x86: Add _bfd_x86_elf_get_synthetic_symtab

Move the common codes in elf_i386_get_synthetic_symtab and
elf_x86_64_get_synthetic_symtab to _bfd_x86_elf_get_synthetic_symtab.

	* elf32-i386.c (elf_i386_plt_type): Removed.
	(elf_i386_plt): Likewise.
	(elf_i386_get_synthetic_symtab): Updated.   Call
	_bfd_x86_elf_get_synthetic_symtab.
	* elf64-x86-64.c (elf_x86_64_plt_type): Removed.
	(elf_x86_64_plt): Likewise.
	(elf_x86_64_get_synthetic_symtab): Updated.  Call
	_bfd_x86_elf_get_synthetic_symtab.
	* elfxx-x86.c (elf_i386_get_plt_got_vma): New function.
	(elf_x86_64_get_plt_got_vma): Likewise.
	(elf_i386_valid_plt_reloc_p): Likewise.
	(elf_x86_64_valid_plt_reloc_p): Likewise.
	(_bfd_x86_elf_get_synthetic_symtab): Likewise.
	* elfxx-x86.h (elf_x86_plt_type): New.
	(elf_x86_plt): Likewise.
	(_bfd_x86_elf_get_synthetic_symtab): Likewise.

1 files changed, 241 insertions, 0 deletions

diff --git a/bfd/elfxx-x86.c b/bfd/elfxx-x86.c
index d040ee3..eb02ed2 100644
--- a/bfd/elfxx-x86.c
+++ b/bfd/elfxx-x86.c
@@ -530,6 +530,247 @@ _bfd_x86_elf_hash_symbol (struct elf_link_hash_entry *h)
   return _bfd_elf_hash_symbol (h);
 }
 
+static bfd_vma
+elf_i386_get_plt_got_vma (struct elf_x86_plt *plt_p ATTRIBUTE_UNUSED,
+			  bfd_vma off,
+			  bfd_vma offset ATTRIBUTE_UNUSED,
+			  bfd_vma got_addr)
+{
+  return got_addr + off;
+}
+
+static bfd_vma
+elf_x86_64_get_plt_got_vma (struct elf_x86_plt *plt_p,
+			    bfd_vma off,
+			    bfd_vma offset,
+			    bfd_vma got_addr ATTRIBUTE_UNUSED)
+{
+  return plt_p->sec->vma + offset + off + plt_p->plt_got_insn_size;
+}
+
+static bfd_boolean
+elf_i386_valid_plt_reloc_p (unsigned int type)
+{
+  return (type == R_386_JUMP_SLOT
+	  || type == R_386_GLOB_DAT
+	  || type == R_386_IRELATIVE);
+}
+
+static bfd_boolean
+elf_x86_64_valid_plt_reloc_p (unsigned int type)
+{
+  return (type == R_X86_64_JUMP_SLOT
+	  || type == R_X86_64_GLOB_DAT
+	  || type == R_X86_64_IRELATIVE);
+}
+
+long
+_bfd_x86_elf_get_synthetic_symtab (bfd *abfd,
+				   long count,
+				   long relsize,
+				   bfd_vma got_addr,
+				   struct elf_x86_plt plts[],
+				   asymbol **dynsyms,
+				   asymbol **ret)
+{
+  long size, i, n, len;
+  int j;
+  unsigned int plt_got_offset, plt_entry_size;
+  asymbol *s;
+  bfd_byte *plt_contents;
+  long dynrelcount;
+  arelent **dynrelbuf, *p;
+  char *names;
+  const struct elf_backend_data *bed;
+  bfd_vma (*get_plt_got_vma) (struct elf_x86_plt *, bfd_vma, bfd_vma,
+			      bfd_vma);
+  bfd_boolean (*valid_plt_reloc_p) (unsigned int);
+
+  if (count == 0)
+    return -1;
+
+  dynrelbuf = (arelent **) bfd_malloc (relsize);
+  if (dynrelbuf == NULL)
+    return -1;
+
+  dynrelcount = bfd_canonicalize_dynamic_reloc (abfd, dynrelbuf,
+						dynsyms);
+
+  /* Sort the relocs by address.  */
+  qsort (dynrelbuf, dynrelcount, sizeof (arelent *),
+	 _bfd_x86_elf_compare_relocs);
+
+  size = count * sizeof (asymbol);
+
+  /* Allocate space for @plt suffixes.  */
+  n = 0;
+  for (i = 0; i < dynrelcount; i++)
+    {
+      p = dynrelbuf[i];
+      size += strlen ((*p->sym_ptr_ptr)->name) + sizeof ("@plt");
+      if (p->addend != 0)
+	size += sizeof ("+0x") - 1 + 8 + 8 * ABI_64_P (abfd);
+    }
+
+  s = *ret = (asymbol *) bfd_zmalloc (size);
+  if (s == NULL)
+    goto bad_return;
+
+  bed = get_elf_backend_data (abfd);
+
+  if (bed->target_id == X86_64_ELF_DATA)
+    {
+      get_plt_got_vma = elf_x86_64_get_plt_got_vma;
+      valid_plt_reloc_p = elf_x86_64_valid_plt_reloc_p;
+    }
+  else
+    {
+      get_plt_got_vma = elf_i386_get_plt_got_vma;
+      valid_plt_reloc_p = elf_i386_valid_plt_reloc_p;
+      if (got_addr)
+	{
+	  /* Check .got.plt and then .got to get the _GLOBAL_OFFSET_TABLE_
+	     address.  */
+	  asection *sec = bfd_get_section_by_name (abfd, ".got.plt");
+	  if (sec != NULL)
+	    got_addr = sec->vma;
+	  else
+	    {
+	      sec = bfd_get_section_by_name (abfd, ".got");
+	      if (sec != NULL)
+		got_addr = sec->vma;
+	    }
+
+	  if (got_addr == (bfd_vma) -1)
+	    goto bad_return;
+	}
+    }
+
+  /* Check for each PLT section.  */
+  names = (char *) (s + count);
+  size = 0;
+  n = 0;
+  for (j = 0; plts[j].name != NULL; j++)
+    if ((plt_contents = plts[j].contents) != NULL)
+      {
+	long k;
+	bfd_vma offset;
+	asection *plt;
+	struct elf_x86_plt *plt_p = &plts[j];
+
+	plt_got_offset = plt_p->plt_got_offset;
+	plt_entry_size = plt_p->plt_entry_size;
+
+	plt = plt_p->sec;
+
+	if ((plt_p->type & plt_lazy))
+	  {
+	    /* Skip PLT0 in lazy PLT.  */
+	    k = 1;
+	    offset = plt_entry_size;
+	  }
+	else
+	  {
+	    k = 0;
+	    offset = 0;
+	  }
+
+	/* Check each PLT entry against dynamic relocations.  */
+	for (; k < plt_p->count; k++)
+	  {
+	    int off;
+	    bfd_vma got_vma;
+	    long min, max, mid;
+
+	    /* Get the GOT offset for i386 or the PC-relative offset
+	       for x86-64, a signed 32-bit integer.  */
+	    off = H_GET_32 (abfd, (plt_contents + offset
+				   + plt_got_offset));
+	    got_vma = get_plt_got_vma (plt_p, off, offset, got_addr);
+
+	    /* Binary search.  */
+	    p = dynrelbuf[0];
+	    min = 0;
+	    max = dynrelcount;
+	    while ((min + 1) < max)
+	      {
+		arelent *r;
+
+		mid = (min + max) / 2;
+		r = dynrelbuf[mid];
+		if (got_vma > r->address)
+		  min = mid;
+		else if (got_vma < r->address)
+		  max = mid;
+		else
+		  {
+		    p = r;
+		    break;
+		  }
+	      }
+
+	    /* Skip unknown relocation.  PR 17512: file: bc9d6cf5.  */
+	    if (got_vma == p->address
+		&& p->howto != NULL
+		&& valid_plt_reloc_p (p->howto->type))
+	      {
+		*s = **p->sym_ptr_ptr;
+		/* Undefined syms won't have BSF_LOCAL or BSF_GLOBAL
+		   set.  Since we are defining a symbol, ensure one
+		   of them is set.  */
+		if ((s->flags & BSF_LOCAL) == 0)
+		  s->flags |= BSF_GLOBAL;
+		s->flags |= BSF_SYNTHETIC;
+		/* This is no longer a section symbol.  */
+		s->flags &= ~BSF_SECTION_SYM;
+		s->section = plt;
+		s->the_bfd = plt->owner;
+		s->value = offset;
+		s->udata.p = NULL;
+		s->name = names;
+		len = strlen ((*p->sym_ptr_ptr)->name);
+		memcpy (names, (*p->sym_ptr_ptr)->name, len);
+		names += len;
+		if (p->addend != 0)
+		  {
+		    char buf[30], *a;
+
+		    memcpy (names, "+0x", sizeof ("+0x") - 1);
+		    names += sizeof ("+0x") - 1;
+		    bfd_sprintf_vma (abfd, buf, p->addend);
+		    for (a = buf; *a == '0'; ++a)
+		      ;
+		    size = strlen (a);
+		    memcpy (names, a, size);
+		    names += size;
+		  }
+		memcpy (names, "@plt", sizeof ("@plt"));
+		names += sizeof ("@plt");
+		n++;
+		s++;
+	      }
+	    offset += plt_entry_size;
+	  }
+      }
+
+  /* PLT entries with R_386_TLS_DESC relocations are skipped.  */
+  if (n == 0)
+    {
+bad_return:
+      count = -1;
+    }
+  else
+    count = n;
+
+  for (j = 0; plts[j].name != NULL; j++)
+    if (plts[j].contents != NULL)
+      free (plts[j].contents);
+
+  free (dynrelbuf);
+
+  return count;
+}
+
 /* Parse x86 GNU properties.  */
 
 enum elf_property_kind