mirror of
https://sourceware.org/git/glibc.git
synced 2024-12-30 14:31:14 +00:00
6dbb7062ff
1998-08-25 11:43 Ulrich Drepper <drepper@cygnus.com> * elf/elf.h: Add syminfo stuff and other DT_* from Solaris' ELF. 1998-08-25 Bernd Schmidt <crux@Pool.Informatik.RWTH-Aachen.DE> * argp/argp.h: Use __inline__ not inline. * sysdeps/i386/bits/select.h (FD_ZERO): Rewrite asm not to indicate an input register as being clobbered. * sysdeps/i386/memset.c (memset): Likewise. * sysdeps/i386/bzero.c (__bzero): Likewise. * sysdeps/i386/memcopy.h ({BYTE,WORD}_COPY_[FB]WD): Likewise. 1998-08-25 Andreas Jaeger <aj@arthur.rhein-neckar.de> * stdlib/jrand48_r.c (__jrand48_r): Set also upper half of result. Fixes PR libc/757 (Reported by Michael Creutz <creutz@bnl.gov).
85 lines
2.4 KiB
C
85 lines
2.4 KiB
C
/* Set a block of memory to some byte value.
|
|
For Intel 80x86, x>=3.
|
|
Copyright (C) 1991, 1992, 1993, 1997, 1998 Free Software Foundation, Inc.
|
|
Contributed by Torbjorn Granlund (tege@sics.se).
|
|
|
|
The GNU C Library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Library General Public License as
|
|
published by the Free Software Foundation; either version 2 of the
|
|
License, or (at your option) any later version.
|
|
|
|
The GNU C Library is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
Library General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Library General Public
|
|
License along with the GNU C Library; see the file COPYING.LIB. If not,
|
|
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
|
|
Boston, MA 02111-1307, USA. */
|
|
|
|
#include <string.h>
|
|
#include <memcopy.h>
|
|
|
|
#ifdef __GNUC__
|
|
|
|
#undef memset
|
|
|
|
void *
|
|
memset (void *dstpp, int c, size_t len)
|
|
{
|
|
int d0;
|
|
unsigned long int dstp = (unsigned long int) dstpp;
|
|
|
|
/* This explicit register allocation
|
|
improves code very much indeed. */
|
|
register op_t x asm("ax");
|
|
|
|
x = (unsigned char) c;
|
|
|
|
/* Clear the direction flag, so filling will move forward. */
|
|
asm volatile("cld");
|
|
|
|
/* This threshold value is optimal. */
|
|
if (len >= 12)
|
|
{
|
|
/* Fill X with four copies of the char we want to fill with. */
|
|
x |= (x << 8);
|
|
x |= (x << 16);
|
|
|
|
/* Adjust LEN for the bytes handled in the first loop. */
|
|
len -= (-dstp) % OPSIZ;
|
|
|
|
/* There are at least some bytes to set.
|
|
No need to test for LEN == 0 in this alignment loop. */
|
|
|
|
/* Fill bytes until DSTP is aligned on a longword boundary. */
|
|
asm volatile("rep\n"
|
|
"stosb" /* %0, %2, %3 */ :
|
|
"=D" (dstp), "=c" (d0) :
|
|
"0" (dstp), "1" ((-dstp) % OPSIZ), "a" (x) :
|
|
"memory");
|
|
|
|
/* Fill longwords. */
|
|
asm volatile("rep\n"
|
|
"stosl" /* %0, %2, %3 */ :
|
|
"=D" (dstp), "=c" (d0) :
|
|
"0" (dstp), "1" (len / OPSIZ), "a" (x) :
|
|
"memory");
|
|
len %= OPSIZ;
|
|
}
|
|
|
|
/* Write the last few bytes. */
|
|
asm volatile("rep\n"
|
|
"stosb" /* %0, %2, %3 */ :
|
|
"=D" (dstp), "=c" (d0) :
|
|
"0" (dstp), "1" (len), "a" (x) :
|
|
"memory");
|
|
|
|
return dstpp;
|
|
}
|
|
|
|
#else
|
|
#include <sysdeps/generic/memset.c>
|
|
#endif
|