This change creates assembler versions of __memcpy_chk/__memset_chk
that is implemented in the memcpy/memset assembler code. This change
avoids an extra call to memcpy/memset, instead allowing a simple fall
through to occur from the chk code into the body of the real
implementation.
Testing:
- Ran the libc_test on __memcpy_chk/__memset_chk on all nexus devices.
- Wrote a small test executable that has three calls to __memcpy_chk and
  three calls to __memset_chk. First call dest_len is length + 1. Second
  call dest_len is length. Third call dest_len is length - 1.
  Verified that the first two calls pass, and the third fails. Examined
  the logcat output on all nexus devices to verify that the fortify
  error message was sent properly.
- I benchmarked the new __memcpy_chk and __memset_chk on all systems. For
  __memcpy_chk and large copies, the savings is relatively small (about 1%).
  For small copies, the savings is large on cortex-a15/krait devices
  (between 5% to 30%).
  For cortex-a9 and small copies, the speed up is present, but relatively
  small (about 3% to 5%).
  For __memset_chk and large copies, the savings is also small (about 1%).
  However, all processors show larger speed-ups on small copies (about 30% to
  100%).
Bug: 9293744
Merge from internal master.
(cherry-picked from 7c860db074)
Change-Id: I916ad305e4001269460ca6ebd38aaa0be8ac7f52
		
	
		
			
				
	
	
		
			49 lines
		
	
	
		
			2.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			49 lines
		
	
	
		
			2.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
 | 
						|
 * Copyright (C) 2013 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.
 | 
						|
 */
 | 
						|
 | 
						|
#ifndef _LIBC_EVENTS_H
 | 
						|
#define _LIBC_EVENTS_H
 | 
						|
 | 
						|
 | 
						|
// This is going to be included in assembler code so only allow #define
 | 
						|
// values instead of defining an enum.
 | 
						|
 | 
						|
#define BIONIC_EVENT_MEMCPY_BUFFER_OVERFLOW   80100
 | 
						|
#define BIONIC_EVENT_STRCAT_BUFFER_OVERFLOW   80105
 | 
						|
#define BIONIC_EVENT_MEMMOVE_BUFFER_OVERFLOW  80110
 | 
						|
#define BIONIC_EVENT_STRNCAT_BUFFER_OVERFLOW  80115
 | 
						|
#define BIONIC_EVENT_STRNCPY_BUFFER_OVERFLOW  80120
 | 
						|
#define BIONIC_EVENT_MEMSET_BUFFER_OVERFLOW   80125
 | 
						|
#define BIONIC_EVENT_STRCPY_BUFFER_OVERFLOW   80130
 | 
						|
 | 
						|
#define BIONIC_EVENT_RESOLVER_OLD_RESPONSE    80300
 | 
						|
#define BIONIC_EVENT_RESOLVER_WRONG_SERVER    80305
 | 
						|
#define BIONIC_EVENT_RESOLVER_WRONG_QUERY     80310
 | 
						|
 | 
						|
#endif // _LIBC_EVENTS_H
 |