| 128 | .irp offset, #0, #8 |
| 129 | strd r0, r1, [r3, \offset] |
| 130 | .endr |
| 131 | add r3, #16 |
| 132 | |
Christopher Ferris | 5f45d58 | 2013-08-07 13:09:51 -0700 | [diff] [blame] | 133 | .L_set_less_than_16: |
Christopher Ferris | 796cbe2 | 2013-04-08 18:35:30 -0700 | [diff] [blame] | 134 | // Less than 16 bytes to set. |
| 135 | lsls ip, r2, #29 |
Christopher Ferris | 5f45d58 | 2013-08-07 13:09:51 -0700 | [diff] [blame] | 136 | bcc .L_set_less_than_8 |
Christopher Ferris | 796cbe2 | 2013-04-08 18:35:30 -0700 | [diff] [blame] | 137 | |
| 138 | // Set 8 bytes. |
| 139 | strd r0, r1, [r3], #8 |
| 140 | |
Christopher Ferris | 5f45d58 | 2013-08-07 13:09:51 -0700 | [diff] [blame] | 141 | .L_set_less_than_8: |
| 142 | bpl .L_set_less_than_4 |
Christopher Ferris | 796cbe2 | 2013-04-08 18:35:30 -0700 | [diff] [blame] | 143 | // Set 4 bytes |
| 144 | str r1, [r3], #4 |
| 145 | |
Christopher Ferris | 5f45d58 | 2013-08-07 13:09:51 -0700 | [diff] [blame] | 146 | .L_set_less_than_4: |
Christopher Ferris | 796cbe2 | 2013-04-08 18:35:30 -0700 | [diff] [blame] | 147 | lsls ip, r2, #31 |
| 148 | it ne |
| 149 | strbne r1, [r3], #1 |
| 150 | itt cs |
| 151 | strbcs r1, [r3], #1 |
| 152 | strbcs r1, [r3] |
| 153 | |
| 154 | ldmfd sp!, {r0} |
| 155 | bx lr |
| 156 | |
Christopher Ferris | 5f45d58 | 2013-08-07 13:09:51 -0700 | [diff] [blame] | 157 | .L_do_double_word_align: |
Christopher Ferris | 796cbe2 | 2013-04-08 18:35:30 -0700 | [diff] [blame] | 158 | rsb ip, ip, #8 |
| 159 | sub r2, r2, ip |
| 160 | movs r0, ip, lsl #31 |
| 161 | it mi |
| 162 | strbmi r1, [r3], #1 |
| 163 | itt cs |
| 164 | strbcs r1, [r3], #1 |
| 165 | strbcs r1, [r3], #1 |
| 166 | |
| 167 | // Dst is at least word aligned by this point. |
| 168 | cmp ip, #4 |
Christopher Ferris | 5f45d58 | 2013-08-07 13:09:51 -0700 | [diff] [blame] | 169 | blo .L_double_word_aligned |
Christopher Ferris | 796cbe2 | 2013-04-08 18:35:30 -0700 | [diff] [blame] | 170 | str r1, [r3], #4 |
Christopher Ferris | 5f45d58 | 2013-08-07 13:09:51 -0700 | [diff] [blame] | 171 | b .L_double_word_aligned |
Christopher Ferris | 796cbe2 | 2013-04-08 18:35:30 -0700 | [diff] [blame] | 172 | |
Christopher Ferris | 5f45d58 | 2013-08-07 13:09:51 -0700 | [diff] [blame] | 173 | .L_set_less_than_16_unknown_align: |
Christopher Ferris | 796cbe2 | 2013-04-08 18:35:30 -0700 | [diff] [blame] | 174 | // Set up to 15 bytes. |
| 175 | vdup.8 d0, r1 |
Christopher Ferris | 04954a4 | 2013-02-26 01:30:00 -0800 | [diff] [blame] | 176 | movs ip, r2, lsl #29 |
| 177 | bcc 1f |
| 178 | vst1.8 {d0}, [r0]! |
| 179 | 1: bge 2f |
| 180 | vst1.32 {d0[0]}, [r0]! |
| 181 | 2: movs ip, r2, lsl #31 |
Christopher Ferris | 796cbe2 | 2013-04-08 18:35:30 -0700 | [diff] [blame] | 182 | it mi |
| 183 | strbmi r1, [r0], #1 |
| 184 | itt cs |
| 185 | strbcs r1, [r0], #1 |
| 186 | strbcs r1, [r0], #1 |
Christopher Ferris | 04954a4 | 2013-02-26 01:30:00 -0800 | [diff] [blame] | 187 | ldmfd sp!, {r0} |
| 188 | bx lr |
| 189 | END(memset) |
Christopher Ferris | 59a13c1 | 2013-08-01 13:13:33 -0700 | [diff] [blame] | 190 | |
| 191 | .data |
| 192 | error_string: |
Elliott Hughes | 68b6711 | 2013-10-15 17:17:05 -0700 | [diff] [blame] | 193 | .string "memset: prevented write past end of buffer" |