PR gold/12571

	* options.h (class General_options): Add
	--ld-generated-unwind-info.
	* ehframe.cc (Fde::write): Add address parameter.  Change all
	callers.  If associated with PLT, fill in address and size.
	(Cie::set_output_offset): Only add merge mapping if there is an
	object.
	(Cie::write): Add address parameter.  Change all callers.
	(Eh_frame::add_ehframe_for_plt): New function.
	* ehframe.h (class Fde): Update declarations.  Move shndx_ and
	input_offset_ fields into union u_, with new plt field.
	(Fde::Fde): Adjust for new union field.
	(Fde::Fde) [Output_data version]: New constructor.
	(Fde::add_mapping): Only add merge mapping if there is an object.
	(class Cie): Update declarations.
	(class Eh_frame): Declare add_ehframe_for_plt.
	* layout.cc (Layout::layout_eh_frame): Break out code into
	make_eh_frame_section, and call it.
	(Layout::make_eh_frame_section): New function.
	(Layout::add_eh_frame_for_plt): New function.
	* layout.h (class Layout): Update declarations.
	* merge.cc (Merge_map::add_mapping): Add assertion.
	* i386.cc: Include "dwarf.h".
	(class Output_data_plt_i386): Make first_plt_entry,
	dyn_first_plt_entry, exec_plt_entry, and dyn_plt_entry const.  Add
	plt_eh_frame_cie_size, plt_eh_frame_fde_size, plt_eh_frame_cie,
	and plt_eh_frame_fde.
	(Output_data_plt_i386::Output_data_plt_i386): Align to 16-byte
	boundary.  Call add_eh_frame_for_plt if appropriate.
	* x86_64.cc: Include "dwarf.h".
	(class Output_data_plt_x86_64): Align to 16-byte boundary.  Make
	first_plt_entry, plt_entry and tlsdesc_plt_entry const.  Add
	plt_eh_frame_cie_size, plt_eh_frame_fde_size, plt_eh_frame_cie,
	and plt_eh_frame_fde.
	(Output_data_plt_x86_64::init): Call add_eh_frame_for_plt if
	appropriate.

1 files changed, 60 insertions, 11 deletions

diff --git a/gold/ehframe.cc b/gold/ehframe.cc
index fbeb8a3..80b0035 100644
--- a/gold/ehframe.cc
+++ b/gold/ehframe.cc
@@ -1,6 +1,6 @@
 // ehframe.cc -- handle exception frame sections for gold
 
-// Copyright 2006, 2007, 2008, 2010 Free Software Foundation, Inc.
+// Copyright 2006, 2007, 2008, 2010, 2011 Free Software Foundation, Inc.
 // Written by Ian Lance Taylor <iant@google.com>.
 
 // This file is part of gold.
@@ -321,14 +321,16 @@ Eh_frame_hdr::get_fde_addresses(Output_file* of,
 
 // Write the FDE to OVIEW starting at OFFSET.  CIE_OFFSET is the
 // offset of the CIE in OVIEW.  FDE_ENCODING is the encoding, from the
-// CIE.  ADDRALIGN is the required alignment.  Record the FDE pc for
-// EH_FRAME_HDR.  Return the new offset.
+// CIE.  ADDRALIGN is the required alignment.  ADDRESS is the virtual
+// address of OVIEW.  Record the FDE pc for EH_FRAME_HDR.  Return the
+// new offset.
 
 template<int size, bool big_endian>
 section_offset_type
 Fde::write(unsigned char* oview, section_offset_type offset,
-	   unsigned int addralign, section_offset_type cie_offset,
-           unsigned char fde_encoding, Eh_frame_hdr* eh_frame_hdr)
+	   uint64_t address, unsigned int addralign,
+	   section_offset_type cie_offset, unsigned char fde_encoding,
+	   Eh_frame_hdr* eh_frame_hdr)
 {
   gold_assert((offset & (addralign - 1)) == 0);
 
@@ -355,6 +357,24 @@ Fde::write(unsigned char* oview, section_offset_type offset,
   // will later be applied to the FDE data.
   memcpy(oview + offset + 8, this->contents_.data(), length);
 
+  // If this FDE is associated with a PLT, fill in the PLT's address
+  // and size.
+  if (this->object_ == NULL)
+    {
+      gold_assert(memcmp(oview + offset + 8, "\0\0\0\0\0\0\0\0", 8) == 0);
+      Output_data* plt = this->u_.from_linker.plt;
+      uint64_t poffset = plt->address() - (address + offset + 8);
+      int32_t spoffset = static_cast<int32_t>(poffset);
+      off_t psize = plt->data_size();
+      uint32_t upsize = static_cast<uint32_t>(psize);
+      if (static_cast<uint64_t>(static_cast<int64_t>(spoffset)) != poffset
+	  || static_cast<off_t>(upsize) != psize)
+	gold_warning(_("overflow in PLT unwind data; "
+		       "unwinding through PLT may fail"));
+      elfcpp::Swap<32, big_endian>::writeval(oview + offset + 8, spoffset);
+      elfcpp::Swap<32, big_endian>::writeval(oview + offset + 12, upsize);
+    }
+
   if (aligned_full_length > length + 8)
     memset(oview + offset + length + 8, 0, aligned_full_length - (length + 8));
 
@@ -389,8 +409,12 @@ Cie::set_output_offset(section_offset_type output_offset,
   // Add 4 for length and 4 for zero CIE identifier tag.
   length += 8;
 
-  merge_map->add_mapping(this->object_, this->shndx_, this->input_offset_,
-			 length, output_offset);
+  if (this->object_ != NULL)
+    {
+      // Add a mapping so that relocations are applied correctly.
+      merge_map->add_mapping(this->object_, this->shndx_, this->input_offset_,
+			     length, output_offset);
+    }
 
   length = align_address(length, addralign);
 
@@ -415,7 +439,8 @@ Cie::set_output_offset(section_offset_type output_offset,
 template<int size, bool big_endian>
 section_offset_type
 Cie::write(unsigned char* oview, section_offset_type offset,
-	   unsigned int addralign, Eh_frame_hdr* eh_frame_hdr)
+	   uint64_t address, unsigned int addralign,
+	   Eh_frame_hdr* eh_frame_hdr)
 {
   gold_assert((offset & (addralign - 1)) == 0);
 
@@ -448,7 +473,7 @@ Cie::write(unsigned char* oview, section_offset_type offset,
   for (std::vector<Fde*>::const_iterator p = this->fdes_.begin();
        p != this->fdes_.end();
        ++p)
-    offset = (*p)->write<size, big_endian>(oview, offset, addralign,
+    offset = (*p)->write<size, big_endian>(oview, offset, address, addralign,
                                            cie_offset, fde_encoding,
                                            eh_frame_hdr);
 
@@ -994,6 +1019,29 @@ Eh_frame::read_fde(Sized_relobj_file<size, big_endian>* object,
   return true;
 }
 
+// Add unwind information for a PLT.
+
+void
+Eh_frame::add_ehframe_for_plt(Output_data* plt, const unsigned char* cie_data,
+			      size_t cie_length, const unsigned char* fde_data,
+			      size_t fde_length)
+{
+  Cie cie(NULL, 0, 0, elfcpp::DW_EH_PE_pcrel | elfcpp::DW_EH_PE_sdata4, "",
+	  cie_data, cie_length);
+  Cie_offsets::iterator find_cie = this->cie_offsets_.find(&cie);
+  Cie* pcie;
+  if (find_cie != this->cie_offsets_.end())
+    pcie = *find_cie;
+  else
+    {
+      pcie = new Cie(cie);
+      this->cie_offsets_.insert(pcie);
+    }
+
+  Fde* fde = new Fde(plt, fde_data, fde_length);
+  pcie->add_fde(fde);
+}
+
 // Return the number of FDEs.
 
 unsigned int
@@ -1113,18 +1161,19 @@ template<int size, bool big_endian>
 void
 Eh_frame::do_sized_write(unsigned char* oview)
 {
+  uint64_t address = this->address();
   unsigned int addralign = this->addralign();
   section_offset_type o = 0;
   for (Unmergeable_cie_offsets::iterator p =
 	 this->unmergeable_cie_offsets_.begin();
        p != this->unmergeable_cie_offsets_.end();
        ++p)
-    o = (*p)->write<size, big_endian>(oview, o, addralign,
+    o = (*p)->write<size, big_endian>(oview, o, address, addralign,
                                       this->eh_frame_hdr_);
   for (Cie_offsets::iterator p = this->cie_offsets_.begin();
        p != this->cie_offsets_.end();
        ++p)
-    o = (*p)->write<size, big_endian>(oview, o, addralign,
+    o = (*p)->write<size, big_endian>(oview, o, address, addralign,
                                       this->eh_frame_hdr_);
 }