* elf32-cris.c (cris_elf_relocate_section) <case R_CRIS_16_GOTPLT,

	R_CRIS_16_GOTPLT>: Also error if there's no PLT for a symbol
	not defined by the executable, or defined in a DSO.
	<eliding run-time relocation of .got>: Initialize GOT entry for a
	function symbol or ELF_LINK_HASH_NEEDS_PLT statically in an
	executable.
	(cris_elf_gc_sweep_hook): Improve fallthrough marking.
	(elf_cris_try_fold_plt_to_got): Improve head comment.  Do not fold
	a PLT reloc to GOT for an executable.
	(elf_cris_adjust_dynamic_symbol): Only fold a .got.plt entry with
	.got for a DSO and explain why.
	(elf_cris_discard_excess_program_dynamics): Also lose GOT-relocs
	and unreferenced symbols for which a PLT is defined.  Adjust
	dynamic-symbol pruning correspondingly, to make sure we don't lose
	a dynamic symbol also defined by a DSO.

1 files changed, 64 insertions, 25 deletions

diff --git a/bfd/elf32-cris.c b/bfd/elf32-cris.c
index 18f87f4..b851392 100644
--- a/bfd/elf32-cris.c
+++ b/bfd/elf32-cris.c
@@ -960,11 +960,25 @@ cris_elf_relocate_section (output_bfd, info, input_bfd, input_section,
 	     statically linking PIC code, or when using -Bsymbolic.  Check
 	     that we instead have a GOT entry as done for us by
 	     elf_cris_adjust_dynamic_symbol, and drop through into the
-	     ordinary GOT cases.  */
-	  if (h != NULL && h->got.offset == (bfd_vma) -1)
+	     ordinary GOT cases.  This must not happen for the
+	     executable, because any reference it does to a function
+	     that is satisfied by a DSO must generate a PLT.  We assume
+	     these call-specific relocs don't address non-functions.  */
+	  if (h != NULL
+	      && (h->got.offset == (bfd_vma) -1
+		  || (!info->shared
+		      && !((h->elf_link_hash_flags
+			    & ELF_LINK_HASH_DEF_REGULAR) != 0
+			   || ((h->elf_link_hash_flags
+				& ELF_LINK_HASH_DEF_DYNAMIC) == 0
+			      && h->root.type == bfd_link_hash_undefweak)))))
 	    {
 	      (*_bfd_error_handler)
-		(_("%s: No PLT nor GOT for relocation %s against symbol `%s' from %s section"),
+		((h->got.offset == (bfd_vma) -1)
+		 ? _("%s: No PLT nor GOT for relocation %s against\
+ symbol `%s' from %s section")
+		 : _("%s: No PLT for relocation %s against\
+ symbol `%s' from %s section"),
 		 bfd_archive_filename (input_bfd),
 		 cris_elf_howto_table[r_type].name,
 		 symname[0] != '\0' ? symname : _("[whose name is lost]"),
@@ -996,18 +1010,25 @@ cris_elf_relocate_section (output_bfd, info, input_bfd, input_section,
 
 		if (!elf_hash_table (info)->dynamic_sections_created
 		    || (! info->shared
-			&& (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR))
+			&& ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR)
+			    || h->type == STT_FUNC
+			    || (h->elf_link_hash_flags
+				& ELF_LINK_HASH_NEEDS_PLT)))
 		    || (info->shared
 			&& (info->symbolic || h->dynindx == -1)
 			&& (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR)))
 		  {
 		    /* This wasn't checked above for ! info->shared, but
-		       must hold there if we get here; the symbol must be
-		       defined in the regular program, or be undefweak.  */
+		       must hold there if we get here; the symbol must
+		       be defined in the regular program or be undefweak
+		       or be a function or otherwise need a PLT.  */
 		    BFD_ASSERT (!elf_hash_table (info)->dynamic_sections_created
 				|| info->shared
 				|| (h->elf_link_hash_flags
 				    & ELF_LINK_HASH_DEF_REGULAR) != 0
+				|| h->type == STT_FUNC
+				|| (h->elf_link_hash_flags
+				    & ELF_LINK_HASH_NEEDS_PLT)
 				|| h->root.type == bfd_link_hash_undefweak);
 
 		    /* This is actually a static link, or it is a
@@ -1511,12 +1532,15 @@ elf_cris_finish_dynamic_symbol (output_bfd, info, h, sym)
 	}
     }
 
-  /* We don't emit .got relocs for symbols that aren't in the
-     dynamic-symbols table for an ordinary program and are either defined
-     by the program or are undefined weak symbols.  */
+  /* For an ordinary program, we emit .got relocs only for symbols that
+     are in the dynamic-symbols table and are either defined by the
+     program or are undefined weak symbols, or are function symbols
+     where we do not output a PLT: the PLT reloc was output above and all
+     references to the function symbol are redirected to the PLT.  */
   if (h->got.offset != (bfd_vma) -1
       && (info->shared
 	  || (h->dynindx != -1
+	      && h->plt.offset == (bfd_vma) -1
 	      && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
 	      && h->root.type != bfd_link_hash_undefweak)))
     {
@@ -1838,13 +1862,12 @@ cris_elf_gc_sweep_hook (abfd, info, sec, relocs)
 	  r_symndx = ELF32_R_SYM (rel->r_info);
 	  if (r_symndx < symtab_hdr->sh_info)
 	    goto local_got_reloc;
-
+	  /* Fall through.  */
 	case R_CRIS_32_PLT_GOTREL:
 	  /* FIXME: We don't garbage-collect away the .got section.  */
 	  if (local_got_refcounts != NULL)
 	    local_got_refcounts[-1]--;
 	  /* Fall through.  */
-
 	case R_CRIS_8_PCREL:
 	case R_CRIS_16_PCREL:
 	case R_CRIS_32_PCREL:
@@ -1929,16 +1952,22 @@ elf_cris_adjust_gotplt_to_got (h, p)
    want to do this:
 
    - When all PLT references are GOTPLT references, and there are GOT
-     references.  We don't have to generate a PLT at all.
+     references, and this is not the executable.  We don't have to
+     generate a PLT at all.
 
-   - When there are both (ordinary) PLT references and GOT references.
+   - When there are both (ordinary) PLT references and GOT references,
+     and this isn't the executable.
      We want to make the PLT reference use the ordinary GOT entry rather
-     than a run-time dynamically resolved GOTPLT entry (since the GOT
-     entry will have to be resolved at startup anyway).
+     than R_CRIS_JUMP_SLOT, a run-time dynamically resolved GOTPLT entry,
+     since the GOT entry will have to be resolved at startup anyway.
 
    Though the latter case is handled when room for the PLT is allocated,
    not here.
 
+   By folding into the GOT, we may need a round-trip to a PLT in the
+   executable for calls, a loss in performance.  Still, losing a
+   reloc is a win in size and at least in start-up time.
+
    Note that this function is called before symbols are forced local by
    version scripts.  The differing cases are handled by
    elf_cris_hide_symbol.  */
@@ -2045,10 +2074,14 @@ elf_cris_adjust_dynamic_symbol (info, h)
 					   info);
 	}
 
-      /* If there are only GOT references and GOTPLT references to this
-	 PLT entry, get rid of the PLT.  */
-      if (! elf_cris_try_fold_plt_to_got ((struct elf_cris_link_hash_entry *)
-					  h, info))
+      /* If we had a R_CRIS_GLOB_DAT that didn't have to point to a PLT;
+	 where a pointer-equivalent symbol was unimportant (i.e. more
+	 like R_CRIS_JUMP_SLOT after symbol evaluation) we could get rid
+	 of the PLT.  We can't for the executable, because the GOT
+	 entries will point to the PLT there (and be constant).  */
+      if (info->shared
+	  && !elf_cris_try_fold_plt_to_got ((struct elf_cris_link_hash_entry*)
+					    h, info))
 	return FALSE;
 
       /* GC or folding may have rendered this entry unused.  */
@@ -2086,8 +2119,11 @@ elf_cris_adjust_dynamic_symbol (info, h)
 
       /* If there's already a GOT entry, use that, not a .got.plt.  A
 	 GOT field still has a reference count when we get here; it's
-	 not yet changed to an offset.  */
-      if (h->got.refcount > 0)
+	 not yet changed to an offset.  We can't do this for an
+	 executable, because then the reloc associated with the PLT
+	 would get a non-PLT reloc pointing to the PLT.  FIXME: Move
+	 this to elf_cris_try_fold_plt_to_got.  */
+      if (info->shared && h->got.refcount > 0)
 	{
 	  h->got.refcount += h->plt.refcount;
 
@@ -2860,9 +2896,11 @@ elf_cris_discard_excess_program_dynamics (h, inf)
 
   /* If we're not creating a shared library and have a symbol which is
      referred to by .got references, but the symbol is defined locally,
-     (or rather, not not defined by a DSO) then lose the reloc for the
-     .got (don't allocate room for it).  */
-  if ((h->root.elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0)
+     (or rather, not defined by a DSO) then lose the reloc for the .got
+     (don't allocate room for it).  Likewise for relocs for something
+     for which we create a PLT.  */
+  if ((h->root.elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
+      || h->root.plt.refcount > 0)
     {
       if (h->root.got.refcount > 0
 	  /* The size of this section is only valid and in sync with the
@@ -2888,7 +2926,8 @@ elf_cris_discard_excess_program_dynamics (h, inf)
 	 introduce new problems.  Of course we don't do this if we're
 	 exporting all dynamic symbols.  */
       if (! info->export_dynamic
-	  && (h->root.elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) == 0)
+	  && (h->root.elf_link_hash_flags
+	      & (ELF_LINK_HASH_DEF_DYNAMIC|ELF_LINK_HASH_REF_DYNAMIC)) == 0)
 	{
 	  h->root.dynindx = -1;
 	  _bfd_elf_strtab_delref (elf_hash_table (info)->dynstr,