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, 83 insertions, 44 deletions

diff --git a/gold/layout.cc b/gold/layout.cc
index 3152622..11dbbef 100644
--- a/gold/layout.cc
+++ b/gold/layout.cc
@@ -1136,51 +1136,10 @@ Layout::layout_eh_frame(Sized_relobj_file<size, big_endian>* object,
 	      || shdr.get_sh_type() == elfcpp::SHT_X86_64_UNWIND);
   gold_assert((shdr.get_sh_flags() & elfcpp::SHF_ALLOC) != 0);
 
-  const char* const name = ".eh_frame";
-  Output_section* os = this->choose_output_section(object, name,
-						   elfcpp::SHT_PROGBITS,
-						   elfcpp::SHF_ALLOC, false,
-						   ORDER_EHFRAME, false);
+  Output_section* os = this->make_eh_frame_section(object);
   if (os == NULL)
     return NULL;
 
-  if (this->eh_frame_section_ == NULL)
-    {
-      this->eh_frame_section_ = os;
-      this->eh_frame_data_ = new Eh_frame();
-
-      // For incremental linking, we do not optimize .eh_frame sections
-      // or create a .eh_frame_hdr section.
-      if (parameters->options().eh_frame_hdr() && !parameters->incremental())
-	{
-	  Output_section* hdr_os =
-	    this->choose_output_section(NULL, ".eh_frame_hdr",
-					elfcpp::SHT_PROGBITS,
-					elfcpp::SHF_ALLOC, false,
-					ORDER_EHFRAME, false);
-
-	  if (hdr_os != NULL)
-	    {
-	      Eh_frame_hdr* hdr_posd = new Eh_frame_hdr(os,
-							this->eh_frame_data_);
-	      hdr_os->add_output_section_data(hdr_posd);
-
-	      hdr_os->set_after_input_sections();
-
-	      if (!this->script_options_->saw_phdrs_clause())
-		{
-		  Output_segment* hdr_oseg;
-		  hdr_oseg = this->make_output_segment(elfcpp::PT_GNU_EH_FRAME,
-						       elfcpp::PF_R);
-		  hdr_oseg->add_output_section_to_nonload(hdr_os,
-							  elfcpp::PF_R);
-		}
-
-	      this->eh_frame_data_->set_eh_frame_hdr(hdr_posd);
-	    }
-	}
-    }
-
   gold_assert(this->eh_frame_section_ == os);
 
   elfcpp::Elf_Xword orig_flags = os->flags();
@@ -1222,8 +1181,8 @@ Layout::layout_eh_frame(Sized_relobj_file<size, big_endian>* object,
       // We couldn't handle this .eh_frame section for some reason.
       // Add it as a normal section.
       bool saw_sections_clause = this->script_options_->saw_sections_clause();
-      *off = os->add_input_section(this, object, shndx, name, shdr, reloc_shndx,
-				   saw_sections_clause);
+      *off = os->add_input_section(this, object, shndx, ".eh_frame", shdr,
+				   reloc_shndx, saw_sections_clause);
       this->have_added_input_section_ = true;
 
       if ((orig_flags & (elfcpp::SHF_WRITE | elfcpp::SHF_EXECINSTR))
@@ -1234,6 +1193,86 @@ Layout::layout_eh_frame(Sized_relobj_file<size, big_endian>* object,
   return os;
 }
 
+// Create and return the magic .eh_frame section.  Create
+// .eh_frame_hdr also if appropriate.  OBJECT is the object with the
+// input .eh_frame section; it may be NULL.
+
+Output_section*
+Layout::make_eh_frame_section(const Relobj* object)
+{
+  // FIXME: On x86_64, this could use SHT_X86_64_UNWIND rather than
+  // SHT_PROGBITS.
+  Output_section* os = this->choose_output_section(object, ".eh_frame",
+						   elfcpp::SHT_PROGBITS,
+						   elfcpp::SHF_ALLOC, false,
+						   ORDER_EHFRAME, false);
+  if (os == NULL)
+    return NULL;
+
+  if (this->eh_frame_section_ == NULL)
+    {
+      this->eh_frame_section_ = os;
+      this->eh_frame_data_ = new Eh_frame();
+
+      // For incremental linking, we do not optimize .eh_frame sections
+      // or create a .eh_frame_hdr section.
+      if (parameters->options().eh_frame_hdr() && !parameters->incremental())
+	{
+	  Output_section* hdr_os =
+	    this->choose_output_section(NULL, ".eh_frame_hdr",
+					elfcpp::SHT_PROGBITS,
+					elfcpp::SHF_ALLOC, false,
+					ORDER_EHFRAME, false);
+
+	  if (hdr_os != NULL)
+	    {
+	      Eh_frame_hdr* hdr_posd = new Eh_frame_hdr(os,
+							this->eh_frame_data_);
+	      hdr_os->add_output_section_data(hdr_posd);
+
+	      hdr_os->set_after_input_sections();
+
+	      if (!this->script_options_->saw_phdrs_clause())
+		{
+		  Output_segment* hdr_oseg;
+		  hdr_oseg = this->make_output_segment(elfcpp::PT_GNU_EH_FRAME,
+						       elfcpp::PF_R);
+		  hdr_oseg->add_output_section_to_nonload(hdr_os,
+							  elfcpp::PF_R);
+		}
+
+	      this->eh_frame_data_->set_eh_frame_hdr(hdr_posd);
+	    }
+	}
+    }
+
+  return os;
+}
+
+// Add an exception frame for a PLT.  This is called from target code.
+
+void
+Layout::add_eh_frame_for_plt(Output_data* plt, const unsigned char* cie_data,
+			     size_t cie_length, const unsigned char* fde_data,
+			     size_t fde_length)
+{
+  if (parameters->incremental())
+    {
+      // FIXME: Maybe this could work some day....
+      return;
+    }
+  Output_section* os = this->make_eh_frame_section(NULL);
+  if (os == NULL)
+    return;
+  this->eh_frame_data_->add_ehframe_for_plt(plt, cie_data, cie_length,
+					    fde_data, fde_length);
+  if (!this->added_eh_frame_data_)
+    {
+      os->add_output_section_data(this->eh_frame_data_);
+      this->added_eh_frame_data_ = true;
+    }
+}
+
 // Add POSD to an output section using NAME, TYPE, and FLAGS.  Return
 // the output section.