* elf-bfd.h (struct eh_cie_fde): Add set_loc pointer.

* elf-eh-frame.c (skip_cfa_op): Fix handling of DW_CFA_advance_loc. Handle DW_CFA_{remember,restore}_state, DW_CFA_GNU_window_save, DW_CFA_val_{offset{,_sf},expression}. (skip_non_nops): Record number of DW_CFA_set_loc ops. (_bfd_elf_discard_section_eh_frame): Require skip_non_nops recognizes all ops. If there are any DW_CFA_set_loc ops and they are pcrel or going to be pcrel, compute set_loc array. (_bfd_elf_eh_frame_section_offset): If make_relative, kill relocations against DW_CFA_set_loc operands. (_bfd_elf_write_section_eh_frame): Handle DW_CFA_set_loc adjusting. * ld-elf/eh4.d: New test. * ld-elf/eh4.s: New file. * ld-elf/eh4a.s: New file.
2006-10-03 13:15:39 +00:00 · 2006-10-03 13:15:39 +00:00 · ac685e6adf
parent 00479ba8f9
commit ac685e6adf
7 changed files with 243 additions and 7 deletions
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@ -1,3 +1,17 @@
+2006-10-03  Jakub Jelinek  <jakub@redhat.com>
+
+	* elf-bfd.h (struct eh_cie_fde): Add set_loc pointer.
+	* elf-eh-frame.c (skip_cfa_op): Fix handling of DW_CFA_advance_loc.
+	Handle DW_CFA_{remember,restore}_state, DW_CFA_GNU_window_save,
+	DW_CFA_val_{offset{,_sf},expression}.
+	(skip_non_nops): Record number of DW_CFA_set_loc ops.
+	(_bfd_elf_discard_section_eh_frame): Require skip_non_nops recognizes
+	all ops.  If there are any DW_CFA_set_loc ops and they are pcrel
+	or going to be pcrel, compute set_loc array.
+	(_bfd_elf_eh_frame_section_offset): If make_relative, kill relocations
+	against DW_CFA_set_loc operands.
+	(_bfd_elf_write_section_eh_frame): Handle DW_CFA_set_loc adjusting.
+
 2006-10-02  Daniel Jacobowitz  <dan@codesourcery.com>

 	* elflink.c (_bfd_elf_merge_symbol): Discard references to TLS
--- a/bfd/elf-bfd.h
+++ b/bfd/elf-bfd.h
@ -304,6 +304,7 @@ struct eh_cie_fde
  unsigned int make_lsda_relative : 1;
  unsigned int need_lsda_relative : 1;
  unsigned int per_encoding_relative : 1;
+  unsigned int *set_loc;
 };

 struct eh_frame_sec_info
--- a/bfd/elf-eh-frame.c
+++ b/bfd/elf-eh-frame.c
@ -273,11 +273,14 @@ skip_cfa_op (bfd_byte **iter, bfd_byte *end, unsigned int encoded_ptr_width)
  if (!read_byte (iter, end, &op))
    return FALSE;

-  switch (op & 0x80 ? op & 0xc0 : op)
+  switch (op & 0xc0 ? op & 0xc0 : op)
    {
    case DW_CFA_nop:
    case DW_CFA_advance_loc:
    case DW_CFA_restore:
+    case DW_CFA_remember_state:
+    case DW_CFA_restore_state:
+    case DW_CFA_GNU_window_save:
      /* No arguments.  */
      return TRUE;

@ -292,6 +295,8 @@ skip_cfa_op (bfd_byte **iter, bfd_byte *end, unsigned int encoded_ptr_width)
      /* One leb128 argument.  */
      return skip_leb128 (iter, end);

+    case DW_CFA_val_offset:
+    case DW_CFA_val_offset_sf:
    case DW_CFA_offset_extended:
    case DW_CFA_register:
    case DW_CFA_def_cfa:
@ -308,6 +313,7 @@ skip_cfa_op (bfd_byte **iter, bfd_byte *end, unsigned int encoded_ptr_width)
 	      && skip_bytes (iter, end, length));

    case DW_CFA_expression:
+    case DW_CFA_val_expression:
      /* A leb128 followed by a variable-length argument.  */
      return (skip_leb128 (iter, end)
 	      && read_uleb128 (iter, end, &length)
@ -339,7 +345,8 @@ skip_cfa_op (bfd_byte **iter, bfd_byte *end, unsigned int encoded_ptr_width)
   ENCODED_PTR_WIDTH is as for skip_cfa_op.  */

 static bfd_byte *
-skip_non_nops (bfd_byte *buf, bfd_byte *end, unsigned int encoded_ptr_width)
+skip_non_nops (bfd_byte *buf, bfd_byte *end, unsigned int encoded_ptr_width,
+	       unsigned int *set_loc_count)
 {
  bfd_byte *last;

@ -349,6 +356,8 @@ skip_non_nops (bfd_byte *buf, bfd_byte *end, unsigned int encoded_ptr_width)
      buf++;
    else
      {
+	if (*buf == DW_CFA_set_loc)
+	  ++*set_loc_count;
 	if (!skip_cfa_op (&buf, end, encoded_ptr_width))
 	  return 0;
 	last = buf;
@ -453,8 +462,9 @@ _bfd_elf_discard_section_eh_frame
  for (;;)
    {
      char *aug;
-      bfd_byte *start, *end, *insns;
+      bfd_byte *start, *end, *insns, *insns_end;
      bfd_size_type length;
+      unsigned int set_loc_count;

      if (sec_info->count == sec_info->alloced)
 	{
@ -558,6 +568,7 @@ _bfd_elf_discard_section_eh_frame
 	  cie_usage_count = 0;
 	  memset (&cie, 0, sizeof (cie));
 	  cie.hdr = hdr;
+	  start = buf;
 	  REQUIRE (read_byte (&buf, end, &cie.version));

 	  /* Cannot handle unknown versions.  */
@ -775,11 +786,38 @@ _bfd_elf_discard_section_eh_frame

      /* Try to interpret the CFA instructions and find the first
 	 padding nop.  Shrink this_inf's size so that it doesn't
-	 including the padding.  */
+	 include the padding.  */
      length = get_DW_EH_PE_width (cie.fde_encoding, ptr_size);
-      insns = skip_non_nops (insns, end, length);
-      if (insns != 0)
-	this_inf->size -= end - insns;
+      set_loc_count = 0;
+      insns_end = skip_non_nops (insns, end, length, &set_loc_count);
+      /* If we don't understand the CFA instructions, we can't know
+	 what needs to be adjusted there.  */
+      if (insns_end == NULL
+	  /* For the time being we don't support DW_CFA_set_loc in
+	     CIE instructions.  */
+	  || (set_loc_count && this_inf->cie))
+	goto free_no_table;
+      this_inf->size -= end - insns_end;
+      if (set_loc_count
+	  && ((cie.fde_encoding & 0xf0) == DW_EH_PE_pcrel
+	      || cie.make_relative))
+	{
+	  unsigned int cnt;
+	  bfd_byte *p;
+
+	  this_inf->set_loc = bfd_malloc ((set_loc_count + 1)
+					  * sizeof (unsigned int));
+	  REQUIRE (this_inf->set_loc);
+	  this_inf->set_loc[0] = set_loc_count;
+	  p = insns;
+	  cnt = 0;
+	  while (p < end)
+	    {
+	      if (*p == DW_CFA_set_loc)
+		this_inf->set_loc[++cnt] = p + 1 - start;
+	      REQUIRE (skip_cfa_op (&p, end, length));
+	    }
+	}

      this_inf->fde_encoding = cie.fde_encoding;
      this_inf->lsda_encoding = cie.lsda_encoding;
@ -965,6 +1003,23 @@ _bfd_elf_eh_frame_section_offset (bfd *output_bfd ATTRIBUTE_UNUSED,
      return (bfd_vma) -2;
    }

+  /* If converting to DW_EH_PE_pcrel, there will be no need for run-time
+     relocation against DW_CFA_set_loc's arguments.  */
+  if (sec_info->entry[mid].set_loc
+      && (sec_info->entry[mid].cie
+	  ? sec_info->entry[mid].make_relative
+	  : sec_info->entry[mid].cie_inf->make_relative)
+      && (offset >= sec_info->entry[mid].offset + 8
+		    + sec_info->entry[mid].set_loc[1]))
+    {
+      unsigned int cnt;
+
+      for (cnt = 1; cnt <= sec_info->entry[mid].set_loc[0]; cnt++)
+	if (offset == sec_info->entry[mid].offset + 8
+		      + sec_info->entry[mid].set_loc[cnt])
+	  return (bfd_vma) -2;
+    }
+
  if (hdr_info->offsets_adjusted)
    offset -= sec->output_offset;
  /* Any new augmentation bytes go before the first relocation.  */
@ -1189,6 +1244,7 @@ _bfd_elf_write_section_eh_frame (bfd *abfd,
 	  /* FDE */
 	  bfd_vma value, address;
 	  unsigned int width;
+	  bfd_byte *start;

 	  /* Skip length.  */
 	  buf += 4;
@ -1225,6 +1281,8 @@ _bfd_elf_write_section_eh_frame (bfd *abfd,
 	      write_value (abfd, buf, value, width);
 	    }

+	  start = buf;
+
 	  if (hdr_info)
 	    {
 	      hdr_info->array[hdr_info->array_count].initial_loc = address;
@ -1257,6 +1315,36 @@ _bfd_elf_write_section_eh_frame (bfd *abfd,
 	      memmove (buf + 1, buf, end - buf);
 	      *buf = 0;
 	    }
+
+	  if (ent->set_loc)
+	    {
+	      /* Adjust DW_CFA_set_loc.  */
+	      unsigned int cnt, width;
+	      bfd_vma new_offset;
+
+	      width = get_DW_EH_PE_width (ent->fde_encoding, ptr_size);
+	      new_offset = ent->new_offset + 8
+			   + extra_augmentation_string_bytes (ent)
+			   + extra_augmentation_data_bytes (ent);
+
+	      for (cnt = 1; cnt <= ent->set_loc[0]; cnt++)
+		{
+		  bfd_vma value;
+		  buf = start + ent->set_loc[cnt];
+
+		  value = read_value (abfd, buf, width,
+				      get_DW_EH_PE_signed (ent->fde_encoding));
+		  if (!value)
+		    continue;
+
+		  if ((ent->fde_encoding & 0xf0) == DW_EH_PE_pcrel)
+		    value += ent->offset + 8 - new_offset;
+		  if (ent->cie_inf->make_relative)
+		    value -= sec->output_section->vma + new_offset
+			     + ent->set_loc[cnt];
+		  write_value (abfd, buf, value, width);
+		}
+	    }
 	}
    }

--- a/ld/testsuite/ChangeLog
+++ b/ld/testsuite/ChangeLog
@ -1,3 +1,9 @@
+2006-10-03  Jakub Jelinek  <jakub@redhat.com>
+
+	* ld-elf/eh4.d: New test.
+	* ld-elf/eh4.s: New file.
+	* ld-elf/eh4a.s: New file.
+
 2006-10-02  Vladimir Prus  <vladimir@codesourcery.com>

 	* ld-arm/use-thumb-lib.sym: Robustify, by ignoring symbols we're
--- a/ld/testsuite/ld-elf/eh4.d
+++ b/ld/testsuite/ld-elf/eh4.d
@ -0,0 +1,32 @@
+#source: eh4.s
+#source: eh4a.s
+#ld: -shared
+#readelf: -wf
+#target: x86_64-*-*
+
+The section .eh_frame contains:
+
+00000000 00000014 00000000 CIE
+  Version:               1
+  Augmentation:          "zR"
+  Code alignment factor: 1
+  Data alignment factor: -8
+  Return address column: 16
+  Augmentation data:     1b
+
+  DW_CFA_def_cfa: r7 ofs 8
+  DW_CFA_offset: r16 at cfa-8
+  DW_CFA_nop
+  DW_CFA_nop
+
+00000018 00000014 0000001c FDE cie=00000000 pc=00000400..00000413
+  DW_CFA_set_loc: 00000404
+  DW_CFA_def_cfa_offset: 80
+
+00000030 00000014 00000034 FDE cie=00000000 pc=00000413..00000426
+  DW_CFA_set_loc: 00000417
+  DW_CFA_def_cfa_offset: 80
+
+00000048 ZERO terminator
+#pass
+
--- a/ld/testsuite/ld-elf/eh4.s
+++ b/ld/testsuite/ld-elf/eh4.s
@ -0,0 +1,92 @@
+	.text
+	.align	512
+	.globl foo
+	.type	foo, @function
+foo:
+.LFB1:
+	subq	$72, %rsp
+.LCFI1:
+	xorl	%eax, %eax
+	movq	%rsp, %rdi
+	call	bar@PLT
+	addq	$72, %rsp
+	ret
+.LFE1:
+	.size	foo, .-foo
+	.globl bar
+	.type	bar, @function
+bar:
+.LFB2:
+	subq	$72, %rsp
+.LCFI2:
+	xorl	%eax, %eax
+	movq	%rsp, %rdi
+	call	bar@PLT
+	addq	$72, %rsp
+	ret
+.LFE2:
+	.size	bar, .-bar
+	.section	.eh_frame,"a",@progbits
+.Lframe1:
+	.long	.LECIE1-.LSCIE1	# Length of Common Information Entry
+.LSCIE1:
+	.long	0x0	# CIE Identifier Tag
+	.byte	0x1	# CIE Version
+	.ascii "zR\0"	# CIE Augmentation
+	.uleb128 0x1	# CIE Code Alignment Factor
+	.sleb128 -8	# CIE Data Alignment Factor
+	.byte	0x10	# CIE RA Column
+	.uleb128 0x1	# Augmentation size
+	.byte	0x1b	# FDE Encoding (pcrel sdata4)
+	.byte	0xc	# DW_CFA_def_cfa
+	.uleb128 0x7
+	.uleb128 0x8
+	.byte	0x90	# DW_CFA_offset, column 0x10
+	.uleb128 0x1
+	.align 8
+.LECIE1:
+.LSFDE1:
+	.long	.LEFDE1-.LASFDE1	# FDE Length
+.LASFDE1:
+	.long	.LASFDE1-.Lframe1	# FDE CIE offset
+	.long	.LFB1-.	# FDE initial location
+	.long	.LFE1-.LFB1	# FDE address range
+	.uleb128 0x0	# Augmentation size
+	.byte	0x1	# DW_CFA_set_loc
+	.long	.LCFI1-.
+	.byte	0xe	# DW_CFA_def_cfa_offset
+	.uleb128 0x50
+	.align 8
+.LEFDE1:
+.Lframe2:
+	.long	.LECIE2-.LSCIE2	# Length of Common Information Entry
+.LSCIE2:
+	.long	0x0	# CIE Identifier Tag
+	.byte	0x1	# CIE Version
+	.ascii "zR\0"	# CIE Augmentation
+	.uleb128 0x1	# CIE Code Alignment Factor
+	.sleb128 -8	# CIE Data Alignment Factor
+	.byte	0x10	# CIE RA Column
+	.uleb128 0x1	# Augmentation size
+	.byte	0x1b	# FDE Encoding (pcrel sdata4)
+	.byte	0xc	# DW_CFA_def_cfa
+	.uleb128 0x7
+	.uleb128 0x8
+	.byte	0x90	# DW_CFA_offset, column 0x10
+	.uleb128 0x1
+	.align 8
+.LECIE2:
+.LSFDE2:
+	.long	.LEFDE2-.LASFDE2	# FDE Length
+.LASFDE2:
+	.long	.LASFDE2-.Lframe2	# FDE CIE offset
+	.long	.LFB2-.	# FDE initial location
+	.long	.LFE2-.LFB2	# FDE address range
+	.uleb128 0x0	# Augmentation size
+	.byte	0x1	# DW_CFA_set_loc
+	.long	.LCFI2-.
+	.byte	0xe	# DW_CFA_def_cfa_offset
+	.uleb128 0x50
+	.align 8
+.LEFDE2:
+	.section	.note.GNU-stack,"",@progbits
--- a/ld/testsuite/ld-elf/eh4a.s
+++ b/ld/testsuite/ld-elf/eh4a.s
@ -0,0 +1,3 @@
+	.section	.eh_frame,"a",%progbits
+	.align	8
+	.zero	8