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85c2e6110c
Check wheter the compiler has the option -fno-tree-loop-distribute-patterns to inhibit loop transformation to library calls and uses it on memset and memmove default implementation to avoid recursive calls.
92 lines
2.2 KiB
C
92 lines
2.2 KiB
C
/* Copyright (C) 1991-2013 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with the GNU C Library; if not, see
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<http://www.gnu.org/licenses/>. */
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#include <string.h>
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#include <memcopy.h>
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#undef memset
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void *
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inhibit_loop_to_libcall
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memset (dstpp, c, len)
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void *dstpp;
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int c;
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size_t len;
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{
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long int dstp = (long int) dstpp;
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if (len >= 8)
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{
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size_t xlen;
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op_t cccc;
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cccc = (unsigned char) c;
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cccc |= cccc << 8;
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cccc |= cccc << 16;
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if (OPSIZ > 4)
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/* Do the shift in two steps to avoid warning if long has 32 bits. */
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cccc |= (cccc << 16) << 16;
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/* There are at least some bytes to set.
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No need to test for LEN == 0 in this alignment loop. */
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while (dstp % OPSIZ != 0)
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{
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((byte *) dstp)[0] = c;
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dstp += 1;
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len -= 1;
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}
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/* Write 8 `op_t' per iteration until less than 8 `op_t' remain. */
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xlen = len / (OPSIZ * 8);
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while (xlen > 0)
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{
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((op_t *) dstp)[0] = cccc;
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((op_t *) dstp)[1] = cccc;
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((op_t *) dstp)[2] = cccc;
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((op_t *) dstp)[3] = cccc;
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((op_t *) dstp)[4] = cccc;
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((op_t *) dstp)[5] = cccc;
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((op_t *) dstp)[6] = cccc;
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((op_t *) dstp)[7] = cccc;
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dstp += 8 * OPSIZ;
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xlen -= 1;
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}
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len %= OPSIZ * 8;
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/* Write 1 `op_t' per iteration until less than OPSIZ bytes remain. */
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xlen = len / OPSIZ;
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while (xlen > 0)
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{
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((op_t *) dstp)[0] = cccc;
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dstp += OPSIZ;
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xlen -= 1;
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}
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len %= OPSIZ;
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}
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/* Write the last few bytes. */
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while (len > 0)
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{
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((byte *) dstp)[0] = c;
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dstp += 1;
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len -= 1;
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}
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return dstpp;
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}
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libc_hidden_builtin_def (memset)
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