[binutils-gdb] non_ir_ref_dynamic

[Alan Modra <amodra at sourceware dot org>]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=4070765b1a1640ff8f43483cd9ee06727f658dfe

commit 4070765b1a1640ff8f43483cd9ee06727f658dfe
Author: Alan Modra <amodra@gmail.com>
Date:   Tue May 16 07:56:41 2017 +0930

    non_ir_ref_dynamic
    
    dynamic_ref_after_ir_def is a little odd compared to other symbol
    flags in that as the name suggests, it is set only for certain
    references after a definition.  It turns out that setting a flag for
    any non-ir reference from a dynamic object can be used to solve the
    problem for which this flag was invented, which I think is a cleaner.
    This patch does that, and sets non_ir_ref only for regular object
    references.
    
    include/
    	* bfdlink.h (struct bfd_link_hash_entry): Update non_ir_ref
    	comment.  Rename dynamic_ref_after_ir_def to non_ir_ref_dynamic.
    ld/
    	* plugin.c (is_visible_from_outside): Use non_ir_ref_dynamic.
    	(plugin_notice): Set non_ir_ref for references from regular
    	objects, non_ir_ref_dynamic for references from dynamic objects.
    bfd/
    	* elf64-ppc.c (add_symbol_adjust): Transfer non_ir_ref_dynamic.
    	* elflink.c (elf_link_add_object_symbols): Update to use
    	non_ir_ref_dynamic.
    	(elf_link_input_bfd): Test non_ir_ref_dynamic in addition to
    	non_ir_ref.
    	* linker.c (_bfd_generic_link_add_one_symbol): Likewise.

Diff:
---
 bfd/ChangeLog     |  9 ++++++++
 bfd/elf64-ppc.c   |  1 +
 bfd/elflink.c     | 11 +++++-----
 bfd/linker.c      |  3 ++-
 include/ChangeLog |  5 +++++
 include/bfdlink.h | 10 ++++-----
 ld/ChangeLog      |  6 +++++
 ld/plugin.c       | 65 ++++++++++++++++++++++++++++++-------------------------
 8 files changed, 69 insertions(+), 41 deletions(-)

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index 52c192d..8b3f1a5 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,12 @@
+2017-05-16  Alan Modra  <amodra@gmail.com>
+
+	* elf64-ppc.c (add_symbol_adjust): Transfer non_ir_ref_dynamic.
+	* elflink.c (elf_link_add_object_symbols): Update to use
+	non_ir_ref_dynamic.
+	(elf_link_input_bfd): Test non_ir_ref_dynamic in addition to
+	non_ir_ref.
+	* linker.c (_bfd_generic_link_add_one_symbol): Likewise.
+
 2017-05-15  Maciej W. Rozycki  <macro@imgtec.com>
 
 	* elfxx-mips.c (print_mips_ases): Handle MIPS16e2 ASE.
diff --git a/bfd/elf64-ppc.c b/bfd/elf64-ppc.c
index a20d9b3..a2cc373 100644
--- a/bfd/elf64-ppc.c
+++ b/bfd/elf64-ppc.c
@@ -5119,6 +5119,7 @@ add_symbol_adjust (struct ppc_link_hash_entry *eh, struct bfd_link_info *info)
       /* Propagate reference flags from entry symbol to function
 	 descriptor symbol.  */
       fdh->elf.root.non_ir_ref |= eh->elf.root.non_ir_ref;
+      fdh->elf.root.non_ir_ref_dynamic |= eh->elf.root.non_ir_ref_dynamic;
       fdh->elf.ref_regular |= eh->elf.ref_regular;
       fdh->elf.ref_regular_nonweak |= eh->elf.ref_regular_nonweak;
 
diff --git a/bfd/elflink.c b/bfd/elflink.c
index ba50b68..8eaf533 100644
--- a/bfd/elflink.c
+++ b/bfd/elflink.c
@@ -4939,7 +4939,7 @@ error_free_dyn:
 	  struct elf_link_hash_entry *h;
 	  bfd_size_type size;
 	  unsigned int alignment_power;
-	  unsigned int dynamic_ref_after_ir_def;
+	  unsigned int non_ir_ref_dynamic;
 
 	  for (p = htab->root.table.table[i]; p != NULL; p = p->next)
 	    {
@@ -4961,10 +4961,10 @@ error_free_dyn:
 		  size = 0;
 		  alignment_power = 0;
 		}
-	      /* Preserve dynamic_ref_after_ir_def so that this symbol
+	      /* Preserve non_ir_ref_dynamic so that this symbol
 		 will be exported when the dynamic lib becomes needed
 		 in the second pass.  */
-	      dynamic_ref_after_ir_def = h->root.dynamic_ref_after_ir_def;
+	      non_ir_ref_dynamic = h->root.non_ir_ref_dynamic;
 	      memcpy (p, old_ent, htab->root.table.entsize);
 	      old_ent = (char *) old_ent + htab->root.table.entsize;
 	      h = (struct elf_link_hash_entry *) p;
@@ -4981,7 +4981,7 @@ error_free_dyn:
 		  if (alignment_power > h->root.u.c.p->alignment_power)
 		    h->root.u.c.p->alignment_power = alignment_power;
 		}
-	      h->root.dynamic_ref_after_ir_def = dynamic_ref_after_ir_def;
+	      h->root.non_ir_ref_dynamic = non_ir_ref_dynamic;
 	    }
 	}
 
@@ -10472,7 +10472,8 @@ elf_link_input_bfd (struct elf_final_link_info *flinfo, bfd *input_bfd)
 		     linker may attach linker created dynamic sections
 		     to the plugin bfd.  Symbols defined in linker
 		     created sections are not plugin symbols.  */
-		  if (h->root.non_ir_ref
+		  if ((h->root.non_ir_ref
+		       || h->root.non_ir_ref_dynamic)
 		      && (h->root.type == bfd_link_hash_defined
 			  || h->root.type == bfd_link_hash_defweak)
 		      && (h->root.u.def.section->flags
diff --git a/bfd/linker.c b/bfd/linker.c
index 2f56b46..1f493a3 100644
--- a/bfd/linker.c
+++ b/bfd/linker.c
@@ -1735,7 +1735,8 @@ _bfd_generic_link_add_one_symbol (struct bfd_link_info *info,
 	     otherwise add a warning.  */
 	  if ((!info->lto_plugin_active
 	       && (h->u.undef.next != NULL || info->hash->undefs_tail == h))
-	      || h->non_ir_ref)
+	      || h->non_ir_ref
+	      || h->non_ir_ref_dynamic)
 	    {
 	      (*info->callbacks->warning) (info, string, h->root.string,
 					   hash_entry_bfd (h), NULL, 0);
diff --git a/include/ChangeLog b/include/ChangeLog
index 67bf02f..8425760 100644
--- a/include/ChangeLog
+++ b/include/ChangeLog
@@ -1,3 +1,8 @@
+2017-05-16  Alan Modra  <amodra@gmail.com>
+
+	* bfdlink.h (struct bfd_link_hash_entry): Update non_ir_ref
+	comment.  Rename dynamic_ref_after_ir_def to non_ir_ref_dynamic.
+
 2017-05-15  Maciej W. Rozycki  <macro@imgtec.com>
 	    Matthew Fortune  <matthew.fortune@imgtec.com>
 
diff --git a/include/bfdlink.h b/include/bfdlink.h
index cb4bad9..41f5338 100644
--- a/include/bfdlink.h
+++ b/include/bfdlink.h
@@ -100,13 +100,13 @@ struct bfd_link_hash_entry
   /* Type of this entry.  */
   ENUM_BITFIELD (bfd_link_hash_type) type : 8;
 
-  /* Symbol is referenced in a normal object file, as distict from a LTO
-     IR object file.  */
+  /* Symbol is referenced in a normal regular object file,
+     as distinct from a LTO IR object file.  */
   unsigned int non_ir_ref : 1;
 
-  /* Symbol is referenced in a dynamic object after it has been defined
-     in an IR object.  */
-  unsigned int dynamic_ref_after_ir_def : 1;
+  /* Symbol is referenced in a normal dynamic object file,
+     as distinct from a LTO IR object file.  */
+  unsigned int non_ir_ref_dynamic : 1;
 
   /* Symbol is a built-in define.  These will be overridden by PROVIDE
      in a linker script.  */
diff --git a/ld/ChangeLog b/ld/ChangeLog
index a8dad5c..9fdd758 100644
--- a/ld/ChangeLog
+++ b/ld/ChangeLog
@@ -1,3 +1,9 @@
+2017-05-16  Alan Modra  <amodra@gmail.com>
+
+	* plugin.c (is_visible_from_outside): Use non_ir_ref_dynamic.
+	(plugin_notice): Set non_ir_ref for references from regular
+	objects, non_ir_ref_dynamic for references from dynamic objects.
+
 2017-05-15  Maciej W. Rozycki  <macro@imgtec.com>
 
 	* testsuite/ld-mips-elf/mips16e2-pcrel-0.d: New test.
diff --git a/ld/plugin.c b/ld/plugin.c
index 164b5db..087cedc 100644
--- a/ld/plugin.c
+++ b/ld/plugin.c
@@ -629,7 +629,7 @@ is_visible_from_outside (struct ld_plugin_symbol *lsym,
 
   if (bfd_link_relocatable (&link_info))
     return TRUE;
-  if (blhe->dynamic_ref_after_ir_def
+  if (blhe->non_ir_ref_dynamic
       || link_info.export_dynamic
       || bfd_link_dll (&link_info))
     {
@@ -1266,9 +1266,10 @@ plugin_call_cleanup (void)
 /* To determine which symbols should be resolved LDPR_PREVAILING_DEF
    and which LDPR_PREVAILING_DEF_IRONLY, we notice all the symbols as
    the linker adds them to the linker hash table.  Mark those
-   referenced from a non-IR file with non_ir_ref.  We have to
-   notice_all symbols, because we won't necessarily know until later
-   which ones will be contributed by IR files.  */
+   referenced from a non-IR file with non_ir_ref or
+   non_ir_ref_dynamic as appropriate.  We have to notice_all symbols,
+   because we won't necessarily know until later which ones will be
+   contributed by IR files.  */
 static bfd_boolean
 plugin_notice (struct bfd_link_info *info,
 	       struct bfd_link_hash_entry *h,
@@ -1283,6 +1284,7 @@ plugin_notice (struct bfd_link_info *info,
   if (h != NULL)
     {
       bfd *sym_bfd;
+      bfd_boolean ref = FALSE;
 
       if (h->type == bfd_link_hash_warning)
 	h = h->u.i.link;
@@ -1298,13 +1300,17 @@ plugin_notice (struct bfd_link_info *info,
 	{
 	  /* ??? Some of this is questionable.  See comments in
 	     _bfd_generic_link_add_one_symbol for case IND.  */
-	  if (h->type != bfd_link_hash_new)
+	  if (h->type != bfd_link_hash_new
+	      || inh->type == bfd_link_hash_new)
 	    {
-	      h->non_ir_ref = TRUE;
-	      inh->non_ir_ref = TRUE;
+	      if ((abfd->flags & DYNAMIC) == 0)
+		inh->non_ir_ref = TRUE;
+	      else
+		inh->non_ir_ref_dynamic = TRUE;
 	    }
-	  else if (inh->type == bfd_link_hash_new)
-	    inh->non_ir_ref = TRUE;
+
+	  if (h->type != bfd_link_hash_new)
+	    ref = TRUE;
 	}
 
       /* Nothing to do here for warning symbols.  */
@@ -1318,34 +1324,18 @@ plugin_notice (struct bfd_link_info *info,
       /* If this is a ref, set non_ir_ref.  */
       else if (bfd_is_und_section (section))
 	{
-	   if (h->type == bfd_link_hash_defweak
-	       || h->type == bfd_link_hash_defined)
-	     {
-	       /* Check if the symbol is referenced in a dynamic object
-		  after it has been defined in an IR object.  */
-	       if ((abfd->flags & DYNAMIC) != 0
-		   && is_ir_dummy_bfd (h->u.def.section->owner))
-		 h->dynamic_ref_after_ir_def = TRUE;
-	     }
 	  /* Replace the undefined dummy bfd with the real one.  */
-	   else if ((h->type == bfd_link_hash_undefined
-		     || h->type == bfd_link_hash_undefweak)
-		    && (h->u.undef.abfd == NULL
-			|| (h->u.undef.abfd->flags & BFD_PLUGIN) != 0))
+	   if ((h->type == bfd_link_hash_undefined
+		|| h->type == bfd_link_hash_undefweak)
+	       && (h->u.undef.abfd == NULL
+		   || (h->u.undef.abfd->flags & BFD_PLUGIN) != 0))
 	     h->u.undef.abfd = abfd;
-	  h->non_ir_ref = TRUE;
+	  ref = TRUE;
 	}
 
       /* Otherwise, it must be a new def.  */
       else
 	{
-	  /* A common symbol should be merged with other commons or
-	     defs with the same name.  In particular, a common ought
-	     to be overridden by a def in a -flto object.  In that
-	     sense a common is also a ref.  */
-	  if (bfd_is_com_section (section))
-	    h->non_ir_ref = TRUE;
-
 	  /* Ensure any symbol defined in an IR dummy BFD takes on a
 	     new value from a real BFD.  Weak symbols are not normally
 	     overridden by a new weak definition, and strong symbols
@@ -1360,6 +1350,21 @@ plugin_notice (struct bfd_link_info *info,
 	      h->type = bfd_link_hash_undefweak;
 	      h->u.undef.abfd = sym_bfd;
 	    }
+
+	  /* A common symbol should be merged with other commons or
+	     defs with the same name.  In particular, a common ought
+	     to be overridden by a def in a -flto object.  In that
+	     sense a common is also a ref.  */
+	  if (bfd_is_com_section (section))
+	    ref = TRUE;
+	}
+
+      if (ref)
+	{
+	  if ((abfd->flags & DYNAMIC) == 0)
+	    h->non_ir_ref = TRUE;
+	  else
+	    h->non_ir_ref_dynamic = TRUE;
 	}
     }