Benchtests: Add benchtests for __memcmpeq

No bug. This commit adds __memcmpeq benchmarks. The benchmarks just
use the existing ones in memcmp. This will be useful for testing
implementations of __memcmpeq that do not just alias memcmp.

benchtests/Makefile

@@ -103,7 +103,7 @@ bench := $(foreach B,$(filter bench-%,${BENCHSET}), ${${B}})
 endif
 
 # String function benchmarks.
-string-benchset := memccpy memchr memcmp memcpy memmem memmove \
+string-benchset := memccpy memchr memcmp memcmpeq memcpy memmem memmove \
 		   mempcpy memset rawmemchr stpcpy stpncpy strcasecmp strcasestr \
 		   strcat strchr strchrnul strcmp strcpy strcspn strlen \
 		   strncasecmp strncat strncmp strncpy strnlen strpbrk strrchr \

benchtests/bench-memcmp.c

@@ -17,17 +17,21 @@
    <https://www.gnu.org/licenses/>.  */
 
 #define TEST_MAIN
-#ifdef WIDE
+#ifdef TEST_MEMCMPEQ
+# define TEST_NAME "__memcmpeq"
+# define SIMPLE_MEMCMP simple_memcmpeq
+#elif defined WIDE
 # define TEST_NAME "wmemcmp"
+# define SIMPLE_MEMCMP simple_wmemcmp
 #else
 # define TEST_NAME "memcmp"
+# define SIMPLE_MEMCMP simple_memcmp
 #endif
 #include "bench-string.h"
 #ifdef WIDE
 
-# define SIMPLE_MEMCMP simple_wmemcmp
 int
-simple_wmemcmp (const wchar_t *s1, const wchar_t *s2, size_t n)
+SIMPLE_MEMCMP (const wchar_t *s1, const wchar_t *s2, size_t n)
 {
   int ret = 0;
   /* Warning!
@@ -40,10 +44,8 @@ simple_wmemcmp (const wchar_t *s1, const wchar_t *s2, size_t n)
 #else
 # include <limits.h>
 
-# define SIMPLE_MEMCMP simple_memcmp
-
 int
-simple_memcmp (const char *s1, const char *s2, size_t n)
+SIMPLE_MEMCMP (const char *s1, const char *s2, size_t n)
 {
   int ret = 0;
 

benchtests/bench-memcmpeq.c

@@ -0,0 +1,20 @@
+/* Measure __memcmpeq functions.
+   Copyright (C) 2015-2021 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   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
+   <https://www.gnu.org/licenses/>.  */
+
+#define TEST_MEMCMPEQ 1
+#include "bench-memcmp.c"