a8599e090f
For some reason, libc exports the symbol .cerror (HIDENAME(cerror)), albeit in the FBSDprivate_1.0 version. It looks like there is no reason for this since it is not used from other libraries. Given that it cannot be accessed from C and its strange calling convention, it is rather unlikely that other things rely on it. Perhaps it is from a time when symbols could not be hidden. Not exporting .cerror causes it to be jumped to directly instead of via the PLT. This change also takes advantage of .cerror's new status by not saving and loading %ebx before jumping to it. (Therefore, .cerror now saves and loads %ebx itself.) Where there was a conditional jump to a jump to .cerror, the conditional jump has been changed to jump to .cerror directly (many modern CPUs don't do static prediction and in any case it is not much of a benefit anyway). This change makes libc.so.7 a few kilobytes smaller. Reviewed by: kib
53 lines
2.1 KiB
ArmAsm
53 lines
2.1 KiB
ArmAsm
/*-
|
|
* Copyright (c) 1990 The Regents of the University of California.
|
|
* All rights reserved.
|
|
*
|
|
* This code is derived from software contributed to Berkeley by
|
|
* William Jolitz.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. 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.
|
|
* 4. Neither the name of the University nor the names of its contributors
|
|
* may be used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
|
|
*/
|
|
|
|
#if defined(SYSLIBC_SCCS) && !defined(lint)
|
|
.asciz "@(#)syscall.s 5.1 (Berkeley) 4/23/90"
|
|
#endif /* SYSLIBC_SCCS and not lint */
|
|
#include <machine/asm.h>
|
|
__FBSDID("$FreeBSD$");
|
|
|
|
#include "SYS.h"
|
|
|
|
ENTRY(syscall)
|
|
pop %ecx /* rta */
|
|
pop %eax /* syscall number */
|
|
push %ecx
|
|
KERNCALL
|
|
push %ecx /* need to push a word to keep stack frame intact
|
|
upon return; the word must be the return address. */
|
|
jb HIDENAME(cerror)
|
|
ret
|
|
END(syscall)
|
|
|
|
.section .note.GNU-stack,"",%progbits
|