ELF: Call check_relocs after opening all inputs

For all ELF targers, call check_relocs after opening all inputs and
garbage collection.  Since the symbol resolution is known, check_relocs
can be simplified.  Also garbage collection doesn't need to undo what
check_relocs has done for symbols which have been garbage collected.
Since ELF targets never see the removed sections, gc_sweep_hook can be
removed from elf_backend_data and we can avoid GOT/PLT with garbage
collection now.

Set link_info.check_relocs_after_open_input to TRUE for all linker
targets which use ELF linker and update garbage collection tests to
remove unused GOT section.

ldemul_after_check_relocs is added for powerpc to support --secure-plt,
--bss-plt and --sdata-got.

Tested natively without regressions on i686, x86-64 and x32.  Tested
cross binutils on x86-64 without regressions for aarch64-linux,
alpha-linux, arm-linux, bfin-elf, cr16-elf, cris-elf, crx-elf, frv-linux,
hppa64-linux, hppa-linux, ia64-linux, lm32-elf, m32r-elf, m68k-linux,
mcore-elf, metag-elf, microblaze-linux, mips-linux, mmix, mn10300-elf,
nds32le-linux, nios2-linux, or1k-elf, powerpc64-linux, powerpc-linux,
riscv32-linux, riscv64-linux, s390-linux, s390x-linux, score-elf,
sh3-linux, sparc64-linux, sparc-linux, tic6x-elf, tilegx-linux,
tilepro-linux, vax-linux, x86_64-mingw32 and xtensa-linux.

bfd/

	* elf-bfd.h (elf_backend_data): Remove gc_sweep_hook.
	* elf32-arm.c (elf32_arm_gc_sweep_hook): Removed.
	(elf_backend_gc_sweep_hook): Likewise.
	* elf32-bfin.c (bfin_gc_sweep_hook): Likewise.
	(bfinfdpic_gc_sweep_hook): Likewise.
	(elf_backend_gc_sweep_hook): Likewise.
	* elf32-cr16.c (elf32_cr16_gc_sweep_hook): Likewise.
	(elf_backend_gc_sweep_hook): Likewise.
	* elf32-cris.c (cris_elf_gc_sweep_hook): Likewise.
	(elf_backend_gc_sweep_hook): Likewise.
	* elf32-hppa.c (elf32_hppa_gc_sweep_hook): Likewise.
	(elf_backend_gc_sweep_hook): Likewise.
	* elf32-lm32.c (lm32_elf_gc_sweep_hook): Likewise.
	(elf_backend_gc_sweep_hook): Likewise.
	* elf32-m32r.c (m32r_elf_gc_sweep_hook): Likewise.
	(elf_backend_gc_sweep_hook): Likewise.
	* elf32-m68k.c (elf_m68k_got_entry): Remove elf_m68k_gc_sweep_hook
	from comments.
	(elf_m68k_remove_got_entry_type): Removed.
	(elf_m68k_find_got_entry_ptr): Likewise.
	(elf_m68k_remove_got_entry): Likewise.
	(elf_m68k_gc_sweep_hook): Likewise.
	(elf_backend_gc_sweep_hook): Likewise.
	* elf32-mcore.c (mcore_elf_gc_sweep_hook): Likewise.
	(elf_backend_gc_sweep_hook): Likewise.
	* elf32-metag.c (elf_metag_gc_sweep_hook): Likewise.
	(elf_backend_gc_sweep_hook): Likewise.
	* elf32-microblaze.c (elf_backend_gc_sweep_hook): Likewise.
	(elf_backend_gc_sweep_hook): Likewise.
	* elf32-mips.c (elf_backend_gc_sweep_hook): Likewise.
	(elf_backend_gc_sweep_hook): Likewise.
	* elf32-nds32.c (nds32_elf_gc_sweep_hook): Likewise.
	(elf_backend_gc_sweep_hook): Likewise.
	* elf32-nios2.c (nios2_elf32_gc_sweep_hook): Likewise.
	(elf_backend_gc_sweep_hook): Likewise.
	* elf32-or1k.c (or1k_elf_gc_sweep_hook): Likewise.
	(elf_backend_gc_sweep_hook): Likewise.
	* elf32-ppc.c (ppc_elf_gc_sweep_hook): Likewise.
	(elf_backend_gc_sweep_hook): Likewise.
	* elf32-s390.c (elf_s390_gc_sweep_hook): Likewise.
	(elf_backend_gc_sweep_hook): Likewise.
	* elf32-sparc.c (elf_backend_gc_sweep_hook): Likewise.
	* elf32-tic6x.c (elf32_tic6x_gc_sweep_hook): Likewise.
	(elf_backend_gc_sweep_hook): Likewise.
	* elf32-tilegx.c (elf_backend_gc_sweep_hook): Likewise.
	* elf32-tilepro.c (tilepro_elf_gc_sweep_hook): Likewise.
	(elf_backend_gc_sweep_hook): Likewise.
	* elf32-vax.c (elf_vax_gc_sweep_hook): Likewise.
	(elf_backend_gc_sweep_hook): Likewise.
	* elf32-xtensa.c (elf_xtensa_gc_sweep_hook): Likewise.
	(elf_backend_gc_sweep_hook): Likewise.
	* elf64-alpha.c (elf64_alpha_gc_sweep_hook): Likewise.
	(elf_backend_gc_sweep_hook): Likewise.
	* elf64-mips.c (elf_backend_gc_sweep_hook): Likewise.
	* elf64-mmix.c (mmix_elf_gc_sweep_hook): Likewise.
	(elf_backend_gc_sweep_hook): Likewise.
	* elf64-ppc.c (elf_backend_gc_sweep_hook): Likewise.
	(ppc64_elf_gc_sweep_hook): Likewise.
	* elf64-s390.c (elf_s390_gc_sweep_hook): Likewise.
	(elf_backend_gc_sweep_hook): Likewise.
	* elf64-sparc.c (elf_backend_gc_sweep_hook): Likewise.
	* elf64-tilegx.c (elf_backend_gc_sweep_hook): Likewise.
	* elflink.c (elf_link_add_object_symbols): Don't call
	_bfd_elf_link_check_relocs here.
	(gc_sweep_hook_fn): Removed.
	(elf_gc_sweep): Remove gc_sweep_hook.
	* elfnn-aarch64.c (elfNN_aarch64_gc_sweep_hook): Removed.
	(elf_backend_gc_sweep_hook): Likewise.
	* elfnn-riscv.c (riscv_elf_gc_sweep_hook): Likewise.
	(elf_backend_gc_sweep_hook): Likewise.
	* elfxx-mips.c (_bfd_mips_elf_gc_sweep_hook): Likewise.
	* elfxx-mips.h (_bfd_mips_elf_gc_sweep_hook): Likewise.
	(elf_backend_gc_sweep_hook): Likewise.
	* elfxx-sparc.c (_bfd_sparc_elf_gc_sweep_hook): Likewise.
	* elfxx-sparc.h (_bfd_sparc_elf_gc_sweep_hook): Likewise.
	* elfxx-target.h (elf_backend_gc_sweep_hook): Likewise.
	(elfNN_bed): Remove elf_backend_gc_sweep_hook.
	* elfxx-tilegx.c (tilegx_elf_gc_sweep_hook): Removed.
	* elfxx-tilegx.h (tilegx_elf_gc_sweep_hook): Likewise.

ld/

	* emulparams/elf32_x86_64.sh (CHECK_RELOCS_AFTER_OPEN_INPUT):
	Removed.
	* emulparams/elf_i386_be.sh (CHECK_RELOCS_AFTER_OPEN_INPUT):
	Likewise.
	* emulparams/elf_i386_chaos.sh (CHECK_RELOCS_AFTER_OPEN_INPUT):
	Likewise.
	* emulparams/elf_i386_ldso.sh (CHECK_RELOCS_AFTER_OPEN_INPUT):
	Likewise.
	* emulparams/elf_i386_vxworks.sh (CHECK_RELOCS_AFTER_OPEN_INPUT):
	Likewise.
	* emulparams/elf_iamcu.sh (CHECK_RELOCS_AFTER_OPEN_INPUT):
	Likewise.
	* emulparams/elf_k1om.sh (CHECK_RELOCS_AFTER_OPEN_INPUT):
	Likewise.
	* emulparams/elf_l1om.sh (CHECK_RELOCS_AFTER_OPEN_INPUT):
	Likewise.
	* emulparams/elf_x86_64.sh (CHECK_RELOCS_AFTER_OPEN_INPUT):
	Likewise.
	* emulparams/i386lynx.sh (CHECK_RELOCS_AFTER_OPEN_INPUT):
	Likewise.
	* emulparams/i386moss.sh (CHECK_RELOCS_AFTER_OPEN_INPUT):
	Likewise.
	* emulparams/i386nto.sh (CHECK_RELOCS_AFTER_OPEN_INPUT):
	Likewise.
	* emulparams/i386nw.sh (CHECK_RELOCS_AFTER_OPEN_INPUT):
	Likewise.
	* emulparams/shelf.sh (CHECK_RELOCS_AFTER_OPEN_INPUT):
	Likewise.
	* emulparams/shelf32.sh (CHECK_RELOCS_AFTER_OPEN_INPUT):
	Likewise.
	* emulparams/shelf_nto.sh (CHECK_RELOCS_AFTER_OPEN_INPUT):
	Likewise.
	* emulparams/shelf_vxworks.sh (CHECK_RELOCS_AFTER_OPEN_INPUT):
	Likewise.
	* emulparams/shlelf32_linux.sh (CHECK_RELOCS_AFTER_OPEN_INPUT):
	Likewise.
	* emulparams/shlelf_linux.sh (CHECK_RELOCS_AFTER_OPEN_INPUT):
	Likewise.
	* emulparams/shlelf_nto.sh (CHECK_RELOCS_AFTER_OPEN_INPUT):
	Likewise.
	* emultempl/aarch64elf.em (gld${EMULATION_NAME}_before_parse):
	Set link_info.check_relocs_after_open_input to TRUE.
	* emultempl/armelf.em (gld${EMULATION_NAME}_before_parse):
	Likewise.
	* emultempl/scoreelf.em (gld${EMULATION_NAME}_before_parse):
	Likewise.
	* emultempl/aix.em (ld_${EMULATION_NAME}_emulation): Add
	after_parse_default.
	* emultempl/armcoff.em (ld_${EMULATION_NAME}_emulation): Likewise.
	* emultempl/beos.em (ld_${EMULATION_NAME}_emulation): Likewise.
	* emultempl/generic.em (ld_${EMULATION_NAME}_emulation): Likewise.
	* emultempl/gld960.em (ld_${EMULATION_NAME}_emulation): Likewise.
	* emultempl/gld960c.em (ld_${EMULATION_NAME}_emulation): Likewise.
	* emultempl/lnk960.em (ld_${EMULATION_NAME}_emulation): Likewise.
	* emultempl/m68kcoff.em (ld_${EMULATION_NAME}_emulation): Likewise.
	* emultempl/msp430.em (ld_${EMULATION_NAME}_emulation): Likewise.
	* emultempl/pe.em (ld_${EMULATION_NAME}_emulation): Likewise.
	* emultempl/pep.em (ld_${EMULATION_NAME}_emulation): Likewise.
	* emultempl/sunos.em (ld_${EMULATION_NAME}_emulation): Likewise.
	* emultempl/ticoff.em (ld_${EMULATION_NAME}_emulation): Likewise.
	* emultempl/vanilla.em (ld_${EMULATION_NAME}_emulation): Likewise.
	* emultempl/elf32.em (gld${EMULATION_NAME}_before_parse): Always
	set link_info.check_relocs_after_open_input to TRUE.
	(ld_${EMULATION_NAME}_emulation): Add $LDEMUL_AFTER_CHECK_RELOCS.
	* emultempl/linux.em (gld${EMULATION_NAME}_before_parse):
	Set link_info.check_relocs_after_open_input to TRUE.
	(ld_${EMULATION_NAME}_emulation): Add after_check_relocs_default.
	* emultempl/mmix-elfnmmo.em (mmix_before_parse): New function.
	(LDEMUL_BEFORE_PARSE): New.
	* emultempl/mmixelf.em (elfmmix_before_parse): Replace
	gld${EMULATION_NAME}_before_parse with mmix_before_parse.
	* emultempl/ppc32elf.em (ppc_after_open): Renamed to ...
	(ppc_after_check_relocs): This.  Call after_check_relocs_default
	instead of gld${EMULATION_NAME}_after_open.
	(LDEMUL_AFTER_OPEN): Removed.
	(LDEMUL_AFTER_CHECK_RELOCS): New.
	* ldemul.c (ldemul_after_check_relocs): New.
	(after_check_relocs_default): Likewise.
	* ldemul.h (ldemul_after_check_relocs): Likewise.
	(after_check_relocs_default): Likewise.
	(ld_emulation_xfer_struct): Add after_check_relocs.
	* ldlang.c (lang_process): Call ldemul_after_check_relocs after
	lang_check_relocs.
	* testsuite/ld-aarch64/gc-got-relocs.d: Don't expect GOT section.
	* testsuite/ld-aarch64/gc-tls-relocs.d: Likewise.
	* testsuite/ld-cris/tls-gc-68.d: Likewise.
	* testsuite/ld-cris/tls-gc-69.d: Likewise.
	* testsuite/ld-cris/tls-gc-70.d: Likewise.
	* testsuite/ld-cris/tls-gc-75.d: Likewise.
	* testsuite/ld-cris/tls-gc-79.d: Likewise.
	* testsuite/ld-mmix/bpo-10.d: Don't expect .MMIX.reg_contents
	section.

1 files changed, 1 insertions, 195 deletions

diff --git a/bfd/elf32-m68k.c b/bfd/elf32-m68k.c
index 501190d..d9a2cb8 100644
--- a/bfd/elf32-m68k.c
+++ b/bfd/elf32-m68k.c
@@ -695,8 +695,7 @@ struct elf_m68k_got_entry
   {
     struct
     {
-      /* Number of times this entry is referenced.  It is used to
-	 filter out unnecessary GOT slots in elf_m68k_gc_sweep_hook.  */
+      /* Number of times this entry is referenced.  */
       bfd_vma refcount;
     } s1;
 
@@ -1606,27 +1605,6 @@ elf_m68k_update_got_entry_type (struct elf_m68k_got *got,
   return was;
 }
 
-/* Update GOT counters when removing an entry of type TYPE.  */
-
-static void
-elf_m68k_remove_got_entry_type (struct elf_m68k_got *got,
-				enum elf_m68k_reloc_type type)
-{
-  enum elf_m68k_got_offset_size os;
-  bfd_vma n_slots;
-
-  n_slots = elf_m68k_reloc_got_n_slots (type);
-
-  /* Decrese counter of slots with offset size corresponding to TYPE
-     and all greater offset sizes.  */
-  for (os = elf_m68k_reloc_got_offset_size (type); os <= R_32; ++os)
-    {
-      BFD_ASSERT (got->n_slots[os] >= n_slots);
-
-      got->n_slots[os] -= n_slots;
-    }
-}
-
 /* Add new or update existing entry to GOT.
    H, ABFD, TYPE and SYMNDX is data for the entry.
    INFO is a context where memory should be allocated.  */
@@ -2455,52 +2433,6 @@ elf_m68k_partition_multi_got (struct bfd_link_info *info)
   return TRUE;
 }
 
-/* Specialized version of elf_m68k_get_got_entry that returns pointer
-   to hashtable slot, thus allowing removal of entry via
-   elf_m68k_remove_got_entry.  */
-
-static struct elf_m68k_got_entry **
-elf_m68k_find_got_entry_ptr (struct elf_m68k_got *got,
-			     struct elf_m68k_got_entry_key *key)
-{
-  void **ptr;
-  struct elf_m68k_got_entry entry_;
-  struct elf_m68k_got_entry **entry_ptr;
-
-  entry_.key_ = *key;
-  ptr = htab_find_slot (got->entries, &entry_, NO_INSERT);
-  BFD_ASSERT (ptr != NULL);
-
-  entry_ptr = (struct elf_m68k_got_entry **) ptr;
-
-  return entry_ptr;
-}
-
-/* Remove entry pointed to by ENTRY_PTR from GOT.  */
-
-static void
-elf_m68k_remove_got_entry (struct elf_m68k_got *got,
-			   struct elf_m68k_got_entry **entry_ptr)
-{
-  struct elf_m68k_got_entry *entry;
-
-  entry = *entry_ptr;
-
-  /* Check that offsets have not been finalized yet.  */
-  BFD_ASSERT (got->offset == (bfd_vma) -1);
-  /* Check that this entry is indeed unused.  */
-  BFD_ASSERT (entry->u.s1.refcount == 0);
-
-  elf_m68k_remove_got_entry_type (got, entry->key_.type);
-
-  if (entry->key_.bfd != NULL)
-    got->local_n_slots -= elf_m68k_reloc_got_n_slots (entry->key_.type);
-
-  BFD_ASSERT (got->n_slots[R_32] >= got->local_n_slots);
-
-  htab_clear_slot (got->entries, (void **) entry_ptr);
-}
-
 /* Copy any information related to dynamic linking from a pre-existing
    symbol to a newly created symbol.  Also called to copy flags and
    other back-end info to a weakdef, in which case the symbol is not
@@ -2905,131 +2837,6 @@ elf_m68k_gc_mark_hook (asection *sec,
 
   return _bfd_elf_gc_mark_hook (sec, info, rel, h, sym);
 }
-
-/* Update the got entry reference counts for the section being removed.  */
-
-static bfd_boolean
-elf_m68k_gc_sweep_hook (bfd *abfd,
-			struct bfd_link_info *info,
-			asection *sec,
-			const Elf_Internal_Rela *relocs)
-{
-  Elf_Internal_Shdr *symtab_hdr;
-  struct elf_link_hash_entry **sym_hashes;
-  const Elf_Internal_Rela *rel, *relend;
-  bfd *dynobj;
-  struct elf_m68k_got *got;
-
-  if (bfd_link_relocatable (info))
-    return TRUE;
-
-  dynobj = elf_hash_table (info)->dynobj;
-  if (dynobj == NULL)
-    return TRUE;
-
-  symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
-  sym_hashes = elf_sym_hashes (abfd);
-  got = NULL;
-
-  relend = relocs + sec->reloc_count;
-  for (rel = relocs; rel < relend; rel++)
-    {
-      unsigned long r_symndx;
-      struct elf_link_hash_entry *h = NULL;
-
-      r_symndx = ELF32_R_SYM (rel->r_info);
-      if (r_symndx >= symtab_hdr->sh_info)
-	{
-	  h = sym_hashes[r_symndx - symtab_hdr->sh_info];
-	  while (h->root.type == bfd_link_hash_indirect
-		 || h->root.type == bfd_link_hash_warning)
-	    h = (struct elf_link_hash_entry *) h->root.u.i.link;
-	}
-
-      switch (ELF32_R_TYPE (rel->r_info))
-	{
-	case R_68K_GOT8:
-	case R_68K_GOT16:
-	case R_68K_GOT32:
-	  if (h != NULL
-	      && strcmp (h->root.root.string, "_GLOBAL_OFFSET_TABLE_") == 0)
-	    break;
-
-	  /* FALLTHRU */
-	case R_68K_GOT8O:
-	case R_68K_GOT16O:
-	case R_68K_GOT32O:
-	  /* Fall through.  */
-
-	  /* TLS relocations.  */
-	case R_68K_TLS_GD8:
-	case R_68K_TLS_GD16:
-	case R_68K_TLS_GD32:
-	case R_68K_TLS_LDM8:
-	case R_68K_TLS_LDM16:
-	case R_68K_TLS_LDM32:
-	case R_68K_TLS_IE8:
-	case R_68K_TLS_IE16:
-	case R_68K_TLS_IE32:
-
-	case R_68K_TLS_TPREL32:
-	case R_68K_TLS_DTPREL32:
-
-	  if (got == NULL)
-	    {
-	      got = elf_m68k_get_bfd2got_entry (elf_m68k_multi_got (info),
-						abfd, MUST_FIND, NULL)->got;
-	      BFD_ASSERT (got != NULL);
-	    }
-
-	  {
-	    struct elf_m68k_got_entry_key key_;
-	    struct elf_m68k_got_entry **got_entry_ptr;
-	    struct elf_m68k_got_entry *got_entry;
-
-	    elf_m68k_init_got_entry_key (&key_, h, abfd, r_symndx,
-					 ELF32_R_TYPE (rel->r_info));
-	    got_entry_ptr = elf_m68k_find_got_entry_ptr (got, &key_);
-
-	    got_entry = *got_entry_ptr;
-
-	    if (got_entry->u.s1.refcount > 0)
-	      {
-		--got_entry->u.s1.refcount;
-
-		if (got_entry->u.s1.refcount == 0)
-		  /* We don't need the .got entry any more.  */
-		  elf_m68k_remove_got_entry (got, got_entry_ptr);
-	      }
-	  }
-	  break;
-
-	case R_68K_PLT8:
-	case R_68K_PLT16:
-	case R_68K_PLT32:
-	case R_68K_PLT8O:
-	case R_68K_PLT16O:
-	case R_68K_PLT32O:
-	case R_68K_PC8:
-	case R_68K_PC16:
-	case R_68K_PC32:
-	case R_68K_8:
-	case R_68K_16:
-	case R_68K_32:
-	  if (h != NULL)
-	    {
-	      if (h->plt.refcount > 0)
-		--h->plt.refcount;
-	    }
-	  break;
-
-	default:
-	  break;
-	}
-    }
-
-  return TRUE;
-}
 
 /* Return the type of PLT associated with OUTPUT_BFD.  */
 
@@ -4826,7 +4633,6 @@ elf_m68k_add_symbol_hook (bfd *abfd,
 #define elf_backend_finish_dynamic_sections \
 					elf_m68k_finish_dynamic_sections
 #define elf_backend_gc_mark_hook	elf_m68k_gc_mark_hook
-#define elf_backend_gc_sweep_hook	elf_m68k_gc_sweep_hook
 #define elf_backend_copy_indirect_symbol elf_m68k_copy_indirect_symbol
 #define bfd_elf32_bfd_merge_private_bfd_data \
                                         elf32_m68k_merge_private_bfd_data