PowerPC64 dynamic symbol tweaks

In check_relocs, bfd_link_pic true means ld is producing a shared
library or a position independent executable.  !bfd_link_pic means a
fixed position (ie. static) executable since the relocatable linking
case is excluded.  So it is appropriate to continue using bfd_link_pic
when testing whether non-pcrelative relocations should be dynamic, and
!bfd_link_pic for the special case of ifunc in static executables.
However, -Bsymbolic shouldn't affect PIEs (they are executables so
none of their symbols should be overridden) and PIEs can support copy
relocations, thus bfd_link_executable should be used in those cases
rather than bfd_link_pic.

I've also removed the test of ELIMINATE_COPY_RELOCS in check_relocs.
We can sort out what to do regarding copy relocs later, which allows
the code in check_relocs to be simplified.

	* elf64-ppc.c (ppc64_elf_check_relocs): Use bfd_link_executable
	in choosing between different actions for shared library and
	non-shared library cases.  Delete ELIMINATE_COPY_RELOCS test.
	(dec_dynrel_count): Likewise.  Account for ifunc special case.
	(ppc64_elf_adjust_dynamic_symbol): Copy relocs are for executables,
	not non-pic.
	(allocate_dynrelocs): Comment fixes.  Delete ELIMINATE_COPY_RELOCS
	test.

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index 1da5d0d48c4c856e23231e7b1d3ab944ab0513c3..ac0296482b3247b705443fc6fb399ad563f86a0c 100644 (file)
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,14 @@
+2019-09-23  Alan Modra  <amodra@gmail.com>
+
+       * elf64-ppc.c (ppc64_elf_check_relocs): Use bfd_link_executable
+       in choosing between different actions for shared library and
+       non-shared library cases.  Delete ELIMINATE_COPY_RELOCS test.
+       (dec_dynrel_count): Likewise.  Account for ifunc special case.
+       (ppc64_elf_adjust_dynamic_symbol): Copy relocs are for executables,
+       not non-pic.
+       (allocate_dynrelocs): Comment fixes.  Delete ELIMINATE_COPY_RELOCS
+       test.
+
 2019-09-23  Alan Modra  <amodra@gmail.com>
 
        * Makefile.am (SOURCE_HFILES): Add many missing .h files.

diff --git a/bfd/elf64-ppc.c b/bfd/elf64-ppc.c
index ed8077586bb383beabd32cd85d49671d08925902..d5a46dbf21f55f1f7d3ae3a1efcd32ec19f99c4c 100644 (file)
--- a/bfd/elf64-ppc.c
+++ b/bfd/elf64-ppc.c
@@ -4836,7 +4836,7 @@ ppc64_elf_check_relocs (bfd *abfd, struct bfd_link_info *info,
        case R_PPC64_TOC16_HA:
        case R_PPC64_TOC16_LO_DS:
          sec->has_toc_reloc = 1;
-         if (h != NULL && !bfd_link_pic (info))
+         if (h != NULL && bfd_link_executable (info))
            {
              /* We may need a copy reloc.  */
              h->non_got_ref = 1;
@@ -5076,7 +5076,7 @@ ppc64_elf_check_relocs (bfd *abfd, struct bfd_link_info *info,
        case R_PPC64_UADDR32:
        case R_PPC64_UADDR64:
        case R_PPC64_TOC:
-         if (h != NULL && !bfd_link_pic (info))
+         if (h != NULL && bfd_link_executable (info))
            /* We may need a copy reloc.  */
            h->non_got_ref = 1;
 
@@ -5106,17 +5106,14 @@ ppc64_elf_check_relocs (bfd *abfd, struct bfd_link_info *info,
             dynamic library if we manage to avoid copy relocs for the
             symbol.  */
        dodyn:
-         if ((bfd_link_pic (info)
-              && (must_be_dyn_reloc (info, r_type)
-                  || (h != NULL
-                      && (!SYMBOLIC_BIND (info, h)
-                          || h->root.type == bfd_link_hash_defweak
-                          || !h->def_regular))))
-             || (ELIMINATE_COPY_RELOCS
-                 && !bfd_link_pic (info)
-                 && h != NULL
-                 && (h->root.type == bfd_link_hash_defweak
-                     || !h->def_regular))
+         if ((h != NULL
+              && (h->root.type == bfd_link_hash_defweak
+                  || !h->def_regular))
+             || (h != NULL
+                 && !bfd_link_executable (info)
+                 && !SYMBOLIC_BIND (info, h))
+             || (bfd_link_pic (info)
+                 && must_be_dyn_reloc (info, r_type))
              || (!bfd_link_pic (info)
                  && ifunc != NULL))
            {
@@ -6425,7 +6422,7 @@ ppc64_elf_adjust_dynamic_symbol (struct bfd_link_info *info,
      only references to the symbol are via the global offset table.
      For such cases we need not do anything here; the relocations will
      be handled correctly by relocate_section.  */
-  if (bfd_link_pic (info))
+  if (!bfd_link_executable (info))
     return TRUE;
 
   /* If there are no references to this symbol that do not use the
@@ -6904,17 +6901,18 @@ dec_dynrel_count (bfd_vma r_info,
        return FALSE;
     }
 
-  if ((bfd_link_pic (info)
-       && (must_be_dyn_reloc (info, r_type)
-          || (h != NULL
-              && (!SYMBOLIC_BIND (info, h)
-                  || h->root.type == bfd_link_hash_defweak
-                  || !h->def_regular))))
-      || (ELIMINATE_COPY_RELOCS
-         && !bfd_link_pic (info)
-         && h != NULL
-         && (h->root.type == bfd_link_hash_defweak
-             || !h->def_regular)))
+  if ((h != NULL
+       && (h->root.type == bfd_link_hash_defweak
+          || !h->def_regular))
+      || (h != NULL
+         && !bfd_link_executable (info)
+         && !SYMBOLIC_BIND (info, h))
+      || (bfd_link_pic (info)
+         && must_be_dyn_reloc (info, r_type))
+      || (!bfd_link_pic (info)
+         && (h != NULL
+             ? h->type == STT_GNU_IFUNC
+             : ELF_ST_TYPE (sym->st_info) == STT_GNU_IFUNC)))
     ;
   else
     return TRUE;
@@ -9403,7 +9401,8 @@ allocate_dynrelocs (struct elf_link_hash_entry *h, void *inf)
   for (gent = h->got.glist; gent != NULL; gent = gent->next)
     if (!gent->is_indirect)
       {
-       /* Make sure this symbol is output as a dynamic symbol.  */
+       /* Ensure we catch all the cases where this symbol should
+          be made dynamic.  */
        if (!ensure_undef_dynamic (info, h))
          return FALSE;
 
@@ -9438,7 +9437,6 @@ allocate_dynrelocs (struct elf_link_hash_entry *h, void *inf)
         be defined in regular objects.  For the normal shared case,
         discard space for relocs that have become local due to symbol
         visibility changes.  */
-
       if (bfd_link_pic (info))
        {
          /* Relocs that use pc_count are those that appear on a call
@@ -9463,24 +9461,27 @@ allocate_dynrelocs (struct elf_link_hash_entry *h, void *inf)
 
          if (eh->dyn_relocs != NULL)
            {
-             /* Make sure this symbol is output as a dynamic symbol.  */
+             /* Ensure we catch all the cases where this symbol
+                should be made dynamic.  */
              if (!ensure_undef_dynamic (info, h))
                return FALSE;
            }
        }
-      else if (ELIMINATE_COPY_RELOCS && h->type != STT_GNU_IFUNC)
+
+      /* For a fixed position executable, discard space for
+        relocs against symbols which are not dynamic.  */
+      else if (h->type != STT_GNU_IFUNC)
        {
-         /* For the non-pic case, discard space for relocs against
-            symbols which turn out to need copy relocs or are not
-            dynamic.  */
          if (h->dynamic_adjusted
              && !h->def_regular
              && !ELF_COMMON_DEF_P (h))
            {
-             /* Make sure this symbol is output as a dynamic symbol.  */
+             /* Ensure we catch all the cases where this symbol
+                should be made dynamic.  */
              if (!ensure_undef_dynamic (info, h))
                return FALSE;
 
+             /* But if that didn't work out, discard dynamic relocs.  */
              if (h->dynindx == -1)
                eh->dyn_relocs = NULL;
            }