This is the mail archive of the binutils@sources.redhat.com mailing list for the binutils project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: PATCH: IA64 unwind section references discarded section


On Fri, Apr 01, 2005 at 03:37:47PM -0800, H. J. Lu wrote:
> On Thu, Mar 31, 2005 at 10:20:27PM -0800, H. J. Lu wrote:
> > This is the same problem as
> > 
> > http://sourceware.org/ml/binutils/2004-08/msg00187.html
> > http://sourceware.org/ml/binutils/2004-08/msg00190.html
> > 
> > But this time it is icc, which doesn't use gas. I would like to see a
> > linker solution.
> > 
> > 
> 
> This is a linker patch. It creates a fake group section for a
> linkonce text sections and its unwind sections. The fake group
> section is removed before the output file is written.
> 

This updated patch works for me.


H.J.
----
bfd/

2005-04-02  H.J. Lu  <hongjiu.lu@intel.com>

	* elf.c (bfd_elf_set_group_contents): Ignore linker created
	group section. 
	(assign_section_numbers): Remove the linker created group
	sections.

	* elfxx-ia64.c (elfNN_ia64_object_p): New.
	(elf_backend_object_p): Defined.

gas/

2005-04-02  H.J. Lu  <hongjiu.lu@intel.com>

	* config/tc-ia64.c (start_unwind_section): Undo the change
	of 2004-08-18.
	(generate_unwind_image, dot_endp): Likewise.

--- binutils/bfd/elf.c.unwind	2005-04-01 17:45:16.000000000 -0800
+++ binutils/bfd/elf.c	2005-04-02 07:55:42.154467729 -0800
@@ -2635,7 +2635,9 @@ bfd_elf_set_group_contents (bfd *abfd, a
   struct bfd_link_order *l;
   bfd_boolean gas;
 
-  if (elf_section_data (sec)->this_hdr.sh_type != SHT_GROUP
+  /* Ignore linker created group section.  See elfNN_ia64_object_p in
+     elfxx-ia64.c.  */
+  if (((sec->flags & (SEC_GROUP | SEC_LINKER_CREATED)) != SEC_GROUP)
       || *failedptr)
     return;
 
@@ -2729,29 +2731,55 @@ static bfd_boolean
 assign_section_numbers (bfd *abfd)
 {
   struct elf_obj_tdata *t = elf_tdata (abfd);
-  asection *sec;
+  asection *sec, **group_secp;
   unsigned int section_number, secn;
   Elf_Internal_Shdr **i_shdrp;
   bfd_size_type amt;
   struct bfd_elf_section_data *d;
+  bfd_boolean found;
 
   section_number = 1;
 
   _bfd_elf_strtab_clear_all_refs (elf_shstrtab (abfd));
 
   /* Put SHT_GROUP sections first.  */
+  group_secp = &abfd->sections;
+  found = FALSE;
   for (sec = abfd->sections; sec; sec = sec->next)
     {
       d = elf_section_data (sec);
 
       if (d->this_hdr.sh_type == SHT_GROUP)
 	{
+	  if (sec->flags & SEC_LINKER_CREATED)
+	    {
+	      /* Find the first linker screated SHT_GROUP section.  */
+	      found = TRUE;
+	    }
 	  if (section_number == SHN_LORESERVE)
 	    section_number += SHN_HIRESERVE + 1 - SHN_LORESERVE;
 	  d->this_idx = section_number++;
 	}
+
+      if (!found)
+	group_secp = &(*group_secp)->next;
     }
 
+  /* Remove the linker created SHT_GROUP sections.  */
+  if (found)
+    do
+      {
+	if (((*group_secp)->flags & (SEC_GROUP | SEC_LINKER_CREATED))
+	    == (SEC_GROUP | SEC_LINKER_CREATED))
+	  {
+	    bfd_section_list_remove (abfd, group_secp);
+	    abfd->section_count--;
+	  }
+	else
+	  group_secp = &(*group_secp)->next;
+      }
+    while (*group_secp);
+
   for (sec = abfd->sections; sec; sec = sec->next)
     {
       d = elf_section_data (sec);
--- binutils/bfd/elfxx-ia64.c.unwind	2005-03-21 13:13:37.000000000 -0800
+++ binutils/bfd/elfxx-ia64.c	2005-04-02 07:51:04.764390400 -0800
@@ -4886,6 +4886,118 @@ static struct bfd_elf_special_section co
 };
 
 static bfd_boolean
+elfNN_ia64_object_p (bfd *abfd)
+{
+  asection *sec;
+  unsigned int num_group = 0;
+
+  if (abfd->flags & DYNAMIC)
+    return TRUE;
+
+  /* Count number of .gnu.linkonce.t.* sections which aren't in a
+     section group.  */
+  for (sec = abfd->sections; sec != NULL; sec = sec->next)
+    {
+      if (elf_sec_group (sec) == NULL
+	  && ((sec->flags & (SEC_LINK_ONCE | SEC_CODE | SEC_GROUP))
+	      == (SEC_LINK_ONCE | SEC_CODE))
+	  && strncmp (sec->name, ".gnu.linkonce.t.", 16) == 0)
+	num_group++;
+    }
+
+  if (num_group)
+    {
+      asection *group, *unwi, *unw;
+      flagword flags;
+      const char *name;
+      char *unwi_name, *unw_name;
+      bfd_size_type amt;
+      Elf_Internal_Shdr shdr;
+
+      /* Fake SHT_GROUP section header.  */
+      memset (&shdr, 0, sizeof (shdr));
+      shdr.sh_type = SHT_GROUP;
+
+      /* Flags for fake group section.  */
+      flags = (SEC_LINKER_CREATED | SEC_GROUP | SEC_LINK_ONCE
+	       | SEC_EXCLUDE);
+
+      /* We add a fake section group for each linkonce text section and
+	 its unwind sections.  */
+      for (sec = abfd->sections; sec != NULL; sec = sec->next)
+	{
+	  if (elf_sec_group (sec) == NULL
+	      && ((sec->flags & (SEC_LINK_ONCE | SEC_CODE | SEC_GROUP))
+		  == (SEC_LINK_ONCE | SEC_CODE))
+	      && strncmp (sec->name, ".gnu.linkonce.t.", 16) == 0)
+	    {
+	      name = sec->name + 16;
+
+	      amt = strlen (name) + sizeof (".gnu.linkonce.ia64unwi.");
+	      unwi_name = bfd_alloc (abfd, amt);
+	      if (!unwi_name)
+		return FALSE;
+
+	      strcpy (stpcpy (unwi_name, ".gnu.linkonce.ia64unwi."),
+		      name);
+	      unwi = bfd_get_section_by_name (abfd, unwi_name);
+
+	      amt = strlen (name) + sizeof (".gnu.linkonce.ia64unw.");
+	      unw_name = bfd_alloc (abfd, amt);
+	      if (!unw_name)
+		return FALSE;
+
+	      strcpy (stpcpy (unw_name, ".gnu.linkonce.ia64unw."),
+		      name);
+	      unw = bfd_get_section_by_name (abfd, unw_name);
+
+	      /* We need to create a fake group section for it and its
+		 unwind sections.  */
+	      group = bfd_make_section_anyway (abfd, name);
+	      if (group == NULL
+		  || ! bfd_set_section_flags (abfd, group, flags))
+		return FALSE;
+
+	      elf_next_in_group (group) = sec;
+
+	      elf_group_name (sec) = name;
+	      elf_next_in_group (sec) = sec;
+	      elf_sec_group (sec) = group;
+
+	      if (unwi)
+		{
+		  elf_group_name (unwi) = name;
+		  elf_next_in_group (unwi) = sec;
+		  elf_next_in_group (sec) = unwi;
+		  elf_sec_group (unwi) = group;
+		}
+
+	      if (unw)
+		{
+		  elf_group_name (unw) = name;
+		  if (unwi)
+		    {
+		      elf_next_in_group (unw)
+			= elf_next_in_group (unwi);
+		      elf_next_in_group (unwi) = unw;
+		    }
+		  else
+		    {
+		      elf_next_in_group (unw) = sec;
+		      elf_next_in_group (sec) = unw;
+		    }
+		  elf_sec_group (unw) = group;
+		}
+
+	      shdr.bfd_section = group;
+	      elf_section_data (group)->this_hdr = shdr;
+	    }
+	}
+    }
+  return TRUE;
+}
+
+static bfd_boolean
 elfNN_ia64_hpux_vec (const bfd_target *vec)
 {
   extern const bfd_target bfd_elfNN_ia64_hpux_big_vec;
@@ -4968,6 +5080,9 @@ elfNN_hpux_backend_symbol_processing (bf
 #define bfd_elfNN_bfd_relax_section \
 	elfNN_ia64_relax_section
 
+#define elf_backend_object_p \
+	elfNN_ia64_object_p
+
 /* Stuff for the BFD linker: */
 #define bfd_elfNN_bfd_link_hash_table_create \
 	elfNN_ia64_hash_table_create
--- binutils/gas/config/tc-ia64.c.unwind	2005-04-01 17:45:20.000000000 -0800
+++ binutils/gas/config/tc-ia64.c	2005-04-01 17:53:16.000000000 -0800
@@ -3460,7 +3460,7 @@ static char *special_linkonce_name[] =
   };
 
 static void
-start_unwind_section (const segT text_seg, int sec_index, int linkonce_empty)
+start_unwind_section (const segT text_seg, int sec_index)
 {
   /*
     Use a slightly ugly scheme to derive the unwind section names from
@@ -3522,8 +3522,6 @@ start_unwind_section (const segT text_se
       prefix = special_linkonce_name [sec_index - SPECIAL_SECTION_UNWIND];
       suffix += sizeof (".gnu.linkonce.t.") - 1;
     }
-  else if (linkonce_empty)
-    return;
 
   prefix_len = strlen (prefix);
   suffix_len = strlen (suffix);
@@ -3611,7 +3609,7 @@ generate_unwind_image (const segT text_s
       expressionS exp;
       bfd_reloc_code_real_type reloc;
 
-      start_unwind_section (text_seg, SPECIAL_SECTION_UNWIND_INFO, 0);
+      start_unwind_section (text_seg, SPECIAL_SECTION_UNWIND_INFO);
 
       /* Make sure the section has 4 byte alignment for ILP32 and
 	 8 byte alignment for LP64.  */
@@ -3652,8 +3650,6 @@ generate_unwind_image (const segT text_s
 	  unwind.personality_routine = 0;
 	}
     }
-  else
-    start_unwind_section (text_seg, SPECIAL_SECTION_UNWIND_INFO, 1);
 
   free_saved_prologue_counts ();
   unwind.list = unwind.tail = unwind.current_entry = NULL;
@@ -4426,7 +4422,7 @@ dot_endp (dummy)
       subseg_set (md.last_text_seg, 0);
       proc_end = expr_build_dot ();
 
-      start_unwind_section (saved_seg, SPECIAL_SECTION_UNWIND, 0);
+      start_unwind_section (saved_seg, SPECIAL_SECTION_UNWIND);
 
       /* Make sure that section has 4 byte alignment for ILP32 and
          8 byte alignment for LP64.  */
@@ -4466,9 +4462,6 @@ dot_endp (dummy)
 			    bytes_per_address);
 
     }
-  else
-    start_unwind_section (saved_seg, SPECIAL_SECTION_UNWIND, 1);
-
   subseg_set (saved_seg, saved_subseg);
 
   if (unwind.proc_start)


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]