[v5] Remove defines to builtins in string2.h

Message ID VI1PR0802MB2621A7D46D8D571530AF9430832F0@VI1PR0802MB2621.eurprd08.prod.outlook.com
State Superseded
Headers

Commit Message

Wilco Dijkstra March 7, 2017, 3:29 p.m. UTC
  ping


From: Wilco Dijkstra
Sent: 10 February 2017 19:09
To: Joseph Myers
Cc: Florian Weimer; libc-alpha@sourceware.org; nd
Subject: Re: [PATCH v5] Remove defines to builtins in string2.h
    
Here is v5 of the patch rebased so it applies cleanly again on latest trunk
with https://sourceware.org/ml/libc-alpha/2017-02/msg00220.html (they are
independent but it seems to confuse patch somehow).


It now removes the _HAVE_STRING_ARCH_str(n)cmp defines too.

As discussed in     https://sourceware.org/ml/libc-alpha/2016-11/msg00625.html,
there is no need to use a define to redirect to the GCC builtin as an 
optimization (other headers already ensure symbols are redirected if
necessary to avoid name space clashes, for example when using non-C90 symbols).

Remove all redundant redirects from string/bits/string2.h. The strncat define
is redundant since _USE_STRING_ARCH_strchr is not defined for any target,
except for x86 where it may be defined, but if it is, this redirect is then
unused.

Redirects are kept for __bzero and __stpcpy as these are used in a few places
in GLIBC (and so using GCC builtins is a useful optimization) - when those
uses have been changed, the redirects can be removed too.

All unused _HAVE_STRING_ARCH_* defines are removed - this has no effect as they
are defined but not used or used in a #ifndef but not defined.

Verified no differences on AArch64 in all .so files in the install.

ChangeLog:
2015-11-23  Wilco Dijkstra  <wdijkstr@arm.com>

        * string/string-inlines.c: Remove include of bits/string2.h.
        * string/bits/string2.h (__bzero): Always redirect to memset.
        (strchr) Remove define.
        (__stpcpy): Keep redirection for internal use.
        (stpcpy): Remove define.
        (strncpy): Likewise.
        (strncat): Likewise.
        (_HAVE_STRING_ARCH_strcmp): Likewise.
        (_HAVE_STRING_ARCH_strncmp): Likewise.
        (strcspn): Likewise.
        (strspn): Likewise.
        (strpbrk): Likewise.
        (_HAVE_STRING_ARCH_strdup): Likewise.
        (_HAVE_STRING_ARCH_strndup): Likewise.
        * sysdeps/s390/bits/string.h (_HAVE_STRING_ARCH_strlen): Remove.
        (_HAVE_STRING_ARCH_strcpy): Likewise.
        (_HAVE_STRING_ARCH_strncpy): Likewise.
        (_HAVE_STRING_ARCH_strcat): Likewise.
        (_HAVE_STRING_ARCH_strncat): Likewise.
        (_HAVE_STRING_ARCH_memchr): Likewise.
        (_HAVE_STRING_ARCH_strcmp): Remove, define strcmp.
        * sysdeps/sparc/bits/string.h (_HAVE_STRING_ARCH_strchr): Remove.
        * sysdeps/x86/bits/string.h (_HAVE_STRING_ARCH_memcpy): Remove.
        (_HAVE_STRING_ARCH_memmove): Likewise.
        (_HAVE_STRING_ARCH_memcmp): Likewise.
        (_HAVE_STRING_ARCH_memset): Likewise.
        (_USE_STRING_ARCH_memset): Likewise.
        (_HAVE_STRING_ARCH_memchr): Likewise.
        (_HAVE_STRING_ARCH_memrchr): Likewise.
        (_HAVE_STRING_ARCH_rawmemchr): Likewise.
        (_HAVE_STRING_ARCH_strlen): Likewise.
        (_HAVE_STRING_ARCH_strcpy): Likewise.
        (_HAVE_STRING_ARCH_strpcpy): Likewise.
        (_HAVE_STRING_ARCH_strncpy): Likewise.
        (_HAVE_STRING_ARCH_strncat): Likewise.
        (_HAVE_STRING_ARCH_strcmp): Likewise.
        (_HAVE_STRING_ARCH_strncmp): Likewise.
        (_HAVE_STRING_ARCH_strchr): Likewise.
        (_USE_STRING_ARCH_strchr): Likewise.
        (_HAVE_STRING_ARCH_strnchr): Likewise.
        (_HAVE_STRING_ARCH_strchrnul): Likewise.
        (_HAVE_STRING_ARCH_strrchr): Likewise.
        (_HAVE_STRING_ARCH_index): Likewise.
        (_HAVE_STRING_ARCH_rindex): Likewise.
        (_HAVE_STRING_ARCH_strcspn): Likewise.
        (_HAVE_STRING_ARCH_strspn): Likewise.
        (_HAVE_STRING_ARCH_strpbrk): Likewise.
        (_HAVE_STRING_ARCH_strstr): Likewise.
        (_HAVE_STRING_ARCH_ffs): Likewise.
 
---
  

Patch

diff --git a/string/bits/string2.h b/string/bits/string2.h
index d9acf8029d90b6eeb6db3b76bae4d419756a61e5..3987f616a241e814fe9636a54c321361c3ef78a4 100644
--- a/string/bits/string2.h
+++ b/string/bits/string2.h
@@ -53,47 +53,15 @@ 
   ((size_t)(const void *)((__x) + 1) - (size_t)(const void *)(__x) == 1)
 
 /* Set N bytes of S to 0.  */
-#if !defined _HAVE_STRING_ARCH_memset
-# define __bzero(s, n) __builtin_memset (s, '\0', n)
-#endif
-
+#define __bzero(s, n) __builtin_memset (s, '\0', n)
 
 /* Copy SRC to DEST, returning pointer to final NUL byte.  */
-#ifdef __USE_GNU
-# ifndef _HAVE_STRING_ARCH_stpcpy
-#  define __stpcpy(dest, src) __builtin_stpcpy (dest, src)
-/* In glibc we use this function frequently but for namespace reasons
-   we have to use the name `__stpcpy'.  */
-#  define stpcpy(dest, src) __stpcpy (dest, src)
-# endif
-#endif
-
-
-/* Copy no more than N characters of SRC to DEST.  */
-#ifndef _HAVE_STRING_ARCH_strncpy
-# define strncpy(dest, src, n) __builtin_strncpy (dest, src, n)
-#endif
-
-
-/* Append no more than N characters from SRC onto DEST.  */
-#ifndef _HAVE_STRING_ARCH_strncat
-# ifdef _USE_STRING_ARCH_strchr
-#  define strncat(dest, src, n) \
-  (__extension__ ({ char *__dest = (dest);                                   \
-                   __builtin_constant_p (src) && __builtin_constant_p (n)    \
-                   ? (strlen (src) < ((size_t) (n))                           \
-                      ? strcat (__dest, src)                                  \
-                      : (*((char *) __mempcpy (strchr (__dest, '\0'),         \
-                                               src, n)) = '\0', __dest))     \
-                   : strncat (dest, src, n); }))
-# else
-#  define strncat(dest, src, n) __builtin_strncat (dest, src, n)
-# endif
+#ifndef __stpcpy
+# define __stpcpy(dest, src) __builtin_stpcpy (dest, src)
 #endif
 
-
 /* Compare characters of S1 and S2.  */
-#ifndef _HAVE_STRING_ARCH_strcmp
+#ifndef strcmp
 # define strcmp(s1, s2) \
   __extension__                                                                      \
   ({ size_t __s1_len, __s2_len;                                                      \
@@ -139,7 +107,7 @@ 
 
 
 /* Compare N characters of S1 and S2.  */
-#ifndef _HAVE_STRING_ARCH_strncmp
+#ifndef strncmp
 # define strncmp(s1, s2, n)                                                   \
   (__extension__ (__builtin_constant_p (n)                                   \
                   && ((__builtin_constant_p (s1)                       \
@@ -150,26 +118,6 @@ 
 #endif
 
 
-/* Return the length of the initial segment of S which
-   consists entirely of characters not in REJECT.  */
-#ifndef _HAVE_STRING_ARCH_strcspn
-# define strcspn(s, reject) __builtin_strcspn (s, reject)
-#endif
-
-
-/* Return the length of the initial segment of S which
-   consists entirely of characters in ACCEPT.  */
-#ifndef _HAVE_STRING_ARCH_strspn
-# define strspn(s, accept) __builtin_strspn (s, accept)
-#endif
-
-
-/* Find the first occurrence in S of any character in ACCEPT.  */
-#ifndef _HAVE_STRING_ARCH_strpbrk
-# define strpbrk(s, accept) __builtin_strpbrk (s, accept)
-#endif
-
-
 #ifndef _FORCE_INLINES
 # undef __STRING_INLINE
 #endif
diff --git a/string/string-inlines.c b/string/string-inlines.c
index fa4a1594b2a1558f77a9c0de7263c94b6abee763..68aa7d072aca32367708e73a891772e332ddb18d 100644
--- a/string/string-inlines.c
+++ b/string/string-inlines.c
@@ -31,7 +31,6 @@ 
 
 #undef __NO_INLINE__
 #include <bits/string.h>
-#include <bits/string2.h>
 
 #include "shlib-compat.h"
 
diff --git a/sysdeps/s390/bits/string.h b/sysdeps/s390/bits/string.h
index 1e794f925d76182ddbf9e8d59f85aa4dbc3aee20..f99a72d4cf5a6985c58a913ac61dbe2451328354 100644
--- a/sysdeps/s390/bits/string.h
+++ b/sysdeps/s390/bits/string.h
@@ -37,7 +37,6 @@ 
 # endif
 #endif
 
-#define _HAVE_STRING_ARCH_strlen 1
 #ifndef _FORCE_INLINES
 #define strlen(str) __strlen_g ((str))
 
@@ -60,7 +59,6 @@  __strlen_g (const char *__str)
 #endif
 
 /* Copy SRC to DEST.  */
-#define _HAVE_STRING_ARCH_strcpy 1
 #ifndef _FORCE_INLINES
 #define strcpy(dest, src) __strcpy_g ((dest), (src))
 
@@ -80,7 +78,6 @@  __strcpy_g (char *__dest, const char *__src)
 }
 #endif
 
-#define _HAVE_STRING_ARCH_strncpy 1
 #ifndef _FORCE_INLINES
 #define strncpy(dest, src, n) __strncpy_g ((dest), (src), (n))
 
@@ -124,7 +121,6 @@  __strncpy_g (char *__dest, const char *__src, size_t __n)
 #endif
 
 /* Append SRC onto DEST.  */
-#define _HAVE_STRING_ARCH_strcat 1
 #ifndef _FORCE_INLINES
 #define strcat(dest, src) __strcat_g ((dest), (src))
 
@@ -156,7 +152,6 @@  __strcat_g (char *__dest, const char *__src)
 #endif
 
 /* Append no more than N characters from SRC onto DEST.  */
-#define _HAVE_STRING_ARCH_strncat 1
 #ifndef _FORCE_INLINES
 #define strncat(dest, src, n) __strncat_g ((dest), (src), (n))
 
@@ -204,7 +199,6 @@  __strncat_g (char *__dest, const char *__src, size_t __n)
 #endif
 
 /* Search N bytes of S for C.  */
-#define _HAVE_STRING_ARCH_memchr 1
 #ifndef _FORCE_INLINES
 __STRING_INLINE void *
 memchr (const void *__str, int __c, size_t __n)
@@ -227,8 +221,8 @@  memchr (const void *__str, int __c, size_t __n)
 #endif
 
 /* Compare S1 and S2.  */
-#define _HAVE_STRING_ARCH_strcmp 1
 #ifndef _FORCE_INLINES
+#define strcmp(s1, s2) strcmp ((s1), (s2))
 __STRING_INLINE int
 strcmp (const char *__s1, const char *__s2)
 {
diff --git a/sysdeps/sparc/bits/string.h b/sysdeps/sparc/bits/string.h
index 4fd4e8d1de6afdf0a7e5a8b7fdb47a79894b5e71..63fa5a227f1959cb0ca04a4ce14882e1742c28d3 100644
--- a/sysdeps/sparc/bits/string.h
+++ b/sysdeps/sparc/bits/string.h
@@ -23,9 +23,5 @@ 
 /* sparc uses the aligned string inline ABI.  */
 #define _STRING_INLINE_unaligned 0
 
-/* sparc32 and sparc64 strchr(x, '\0') perform better than
-   __rawmemchr(x, '\0').  */
-#define _HAVE_STRING_ARCH_strchr 1
-
 /* Don't inline mempcpy into memcpy as sparc has an optimized mempcpy.  */
 #define _HAVE_STRING_ARCH_mempcpy 1
diff --git a/sysdeps/x86/bits/string.h b/sysdeps/x86/bits/string.h
index 94cba8e76f2bcd4edafe17bde7243bbd0e965533..cdd45282e5e24b16e229047076d8692f96806841 100644
--- a/sysdeps/x86/bits/string.h
+++ b/sysdeps/x86/bits/string.h
@@ -66,7 +66,6 @@ 
 
 
 /* Copy N bytes of SRC to DEST.  */
-# define _HAVE_STRING_ARCH_memcpy 1
 # define memcpy(dest, src, n) \
   (__extension__ (__builtin_constant_p (n)                                   \
                   ? __memcpy_c ((dest), (src), (n))                            \
@@ -155,7 +154,6 @@  __memcpy_g (void *__dest, const void *__src, size_t __n)
   return __dest;
 }
 
-# define _HAVE_STRING_ARCH_memmove 1
 # ifndef _FORCE_INLINES
 /* Copy N bytes of SRC to DEST, guaranteeing
    correct behavior for overlapping strings.  */
@@ -194,7 +192,6 @@  __memmove_g (void *__dest, const void *__src, size_t __n)
 # endif
 
 /* Compare N bytes of S1 and S2.  */
-# define _HAVE_STRING_ARCH_memcmp 1
 # ifndef _FORCE_INLINES
 #  ifndef __PIC__
 /* gcc has problems to spill registers when using PIC.  */
@@ -222,8 +219,6 @@  memcmp (const void *__s1, const void *__s2, size_t __n)
 # endif
 
 /* Set N bytes of S to C.  */
-# define _HAVE_STRING_ARCH_memset 1
-# define _USE_STRING_ARCH_memset 1
 # define memset(s, c, n) \
   (__extension__ (__builtin_constant_p (n) && (n) <= 16                              \
                   ? ((n) == 1                                                  \
@@ -449,7 +444,6 @@  __memset_gcn_by2 (void *__s, int __c, size_t __n)
 
 
 /* Search N bytes of S for C.  */
-# define _HAVE_STRING_ARCH_memchr 1
 # ifndef _FORCE_INLINES
 __STRING_INLINE void *
 memchr (const void *__s, int __c, size_t __n)
@@ -486,7 +480,6 @@  memchr (const void *__s, int __c, size_t __n)
 }
 # endif
 
-# define _HAVE_STRING_ARCH_memrchr 1
 # ifndef _FORCE_INLINES
 __STRING_INLINE void *__memrchr (const void *__s, int __c, size_t __n);
 
@@ -532,7 +525,6 @@  __memrchr (const void *__s, int __c, size_t __n)
 # endif
 
 /* Return pointer to C in S.  */
-# define _HAVE_STRING_ARCH_rawmemchr 1
 __STRING_INLINE void *__rawmemchr (const void *__s, int __c);
 
 # ifndef _FORCE_INLINES
@@ -561,7 +553,6 @@  rawmemchr (const void *__s, int __c)
 
 
 /* Return the length of S.  */
-# define _HAVE_STRING_ARCH_strlen 1
 # define strlen(str) \
   (__extension__ (__builtin_constant_p (str)                                 \
                   ? __builtin_strlen (str)                                     \
@@ -588,7 +579,6 @@  __strlen_g (const char *__str)
 
 
 /* Copy SRC to DEST.  */
-# define _HAVE_STRING_ARCH_strcpy 1
 # define strcpy(dest, src) \
   (__extension__ (__builtin_constant_p (src)                                 \
                   ? (sizeof ((src)[0]) == 1 && strlen (src) + 1 <= 8           \
@@ -673,7 +663,6 @@  __strcpy_g (char *__dest, const char *__src)
 
 
 # ifdef __USE_GNU
-#  define _HAVE_STRING_ARCH_stpcpy 1
 /* Copy SRC to DEST.  */
 #  define __stpcpy(dest, src) \
   (__extension__ (__builtin_constant_p (src)                                 \
@@ -848,7 +837,6 @@  __stpcpy_g (char *__dest, const char *__src)
 
 
 /* Copy no more than N characters of SRC to DEST.  */
-# define _HAVE_STRING_ARCH_strncpy 1
 # define strncpy(dest, src, n) \
   (__extension__ (__builtin_constant_p (src)                                 \
                   ? ((strlen (src) + 1 >= ((size_t) (n))               \
@@ -980,7 +968,6 @@  __strncpy_gg (char *__dest, const char *__src, size_t __n)
 
 
 /* Append SRC onto DEST.  */
-# define _HAVE_STRING_ARCH_strcat 1
 # define strcat(dest, src) \
   (__extension__ (__builtin_constant_p (src)                                 \
                   ? __strcat_c ((dest), (src), strlen (src) + 1)       \
@@ -1051,7 +1038,6 @@  __strcat_g (char *__dest, const char *__src)
 
 
 /* Append no more than N characters from SRC onto DEST.  */
-# define _HAVE_STRING_ARCH_strncat 1
 # define strncat(dest, src, n) \
   (__extension__ ({ char *__dest = (dest);                                   \
                     __builtin_constant_p (src) && __builtin_constant_p (n)    \
@@ -1115,7 +1101,6 @@  __strncat_g (char *__dest, const char __src[], size_t __n)
 
 
 /* Compare S1 and S2.  */
-# define _HAVE_STRING_ARCH_strcmp 1
 # define strcmp(s1, s2) \
   (__extension__ (__builtin_constant_p (s1) && __builtin_constant_p (s2)      \
                   && (sizeof ((s1)[0]) != 1 || strlen (s1) >= 4)       \
@@ -1219,7 +1204,6 @@  __strcmp_gg (const char *__s1, const char *__s2)
 
 
 /* Compare N characters of S1 and S2.  */
-# define _HAVE_STRING_ARCH_strncmp 1
 # define strncmp(s1, s2, n) \
   (__extension__ (__builtin_constant_p (s1) && strlen (s1) < ((size_t) (n))   \
                   ? strcmp ((s1), (s2))                                        \
@@ -1263,8 +1247,6 @@  __strncmp_g (const char *__s1, const char *__s2, size_t __n)
 
 
 /* Find the first occurrence of C in S.  */
-# define _HAVE_STRING_ARCH_strchr 1
-# define _USE_STRING_ARCH_strchr 1
 # define strchr(s, c) \
   (__extension__ (__builtin_constant_p (c)                                   \
                   ? ((c) == '\0'                                       \
@@ -1323,7 +1305,6 @@  __strchr_g (const char *__s, int __c)
 
 
 /* Find the first occurrence of C in S or the final NUL byte.  */
-# define _HAVE_STRING_ARCH_strchrnul 1
 # define __strchrnul(s, c) \
   (__extension__ (__builtin_constant_p (c)                                   \
                   ? ((c) == '\0'                                       \
@@ -1386,7 +1367,6 @@  __strchrnul_g (const char *__s, int __c)
 
 # if defined __USE_MISC || defined __USE_XOPEN_EXTENDED
 /* Find the first occurrence of C in S.  This is the BSD name.  */
-#  define _HAVE_STRING_ARCH_index 1
 #  define index(s, c) \
   (__extension__ (__builtin_constant_p (c)                                   \
                   ? __strchr_c ((s), ((c) & 0xff) << 8)                        \
@@ -1395,7 +1375,6 @@  __strchrnul_g (const char *__s, int __c)
 
 
 /* Find the last occurrence of C in S.  */
-# define _HAVE_STRING_ARCH_strrchr 1
 # define strrchr(s, c) \
   (__extension__ (__builtin_constant_p (c)                                   \
                   ? __strrchr_c ((s), ((c) & 0xff) << 8)               \
@@ -1500,7 +1479,6 @@  __strrchr_g (const char *__s, int __c)
 
 # if defined __USE_MISC || defined __USE_XOPEN_EXTENDED
 /* Find the last occurrence of C in S.  This is the BSD name.  */
-#  define _HAVE_STRING_ARCH_rindex 1
 #  define rindex(s, c) \
   (__extension__ (__builtin_constant_p (c)                                   \
                   ? __strrchr_c ((s), ((c) & 0xff) << 8)               \
@@ -1510,7 +1488,6 @@  __strrchr_g (const char *__s, int __c)
 
 /* Return the length of the initial segment of S which
    consists entirely of characters not in REJECT.  */
-# define _HAVE_STRING_ARCH_strcspn 1
 # define strcspn(s, reject) \
   (__extension__ (__builtin_constant_p (reject) && sizeof ((reject)[0]) == 1  \
                   ? ((reject)[0] == '\0'                               \
@@ -1631,7 +1608,6 @@  __strcspn_g (const char *__s, const char *__reject)
 
 /* Return the length of the initial segment of S which
    consists entirely of characters in ACCEPT.  */
-# define _HAVE_STRING_ARCH_strspn 1
 # define strspn(s, accept) \
   (__extension__ (__builtin_constant_p (accept) && sizeof ((accept)[0]) == 1  \
                   ? ((accept)[0] == '\0'                               \
@@ -1751,7 +1727,6 @@  __strspn_g (const char *__s, const char *__accept)
 
 
 /* Find the first occurrence in S of any character in ACCEPT.  */
-# define _HAVE_STRING_ARCH_strpbrk 1
 # define strpbrk(s, accept) \
   (__extension__ (__builtin_constant_p (accept) && sizeof ((accept)[0]) == 1  \
                   ? ((accept)[0] == '\0'                               \
@@ -1858,7 +1833,6 @@  __strpbrk_g (const char *__s, const char *__accept)
 
 
 /* Find the first occurrence of NEEDLE in HAYSTACK.  */
-# define _HAVE_STRING_ARCH_strstr 1
 # define strstr(haystack, needle) \
   (__extension__ (__builtin_constant_p (needle) && sizeof ((needle)[0]) == 1  \
                   ? ((needle)[0] == '\0'                               \
@@ -1970,7 +1944,6 @@  __strstr_g (const char *__haystack, const char *__needle)
    processors gcc generates good code.  */
 # if defined __USE_MISC || defined __USE_XOPEN_EXTENDED
 #  ifdef __i686__
-#   define _HAVE_STRING_ARCH_ffs 1
 #   define ffs(word) (__builtin_constant_p (word)                             \
                       ? __builtin_ffs (word)                                   \
                       : ({ int __cnt, __tmp;                                   \