Convert __builtin_expect to __glibc_(un)likely throughout elf/. zack/elf-builtin-expect-conversion

In the previous patch I didn't change a use of __builtin_expect to
__glibc_(un)likely that happened to be right next to the code I was
actually working on; Andreas asked why not, and I said that there were
a bunch more uses of __builtin_expect in that file and I would convert
them all in a separate patch.  This is that patch, converting all of
elf/.

I would appreciate someone checking over this patch very carefully
indeed.  In a whole bunch of places, __builtin_expect was used in a
way that did not map mechanically to the newer convention.  The test
suite caught one mistake; I'm not confident I didn't make any more.

Writing this patch gave me a deeper appreciation for why we _want_ to
switch to __glibc_(un)likely, but also for how difficult it can be.  I
now think that people should _not_ be asked to change existing uses of
__builtin_expect in a patch whose purpose is something else.

	* elf/dl-addr.c, elf/dl-cache.c, elf/dl-close.c, elf/dl-deps.c
	* elf/dl-environ.c, elf/dl-error-skeleton.c, elf/dl-fini.c
	* elf/dl-fptr.c, elf/dl-init.c, elf/dl-libc.c, elf/dl-minimal.c
	* elf/dl-open.c, elf/dl-reloc.c, elf/dl-runtime.c
	* elf/dl-sysdep.c, elf/dl-tls.c, elf/dl-version.c, elf/ldconfig.c
	* elf/rtld.c: Replace __builtin_expect with __glibc_likely or
	__glibc_unlikely, as appropriate, throughout.

1 files changed, 4 insertions, 4 deletions

diff --git a/elf/dl-close.c b/elf/dl-close.c
index ecd6729704..4e44bdd930 100644
--- a/elf/dl-close.c
+++ b/elf/dl-close.c
@@ -271,8 +271,8 @@ _dl_close_worker (struct link_map *map, bool force)
 	  if (imap->l_init_called)
 	    {
 	      /* When debugging print a message first.  */
-	      if (__builtin_expect (GLRO(dl_debug_mask) & DL_DEBUG_IMPCALLS,
-				    0))
+	      if (__glibc_unlikely ((GLRO(dl_debug_mask) & DL_DEBUG_IMPCALLS)
+				    != 0))
 		_dl_debug_printf ("\ncalling fini: %s [%lu]\n\n",
 				  imap->l_name, nsid);
 
@@ -782,7 +782,7 @@ _dl_close_worker (struct link_map *map, bool force)
     }
 #endif
 
-  if (__builtin_expect (ns->_ns_loaded == NULL, 0)
+  if (__glibc_unlikely (ns->_ns_loaded == NULL)
       && nsid == GL(dl_nns) - 1)
     do
       --GL(dl_nns);
@@ -833,7 +833,7 @@ _dl_close (void *_map)
      should be a detectable case and given that dlclose should be threadsafe
      we need this to be a reliable detection.
      This is bug 20990. */
-  if (__builtin_expect (map->l_direct_opencount, 1) == 0)
+  if (__glibc_unlikely (map->l_direct_opencount == 0))
     {
       __rtld_lock_unlock_recursive (GL(dl_load_lock));
       _dl_signal_error (0, map->l_name, NULL, N_("shared object not open"));