S/390: ifunc: Redirect local function calls to the IPLT.

bfd/ChangeLog:

	* elf32-s390.c (elf_s390_check_relocs): Set the non_got_ref marker
	only when linking an executable.
	(elf_s390_relocate_section): Redirect PC-relative relocs to a IPLT
	slot.
	* elf64-s390.c (elf_s390_check_relocs): Set the non_got_ref marker
	only when linking an executable.
	(elf_s390_relocate_section): Redirect PC-relative relocs to a IPLT
	slot.

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index b7f42cd..3956966 100644 (file)
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,5 +1,16 @@
 2015-10-22  Andreas Krebbel  <krebbel@linux.vnet.ibm.com>
 
+       * elf32-s390.c (elf_s390_check_relocs): Set the non_got_ref marker
+       only when linking an executable.
+       (elf_s390_relocate_section): Redirect PC-relative relocs to a IPLT
+       slot.
+       * elf64-s390.c (elf_s390_check_relocs): Set the non_got_ref marker
+       only when linking an executable.
+       (elf_s390_relocate_section): Redirect PC-relative relocs to a IPLT
+       slot.
+
+2015-10-22  Andreas Krebbel  <krebbel@linux.vnet.ibm.com>
+
        * elf32-s390.c (elf_s390_adjust_dynamic_symbol): Set the PLT
        reference counters for local IFUNC calls.
        * elf64-s390.c (elf_s390_adjust_dynamic_symbol): Likewise.

diff --git a/bfd/elf32-s390.c b/bfd/elf32-s390.c
index d154fb7..3fad6b3 100644 (file)
--- a/bfd/elf32-s390.c
+++ b/bfd/elf32-s390.c
@@ -1272,7 +1272,7 @@ elf_s390_check_relocs (bfd *abfd,
        case R_390_PC24DBL:
        case R_390_PC32DBL:
        case R_390_PC32:
-         if (h != NULL)
+         if (h != NULL && bfd_link_executable (info))
            {
              /* If this reloc is in a read-only section, we might
                 need a copy reloc.  We can't check reliably at this
@@ -2776,9 +2776,6 @@ elf_s390_relocate_section (bfd *output_bfd,
          unresolved_reloc = FALSE;
          break;
 
-       case R_390_8:
-       case R_390_16:
-       case R_390_32:
        case R_390_PC16:
        case R_390_PC12DBL:
        case R_390_PC16DBL:
@@ -2787,6 +2784,29 @@ elf_s390_relocate_section (bfd *output_bfd,
        case R_390_PC32:
          if (h != NULL
              && s390_is_ifunc_symbol_p (h)
+             && h->def_regular
+             && !bfd_link_executable (info))
+           {
+             /* This will not work our if the function does not
+                happen to set up the GOT pointer for some other
+                reason.  31 bit PLT entries require r12 to hold the
+                GOT pointer.
+                FIXME: Implement an errorcheck.
+                NOTE: It will work when brasl is not available
+                (e.g. with -m31 -march=g5) since a local function
+                call then does use GOTOFF which implies r12 being set
+                up.  */
+             relocation = (htab->elf.iplt->output_section->vma
+                           + htab->elf.iplt->output_offset
+                           + h ->plt.offset);
+             goto do_relocation;
+           }
+
+       case R_390_8:
+       case R_390_16:
+       case R_390_32:
+         if (h != NULL
+             && s390_is_ifunc_symbol_p (h)
              && h->def_regular)
            {
              if (!bfd_link_pic (info) || !h->non_got_ref)

diff --git a/bfd/elf64-s390.c b/bfd/elf64-s390.c
index 2b62271..bd9c082 100644 (file)
--- a/bfd/elf64-s390.c
+++ b/bfd/elf64-s390.c
@@ -1205,7 +1205,7 @@ elf_s390_check_relocs (bfd *abfd,
        case R_390_PC32:
        case R_390_PC32DBL:
        case R_390_PC64:
-         if (h != NULL)
+         if (h != NULL && bfd_link_executable (info))
            {
              /* If this reloc is in a read-only section, we might
                 need a copy reloc.  We can't check reliably at this
@@ -2718,10 +2718,6 @@ elf_s390_relocate_section (bfd *output_bfd,
          unresolved_reloc = FALSE;
          break;
 
-       case R_390_8:
-       case R_390_16:
-       case R_390_32:
-       case R_390_64:
        case R_390_PC16:
        case R_390_PC12DBL:
        case R_390_PC16DBL:
@@ -2729,6 +2725,24 @@ elf_s390_relocate_section (bfd *output_bfd,
        case R_390_PC32:
        case R_390_PC32DBL:
        case R_390_PC64:
+         /* The target of these relocs are instruction operands
+            residing in read-only sections.  We cannot emit a runtime
+            reloc for it.  */
+         if (h != NULL
+             && s390_is_ifunc_symbol_p (h)
+             && h->def_regular
+             && bfd_link_pic (info))
+           {
+             relocation = (htab->elf.iplt->output_section->vma
+                           + htab->elf.iplt->output_offset
+                           + h->plt.offset);
+             goto do_relocation;
+           }
+
+       case R_390_8:
+       case R_390_16:
+       case R_390_32:
+       case R_390_64:
 
          if (h != NULL
              && s390_is_ifunc_symbol_p (h)