Convert __builtin_expect to __glibc_(un)likely throughout elf/.zack/no-cancellation-in-ldso-2

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, 7 insertions, 7 deletions

diff --git a/elf/dl-runtime.c b/elf/dl-runtime.c
index 63bbc89776..17d691ceb9 100644
--- a/elf/dl-runtime.c
+++ b/elf/dl-runtime.c
@@ -81,7 +81,7 @@ _dl_fixup (
 
    /* Look up the target symbol.  If the normal lookup rules are not
       used don't look in the global scope.  */
-  if (__builtin_expect (ELFW(ST_VISIBILITY) (sym->st_other), 0) == 0)
+  if (__glibc_likely (ELFW(ST_VISIBILITY) (sym->st_other) == 0))
     {
       const struct r_found_version *version = NULL;
 
@@ -138,7 +138,7 @@ _dl_fixup (
   value = elf_machine_plt_value (l, reloc, value);
 
   if (sym != NULL
-      && __builtin_expect (ELFW(ST_TYPE) (sym->st_info) == STT_GNU_IFUNC, 0))
+      && __glibc_unlikely (ELFW(ST_TYPE) (sym->st_info) == STT_GNU_IFUNC))
     value = elf_ifunc_invoke (DL_FIXUP_VALUE_ADDR (value));
 
   /* Finally, fix up the plt itself.  */
@@ -204,7 +204,7 @@ _dl_profile_fixup (
 
       /* Look up the target symbol.  If the symbol is marked STV_PROTECTED
 	 don't look in the global scope.  */
-      if (__builtin_expect (ELFW(ST_VISIBILITY) (refsym->st_other), 0) == 0)
+      if (__glibc_likely (ELFW(ST_VISIBILITY) (refsym->st_other) == 0))
 	{
 	  const struct r_found_version *version = NULL;
 
@@ -243,8 +243,8 @@ _dl_profile_fixup (
 				       SYMBOL_ADDRESS (result, defsym, false));
 
 	  if (defsym != NULL
-	      && __builtin_expect (ELFW(ST_TYPE) (defsym->st_info)
-				   == STT_GNU_IFUNC, 0))
+	      && __glibc_unlikely (ELFW(ST_TYPE) (defsym->st_info)
+				   == STT_GNU_IFUNC))
 	    value = elf_ifunc_invoke (DL_FIXUP_VALUE_ADDR (value));
 	}
       else
@@ -253,8 +253,8 @@ _dl_profile_fixup (
 	     address) is also known.  */
 	  value = DL_FIXUP_MAKE_VALUE (l, SYMBOL_ADDRESS (l, refsym, true));
 
-	  if (__builtin_expect (ELFW(ST_TYPE) (refsym->st_info)
-				== STT_GNU_IFUNC, 0))
+	  if (__glibc_unlikely (ELFW(ST_TYPE) (refsym->st_info)
+				== STT_GNU_IFUNC))
 	    value = elf_ifunc_invoke (DL_FIXUP_VALUE_ADDR (value));
 
 	  result = l;