commit ee67d69a3ff0eed25d98c5e97ed6c3ede8069edc

Author: Alan Modra <amodra@gmail.com>

Date:   Tue Oct 29 15:06:09 2013 +1030

    Add .abiversion related support for ELFv2

    Defines bits in ELF e_flags to differentiate ELFv2 objects from ELFv2,

    adds .abiversion directive to explicitly choose the ABI, and code to

    check and automatically select ABI.

    include/elf/

    	* ppc64.h (EF_PPC64_ABI): Define.

    bfd/

    	* elf64-ppc.c (abiversion, set_abiversion): New functions.

    	(ppc64_elf_get_synthetic_symtab): Handle ELFv2 objects without .opd.

    	(struct ppc_link_hash_table): Add opd_abi.

    	(ppc64_elf_check_relocs): Check no .opd with ELFv2.

    	(ppc64_elf_merge_private_bfd_data): New function.

    	(ppc64_elf_print_private_bfd_data): New function.

    	(ppc64_elf_tls_setup): Set htab->opd_abi.

    	(ppc64_elf_size_dynamic_sections): Don't emit OPD related dynamic

    	tags for ELFv2.

    	(ppc_build_one_stub): Use R_PPC64_IRELATIVE for ELFv2 ifunc.

    	(ppc64_elf_finish_dynamic_symbol): Likewise

    binutils/

    	* readelf.c (get_machine_flags): Display ABI version for EM_PPC64.

    gas/

    	* config/tc-ppc.c: Include elf/ppc64.h.

    	(ppc_abiversion): New variable.

    	(md_pseudo_table): Add .abiversion.

    	(ppc_elf_abiversion, ppc_elf_end): New functions.

    	* config/tc-ppc.h (md_end): Define.

Index: gdb-7.6.1/bfd/elf64-ppc.c

===================================================================

--- gdb-7.6.1.orig/bfd/elf64-ppc.c

+++ gdb-7.6.1/bfd/elf64-ppc.c

@@ -81,7 +81,8 @@ static bfd_vma opd_entry_value

 #define bfd_elf64_mkobject		      ppc64_elf_mkobject

 #define bfd_elf64_bfd_reloc_type_lookup	      ppc64_elf_reloc_type_lookup

 #define bfd_elf64_bfd_reloc_name_lookup	      ppc64_elf_reloc_name_lookup

-#define bfd_elf64_bfd_merge_private_bfd_data  _bfd_generic_verify_endian_match

+#define bfd_elf64_bfd_merge_private_bfd_data  ppc64_elf_merge_private_bfd_data

+#define bfd_elf64_bfd_print_private_bfd_data  ppc64_elf_print_private_bfd_data

 #define bfd_elf64_new_section_hook	      ppc64_elf_new_section_hook

 #define bfd_elf64_bfd_link_hash_table_create  ppc64_elf_link_hash_table_create

 #define bfd_elf64_bfd_link_hash_table_free    ppc64_elf_link_hash_table_free

@@ -2836,6 +2837,19 @@ get_opd_info (asection * sec)

     return &ppc64_elf_section_data (sec)->u.opd;

   return NULL;

 }

+

+static inline int

+abiversion (bfd *abfd)

+{

+  return elf_elfheader (abfd)->e_flags & EF_PPC64_ABI;

+}

+

+static inline void

+set_abiversion (bfd *abfd, int ver)

+{

+  elf_elfheader (abfd)->e_flags &= ~EF_PPC64_ABI;

+  elf_elfheader (abfd)->e_flags |= ver & EF_PPC64_ABI;

+}

 /* Parameters for the qsort hook.  */

 static bfd_boolean synthetic_relocatable;

@@ -2982,15 +2996,19 @@ ppc64_elf_get_synthetic_symtab (bfd *abf

   long count;

   char *names;

   long symcount, codesecsym, codesecsymend, secsymend, opdsymend;

-  asection *opd;

+  asection *opd = NULL;

   bfd_boolean relocatable = (abfd->flags & (EXEC_P | DYNAMIC)) == 0;

   asymbol **syms;

+  int abi = abiversion (abfd);

   *ret = NULL;

-  opd = bfd_get_section_by_name (abfd, ".opd");

-  if (opd == NULL)

-    return 0;

+  if (abi < 2)

+    {

+      opd = bfd_get_section_by_name (abfd, ".opd");

+      if (opd == NULL && abi == 1)

+	return 0;

+    }

   symcount = static_count;

   if (!relocatable)

@@ -3159,20 +3177,18 @@ ppc64_elf_get_synthetic_symtab (bfd *abf

   else

     {

       bfd_boolean (*slurp_relocs) (bfd *, asection *, asymbol **, bfd_boolean);

-      bfd_byte *contents;

+      bfd_byte *contents = NULL;

       size_t size;

       long plt_count = 0;

       bfd_vma glink_vma = 0, resolv_vma = 0;

       asection *dynamic, *glink = NULL, *relplt = NULL;

       arelent *p;

-      if (!bfd_malloc_and_get_section (abfd, opd, &contents))

+      if (opd != NULL && !bfd_malloc_and_get_section (abfd, opd, &contents))

 	{

+	free_contents_and_exit:

 	  if (contents)

-	    {

-	    free_contents_and_exit:

-	      free (contents);

-	    }

+	    free (contents);

 	  count = -1;

 	  goto done;

 	}

@@ -3772,6 +3788,9 @@ struct ppc_link_hash_table

   /* Alignment of PLT call stubs.  */

   unsigned int plt_stub_align:4;

+  /* Set if we're linking code with function descriptors.  */

+  unsigned int opd_abi:1;

+

   /* Set if PLT call stubs should load r11.  */

   unsigned int plt_static_chain:1;

@@ -4959,6 +4978,15 @@ ppc64_elf_check_relocs (bfd *abfd, struc

 	 information about the associated function section.  */

       bfd_size_type amt;

+      if (abiversion (abfd) == 0)

+	set_abiversion (abfd, 1);

+      else if (abiversion (abfd) == 2)

+	{

+	  info->callbacks->einfo (_("%P: .opd not allowed in ABI version %d\n"),

+				  abiversion (abfd));

+	  bfd_set_error (bfd_error_bad_value);

+	  return FALSE;

+	}

       amt = sec->size * sizeof (*opd_sym_map) / 8;

       opd_sym_map = bfd_zalloc (abfd, amt);

       if (opd_sym_map == NULL)

@@ -5518,6 +5546,78 @@ ppc64_elf_check_relocs (bfd *abfd, struc

   return TRUE;

 }

+/* Merge backend specific data from an object file to the output

+   object file when linking.  */

+

+static bfd_boolean

+ppc64_elf_merge_private_bfd_data (bfd *ibfd, bfd *obfd)

+{

+  unsigned long iflags, oflags;

+

+  if ((ibfd->flags & BFD_LINKER_CREATED) != 0)

+    return TRUE;

+

+  if (!is_ppc64_elf (ibfd) || !is_ppc64_elf (obfd))

+    return TRUE;

+

+  if (!_bfd_generic_verify_endian_match (ibfd, obfd))

+    return FALSE;

+

+  iflags = elf_elfheader (ibfd)->e_flags;

+  oflags = elf_elfheader (obfd)->e_flags;

+

+  if (!elf_flags_init (obfd) || oflags == 0)

+    {

+      elf_flags_init (obfd) = TRUE;

+      elf_elfheader (obfd)->e_flags = iflags;

+    }

+  else if (iflags == oflags || iflags == 0)

+    ;

+  else if (iflags & ~EF_PPC64_ABI)

+    {

+      (*_bfd_error_handler)

+	(_("%B uses unknown e_flags 0x%lx"), ibfd, iflags);

+      bfd_set_error (bfd_error_bad_value);

+      return FALSE;

+    }

+  else

+    {

+      (*_bfd_error_handler)

+	(_("%B: ABI version %ld is not compatible with ABI version %ld output"),

+	 ibfd, iflags, oflags);

+      bfd_set_error (bfd_error_bad_value);

+      return FALSE;

+    }

+

+  /* Merge Tag_compatibility attributes and any common GNU ones.  */

+  _bfd_elf_merge_object_attributes (ibfd, obfd);

+

+  return TRUE;

+}

+

+static bfd_boolean

+ppc64_elf_print_private_bfd_data (bfd *abfd, void *ptr)

+{

+  /* Print normal ELF private data.  */

+  _bfd_elf_print_private_bfd_data (abfd, ptr);

+

+  if (elf_elfheader (abfd)->e_flags != 0)

+    {

+      FILE *file = ptr;

+

+      /* xgettext:c-format */

+      fprintf (file, _("private flags = 0x%lx:"),

+	       elf_elfheader (abfd)->e_flags);

+

+      if ((elf_elfheader (abfd)->e_flags & EF_PPC64_ABI) != 0)

+	fprintf (file, _(" [abiv%ld]"),

+		 elf_elfheader (abfd)->e_flags & EF_PPC64_ABI);

+      fputc ('\n', file);

+    }

+

+  return TRUE;

+}

+

 /* OFFSET in OPD_SEC specifies a function descriptor.  Return the address

    of the code entry point, and its section.  */

@@ -7504,6 +7604,9 @@ ppc64_elf_tls_setup (struct bfd_link_inf

   if (htab == NULL)

     return NULL;

+  if (abiversion (info->output_bfd) == 1)

+    htab->opd_abi = 1;

+

   if (*no_multi_toc)

     htab->do_multi_toc = 0;

   else if (!htab->do_multi_toc)

@@ -9127,7 +9230,7 @@ readonly_dynrelocs (struct elf_link_hash

 /* Set the sizes of the dynamic sections.  */

 static bfd_boolean

-ppc64_elf_size_dynamic_sections (bfd *output_bfd ATTRIBUTE_UNUSED,

+ppc64_elf_size_dynamic_sections (bfd *output_bfd,

 				 struct bfd_link_info *info)

 {

   struct ppc_link_hash_table *htab;

@@ -9439,7 +9542,7 @@ ppc64_elf_size_dynamic_sections (bfd *ou

 	    return FALSE;

 	}

-      if (NO_OPD_RELOCS)

+      if (NO_OPD_RELOCS && abiversion (output_bfd) <= 1)

 	{

 	  if (!add_dynamic_entry (DT_PPC64_OPD, 0)

 	      || !add_dynamic_entry (DT_PPC64_OPDSZ, 0))

@@ -10202,7 +10305,10 @@ ppc_build_one_stub (struct bfd_hash_entr

 	  bfd_byte *rl;

 	  rela.r_offset = dest;

-	  rela.r_info = ELF64_R_INFO (0, R_PPC64_JMP_IREL);

+	  if (htab->opd_abi)

+	    rela.r_info = ELF64_R_INFO (0, R_PPC64_JMP_IREL);

+	  else

+	    rela.r_info = ELF64_R_INFO (0, R_PPC64_IRELATIVE);

 	  rela.r_addend = (stub_entry->target_value

 			   + stub_entry->target_section->output_offset

 			   + stub_entry->target_section->output_section->vma);

@@ -14012,7 +14118,10 @@ ppc64_elf_finish_dynamic_symbol (bfd *ou

 	    rela.r_offset = (htab->iplt->output_section->vma

 			     + htab->iplt->output_offset

 			     + ent->plt.offset);

-	    rela.r_info = ELF64_R_INFO (0, R_PPC64_JMP_IREL);

+	    if (htab->opd_abi)

+	      rela.r_info = ELF64_R_INFO (0, R_PPC64_JMP_IREL);

+	    else

+	      rela.r_info = ELF64_R_INFO (0, R_PPC64_IRELATIVE);

 	    rela.r_addend = (h->root.u.def.value

 			     + h->root.u.def.section->output_offset

 			     + h->root.u.def.section->output_section->vma

--- a/include/elf/ppc64.h

+++ b/include/elf/ppc64.h

@@ -173,6 +173,13 @@ END_RELOC_NUMBERS (R_PPC64_max)

   (((R) >= R_PPC64_TLS && (R) <= R_PPC64_DTPREL16_HIGHESTA)		\

    || ((R) >= R_PPC64_TPREL16_HIGH && (R) <= R_PPC64_DTPREL16_HIGHA))

+

+/* e_flags bits specifying ABI.

+   1 for original function descriptor using ABI,

+   2 for revised ABI without function descriptors,

+   0 for unspecified or not using any features affected by the differences.  */

+#define EF_PPC64_ABI	3

+

 /* Specify the start of the .glink section.  */

 #define DT_PPC64_GLINK		DT_LOPROC