|  | /* | 
|  | * Copyright (C) 2008 The Android Open Source Project | 
|  | * All rights reserved. | 
|  | * | 
|  | * Redistribution and use in source and binary forms, with or without | 
|  | * modification, are permitted provided that the following conditions | 
|  | * are met: | 
|  | *  * Redistributions of source code must retain the above copyright | 
|  | *    notice, this list of conditions and the following disclaimer. | 
|  | *  * Redistributions in binary form must reproduce the above copyright | 
|  | *    notice, this list of conditions and the following disclaimer in | 
|  | *    the documentation and/or other materials provided with the | 
|  | *    distribution. | 
|  | * | 
|  | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS | 
|  | * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT | 
|  | * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS | 
|  | * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE | 
|  | * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, | 
|  | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, | 
|  | * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS | 
|  | * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED | 
|  | * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, | 
|  | * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT | 
|  | * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF | 
|  | * SUCH DAMAGE. | 
|  | */ | 
|  |  | 
|  | #include <machine/cpu-features.h> | 
|  | #include <private/bionic_asm.h> | 
|  | #include <private/libc_events.h> | 
|  |  | 
|  | /* | 
|  | * This code assumes it is running on a processor that supports all arm v7 | 
|  | * instructions, that supports neon instructions, and that supports | 
|  | * unaligned neon instruction accesses to memory. | 
|  | */ | 
|  |  | 
|  | .fpu    neon | 
|  | .syntax unified | 
|  |  | 
|  | ENTRY(__memset_chk) | 
|  | cmp         r2, r3 | 
|  | bls         .L_done | 
|  |  | 
|  | // Preserve lr for backtrace. | 
|  | push        {lr} | 
|  | .cfi_def_cfa_offset 4 | 
|  | .cfi_rel_offset lr, 0 | 
|  |  | 
|  | ldr         r0, error_message | 
|  | ldr         r1, error_code | 
|  | 1: | 
|  | add         r0, pc | 
|  | bl          __fortify_chk_fail | 
|  | error_code: | 
|  | .word       BIONIC_EVENT_MEMSET_BUFFER_OVERFLOW | 
|  | error_message: | 
|  | .word       error_string-(1b+8) | 
|  | END(__memset_chk) | 
|  |  | 
|  | ENTRY(bzero) | 
|  | mov     r2, r1 | 
|  | mov     r1, #0 | 
|  |  | 
|  | .L_done: | 
|  | // Fall through to memset... | 
|  | END(bzero) | 
|  |  | 
|  | /* memset() returns its first argument.  */ | 
|  | ENTRY(memset) | 
|  | mov         r3, r0 | 
|  | vdup.8      q0, r1 | 
|  |  | 
|  | /* make sure we have at least 32 bytes to write */ | 
|  | subs        r2, r2, #32 | 
|  | blo         2f | 
|  | vmov        q1, q0 | 
|  |  | 
|  | 1:      /* The main loop writes 32 bytes at a time */ | 
|  | subs        r2, r2, #32 | 
|  | vst1.8      {d0 - d3}, [r3]! | 
|  | bhs         1b | 
|  |  | 
|  | 2:      /* less than 32 left */ | 
|  | add         r2, r2, #32 | 
|  | tst         r2, #0x10 | 
|  | beq         3f | 
|  |  | 
|  | // writes 16 bytes, 128-bits aligned | 
|  | vst1.8      {d0, d1}, [r3]! | 
|  | 3:      /* write up to 15-bytes (count in r2) */ | 
|  | movs        ip, r2, lsl #29 | 
|  | bcc         1f | 
|  | vst1.8      {d0}, [r3]! | 
|  | 1:      bge         2f | 
|  | vst1.32     {d0[0]}, [r3]! | 
|  | 2:      movs        ip, r2, lsl #31 | 
|  | strbmi      r1, [r3], #1 | 
|  | strbcs      r1, [r3], #1 | 
|  | strbcs      r1, [r3], #1 | 
|  | bx          lr | 
|  | END(memset) | 
|  |  | 
|  | .data | 
|  | error_string: | 
|  | .string     "memset: prevented write past end of buffer" |