MIPS/BFD: For n64 hold the number of internal relocs in `->reloc_count'

Revert parts of commit fee24f1c5bfe ("objdump improvements for mips
elf64"), <https://sourceware.org/ml/binutils/2003-03/msg00108.html>, and
make the `->reloc_count' member of `struct bfd_section' hold the actual
number of internal relocations stored in its `->relocation' vector.  To
do so adjust `mips_elf64_slurp_one_reloc_table' to set `->reloc_count'
to the actual number of internal relocations retrieved and discard
`mips_elf64_canonicalize_reloc', `mips_elf64_canonicalize_dynamic_reloc'
and their corresponding target macros.  Contrary to the description of
`mips_elf64_slurp_one_reloc_table', adjusted appropriately, this makes
generic relocation processing code happy and satisfies the "merge notes
section" binutils test case.

Add extra binutils test cases to expand the coverage of the generic
"merge notes section" test case, now passing with the n64 ABI, across
the MIPS o32, n32 and n64 ABIs regardless of the default ABI selected in
target configuration, and also to verify correctness of the relocations
produced.  Conversely, do not provide any additional test cases for the
original issue addressed with the commit referred:

- objdump would display only 1/3 of the total number of relocations,
  because it used the external relocation count, but each external
  relocation is brought in as 3 internal relocations.

as n64 ABI relocation processing with `objdump -r' and `objdump -R' is
already widely covered across the GAS and LD test suites.

	bfd/
	* elf64-mips.c (mips_elf64_canonicalize_reloc): Remove prototype
	and function.
	(mips_elf64_canonicalize_dynamic_reloc): Likewise.
	(mips_elf64_slurp_one_reloc_table): Set `reloc_count' to the
	actual number of internal relocations retrieved.  Adjust
	function description.
	(bfd_elf64_canonicalize_reloc): Remove macro.
	(bfd_elf64_canonicalize_dynamic_reloc): Likewise.

	binutils/
	* testsuite/binutils-all/mips/mips-note-2.d: New test.
	* testsuite/binutils-all/mips/mips-note-2r.d: New test.
	* testsuite/binutils-all/mips/mips-note-2-n32.d: New test.
	* testsuite/binutils-all/mips/mips-note-2-n64.d: New test.
	* testsuite/binutils-all/mips/mips-note-2r-n32.d: New test.
	* testsuite/binutils-all/mips/mips-note-2r-n64.d: New test.
	* testsuite/binutils-all/mips/mips.exp: Define `has_newabi'.
	Run the new tests.

2 files changed, 18 insertions, 75 deletions

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index 26b96f3..38462fe 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,14 @@
+2017-05-19  Maciej W. Rozycki  <macro@imgtec.com>
+
+	* elf64-mips.c (mips_elf64_canonicalize_reloc): Remove prototype
+	and function.
+	(mips_elf64_canonicalize_dynamic_reloc): Likewise.
+	(mips_elf64_slurp_one_reloc_table): Set `reloc_count' to the
+	actual number of internal relocations retrieved.  Adjust
+	function description.
+	(bfd_elf64_canonicalize_reloc): Remove macro.
+	(bfd_elf64_canonicalize_dynamic_reloc): Likewise.
+
 2017-05-19  Jose E. Marchesi  <jose.marchesi@oracle.com>
 
 	* archures.c (bfd_mach_sparc_v9m8): Define.
diff --git a/bfd/elf64-mips.c b/bfd/elf64-mips.c
index a66c319..e95db2c 100644
--- a/bfd/elf64-mips.c
+++ b/bfd/elf64-mips.c
@@ -88,12 +88,8 @@ static void mips_elf64_info_to_howto_rela
   (bfd *, arelent *, Elf_Internal_Rela *);
 static long mips_elf64_get_reloc_upper_bound
   (bfd *, asection *);
-static long mips_elf64_canonicalize_reloc
-  (bfd *, asection *, arelent **, asymbol **);
 static long mips_elf64_get_dynamic_reloc_upper_bound
   (bfd *);
-static long mips_elf64_canonicalize_dynamic_reloc
-  (bfd *, arelent **, asymbol **);
 static bfd_boolean mips_elf64_slurp_one_reloc_table
   (bfd *, asection *, Elf_Internal_Shdr *, bfd_size_type, arelent *,
    asymbol **, bfd_boolean);
@@ -3663,76 +3659,14 @@ mips_elf64_get_dynamic_reloc_upper_bound (bfd *abfd)
   return _bfd_elf_get_dynamic_reloc_upper_bound (abfd) * 3;
 }
 
-/* We must also copy more relocations than the corresponding functions
-   in elf.c would, so the two following functions are slightly
-   modified from elf.c, that multiply the external relocation count by
-   3 to obtain the internal relocation count.  */
-
-static long
-mips_elf64_canonicalize_reloc (bfd *abfd, sec_ptr section,
-			       arelent **relptr, asymbol **symbols)
-{
-  arelent *tblptr;
-  unsigned int i;
-  const struct elf_backend_data *bed = get_elf_backend_data (abfd);
-
-  if (! bed->s->slurp_reloc_table (abfd, section, symbols, FALSE))
-    return -1;
-
-  tblptr = section->relocation;
-  for (i = 0; i < section->reloc_count * 3; i++)
-    *relptr++ = tblptr++;
-
-  *relptr = NULL;
-
-  return section->reloc_count * 3;
-}
-
-static long
-mips_elf64_canonicalize_dynamic_reloc (bfd *abfd, arelent **storage,
-				       asymbol **syms)
-{
-  bfd_boolean (*slurp_relocs) (bfd *, asection *, asymbol **, bfd_boolean);
-  asection *s;
-  long ret;
-
-  if (elf_dynsymtab (abfd) == 0)
-    {
-      bfd_set_error (bfd_error_invalid_operation);
-      return -1;
-    }
-
-  slurp_relocs = get_elf_backend_data (abfd)->s->slurp_reloc_table;
-  ret = 0;
-  for (s = abfd->sections; s != NULL; s = s->next)
-    {
-      if (elf_section_data (s)->this_hdr.sh_link == elf_dynsymtab (abfd)
-	  && (elf_section_data (s)->this_hdr.sh_type == SHT_REL
-	      || elf_section_data (s)->this_hdr.sh_type == SHT_RELA))
-	{
-	  arelent *p;
-	  long count, i;
-
-	  if (! (*slurp_relocs) (abfd, s, syms, TRUE))
-	    return -1;
-	  count = s->size / elf_section_data (s)->this_hdr.sh_entsize * 3;
-	  p = s->relocation;
-	  for (i = 0; i < count; i++)
-	    *storage++ = p++;
-	  ret += count;
-	}
-    }
-
-  *storage = NULL;
-
-  return ret;
-}
-
 /* Read the relocations from one reloc section.  This is mostly copied
    from elfcode.h, except for the changes to expand one external
-   relocation to 3 internal ones.  We must unfortunately set
-   reloc_count to the number of external relocations, because a lot of
-   generic code seems to depend on this.  */
+   relocation to 3 internal ones.  To reduce processing effort we
+   could discard those R_MIPS_NONE relocations that occupy the second
+   and the third entry of a triplet, as `mips_elf64_write_rel' and
+   `mips_elf64_write_rela' recreate them in output automagically,
+   however that would also remove them from `objdump -r' output,
+   breaking a long-established tradition and likely confusing people.  */
 
 static bfd_boolean
 mips_elf64_slurp_one_reloc_table (bfd *abfd, asection *asect,
@@ -3885,7 +3819,7 @@ mips_elf64_slurp_one_reloc_table (bfd *abfd, asection *asect,
 	}
     }
 
-  asect->reloc_count += (relent - relents) / 3;
+  asect->reloc_count += relent - relents;
 
   if (allocated != NULL)
     free (allocated);
@@ -4504,9 +4438,7 @@ const struct elf_size_info mips_elf64_size_info =
 				_bfd_mips_elf_print_private_bfd_data
 
 #define bfd_elf64_get_reloc_upper_bound mips_elf64_get_reloc_upper_bound
-#define bfd_elf64_canonicalize_reloc mips_elf64_canonicalize_reloc
 #define bfd_elf64_get_dynamic_reloc_upper_bound mips_elf64_get_dynamic_reloc_upper_bound
-#define bfd_elf64_canonicalize_dynamic_reloc mips_elf64_canonicalize_dynamic_reloc
 #define bfd_elf64_mkobject		_bfd_mips_elf_mkobject
 
 /* The SGI style (n)64 NewABI.  */