S/390: Add support for STT_GNU_IFUNC symbols.

Add support for STT_GNU_IFUNC symbols and the new R_390_IRELATIVE
relocation.  Provide optimized version of memcpy, memset, and memcmp
for z10 and z196.

1 files changed, 52 insertions, 0 deletions

diff --git a/sysdeps/s390/dl-irel.h b/sysdeps/s390/dl-irel.h
new file mode 100644
index 0000000000..bc1a10e506
--- /dev/null
+++ b/sysdeps/s390/dl-irel.h
@@ -0,0 +1,52 @@
+/* Machine-dependent ELF indirect relocation inline functions.
+   Version for S/390 32 and 64 bit.
+   Copyright (C) 2012 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef _DL_IREL_H
+#define _DL_IREL_H
+
+#include <stdio.h>
+#include <unistd.h>
+#include <ldsodefs.h>
+
+#define ELF_MACHINE_IRELA	1
+
+static inline ElfW(Addr)
+__attribute ((always_inline))
+elf_ifunc_invoke (ElfW(Addr) addr)
+{
+  return ((ElfW(Addr) (*) (unsigned long int)) (addr)) (GLRO(dl_hwcap));
+}
+
+static inline void
+__attribute ((always_inline))
+elf_irela (const ElfW(Rela) *reloc)
+{
+  ElfW(Addr) *const reloc_addr = (void *) reloc->r_offset;
+  const unsigned long int r_type = ELFW(R_TYPE) (reloc->r_info);
+
+  if (__builtin_expect (r_type == R_390_IRELATIVE, 1))
+    {
+      ElfW(Addr) value = elf_ifunc_invoke(reloc->r_addend);
+      *reloc_addr = value;
+    }
+  else
+    __libc_fatal ("unexpected reloc type in static binary");
+}
+
+#endif /* dl-irel.h */