glibc/sysdeps/powerpc/power4/wordcopy.c

213 lines
5.0 KiB
C

/* _memcopy.c -- subroutines for memory copy functions.
Copyright (C) 1991-2014 Free Software Foundation, Inc.
This file is part of the GNU C Library.
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 Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
/* BE VERY CAREFUL IF YOU CHANGE THIS CODE...! */
#include <stddef.h>
#include <memcopy.h>
/* _wordcopy_fwd_aligned -- Copy block beginning at SRCP to
block beginning at DSTP with LEN `op_t' words (not LEN bytes!).
Both SRCP and DSTP should be aligned for memory operations on `op_t's. */
#ifndef WORDCOPY_FWD_ALIGNED
# define WORDCOPY_FWD_ALIGNED _wordcopy_fwd_aligned
#endif
void
WORDCOPY_FWD_ALIGNED (long int dstp, long int srcp, size_t len)
{
op_t a0, a1;
if (len & 1)
{
((op_t *) dstp)[0] = ((op_t *) srcp)[0];
if (len == 1)
return;
srcp += OPSIZ;
dstp += OPSIZ;
len -= 1;
}
do
{
a0 = ((op_t *) srcp)[0];
a1 = ((op_t *) srcp)[1];
((op_t *) dstp)[0] = a0;
((op_t *) dstp)[1] = a1;
srcp += 2 * OPSIZ;
dstp += 2 * OPSIZ;
len -= 2;
}
while (len != 0);
}
/* _wordcopy_fwd_dest_aligned -- Copy block beginning at SRCP to
block beginning at DSTP with LEN `op_t' words (not LEN bytes!).
DSTP should be aligned for memory operations on `op_t's, but SRCP must
*not* be aligned. */
#ifndef WORDCOPY_FWD_DEST_ALIGNED
# define WORDCOPY_FWD_DEST_ALIGNED _wordcopy_fwd_dest_aligned
#endif
void
WORDCOPY_FWD_DEST_ALIGNED (long int dstp, long int srcp, size_t len)
{
op_t a0, a1, a2;
int sh_1, sh_2;
/* Calculate how to shift a word read at the memory operation
aligned srcp to make it aligned for copy. */
sh_1 = 8 * (srcp % OPSIZ);
sh_2 = 8 * OPSIZ - sh_1;
/* Make SRCP aligned by rounding it down to the beginning of the `op_t'
it points in the middle of. */
srcp &= -OPSIZ;
a0 = ((op_t *) srcp)[0];
if (len & 1)
{
a1 = ((op_t *) srcp)[1];
((op_t *) dstp)[0] = MERGE (a0, sh_1, a1, sh_2);
if (len == 1)
return;
a0 = a1;
srcp += OPSIZ;
dstp += OPSIZ;
len -= 1;
}
do
{
a1 = ((op_t *) srcp)[1];
a2 = ((op_t *) srcp)[2];
((op_t *) dstp)[0] = MERGE (a0, sh_1, a1, sh_2);
((op_t *) dstp)[1] = MERGE (a1, sh_1, a2, sh_2);
a0 = a2;
srcp += 2 * OPSIZ;
dstp += 2 * OPSIZ;
len -= 2;
}
while (len != 0);
}
/* _wordcopy_bwd_aligned -- Copy block finishing right before
SRCP to block finishing right before DSTP with LEN `op_t' words
(not LEN bytes!). Both SRCP and DSTP should be aligned for memory
operations on `op_t's. */
#ifndef WORDCOPY_BWD_ALIGNED
# define WORDCOPY_BWD_ALIGNED _wordcopy_bwd_aligned
#endif
void
WORDCOPY_BWD_ALIGNED (long int dstp, long int srcp, size_t len)
{
op_t a0, a1;
if (len & 1)
{
srcp -= OPSIZ;
dstp -= OPSIZ;
((op_t *) dstp)[0] = ((op_t *) srcp)[0];
if (len == 1)
return;
len -= 1;
}
do
{
srcp -= 2 * OPSIZ;
dstp -= 2 * OPSIZ;
a1 = ((op_t *) srcp)[1];
a0 = ((op_t *) srcp)[0];
((op_t *) dstp)[1] = a1;
((op_t *) dstp)[0] = a0;
len -= 2;
}
while (len != 0);
}
/* _wordcopy_bwd_dest_aligned -- Copy block finishing right
before SRCP to block finishing right before DSTP with LEN `op_t'
words (not LEN bytes!). DSTP should be aligned for memory
operations on `op_t', but SRCP must *not* be aligned. */
#ifndef WORDCOPY_BWD_DEST_ALIGNED
# define WORDCOPY_BWD_DEST_ALIGNED _wordcopy_bwd_dest_aligned
#endif
void
WORDCOPY_BWD_DEST_ALIGNED (long int dstp, long int srcp, size_t len)
{
op_t a0, a1, a2;
int sh_1, sh_2;
/* Calculate how to shift a word read at the memory operation
aligned srcp to make it aligned for copy. */
sh_1 = 8 * (srcp % OPSIZ);
sh_2 = 8 * OPSIZ - sh_1;
/* Make srcp aligned by rounding it down to the beginning of the op_t
it points in the middle of. */
srcp &= -OPSIZ;
a2 = ((op_t *) srcp)[0];
if (len & 1)
{
srcp -= OPSIZ;
dstp -= OPSIZ;
a1 = ((op_t *) srcp)[0];
((op_t *) dstp)[0] = MERGE (a1, sh_1, a2, sh_2);
if (len == 1)
return;
a2 = a1;
len -= 1;
}
do
{
srcp -= 2 * OPSIZ;
dstp -= 2 * OPSIZ;
a1 = ((op_t *) srcp)[1];
a0 = ((op_t *) srcp)[0];
((op_t *) dstp)[1] = MERGE (a1, sh_1, a2, sh_2);
((op_t *) dstp)[0] = MERGE (a0, sh_1, a1, sh_2);
a2 = a0;
len -= 2;
}
while (len != 0);
}