s390: Refactor ifunc resolvers due to false debuginfo.

This patch adjusts the s390 specific ifunc helper macros in ifunc-resolve.h to
use the common __ifunc macro, which uses gcc attribute ifunc to get rid of the
false debuginfo. Therefore the redirection construct is applied where needed.

Perhaps in future we can switch some of the internal symbols __GI_* from the
fallback variant to the ifunc function. But this change is not
straightforward due to a segmentation fault while linking libc.so with older
binutils on s390.

ChangeLog:

	[BZ #20478]
	* sysdeps/s390/multiarch/ifunc-resolve.h
	(s390_vx_libc_ifunc2, s390_libc_ifunc): Use __ifunc from libc-symbols.h
	to create ifunc symbols.
	(s390_vx_libc_ifunc_init, s390_vx_libc_ifunc_redirected
	, s390_vx_libc_ifunc2_redirected, s390_libc_ifunc_init): New define.
	* sysdeps/s390/multiarch/memchr.c: Redirect ifunced function in header
	for using it as type for ifunc function.
	* sysdeps/s390/multiarch/mempcpy.c: Likewise.
	* sysdeps/s390/multiarch/rawmemchr.c: Likewise.
	* sysdeps/s390/multiarch/stpcpy.c: Likewise.
	* sysdeps/s390/multiarch/stpncpy.c: Likewise.
	* sysdeps/s390/multiarch/strcat.c: Likewise.
	* sysdeps/s390/multiarch/strchr.c: Likewise.
	* sysdeps/s390/multiarch/strcmp.c: Likewise.
	* sysdeps/s390/multiarch/strcpy.c: Likewise.
	* sysdeps/s390/multiarch/strcspn.c: Likewise.
	* sysdeps/s390/multiarch/strlen.c: Likewise.
	* sysdeps/s390/multiarch/strncmp.c: Likewise.
	* sysdeps/s390/multiarch/strncpy.c: Likewise.
	* sysdeps/s390/multiarch/strnlen.c: Likewise.
	* sysdeps/s390/multiarch/strpbrk.c: Likewise.
	* sysdeps/s390/multiarch/strrchr.c: Likewise.
	* sysdeps/s390/multiarch/strspn.c: Likewise.
	* sysdeps/s390/multiarch/wcschr.c: Likewise.
	* sysdeps/s390/multiarch/wcscmp.c: Likewise.
	* sysdeps/s390/multiarch/wcspbrk.c: Likewise.
	* sysdeps/s390/multiarch/wcsspn.c: Likewise.
	* sysdeps/s390/multiarch/wmemchr.c: Likewise.
	* sysdeps/s390/multiarch/wmemset.c: Likewise.
	* sysdeps/s390/s390-32/multiarch/memcmp.c: Likewise.
	* sysdeps/s390/s390-32/multiarch/memcpy.c: Likewise.
	* sysdeps/s390/s390-32/multiarch/memset.c: Likewise.
	* sysdeps/s390/s390-64/multiarch/memcmp.c: Likewise.
	* sysdeps/s390/s390-64/multiarch/memcpy.c: Likewise.
	* sysdeps/s390/s390-64/multiarch/memset.c: Likewise.

3 files changed, 13 insertions, 4 deletions

diff --git a/sysdeps/s390/s390-32/multiarch/memcmp.c b/sysdeps/s390/s390-32/multiarch/memcmp.c
index 44f72dc8ca..453b1706f7 100644
--- a/sysdeps/s390/s390-32/multiarch/memcmp.c
+++ b/sysdeps/s390/s390-32/multiarch/memcmp.c
@@ -17,8 +17,11 @@
    <http://www.gnu.org/licenses/>.  */
 
 #if IS_IN (libc)
+# define memcmp __redirect_memcmp
+# include <string.h>
+# undef memcmp
 # include <ifunc-resolve.h>
 
-s390_libc_ifunc (memcmp)
-__asm__(".weak bcmp ; bcmp = memcmp");
+s390_libc_ifunc (__redirect_memcmp, __memcmp, memcmp)
+weak_alias (memcmp, bcmp);
 #endif
diff --git a/sysdeps/s390/s390-32/multiarch/memcpy.c b/sysdeps/s390/s390-32/multiarch/memcpy.c
index 2a98aa0b82..33e4bcdca2 100644
--- a/sysdeps/s390/s390-32/multiarch/memcpy.c
+++ b/sysdeps/s390/s390-32/multiarch/memcpy.c
@@ -18,7 +18,10 @@
 
 /* In the static lib memcpy is needed before the reloc is resolved.  */
 #if defined SHARED && IS_IN (libc)
+# define memcpy __redirect_memcpy
+# include <string.h>
+# undef memcpy
 # include <ifunc-resolve.h>
 
-s390_libc_ifunc (memcpy)
+s390_libc_ifunc (__redirect_memcpy, __memcpy, memcpy)
 #endif
diff --git a/sysdeps/s390/s390-32/multiarch/memset.c b/sysdeps/s390/s390-32/multiarch/memset.c
index 89b8102f2a..84ddedaf04 100644
--- a/sysdeps/s390/s390-32/multiarch/memset.c
+++ b/sysdeps/s390/s390-32/multiarch/memset.c
@@ -17,7 +17,10 @@
    <http://www.gnu.org/licenses/>.  */
 
 #if IS_IN (libc)
+# define memset __redirect_memset
+# include <string.h>
+# undef memset
 # include <ifunc-resolve.h>
 
-s390_libc_ifunc (memset)
+s390_libc_ifunc (__redirect_memset, __memset, memset)
 #endif