Improve generic strpbrk performance

With now a faster strcspn implementation, it is faster to just use
it with some return tests than reimplementing strpbrk itself.
As for strcspn optimization, it is generally at least 10 times faster
than the existing implementation on bench-strspn on a few AArch64
implementations.

Also the string/bits/string2.h inlines make no longer sense, as current
implementation will already implement most of the optimizations.

Tested on x86_64, i386, and aarch64.

	* string/strpbrk.c (strpbrk): Rewrite function.
	* string/bits/string2.h (strpbrk): Use __builtin_strpbrk.
	(__strpbrk_c2): Likewise.
	(__strpbrk_c3): Likewise.
	* string/string-inlines.c
	[SHLIB_COMPAT(libc, GLIBC_2_1_1, GLIBC_2_24)] (__strpbrk_c2):
	Likewise.
	[SHLIB_COMPAT(libc, GLIBC_2_1_1, GLIBC_2_24)] (__strpbrk_c3):
	Likewise.

4 files changed, 36 insertions, 68 deletions

diff --git a/ChangeLog b/ChangeLog
index 79e2e23398..c6f9ac7bed 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,15 @@
 2016-04-01  Adhemerval Zanella  <adhemerval.zanella@linaro.org>
 
+	* string/strpbrk.c (strpbrk): Rewrite function.
+	* string/bits/string2.h (strpbrk): Use __builtin_strpbrk.
+	(__strpbrk_c2): Likewise.
+	(__strpbrk_c3): Likewise.
+	* string/string-inlines.c
+	[SHLIB_COMPAT(libc, GLIBC_2_1_1, GLIBC_2_24)] (__strpbrk_c2):
+	Likewise.
+	[SHLIB_COMPAT(libc, GLIBC_2_1_1, GLIBC_2_24)] (__strpbrk_c3):
+	Likewise.
+
 	* string/strspn.c (strcspn): Rewrite function.
 	* string/bits/string2.h (strspn): Use __builtin_strcspn.
 	(__strspn_c1): Remove inline function.
diff --git a/string/bits/string2.h b/string/bits/string2.h
index 75a66a12e7..5a138dcba5 100644
--- a/string/bits/string2.h
+++ b/string/bits/string2.h
@@ -922,65 +922,10 @@ __stpcpy_small (char *__dest,
 
 
 /* Find the first occurrence in S of any character in ACCEPT.  */
-#if !defined _HAVE_STRING_ARCH_strpbrk || defined _FORCE_INLINES
-# ifndef _HAVE_STRING_ARCH_strpbrk
-#  if __GNUC_PREREQ (3, 2)
-#   define strpbrk(s, accept) \
-  __extension__								      \
-  ({ char __a0, __a1, __a2;						      \
-     (__builtin_constant_p (accept) && __string2_1bptr_p (accept)	      \
-      ? ((__builtin_constant_p (s) && __string2_1bptr_p (s))		      \
-	 ? __builtin_strpbrk (s, accept)				      \
-	 : ((__a0 = ((const char  *) (accept))[0], __a0 == '\0')	      \
-	    ? ((void) (s), (char *) NULL)				      \
-	    : ((__a1 = ((const char *) (accept))[1], __a1 == '\0')	      \
-	       ? __builtin_strchr (s, __a0)				      \
-	       : ((__a2 = ((const char *) (accept))[2], __a2 == '\0')	      \
-		  ? __strpbrk_c2 (s, __a0, __a1)			      \
-		  : (((const char *) (accept))[3] == '\0'		      \
-		     ? __strpbrk_c3 (s, __a0, __a1, __a2)		      \
-		     : __builtin_strpbrk (s, accept))))))		      \
-      : __builtin_strpbrk (s, accept)); })
-#  else
-#   define strpbrk(s, accept) \
-  __extension__								      \
-  ({ char __a0, __a1, __a2;						      \
-     (__builtin_constant_p (accept) && __string2_1bptr_p (accept)	      \
-      ? ((__a0 = ((const char  *) (accept))[0], __a0 == '\0')		      \
-	 ? ((void) (s), (char *) NULL)					      \
-	 : ((__a1 = ((const char *) (accept))[1], __a1 == '\0')		      \
-	    ? strchr (s, __a0)						      \
-	    : ((__a2 = ((const char *) (accept))[2], __a2 == '\0')	      \
-	       ? __strpbrk_c2 (s, __a0, __a1)				      \
-	       : (((const char *) (accept))[3] == '\0'			      \
-		  ? __strpbrk_c3 (s, __a0, __a1, __a2)			      \
-		  : strpbrk (s, accept)))))				      \
-      : strpbrk (s, accept)); })
-#  endif
+#ifndef _HAVE_STRING_ARCH_strpbrk
+# if __GNUC_PREREQ (3, 2)
+#  define strpbrk(s, accept) __builtin_strpbrk (s, accept)
 # endif
-
-__STRING_INLINE char *__strpbrk_c2 (const char *__s, int __accept1,
-				    int __accept2);
-__STRING_INLINE char *
-__strpbrk_c2 (const char *__s, int __accept1, int __accept2)
-{
-  /* Please note that __accept1 and __accept2 never can be '\0'.  */
-  while (*__s != '\0' && *__s != __accept1 && *__s != __accept2)
-    ++__s;
-  return *__s == '\0' ? NULL : (char *) (size_t) __s;
-}
-
-__STRING_INLINE char *__strpbrk_c3 (const char *__s, int __accept1,
-				    int __accept2, int __accept3);
-__STRING_INLINE char *
-__strpbrk_c3 (const char *__s, int __accept1, int __accept2, int __accept3)
-{
-  /* Please note that __accept1 to __accept3 never can be '\0'.  */
-  while (*__s != '\0' && *__s != __accept1 && *__s != __accept2
-	 && *__s != __accept3)
-    ++__s;
-  return *__s == '\0' ? NULL : (char *) (size_t) __s;
-}
 #endif
 
 
diff --git a/string/string-inlines.c b/string/string-inlines.c
index 754b31530f..06483760c3 100644
--- a/string/string-inlines.c
+++ b/string/string-inlines.c
@@ -107,4 +107,25 @@ __old_strspn_c3 (const char *__s, int __accept1, int __accept2,
 }
 compat_symbol (libc, __old_strspn_c3, __strspn_c3, GLIBC_2_1_1);
 
+char *
+__strpbrk_c2 (const char *__s, int __accept1, int __accept2)
+{
+  /* Please note that __accept1 and __accept2 never can be '\0'.  */
+  while (*__s != '\0' && *__s != __accept1 && *__s != __accept2)
+    ++__s;
+  return *__s == '\0' ? NULL : (char *) (size_t) __s;
+}
+compat_symbol (libc, __old_strpbrk_c2, __strpbrk_c2, GLIBC_2_1_1);
+
+char *
+__strpbrk_c3 (const char *__s, int __accept1, int __accept2, int __accept3)
+{
+  /* Please note that __accept1 to __accept3 never can be '\0'.  */
+  while (*__s != '\0' && *__s != __accept1 && *__s != __accept2
+	 && *__s != __accept3)
+    ++__s;
+  return *__s == '\0' ? NULL : (char *) (size_t) __s;
+}
+compat_symbol (libc, __old_strpbrk_c3, __strpbrk_c3, GLIBC_2_1_1);
+
 #endif
diff --git a/string/strpbrk.c b/string/strpbrk.c
index fddd473ad7..1ede71994f 100644
--- a/string/strpbrk.c
+++ b/string/strpbrk.c
@@ -27,15 +27,7 @@
 char *
 STRPBRK (const char *s, const char *accept)
 {
-  while (*s != '\0')
-    {
-      const char *a = accept;
-      while (*a != '\0')
-	if (*a++ == *s)
-	  return (char *) s;
-      ++s;
-    }
-
-  return NULL;
+  s += strcspn (s, accept);
+  return *s ? (char *)s : NULL;
 }
 libc_hidden_builtin_def (strpbrk)