mirror of
https://github.com/autc04/Retro68.git
synced 2024-11-28 05:51:04 +00:00
196 lines
8.1 KiB
C
196 lines
8.1 KiB
C
/* Copyright (c) 2009 Xilinx, Inc. All rights reserved.
|
|
|
|
Redistribution and use in source and binary forms, with or without
|
|
modification, are permitted provided that the following conditions are
|
|
met:
|
|
|
|
1. Redistributions 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.
|
|
|
|
3. Neither the name of Xilinx 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 COPYRIGHT HOLDER 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
|
|
HOLDER 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.
|
|
|
|
|
|
FUNCTION
|
|
<<strcmp>>---character string compare
|
|
|
|
INDEX
|
|
strcmp
|
|
|
|
ANSI_SYNOPSIS
|
|
#include <string.h>
|
|
int strcmp(const char *<[a]>, const char *<[b]>);
|
|
|
|
TRAD_SYNOPSIS
|
|
#include <string.h>
|
|
int strcmp(<[a]>, <[b]>)
|
|
char *<[a]>;
|
|
char *<[b]>;
|
|
|
|
DESCRIPTION
|
|
<<strcmp>> compares the string at <[a]> to
|
|
the string at <[b]>.
|
|
|
|
RETURNS
|
|
If <<*<[a]>>> sorts lexicographically after <<*<[b]>>>,
|
|
<<strcmp>> returns a number greater than zero. If the two
|
|
strings match, <<strcmp>> returns zero. If <<*<[a]>>>
|
|
sorts lexicographically before <<*<[b]>>>, <<strcmp>> returns a
|
|
number less than zero.
|
|
|
|
PORTABILITY
|
|
<<strcmp>> is ANSI C.
|
|
|
|
<<strcmp>> requires no supporting OS subroutines.
|
|
|
|
QUICKREF
|
|
strcmp ansi pure
|
|
*/
|
|
|
|
#include <string.h>
|
|
#include <limits.h>
|
|
|
|
/* Nonzero if either X or Y is not aligned on a "long" boundary. */
|
|
#define UNALIGNED(X, Y) \
|
|
(((long)X & (sizeof (long) - 1)) | ((long)Y & (sizeof (long) - 1)))
|
|
|
|
/* DETECTNULL returns nonzero if (long)X contains a NULL byte. */
|
|
#if LONG_MAX == 2147483647L
|
|
#define DETECTNULL(X) (((X) - 0x01010101) & ~(X) & 0x80808080)
|
|
#else
|
|
#if LONG_MAX == 9223372036854775807L
|
|
#define DETECTNULL(X) (((X) - 0x0101010101010101) & ~(X) & 0x8080808080808080)
|
|
#else
|
|
#error long int is not a 32bit or 64bit type.
|
|
#endif
|
|
#endif
|
|
|
|
#ifndef DETECTNULL
|
|
#error long int is not a 32bit or 64bit byte
|
|
#endif
|
|
|
|
int
|
|
_DEFUN (strcmp, (s1, s2),
|
|
_CONST char *s1 _AND
|
|
_CONST char *s2)
|
|
{
|
|
|
|
#ifndef HAVE_HW_PCMP
|
|
|
|
#if defined(PREFER_SIZE_OVER_SPEED) || defined(__OPTIMIZE_SIZE__)
|
|
while (*s1 != '\0' && *s1 == *s2)
|
|
{
|
|
s1++;
|
|
s2++;
|
|
}
|
|
|
|
return (*(unsigned char *) s1) - (*(unsigned char *) s2);
|
|
#else
|
|
unsigned long *a1;
|
|
unsigned long *a2;
|
|
|
|
/* If s1 or s2 are unaligned, then compare bytes. */
|
|
if (!UNALIGNED (s1, s2))
|
|
{
|
|
/* If s1 and s2 are word-aligned, compare them a word at a time. */
|
|
a1 = (unsigned long*)s1;
|
|
a2 = (unsigned long*)s2;
|
|
while (*a1 == *a2)
|
|
{
|
|
/* To get here, *a1 == *a2, thus if we find a null in *a1,
|
|
then the strings must be equal, so return zero. */
|
|
if (DETECTNULL (*a1))
|
|
return 0;
|
|
|
|
a1++;
|
|
a2++;
|
|
}
|
|
|
|
/* A difference was detected in last few bytes of s1, so search bytewise */
|
|
s1 = (char*)a1;
|
|
s2 = (char*)a2;
|
|
}
|
|
|
|
while (*s1 != '\0' && *s1 == *s2)
|
|
{
|
|
s1++;
|
|
s2++;
|
|
}
|
|
return (*(unsigned char *) s1) - (*(unsigned char *) s2);
|
|
#endif /* not PREFER_SIZE_OVER_SPEED */
|
|
|
|
#else
|
|
|
|
asm volatile (" \n\
|
|
or r9, r0, r0 /* Index register */ \n\
|
|
check_alignment: \n\
|
|
andi r3, r5, 3 \n\
|
|
andi r4, r6, 3 \n\
|
|
bnei r3, try_align_args \n\
|
|
bnei r4, regular_strcmp /* At this point we don't have a choice */ \n\
|
|
cmp_loop: \n\
|
|
lw r3, r5, r9 \n\
|
|
lw r4, r6, r9 \n\
|
|
pcmpbf r7, r3, r0 /* See if there is Null byte */ \n\
|
|
bnei r7, end_cmp_loop /* IF yes (r7 > 0) use byte compares in end_cmp_loop */ \n\
|
|
cmpu r7, r4, r3 /* ELSE compare whole word */ \n\
|
|
bnei r7, end_cmp \n\
|
|
brid cmp_loop \n\
|
|
addik r9, r9, 4 /* delay slot */ \n\
|
|
end_cmp_loop: \n\
|
|
lbu r3, r5, r9 /* byte compare loop */ \n\
|
|
lbu r4, r6, r9 \n\
|
|
cmpu r7, r4, r3 /* Compare bytes */ \n\
|
|
bnei r7, end_cmp_early \n\
|
|
bneid r3, end_cmp_loop /* If reached null on one string, terminate */ \n\
|
|
addik r9, r9, 1 /* delay slot */ \n\
|
|
end_cmp_early: \n\
|
|
rtsd r15, 8 \n\
|
|
or r3, r0, r7 \n\
|
|
try_align_args: \n\
|
|
xor r7, r4, r3 \n\
|
|
bnei r7, regular_strcmp /* cannot align args */ \n\
|
|
rsubik r10, r3, 4 /* Number of initial bytes to align */ \n\
|
|
align_loop: \n\
|
|
lbu r3, r5, r9 \n\
|
|
lbu r4, r6, r9 \n\
|
|
cmpu r7, r4, r3 \n\
|
|
bnei r7, end_cmp \n\
|
|
beqi r3, end_cmp \n\
|
|
addik r10, r10, -1 \n\
|
|
beqid r10, cmp_loop \n\
|
|
addik r9, r9, 1 \n\
|
|
bri align_loop \n\
|
|
regular_strcmp: \n\
|
|
lbu r3, r5, r9 \n\
|
|
lbu r4, r6, r9 \n\
|
|
cmpu r7, r4, r3 \n\
|
|
bnei r7, end_cmp \n\
|
|
beqi r3, end_cmp \n\
|
|
brid regular_strcmp \n\
|
|
addik r9, r9, 1 \n\
|
|
end_cmp: \n\
|
|
rtsd r15, 8 \n\
|
|
or r3, r0, r7 /* Return strcmp result */");
|
|
|
|
#endif /* ! HAVE_HW_PCMP */
|
|
}
|
|
|