X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Fmemcmp.c;h=ecba1288df947111e23b80a3a162674749404689;hb=fa1db0dd22768f09a507674a30beb5b8a87bb35f;hp=98f7ed79115c2b1a917175782b0fabebac48797b;hpb=6d8337bfc808cddc275899c03482eceb6aff8547;p=gnulib.git
diff --git a/lib/memcmp.c b/lib/memcmp.c
index 98f7ed791..ecba1288d 100644
--- a/lib/memcmp.c
+++ b/lib/memcmp.c
@@ -1,72 +1,71 @@
-/* Copyright (C) 1991, 1993 Free Software Foundation, Inc.
+/* Copyright (C) 1991, 1993, 1995, 1997-1998, 2003, 2006, 2009-2013 Free
+ Software Foundation, Inc.
+
Contributed by Torbjorn Granlund (tege@sics.se).
-NOTE: The canonical source of this file is maintained with the GNU C Library.
-Bugs can be reported to bug-glibc@prep.ai.mit.edu.
+ NOTE: The canonical source of this file is maintained with the GNU C Library.
+ Bugs can be reported to bug-glibc@prep.ai.mit.edu.
-This program is free software; you can redistribute it and/or modify it
-under the terms of the GNU General Public License as published by the
-Free Software Foundation; either version 2, or (at your option) any
-later version.
+ This program is free software: you can redistribute it and/or modify it
+ under the terms of the GNU General Public License as published by the
+ Free Software Foundation; either version 3 of the License, or any
+ later version.
-This program 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 General Public License for more details.
+ This program 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 General Public License for more details.
-You should have received a copy of the GNU General Public License
-along with this program; if not, write to the Free Software Foundation,
-Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see . */
-#ifdef HAVE_CONFIG_H
-#include "config.h"
+#ifndef _LIBC
+# include
#endif
-#undef __ptr_t
-#if defined (__cplusplus) || (defined (__STDC__) && __STDC__)
-#define __ptr_t void *
-#else /* Not C++ or ANSI C. */
-#undef const
-#define const
-#define __ptr_t char *
-#endif /* C++ or ANSI C. */
-
-#if defined (HAVE_STRING_H) || defined (_LIBC)
#include
-#endif
+
+#include
+
+#undef memcmp
#ifdef _LIBC
-#include
+# include
+# include
+
+# if __BYTE_ORDER == __BIG_ENDIAN
+# define WORDS_BIGENDIAN
+# endif
-#else /* Not in the GNU C library. */
+#else /* Not in the GNU C library. */
-#include
+# include
/* Type to use for aligned memory operations.
This should normally be the biggest type supported by a single load
and store. Must be an unsigned type. */
-#define op_t unsigned long int
-#define OPSIZ (sizeof(op_t))
+# define op_t unsigned long int
+# define OPSIZ (sizeof(op_t))
/* Threshold value for when to enter the unrolled loops. */
-#define OP_T_THRES 16
+# define OP_T_THRES 16
/* Type to use for unaligned operations. */
typedef unsigned char byte;
-#ifndef WORDS_BIGENDIAN
-#define MERGE(w0, sh_1, w1, sh_2) (((w0) >> (sh_1)) | ((w1) << (sh_2)))
-#else
-#define MERGE(w0, sh_1, w1, sh_2) (((w0) << (sh_1)) | ((w1) >> (sh_2)))
-#endif
+# ifndef WORDS_BIGENDIAN
+# define MERGE(w0, sh_1, w1, sh_2) (((w0) >> (sh_1)) | ((w1) << (sh_2)))
+# else
+# define MERGE(w0, sh_1, w1, sh_2) (((w0) << (sh_1)) | ((w1) >> (sh_2)))
+# endif
-#endif /* In the GNU C library. */
+#endif /* In the GNU C library. */
#ifdef WORDS_BIGENDIAN
-#define CMP_LT_OR_GT(a, b) ((a) > (b) ? 1 : -1)
+# define CMP_LT_OR_GT(a, b) ((a) > (b) ? 1 : -1)
#else
-#define CMP_LT_OR_GT(a, b) memcmp_bytes ((a), (b))
+# define CMP_LT_OR_GT(a, b) memcmp_bytes (a, b)
#endif
/* BE VERY CAREFUL IF YOU CHANGE THIS CODE! */
@@ -86,21 +85,21 @@ typedef unsigned char byte;
/* memcmp_bytes -- Compare A and B bytewise in the byte order of the machine.
A and B are known to be different.
This is needed only on little-endian machines. */
-#ifdef __GNUC__
+
+# ifdef __GNUC__
__inline
-#endif
+# endif
static int
-memcmp_bytes (a, b)
- op_t a, b;
+memcmp_bytes (op_t a, op_t b)
{
- long int srcp1 = (long int) &a;
- long int srcp2 = (long int) &b;
+ const byte *srcp1 = (const byte *) &a;
+ const byte *srcp2 = (const byte *) &b;
op_t a0, b0;
do
{
- a0 = ((byte *) srcp1)[0];
- b0 = ((byte *) srcp2)[0];
+ a0 = srcp1[0];
+ b0 = srcp2[0];
srcp1 += 1;
srcp2 += 1;
}
@@ -109,23 +108,21 @@ memcmp_bytes (a, b)
}
#endif
-/* memcmp_common_alignment -- Compare blocks at SRCP1 and SRCP2 with LEN `op_t'
+/* memcmp_common_alignment -- Compare blocks at SRCP1 and SRCP2 with LEN 'op_t'
objects (not LEN bytes!). Both SRCP1 and SRCP2 should be aligned for
- memory operations on `op_t's. */
-#ifdef __GNUC__
+ memory operations on 'op_t's. */
+#ifdef __GNUC__
__inline
#endif
static int
-memcmp_common_alignment (srcp1, srcp2, len)
- long int srcp1;
- long int srcp2;
- size_t len;
+memcmp_common_alignment (uintptr_t srcp1, uintptr_t srcp2, size_t len)
{
op_t a0, a1;
op_t b0, b1;
switch (len % 4)
{
+ default: /* Avoid warning about uninitialized local variables. */
case 2:
a0 = ((op_t *) srcp1)[0];
b0 = ((op_t *) srcp2)[0];
@@ -142,7 +139,7 @@ memcmp_common_alignment (srcp1, srcp2, len)
goto do2;
case 0:
if (OP_T_THRES <= 3 * OPSIZ && len == 0)
- return 0;
+ return 0;
a0 = ((op_t *) srcp1)[0];
b0 = ((op_t *) srcp2)[0];
goto do3;
@@ -153,7 +150,7 @@ memcmp_common_alignment (srcp1, srcp2, len)
srcp2 += OPSIZ;
len -= 1;
if (OP_T_THRES <= 3 * OPSIZ && len == 0)
- goto do0;
+ goto do0;
/* Fall through. */
}
@@ -162,25 +159,25 @@ memcmp_common_alignment (srcp1, srcp2, len)
a0 = ((op_t *) srcp1)[0];
b0 = ((op_t *) srcp2)[0];
if (a1 != b1)
- return CMP_LT_OR_GT (a1, b1);
+ return CMP_LT_OR_GT (a1, b1);
do3:
a1 = ((op_t *) srcp1)[1];
b1 = ((op_t *) srcp2)[1];
if (a0 != b0)
- return CMP_LT_OR_GT (a0, b0);
+ return CMP_LT_OR_GT (a0, b0);
do2:
a0 = ((op_t *) srcp1)[2];
b0 = ((op_t *) srcp2)[2];
if (a1 != b1)
- return CMP_LT_OR_GT (a1, b1);
+ return CMP_LT_OR_GT (a1, b1);
do1:
a1 = ((op_t *) srcp1)[3];
b1 = ((op_t *) srcp2)[3];
if (a0 != b0)
- return CMP_LT_OR_GT (a0, b0);
+ return CMP_LT_OR_GT (a0, b0);
srcp1 += 4 * OPSIZ;
srcp2 += 4 * OPSIZ;
@@ -197,16 +194,13 @@ memcmp_common_alignment (srcp1, srcp2, len)
}
/* memcmp_not_common_alignment -- Compare blocks at SRCP1 and SRCP2 with LEN
- `op_t' objects (not LEN bytes!). SRCP2 should be aligned for memory
- operations on `op_t', but SRCP1 *should be unaligned*. */
-#ifdef __GNUC__
+ 'op_t' objects (not LEN bytes!). SRCP2 should be aligned for memory
+ operations on 'op_t', but SRCP1 *should be unaligned*. */
+#ifdef __GNUC__
__inline
#endif
static int
-memcmp_not_common_alignment (srcp1, srcp2, len)
- long int srcp1;
- long int srcp2;
- size_t len;
+memcmp_not_common_alignment (uintptr_t srcp1, uintptr_t srcp2, size_t len)
{
op_t a0, a1, a2, a3;
op_t b0, b1, b2, b3;
@@ -219,12 +213,13 @@ memcmp_not_common_alignment (srcp1, srcp2, len)
shl = 8 * (srcp1 % OPSIZ);
shr = 8 * OPSIZ - shl;
- /* Make SRCP1 aligned by rounding it down to the beginning of the `op_t'
+ /* Make SRCP1 aligned by rounding it down to the beginning of the 'op_t'
it points in the middle of. */
srcp1 &= -OPSIZ;
switch (len % 4)
{
+ default: /* Avoid warning about uninitialized local variables. */
case 2:
a1 = ((op_t *) srcp1)[0];
a2 = ((op_t *) srcp1)[1];
@@ -242,7 +237,7 @@ memcmp_not_common_alignment (srcp1, srcp2, len)
goto do2;
case 0:
if (OP_T_THRES <= 3 * OPSIZ && len == 0)
- return 0;
+ return 0;
a3 = ((op_t *) srcp1)[0];
a0 = ((op_t *) srcp1)[1];
b0 = ((op_t *) srcp2)[0];
@@ -256,7 +251,7 @@ memcmp_not_common_alignment (srcp1, srcp2, len)
srcp2 += 1 * OPSIZ;
len -= 1;
if (OP_T_THRES <= 3 * OPSIZ && len == 0)
- goto do0;
+ goto do0;
/* Fall through. */
}
@@ -264,30 +259,30 @@ memcmp_not_common_alignment (srcp1, srcp2, len)
{
a0 = ((op_t *) srcp1)[0];
b0 = ((op_t *) srcp2)[0];
- x = MERGE(a2, shl, a3, shr);
+ x = MERGE (a2, shl, a3, shr);
if (x != b3)
- return CMP_LT_OR_GT (x, b3);
+ return CMP_LT_OR_GT (x, b3);
do3:
a1 = ((op_t *) srcp1)[1];
b1 = ((op_t *) srcp2)[1];
- x = MERGE(a3, shl, a0, shr);
+ x = MERGE (a3, shl, a0, shr);
if (x != b0)
- return CMP_LT_OR_GT (x, b0);
+ return CMP_LT_OR_GT (x, b0);
do2:
a2 = ((op_t *) srcp1)[2];
b2 = ((op_t *) srcp2)[2];
- x = MERGE(a0, shl, a1, shr);
+ x = MERGE (a0, shl, a1, shr);
if (x != b1)
- return CMP_LT_OR_GT (x, b1);
+ return CMP_LT_OR_GT (x, b1);
do1:
a3 = ((op_t *) srcp1)[3];
b3 = ((op_t *) srcp2)[3];
- x = MERGE(a1, shl, a2, shr);
+ x = MERGE (a1, shl, a2, shr);
if (x != b2)
- return CMP_LT_OR_GT (x, b2);
+ return CMP_LT_OR_GT (x, b2);
srcp1 += 4 * OPSIZ;
srcp2 += 4 * OPSIZ;
@@ -298,50 +293,47 @@ memcmp_not_common_alignment (srcp1, srcp2, len)
/* This is the right position for do0. Please don't move
it into the loop. */
do0:
- x = MERGE(a2, shl, a3, shr);
+ x = MERGE (a2, shl, a3, shr);
if (x != b3)
return CMP_LT_OR_GT (x, b3);
return 0;
}
int
-memcmp (s1, s2, len)
- const __ptr_t s1;
- const __ptr_t s2;
- size_t len;
+rpl_memcmp (const void *s1, const void *s2, size_t len)
{
op_t a0;
op_t b0;
- long int srcp1 = (long int) s1;
- long int srcp2 = (long int) s2;
+ uintptr_t srcp1 = (uintptr_t) s1;
+ uintptr_t srcp2 = (uintptr_t) s2;
op_t res;
if (len >= OP_T_THRES)
{
/* There are at least some bytes to compare. No need to test
- for LEN == 0 in this alignment loop. */
+ for LEN == 0 in this alignment loop. */
while (srcp2 % OPSIZ != 0)
- {
- a0 = ((byte *) srcp1)[0];
- b0 = ((byte *) srcp2)[0];
- srcp1 += 1;
- srcp2 += 1;
- res = a0 - b0;
- if (res != 0)
- return res;
- len -= 1;
- }
-
- /* SRCP2 is now aligned for memory operations on `op_t'.
- SRCP1 alignment determines if we can do a simple,
- aligned compare or need to shuffle bits. */
+ {
+ a0 = ((byte *) srcp1)[0];
+ b0 = ((byte *) srcp2)[0];
+ srcp1 += 1;
+ srcp2 += 1;
+ res = a0 - b0;
+ if (res != 0)
+ return res;
+ len -= 1;
+ }
+
+ /* SRCP2 is now aligned for memory operations on 'op_t'.
+ SRCP1 alignment determines if we can do a simple,
+ aligned compare or need to shuffle bits. */
if (srcp1 % OPSIZ == 0)
- res = memcmp_common_alignment (srcp1, srcp2, len / OPSIZ);
+ res = memcmp_common_alignment (srcp1, srcp2, len / OPSIZ);
else
- res = memcmp_not_common_alignment (srcp1, srcp2, len / OPSIZ);
+ res = memcmp_not_common_alignment (srcp1, srcp2, len / OPSIZ);
if (res != 0)
- return res;
+ return res;
/* Number of bytes remaining in the interval [0..OPSIZ-1]. */
srcp1 += len & -OPSIZ;
@@ -358,9 +350,14 @@ memcmp (s1, s2, len)
srcp2 += 1;
res = a0 - b0;
if (res != 0)
- return res;
+ return res;
len -= 1;
}
return 0;
}
+
+#ifdef weak_alias
+# undef bcmp
+weak_alias (memcmp, bcmp)
+#endif