Compact EH Support

The specification for the Compact EH format is available at:
https://github.com/MentorEmbedded/cxx-abi/blob/master/MIPSCompactEH.pdf

2015-05-28  Catherine Moore  <clm@codesourcery.com>
	    Bernd Schmidt <bernds@codesourcery.com>
	    Paul Brook <paul@codesourcery.com>

	bfd/
	* bfd-in2.h: Regenerated.
	* elf-bfd.h (DWARF2_EH_HDR, COMPACT_EH_HDR): Define.
	(COMPACT_EH_CANT_UNWIND_OPCODE): Define.
	(dwarf_eh_frame_hdr_info): Move dwarf-specific fields from
	eh_frame_hdr_info.
	(compact_eh_frame_hdr_info): Declare.
	(eh_frame_hdr_info):  Redeclare with union for dwarf-specific
	fields and compact-eh fields.
	(elf_backend_data): Add cant_unwind_opcode and compact_eh_encoding.
	(bfd_elf_section_data): Add eh_frame_entry_field.
	(elf_section_eh_frame_entry): Define.
	(bfd_elf_parse_eh_frame_entries): Declare.
	(_bfd_elf_parse_eh_frame_entry): Declare.
	(_bfd_elf_end_eh_frame_parsing): Declare.
	(_bfd_elf_write_section_eh_frame_entry): Declare.
	(_bfd_elf_eh_frame_entry_present): Declare.
	(_bfd_elf_section_for_symbol): Declare.
	* elf-eh-frame.c (bfd_elf_discard_eh_frame_entry): New function.
	(bfd_elf_record_eh_frame_entry): New function.
	(_bfd_elf_parse_eh_frame_entry): New function.
	(_bfd_elf_parse_eh_frame): Update hdr_info field references.
	(cmp_eh_frame_hdr): New function.
	(add_eh_frame_hdr_terminator): New function.
	(_bfd_elf_end_eh_frame_parsing): New function.
	(find_merged_cie): Update hdr_info field references.
	(_bfd_elf_discard_section_eh_frame): Likewise.
	(_bfd_elf_discard_section_eh_frame_hdr): Add Compact EH support.
	(_bfd_elf_eh_frame_entry_present): New function.
	(_bfd_elf_maybe_strip_eh_frame_hdr): Add Compact EH support.
	(_bfd_elf_write_section_eh_frame_entry): New function.
	(_bfd_elf_write_section_eh_frame): Update hdr_info field references.
	(_bfd_elf_fixup_eh_frame_hdr): New function.
	(write_compact_eh_frame_hdr): New function.
	(write_dwarf_eh_frame_hdr): New function.
	(_bfd_elf_write_section_eh_frame_hdr): Add Compact EH support.
	* elflink.c (_bfd_elf_section_for_symbol): New function.
	(elf_section_ignore_discarded_relocs): Add Compact EH support.
	(elf_link_input_bfd): Likewise.
	(bfd_elf_final_link): Likewise.
	(_bfd_elf_gc_mark): Likewise.
	(bfd_elf_parse_eh_frame_entries): New function.
	(bfd_elf_gc_sections): Add Compact EH support.
	(bfd_elf_discard_info): Likewise.
	* elfxx-mips.c: Include dwarf2.h.
	(_bfd_mips_elf_compact_eh_encoding): New function.
	(_bfd_mips_elf_cant_unwind_opcode): New function.
	* elfxx-mips.h (_bfd_mips_elf_compact_eh_encoding): Declare.
	(_bfd_mips_elf_cant_unwind_opcode): Declare.
	(elf_backend_compact_eh_encoding): Define.
	(elf_backend_cant_unwind_opcode): Define.
	* elfxx-target.h (elf_backend_compact_eh_encoding): Provide default.
	(elf_backend_cant_unwind_opcode): Provide default.
	(elf_backend_data elfNN_bed): Add elf_backend_compact_eh_encoding and
	elf_backend_cant_unwind_opcode.
	* section.c (SEC_INFO_TYPE_EH_FRAME_ENTRY): Add definition.

	gas/
	* config/tc-alpha.c (all_cfi_sections): Declare.
	(s_alpha_ent): Initialize all_cfi_sections.
	(alpha_elf_md_end): Invoke cfi_set_sections.
	* config/tc-mips.c (md_apply_fix):  Handle BFD_RELOC_NONE.
	(s_ehword): Use BFD_RELOC_32_PCREL.
	(mips_fix_adjustable): Handle BFD_RELOC_32_PCREL.
	(mips_cfi_reloc_for_encoding): New function.
	* tc-mips.h (DWARF2_FDE_RELOC_SIZE): Redefine.
	(DWARF2_FDE_RELOC_ENCODING): Define.
	(tc_cfi_reloc_for_encoding): Define.
	(mips_cfi_reloc_for_encoding): Define.
	(tc_compact_eh_opcode_stop): Define.
	(tc_compact_eh_opcode_pad): Define.
	* doc/as.texinfo: Document Compact EH extensions.
	* doc/internals.texi: Likewise.
	* dw2gencfi.c (EH_FRAME_LINKONCE): Redefine.
	(tc_cfi_reloc_for_encoding): Provide default.
	(compact_eh): Declare.
	(emit_expr_encoded): New function.
	(get_debugseg_name): Add Compact EH support.
	(alloc_debugseg_item): Likewise.
	(cfi_set_sections): New function.
	(dot_cfi_fde_data): New function.
	(dot_cfi_personality_id): New function.
	(dot_cfi_inline_lsda): New function.
	(cfi_pseudo_table): Add cfi_fde_data, cfi_personality_id,
	and cfi_inline_lsda.
	(dot_cfi_personality): Add Compact EH support.
	(dot_cfi_lsda): Likewise.
	(dot_cfi_sections): Likewise.
	(dot_cfi_startproc): Likewise.
	(get_cfi_seg): Likewise.
	(output_compact_unwind_data): New function.
	(output_cfi_insn): Add Compact EH support.
	(output_cie): Likewise.
	(output_fde): Likewise.
	(cfi_finish): Likewise.
	(cfi_emit_eh_header): New function.
	(output_eh_header): New function.
	* dw2gencfi.h (cfi_set_sections): Declare.
	(SUPPORT_COMPACT_EH): Define.
	(MULTIPLE_FRAME_SECTIONS): Define.
	New enumeration to describe the Compact EH header format.
	(fde_entry): Add new fields personality_id, eh_header_type, eh_data_size,
	eh_data, eh_loc and sections.
	(CFI_EMIT_eh_frame, CFI_EMIT_debug_frame, CFI_EMIT_target,
	CFI_EMIT_eh_frame_compact): Define.

2015-05-22  Catherine Moore  <clm@codesourcery.com>
	    Bernd Schmidt <bernds@codesourcery.com>

	gas/testsuite/
	* gas/mips/mips.exp: Run new tests.

	* gas/mips/compact-eh-1.s: New file.
	* gas/mips/compact-eh-2.s: New file.
	* gas/mips/compact-eh-3.s: New file.
	* gas/mips/compact-eh-4.s: New file.
	* gas/mips/compact-eh-5.s: New file.
	* gas/mips/compact-eh-6.s: New file.
	* gas/mips/compact-eh-7.s: New file.
	* gas/mips/compact-eh-eb-1.d: New file.
	* gas/mips/compact-eh-eb-2.d: New file.
	* gas/mips/compact-eh-eb-3.d: New file.
	* gas/mips/compact-eh-eb-4.d: New file.
	* gas/mips/compact-eh-eb-5.d: New file.
	* gas/mips/compact-eh-eb-6.d: New file.
	* gas/mips/compact-eh-eb-7.d: New file.
	* gas/mips/compact-eh-el-1.d: New file.
	* gas/mips/compact-eh-el-2.d: New file.
	* gas/mips/compact-eh-el-3.d: New file.
	* gas/mips/compact-eh-el-4.d: New file.
	* gas/mips/compact-eh-el-5.d: New file.
	* gas/mips/compact-eh-el-6.d: New file.
	* gas/mips/compact-eh-el-7.d: New file.
	* gas/mips/compact-eh-err1.l: New file.
	* gas/mips/compact-eh-err1.s: New file.
	* gas/mips/compact-eh-err2.l: New file.
	* gas/mips/compact-eh-err2.s: New file.

2015-05-22  Catherine Moore  <clm@codesourcery.com>

	include/
	* bfdlink.h: Rename eh_frame_hdr to eh_frame_hdr_type.

2015-05-22  Catherine Moore  <clm@codesourcery.com>
	    Paul Brook <paul@codesourcery.com>

	ld/
	* emultempl/elf32.em (gld${EMULATION_NAME}_after_open):
	Add Compact EH support.
	* scripttempl/elf.sc: Handle .eh_frame_entry and .gnu_extab
	sections.

2015-05-22  Catherine Moore  <clm@codesourcery.com>

	ld/testsuite/
	* ld-mips-elf/compact-eh.ld: New linker script.
	* ld-mips-elf/compact-eh1.d: New.
	* ld-mips-elf/compact-eh1.s: New.
	* ld-mips-elf/compact-eh1a.s: New.
	* ld-mips-elf/compact-eh1b.s: New.
	* ld-mips-elf/compact-eh2.d: New.
	* ld-mips-elf/compact-eh2.s: New.
	* ld-mips-elf/compact-eh3.d: New.
	* ld-mips-elf/compact-eh3.s: New.
	* ld-mips-elf/compact-eh3a.s: New.
	* ld-mips-elf/compact-eh4.d: New.
	* ld-mips-elf/compact-eh5.d: New.
	* ld-mips-elf/compact-eh6.d: New.
	* ld-mips-elf/mips-elf.exp: Run new tests.

9 files changed, 878 insertions, 116 deletions

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index a8a0ad9..48a3228 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,64 @@
+2015-05-28  Catherine Moore  <clm@codesourcery.com>
+	    Bernd Schmidt <bernds@codesourcery.com>
+	    Paul Brook <paul@codesourcery.com>
+
+	bfd/
+	* bfd-in2.h: Regenerated.
+	* elf-bfd.h (DWARF2_EH_HDR, COMPACT_EH_HDR): Define.
+	(COMPACT_EH_CANT_UNWIND_OPCODE): Define.
+	(dwarf_eh_frame_hdr_info): Move dwarf-specific fields from
+	eh_frame_hdr_info.
+	(compact_eh_frame_hdr_info): Declare.
+	(eh_frame_hdr_info):  Redeclare with union for dwarf-specific
+	fields and compact-eh fields.
+	(elf_backend_data): Add cant_unwind_opcode and compact_eh_encoding.
+	(bfd_elf_section_data): Add eh_frame_entry_field.
+	(elf_section_eh_frame_entry): Define.
+	(bfd_elf_parse_eh_frame_entries): Declare.
+	(_bfd_elf_parse_eh_frame_entry): Declare.
+	(_bfd_elf_end_eh_frame_parsing): Declare.
+	(_bfd_elf_write_section_eh_frame_entry): Declare.
+	(_bfd_elf_eh_frame_entry_present): Declare.
+	(_bfd_elf_section_for_symbol): Declare.
+	* elf-eh-frame.c (bfd_elf_discard_eh_frame_entry): New function.
+	(bfd_elf_record_eh_frame_entry): New function.
+	(_bfd_elf_parse_eh_frame_entry): New function.
+	(_bfd_elf_parse_eh_frame): Update hdr_info field references.
+	(cmp_eh_frame_hdr): New function.
+	(add_eh_frame_hdr_terminator): New function.
+	(_bfd_elf_end_eh_frame_parsing): New function.
+	(find_merged_cie): Update hdr_info field references.
+	(_bfd_elf_discard_section_eh_frame): Likewise.
+	(_bfd_elf_discard_section_eh_frame_hdr): Add Compact EH support.
+	(_bfd_elf_eh_frame_entry_present): New function.
+	(_bfd_elf_maybe_strip_eh_frame_hdr): Add Compact EH support.
+	(_bfd_elf_write_section_eh_frame_entry): New function.
+	(_bfd_elf_write_section_eh_frame): Update hdr_info field references.
+	(_bfd_elf_fixup_eh_frame_hdr): New function.
+	(write_compact_eh_frame_hdr): New function.
+	(write_dwarf_eh_frame_hdr): New function.
+	(_bfd_elf_write_section_eh_frame_hdr): Add Compact EH support.
+	* elflink.c (_bfd_elf_section_for_symbol): New function.
+	(elf_section_ignore_discarded_relocs): Add Compact EH support.
+	(elf_link_input_bfd): Likewise.
+	(bfd_elf_final_link): Likewise.
+	(_bfd_elf_gc_mark): Likewise.
+	(bfd_elf_parse_eh_frame_entries): New function.
+	(bfd_elf_gc_sections): Add Compact EH support.
+	(bfd_elf_discard_info): Likewise.
+	* elfxx-mips.c: Include dwarf2.h.
+	(_bfd_mips_elf_compact_eh_encoding): New function.
+	(_bfd_mips_elf_cant_unwind_opcode): New function.
+	* elfxx-mips.h (_bfd_mips_elf_compact_eh_encoding): Declare.
+	(_bfd_mips_elf_cant_unwind_opcode): Declare.
+	(elf_backend_compact_eh_encoding): Define.
+	(elf_backend_cant_unwind_opcode): Define.
+	* elfxx-target.h (elf_backend_compact_eh_encoding): Provide default.
+	(elf_backend_cant_unwind_opcode): Provide default.
+	(elf_backend_data elfNN_bed): Add elf_backend_compact_eh_encoding and
+	elf_backend_cant_unwind_opcode.
+	* section.c (SEC_INFO_TYPE_EH_FRAME_ENTRY): Add definition.
+
 2015-05-27  H.J. Lu  <hongjiu.lu@intel.com>
 
 	PR binutils/18458
@@ -229,6 +290,77 @@
 	* elf64-ppc.c (TOC_BASE_ALIGN): Define.
 	(ppc64_elf_next_toc_section): Align multi-got toc base.
 	(ppc64_elf_set_toc): Likewise initial toc base and .TOC. symbol.
+=======
+2015-05-04  Catherine Moore  <clm@codesourcery.com>
+
+	* elfxx-target.h: Add missing #endif.
+
+2015-04-22  Catherine Moore  <clm@codesourcery.com>
+
+	* elf-eh-frame.c (_bfd_elf_write_section_eh_frame_entry):  Don't write
+	the .eh_frame_entry section if the corresponding text section is marked
+	with SEC_EXCLUDE.
+
+2015-04-22  Catherine Moore  <clm@codesourcery.com>
+	    Bernd Schmidt <bernds@codesourcery.com>
+	    Paul Brook <paul@codesourcery.com>
+
+	* bfd-in2.h (SEC_INFO_TYPE_EH_FRAME_ENTRY): Define.
+	* elf-bfd.h (DWARF2_EH_HDR, COMPACT_EH_HDR): Define.
+	(COMPACT_EH_CANT_UNWIND_OPCODE): Define.
+	(dwarf_eh_frame_hdr_info): New struct.
+	(compact_eh_frame_hdr_info): New struct.
+	(eh_frame_hdr_info): Separate dwarf and compact fields.
+	(elf_backend_data): Add compact_eh_encoding and cant_unwind_opcode
+	fields.
+	(bfd_elf_section_data): Add eh_frame_entry field.
+	(elf_section_eh_frame_entry): Define.
+	(bfd_elf_parse_eh_frame_entries): Declare.
+	(_bfd_elf_parse_eh_frame_entry): Declare.
+	(_bfd_elf_end_eh_frame_parsing): Declare.
+	(_bfd_elf_write_section_eh_frame_entry): Declare.
+	(_bfd_elf_fixup_eh_frame_hdr): Declare.
+	(_bfd_elf_eh_frame_entry_present): Declare.
+	(_bfd_elf_section_for_symbol): Declare.
+	* elf-eh-frame.c (bfd_elf_discard_eh_frame_entry): New function.
+	(bfd_elf_record_eh_frame_entry): New function.
+	(_bfd_elf_parse_eh_frame_entry): New function.
+	(_bfd_elf_parse_eh_frame): Update hdr_info field references.
+	(cmp_eh_frame_hdr): New function.
+	(add_eh_frame_hdr_terminator): New function.
+	(_bfd_elf_end_eh_frame_parsing): New function.
+	(find_merged_cie): Update hdr_info field references.
+	(_bfd_elf_discard_section_eh_frame): Likewise.
+	(_bfd_elf_discard_section_eh_frame_hdr): Likewise.
+	Add Compact EH support.
+	(_bfd_elf_eh_frame_entry_present): New function.
+	(_bfd_elf_maybe_strip_eh_frame_hdr): Add Compact EH support.
+	(_bfd_elf_write_section_eh_frame_entry): New function.
+	(_bfd_elf_write_section_eh_frame): Update hdr_info field references.
+	(_bfd_elf_write_section_eh_frame): Likewise.
+	(_bfd_elf_fixup_eh_frame_hdr): New function.
+	(write_compact_eh_frame_hdr): New function.
+	(_bfd_elf_write_section_eh_frame_hdr): Compact EH support.  Update
+	hdr_info field references.
+	* elflink.c (_bfd_elf_section_for_symbol): New function.
+	(elf_section_ignore_discarded_relocs, elf_link_input_bfd):
+	Handle SEC_INFO_TYPE_EH_FRAME_ENTRY.
+	(bfd_elf_final_link): Call _bfd_elf_fixup_eh_frame_hdr.
+	(_bfd_elf_gc_mark):  Support Compact EH.
+	(bfd_elf_parse_eh_frame_entries): New function.
+	(bfd_elf_gc_sections): Support Compact EH.
+	(bfd_elf_discard_info): Likewise.
+	* elfxx-mips.c (_bfd_mips_elf_compact_eh_encoding): New function.
+	(_bfd_mips_elf_cant_unwind_opcode): New function.
+	* elfxx-mips.h (_bfd_mips_elf_compact_eh_encoding): Declare.
+	(_bfd_mips_elf_cant_unwind_opcode): Declare.
+	(elf_backend_compact_eh_encoding): Define.
+	(elf_backend_cant_unwind_opcode): Define.
+	* elfxx-target.h (elf_backend_compact_eh_encoding):
+	Provide default definition.
+	(elf_backend_cant_unwind_opcode): Provide default definition.
+	* section.c (SEC_INFO_TYPE_EH_FRAME_ENTRY): Define.
+>>>>>>> 2015-05-04  Catherine Moore  <clm@codesourcery.com>
 
 2015-04-22  H.J. Lu  <hongjiu.lu@intel.com>
 
diff --git a/bfd/bfd-in2.h b/bfd/bfd-in2.h
index 6f7ae34..ee67340 100644
--- a/bfd/bfd-in2.h
+++ b/bfd/bfd-in2.h
@@ -1452,6 +1452,7 @@ typedef struct bfd_section
 #define SEC_INFO_TYPE_EH_FRAME  3
 #define SEC_INFO_TYPE_JUST_SYMS 4
 #define SEC_INFO_TYPE_TARGET    5
+#define SEC_INFO_TYPE_EH_FRAME_ENTRY 6
 
   /* Nonzero if this section uses RELA relocations, rather than REL.  */
   unsigned int use_rela_p:1;
diff --git a/bfd/elf-bfd.h b/bfd/elf-bfd.h
index e435e52..9807fe7 100644
--- a/bfd/elf-bfd.h
+++ b/bfd/elf-bfd.h
@@ -388,16 +388,41 @@ struct eh_frame_array_ent
 
 struct htab;
 
-struct eh_frame_hdr_info
+#define DWARF2_EH_HDR 1
+#define COMPACT_EH_HDR 2
+
+/* Endian-neutral code indicating that a function cannot be unwound.  */
+#define COMPACT_EH_CANT_UNWIND_OPCODE 0x015d5d01
+
+struct dwarf_eh_frame_hdr_info
 {
   struct htab *cies;
-  asection *hdr_sec;
-  unsigned int fde_count, array_count;
-  struct eh_frame_array_ent *array;
+  unsigned int fde_count;
   /* TRUE if .eh_frame_hdr should contain the sorted search table.
      We build it if we successfully read all .eh_frame input sections
      and recognize them.  */
   bfd_boolean table;
+  struct eh_frame_array_ent *array;
+};
+
+struct compact_eh_frame_hdr_info
+{
+  unsigned int allocated_entries;
+  /* eh_frame_entry fragments.  */
+  asection **entries;
+};
+
+struct eh_frame_hdr_info
+{
+  asection *hdr_sec;
+  unsigned int array_count;
+  bfd_boolean frame_hdr_is_compact;
+  union
+    {
+      struct dwarf_eh_frame_hdr_info dwarf;
+      struct compact_eh_frame_hdr_info compact;
+    }
+  u;
 };
 
 /* Enum used to identify target specific extensions to the elf_obj_tdata
@@ -1291,6 +1316,12 @@ struct elf_backend_data
      or give an error and return FALSE.  */
   bfd_boolean (*obj_attrs_handle_unknown) (bfd *, int);
 
+  /* Encoding used for compact EH tables.  */
+  int (*compact_eh_encoding) (struct bfd_link_info *);
+
+  /* Opcode representing no unwind.  */
+  int (*cant_unwind_opcode) (struct bfd_link_info *);
+
   /* This is non-zero if static TLS segments require a special alignment.  */
   unsigned static_tls_alignment;
 
@@ -1445,6 +1476,9 @@ struct bfd_elf_section_data
      field acts as a chain pointer.  */
   struct eh_cie_fde *fde_list;
 
+  /* Link from a text section to its .eh_frame_entry section.  */
+  asection *eh_frame_entry;
+
   /* A pointer used for various section optimizations.  */
   void *sec_info;
 };
@@ -1458,6 +1492,7 @@ struct bfd_elf_section_data
 #define elf_next_in_group(sec)	(elf_section_data(sec)->next_in_group)
 #define elf_fde_list(sec)	(elf_section_data(sec)->fde_list)
 #define elf_sec_group(sec)	(elf_section_data(sec)->sec_group)
+#define elf_section_eh_frame_entry(sec)	(elf_section_data(sec)->eh_frame_entry)
 
 #define xvec_get_elf_backend_data(xvec) \
   ((const struct elf_backend_data *) (xvec)->backend_data)
@@ -1983,8 +2018,15 @@ extern bfd_boolean _bfd_elf_strtab_emit
 extern void _bfd_elf_strtab_finalize
   (struct elf_strtab_hash *);
 
+extern bfd_boolean bfd_elf_parse_eh_frame_entries
+  (bfd *, struct bfd_link_info *);
+extern bfd_boolean _bfd_elf_parse_eh_frame_entry
+  (struct bfd_link_info *, asection *, struct elf_reloc_cookie *);
 extern void _bfd_elf_parse_eh_frame
   (bfd *, struct bfd_link_info *, asection *, struct elf_reloc_cookie *);
+extern bfd_boolean _bfd_elf_end_eh_frame_parsing
+  (struct bfd_link_info *info);
+
 extern bfd_boolean _bfd_elf_discard_section_eh_frame
   (bfd *, struct bfd_link_info *, asection *,
    bfd_boolean (*) (bfd_vma, void *), struct elf_reloc_cookie *);
@@ -1994,10 +2036,15 @@ extern bfd_vma _bfd_elf_eh_frame_section_offset
   (bfd *, struct bfd_link_info *, asection *, bfd_vma);
 extern bfd_boolean _bfd_elf_write_section_eh_frame
   (bfd *, struct bfd_link_info *, asection *, bfd_byte *);
+bfd_boolean _bfd_elf_write_section_eh_frame_entry
+  (bfd *, struct bfd_link_info *, asection *, bfd_byte *);
+extern bfd_boolean _bfd_elf_fixup_eh_frame_hdr (struct bfd_link_info *);
 extern bfd_boolean _bfd_elf_write_section_eh_frame_hdr
   (bfd *, struct bfd_link_info *);
 extern bfd_boolean _bfd_elf_eh_frame_present
   (struct bfd_link_info *);
+extern bfd_boolean _bfd_elf_eh_frame_entry_present
+  (struct bfd_link_info *);
 extern bfd_boolean _bfd_elf_maybe_strip_eh_frame_hdr
   (struct bfd_link_info *);
 
@@ -2021,6 +2068,8 @@ extern bfd_boolean _bfd_elf_create_dynamic_sections
   (bfd *, struct bfd_link_info *);
 extern bfd_boolean _bfd_elf_create_got_section
   (bfd *, struct bfd_link_info *);
+extern asection *_bfd_elf_section_for_symbol
+  (struct elf_reloc_cookie *, unsigned long, bfd_boolean);
 extern struct elf_link_hash_entry *_bfd_elf_define_linkage_sym
   (bfd *, struct bfd_link_info *, asection *, const char *);
 extern void _bfd_elf_init_1_index_section
diff --git a/bfd/elf-eh-frame.c b/bfd/elf-eh-frame.c
index faa0461..22068ab 100644
--- a/bfd/elf-eh-frame.c
+++ b/bfd/elf-eh-frame.c
@@ -452,6 +452,111 @@ make_pc_relative (unsigned char encoding, unsigned int ptr_size)
   return encoding | DW_EH_PE_pcrel;
 }
 
+/*  Examine each .eh_frame_entry section and discard those
+    those that are marked SEC_EXCLUDE.  */
+
+static void
+bfd_elf_discard_eh_frame_entry (struct eh_frame_hdr_info *hdr_info)
+{
+  unsigned int i;
+  for (i = 0; i < hdr_info->array_count; i++)
+    {
+      if (hdr_info->u.compact.entries[i]->flags & SEC_EXCLUDE)
+	{
+	  unsigned int j;
+	  for (j = i + 1; j < hdr_info->array_count; j++)
+	    hdr_info->u.compact.entries[j-1] = hdr_info->u.compact.entries[j];
+
+	  hdr_info->array_count--;
+	  hdr_info->u.compact.entries[hdr_info->array_count] = NULL;
+	  i--;
+        }
+    }
+}
+
+/* Add a .eh_frame_entry section.  */
+
+static void
+bfd_elf_record_eh_frame_entry (struct eh_frame_hdr_info *hdr_info,
+				 asection *sec)
+{
+  if (hdr_info->array_count == hdr_info->u.compact.allocated_entries)
+    {
+      if (hdr_info->u.compact.allocated_entries == 0)
+	{
+	  hdr_info->frame_hdr_is_compact = TRUE;
+	  hdr_info->u.compact.allocated_entries = 2;
+	  hdr_info->u.compact.entries =
+	    bfd_malloc (hdr_info->u.compact.allocated_entries
+			* sizeof (hdr_info->u.compact.entries[0]));
+	}
+      else
+	{
+	  hdr_info->u.compact.allocated_entries *= 2;
+	  hdr_info->u.compact.entries =
+	    bfd_realloc (hdr_info->u.compact.entries,
+			 hdr_info->u.compact.allocated_entries
+			   * sizeof (hdr_info->u.compact.entries[0]));
+	}
+
+      BFD_ASSERT (hdr_info->u.compact.entries);
+    }
+
+  hdr_info->u.compact.entries[hdr_info->array_count++] = sec;
+}
+
+/* Parse a .eh_frame_entry section.  Figure out which text section it
+   references.  */
+
+bfd_boolean
+_bfd_elf_parse_eh_frame_entry (struct bfd_link_info *info,
+			       asection *sec, struct elf_reloc_cookie *cookie)
+{
+  struct elf_link_hash_table *htab;
+  struct eh_frame_hdr_info *hdr_info;
+  unsigned long r_symndx;
+  asection *text_sec;
+
+  htab = elf_hash_table (info);
+  hdr_info = &htab->eh_info;
+
+  if (sec->size == 0
+      || sec->sec_info_type != SEC_INFO_TYPE_NONE)
+    {
+      return TRUE;
+    }
+
+  if (sec->output_section && bfd_is_abs_section (sec->output_section))
+    {
+      /* At least one of the sections is being discarded from the
+	 link, so we should just ignore them.  */
+      return TRUE;
+    }
+
+  if (cookie->rel == cookie->relend)
+    return FALSE;
+
+  /* The first relocation is the function start.  */
+  r_symndx = cookie->rel->r_info >> cookie->r_sym_shift;
+  if (r_symndx == STN_UNDEF)
+    return FALSE;
+
+  text_sec = _bfd_elf_section_for_symbol (cookie, r_symndx, FALSE);
+
+  if (text_sec == NULL)
+    return FALSE;
+
+  elf_section_eh_frame_entry (text_sec) = sec;
+  if (text_sec->output_section
+      && bfd_is_abs_section (text_sec->output_section))
+    sec->flags |= SEC_EXCLUDE;
+
+  sec->sec_info_type = SEC_INFO_TYPE_EH_FRAME_ENTRY;
+  elf_section_data (sec)->sec_info = text_sec;
+  bfd_elf_record_eh_frame_entry (hdr_info, sec);
+  return TRUE;
+}
+
 /* Try to parse .eh_frame section SEC, which belongs to ABFD.  Store the
    information in the section's sec_info field on success.  COOKIE
    describes the relocations in SEC.  */
@@ -925,7 +1030,7 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info,
   (*info->callbacks->einfo)
     (_("%P: error in %B(%A); no .eh_frame_hdr table will be created.\n"),
      abfd, sec);
-  hdr_info->table = FALSE;
+  hdr_info->u.dwarf.table = FALSE;
   if (sec_info)
     free (sec_info);
  success:
@@ -936,6 +1041,89 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info,
 #undef REQUIRE
 }
 
+/* Order eh_frame_hdr entries by the VMA of their text section.  */
+
+static int
+cmp_eh_frame_hdr (const void *a, const void *b)
+{
+  bfd_vma text_a;
+  bfd_vma text_b;
+  asection *sec;
+
+  sec = *(asection *const *)a;
+  sec = (asection *) elf_section_data (sec)->sec_info;
+  text_a = sec->output_section->vma + sec->output_offset;
+  sec = *(asection *const *)b;
+  sec = (asection *) elf_section_data (sec)->sec_info;
+  text_b = sec->output_section->vma + sec->output_offset;
+
+  if (text_a < text_b)
+    return -1;
+  return text_a > text_b;
+
+}
+
+/* Add space for a CANTUNWIND terminator to SEC if the text sections
+   referenced by it and NEXT are not contiguous, or NEXT is NULL.  */
+
+static void
+add_eh_frame_hdr_terminator (asection *sec,
+			     asection *next)
+{
+  bfd_vma end;
+  bfd_vma next_start;
+  asection *text_sec;
+
+  if (next)
+    {
+      /* See if there is a gap (presumably a text section without unwind info)
+	 between these two entries.  */
+      text_sec = (asection *) elf_section_data (sec)->sec_info;
+      end = text_sec->output_section->vma + text_sec->output_offset
+	    + text_sec->size;
+      text_sec = (asection *) elf_section_data (next)->sec_info;
+      next_start = text_sec->output_section->vma + text_sec->output_offset;
+      if (end == next_start)
+	return;
+    }
+
+  /* Add space for a CANTUNWIND terminator.  */
+  if (!sec->rawsize)
+    sec->rawsize = sec->size;
+
+  bfd_set_section_size (sec->owner, sec, sec->size + 8);
+}
+
+/* Finish a pass over all .eh_frame_entry sections.  */
+
+bfd_boolean
+_bfd_elf_end_eh_frame_parsing (struct bfd_link_info *info)
+{
+  struct eh_frame_hdr_info *hdr_info;
+  unsigned int i;
+
+  hdr_info = &elf_hash_table (info)->eh_info;
+
+  if (info->eh_frame_hdr_type != COMPACT_EH_HDR
+      || hdr_info->array_count == 0)
+    return FALSE;
+
+  bfd_elf_discard_eh_frame_entry (hdr_info);
+
+  qsort (hdr_info->u.compact.entries, hdr_info->array_count,
+	 sizeof (asection *), cmp_eh_frame_hdr);
+
+  for (i = 0; i < hdr_info->array_count - 1; i++)
+    {
+      add_eh_frame_hdr_terminator (hdr_info->u.compact.entries[i],
+				   hdr_info->u.compact.entries[i + 1]);
+    }
+
+  /* Add a CANTUNWIND terminator after the last entry.  */
+  add_eh_frame_hdr_terminator (hdr_info->u.compact.entries[i], NULL);
+  return TRUE;
+}
+
 /* Mark all relocations against CIE or FDE ENT, which occurs in
    .eh_frame section SEC.  COOKIE describes the relocations in SEC;
    its "rel" field can be changed freely.  */
@@ -1089,13 +1277,14 @@ find_merged_cie (bfd *abfd, struct bfd_link_info *info, asection *sec,
 
   /* See if we can merge this CIE with an earlier one.  */
   cie_compute_hash (cie);
-  if (hdr_info->cies == NULL)
+  if (hdr_info->u.dwarf.cies == NULL)
     {
-      hdr_info->cies = htab_try_create (1, cie_hash, cie_eq, free);
-      if (hdr_info->cies == NULL)
+      hdr_info->u.dwarf.cies = htab_try_create (1, cie_hash, cie_eq, free);
+      if (hdr_info->u.dwarf.cies == NULL)
 	return cie_inf;
     }
-  loc = htab_find_slot_with_hash (hdr_info->cies, cie, cie->hash, INSERT);
+  loc = htab_find_slot_with_hash (hdr_info->u.dwarf.cies, cie,
+				  cie->hash, INSERT);
   if (loc == NULL)
     return cie_inf;
 
@@ -1185,13 +1374,13 @@ _bfd_elf_discard_section_eh_frame
 		   which we cannot turn into PC relative,
 		   don't create the binary search table,
 		   since it is affected by runtime relocations.  */
-		hdr_info->table = FALSE;
+		hdr_info->u.dwarf.table = FALSE;
 		(*info->callbacks->einfo)
 		  (_("%P: FDE encoding in %B(%A) prevents .eh_frame_hdr"
 		     " table being created.\n"), abfd, sec);
 	      }
 	    ent->removed = 0;
-	    hdr_info->fde_count++;
+	    hdr_info->u.dwarf.fde_count++;
 	    ent->u.fde.cie_inf = find_merged_cie (abfd, info, sec, hdr_info,
 						  cookie, ent->u.fde.cie_inf);
 	  }
@@ -1230,19 +1419,28 @@ _bfd_elf_discard_section_eh_frame_hdr (bfd *abfd, struct bfd_link_info *info)
   htab = elf_hash_table (info);
   hdr_info = &htab->eh_info;
 
-  if (hdr_info->cies != NULL)
+  if (!hdr_info->frame_hdr_is_compact && hdr_info->u.dwarf.cies != NULL)
     {
-      htab_delete (hdr_info->cies);
-      hdr_info->cies = NULL;
+      htab_delete (hdr_info->u.dwarf.cies);
+      hdr_info->u.dwarf.cies = NULL;
     }
 
   sec = hdr_info->hdr_sec;
   if (sec == NULL)
     return FALSE;
 
-  sec->size = EH_FRAME_HDR_SIZE;
-  if (hdr_info->table)
-    sec->size += 4 + hdr_info->fde_count * 8;
+  if (info->eh_frame_hdr_type == COMPACT_EH_HDR)
+    {
+      /* For compact frames we only add the header.  The actual table comes
+         from the .eh_frame_entry sections.  */
+      sec->size = 8;
+    }
+  else
+    {
+      sec->size = EH_FRAME_HDR_SIZE;
+      if (hdr_info->u.dwarf.table)
+	sec->size += 4 + hdr_info->u.dwarf.fde_count * 8;
+    }
 
   elf_eh_frame_hdr (abfd) = sec;
   return TRUE;
@@ -1251,6 +1449,7 @@ _bfd_elf_discard_section_eh_frame_hdr (bfd *abfd, struct bfd_link_info *info)
 /* Return true if there is at least one non-empty .eh_frame section in
    input files.  Can only be called after ld has mapped input to
    output sections, and before sections are stripped.  */
+
 bfd_boolean
 _bfd_elf_eh_frame_present (struct bfd_link_info *info)
 {
@@ -1268,6 +1467,29 @@ _bfd_elf_eh_frame_present (struct bfd_link_info *info)
   return FALSE;
 }
 
+/* Return true if there is at least one .eh_frame_entry section in
+   input files.  */
+
+bfd_boolean
+_bfd_elf_eh_frame_entry_present (struct bfd_link_info *info)
+{
+  asection *o;
+  bfd *abfd;
+
+  for (abfd = info->input_bfds; abfd != NULL; abfd = abfd->link.next)
+    {
+      for (o = abfd->sections; o; o = o->next)
+	{
+	  const char *name = bfd_get_section_name (abfd, o);
+
+	  if (strcmp (name, ".eh_frame_entry")
+	      && !bfd_is_abs_section (o->output_section))
+	    return TRUE;
+	}
+    }
+  return FALSE;
+}
+
 /* This function is called from size_dynamic_sections.
    It needs to decide whether .eh_frame_hdr should be output or not,
    because when the dynamic symbol table has been sized it is too late
@@ -1278,6 +1500,8 @@ _bfd_elf_maybe_strip_eh_frame_hdr (struct bfd_link_info *info)
 {
   struct elf_link_hash_table *htab;
   struct eh_frame_hdr_info *hdr_info;
+  struct bfd_link_hash_entry *bh = NULL;
+  struct elf_link_hash_entry *h;
 
   htab = elf_hash_table (info);
   hdr_info = &htab->eh_info;
@@ -1285,15 +1509,32 @@ _bfd_elf_maybe_strip_eh_frame_hdr (struct bfd_link_info *info)
     return TRUE;
 
   if (bfd_is_abs_section (hdr_info->hdr_sec->output_section)
-      || !info->eh_frame_hdr
-      || !_bfd_elf_eh_frame_present (info))
+      || info->eh_frame_hdr_type == 0
+      || (info->eh_frame_hdr_type == DWARF2_EH_HDR
+	  && !_bfd_elf_eh_frame_present (info))
+      || (info->eh_frame_hdr_type == COMPACT_EH_HDR
+	  && !_bfd_elf_eh_frame_entry_present (info)))
     {
       hdr_info->hdr_sec->flags |= SEC_EXCLUDE;
       hdr_info->hdr_sec = NULL;
       return TRUE;
     }
 
-  hdr_info->table = TRUE;
+  /* Add a hidden symbol so that systems without access to PHDRs can
+     find the table.  */
+  if (! (_bfd_generic_link_add_one_symbol
+	 (info, info->output_bfd, "__GNU_EH_FRAME_HDR", BSF_LOCAL,
+	  hdr_info->hdr_sec, 0, NULL, FALSE, FALSE, &bh)))
+    return FALSE;
+
+  h = (struct elf_link_hash_entry *) bh;
+  h->def_regular = 1;
+  h->other = STV_HIDDEN;
+  get_elf_backend_data
+    (info->output_bfd)->elf_backend_hide_symbol (info, h, TRUE);
+
+  if (!hdr_info->frame_hdr_is_compact)
+    hdr_info->u.dwarf.table = TRUE;
   return TRUE;
 }
 
@@ -1384,6 +1625,83 @@ _bfd_elf_eh_frame_section_offset (bfd *output_bfd ATTRIBUTE_UNUSED,
 	  + extra_augmentation_data_bytes (sec_info->entry + mid));
 }
 
+/* Write out .eh_frame_entry section.  Add CANTUNWIND terminator if needed.
+   Also check that the contents look sane.  */
+
+bfd_boolean
+_bfd_elf_write_section_eh_frame_entry (bfd *abfd, struct bfd_link_info *info,
+				       asection *sec, bfd_byte *contents)
+{
+  const struct elf_backend_data *bed;
+  bfd_byte cantunwind[8];
+  bfd_vma addr;
+  bfd_vma last_addr;
+  bfd_vma offset;
+  asection *text_sec = (asection *) elf_section_data (sec)->sec_info;
+
+  if (!sec->rawsize)
+    sec->rawsize = sec->size;
+
+  BFD_ASSERT (sec->sec_info_type == SEC_INFO_TYPE_EH_FRAME_ENTRY);
+
+  /* Check to make sure that the text section corresponding to this eh_frame_entry
+     section has not been excluded.  In particular, mips16 stub entries will be
+     excluded outside of the normal process.  */
+  if (sec->flags & SEC_EXCLUDE
+      || text_sec->flags & SEC_EXCLUDE)
+    return TRUE;
+
+  if (!bfd_set_section_contents (abfd, sec->output_section, contents,
+				 sec->output_offset, sec->rawsize))
+      return FALSE;
+
+  last_addr = bfd_get_signed_32 (abfd, contents);
+  /* Check that all the entries are in order.  */
+  for (offset = 8; offset < sec->rawsize; offset += 8)
+    {
+      addr = bfd_get_signed_32 (abfd, contents + offset) + offset;
+      if (addr <= last_addr)
+	{
+	  (*_bfd_error_handler) (_("%B: %s not in order"), sec->owner, sec->name);
+	  return FALSE;
+	}
+
+      last_addr = addr;
+    }
+
+  addr = text_sec->output_section->vma + text_sec->output_offset
+	 + text_sec->size;
+  addr &= ~1;
+  addr -= (sec->output_section->vma + sec->output_offset + sec->rawsize);
+  if (addr & 1)
+    {
+      (*_bfd_error_handler) (_("%B: %s invalid input section size"),
+			     sec->owner, sec->name);
+      bfd_set_error (bfd_error_bad_value);
+      return FALSE;
+    }
+  if (last_addr >= addr + sec->rawsize)
+    {
+      (*_bfd_error_handler) (_("%B: %s points past end of text section"),
+			     sec->owner, sec->name);
+      bfd_set_error (bfd_error_bad_value);
+      return FALSE;
+    }
+
+  if (sec->size == sec->rawsize)
+    return TRUE;
+
+  bed = get_elf_backend_data (abfd);
+  BFD_ASSERT (sec->size == sec->rawsize + 8);
+  BFD_ASSERT ((addr & 1) == 0);
+  BFD_ASSERT (bed->cant_unwind_opcode);
+
+  bfd_put_32 (abfd, addr, cantunwind);
+  bfd_put_32 (abfd, (*bed->cant_unwind_opcode) (info), cantunwind + 4);
+  return bfd_set_section_contents (abfd, sec->output_section, cantunwind,
+				   sec->output_offset + sec->rawsize, 8);
+}
+
 /* Write out .eh_frame section.  This is called with the relocated
    contents.  */
 
@@ -1413,10 +1731,14 @@ _bfd_elf_write_section_eh_frame (bfd *abfd,
   htab = elf_hash_table (info);
   hdr_info = &htab->eh_info;
 
-  if (hdr_info->table && hdr_info->array == NULL)
-    hdr_info->array = (struct eh_frame_array_ent *)
-        bfd_malloc (hdr_info->fde_count * sizeof(*hdr_info->array));
-  if (hdr_info->array == NULL)
+  if (hdr_info->u.dwarf.table && hdr_info->u.dwarf.array == NULL)
+    {
+      hdr_info->frame_hdr_is_compact = FALSE;
+      hdr_info->u.dwarf.array = (struct eh_frame_array_ent *)
+        bfd_malloc (hdr_info->u.dwarf.fde_count
+		    * sizeof (*hdr_info->u.dwarf.array));
+    }
+  if (hdr_info->u.dwarf.array == NULL)
     hdr_info = NULL;
 
   /* The new offsets can be bigger or smaller than the original offsets.
@@ -1651,10 +1973,11 @@ _bfd_elf_write_section_eh_frame (bfd *abfd,
 		 dwarf_vma is 64-bit.  */
 	      if (sizeof (address) > 4 && ptr_size == 4)
 		address &= 0xffffffff;
-	      hdr_info->array[hdr_info->array_count].initial_loc = address;
-	      hdr_info->array[hdr_info->array_count].range
+	      hdr_info->u.dwarf.array[hdr_info->array_count].initial_loc
+		= address;
+	      hdr_info->u.dwarf.array[hdr_info->array_count].range
 		= read_value (abfd, buf + width, width, FALSE);
-	      hdr_info->array[hdr_info->array_count++].fde
+	      hdr_info->u.dwarf.array[hdr_info->array_count++].fde
 		= (sec->output_section->vma
 		   + sec->output_offset
 		   + ent->new_offset);
@@ -1756,10 +2079,111 @@ vma_compare (const void *a, const void *b)
   return 0;
 }
 
-/* Write out .eh_frame_hdr section.  This must be called after
-   _bfd_elf_write_section_eh_frame has been called on all input
-   .eh_frame sections.
-   .eh_frame_hdr format:
+/* Reorder .eh_frame_entry sections to match the associated text sections.
+   This routine is called during the final linking step, just before writing
+   the contents.  At this stage, sections in the eh_frame_hdr_info are already
+   sorted in order of increasing text section address and so we simply need
+   to make the .eh_frame_entrys follow that same order.  Note that it is
+   invalid for a linker script to try to force a particular order of
+   .eh_frame_entry sections.  */
+
+bfd_boolean
+_bfd_elf_fixup_eh_frame_hdr (struct bfd_link_info *info)
+{
+  asection *sec = NULL;
+  asection *osec;
+  struct eh_frame_hdr_info *hdr_info;
+  unsigned int i;
+  bfd_vma offset;
+  struct bfd_link_order *p;
+
+  hdr_info = &elf_hash_table (info)->eh_info;
+
+  if (hdr_info->hdr_sec == NULL
+      || info->eh_frame_hdr_type != COMPACT_EH_HDR
+      || hdr_info->array_count == 0)
+    return TRUE;
+
+  /* Change section output offsets to be in text section order.  */
+  offset = 8;
+  osec = hdr_info->u.compact.entries[0]->output_section;
+  for (i = 0; i < hdr_info->array_count; i++)
+    {
+      sec = hdr_info->u.compact.entries[i];
+      if (sec->output_section != osec)
+	{
+	  (*_bfd_error_handler)
+	    (_("Invalid output section for .eh_frame_entry: %s"),
+	     sec->output_section->name);
+	  return FALSE;
+	}
+      sec->output_offset = offset;
+      offset += sec->size;
+    }
+
+
+  /* Fix the link_order to match.  */
+  for (p = sec->output_section->map_head.link_order; p != NULL; p = p->next)
+    {
+      if (p->type != bfd_indirect_link_order)
+	abort();
+
+      p->offset = p->u.indirect.section->output_offset;
+      if (p->next != NULL)
+        i--;
+    }
+
+  if (i != 0)
+    {
+      (*_bfd_error_handler)
+	(_("Invalid contents in %s section"), osec->name);
+      return FALSE;
+    }
+
+  return TRUE;
+}
+
+/* The .eh_frame_hdr format for Compact EH frames:
+   ubyte version		(2)
+   ubyte eh_ref_enc		(DW_EH_PE_* encoding of typinfo references)
+   uint32_t count		(Number of entries in table)
+   [array from .eh_frame_entry sections]  */
+
+static bfd_boolean
+write_compact_eh_frame_hdr (bfd *abfd, struct bfd_link_info *info)
+{
+  struct elf_link_hash_table *htab;
+  struct eh_frame_hdr_info *hdr_info;
+  asection *sec;
+  const struct elf_backend_data *bed;
+  bfd_vma count;
+  bfd_byte contents[8];
+  unsigned int i;
+
+  htab = elf_hash_table (info);
+  hdr_info = &htab->eh_info;
+  sec = hdr_info->hdr_sec;
+
+  if (sec->size != 8)
+    abort();
+
+  for (i = 0; i < sizeof (contents); i++)
+    contents[i] = 0;
+
+  contents[0] = COMPACT_EH_HDR;
+  bed = get_elf_backend_data (abfd);
+
+  BFD_ASSERT (bed->compact_eh_encoding);
+  contents[1] = (*bed->compact_eh_encoding) (info);
+
+  count = (sec->output_section->size - 8) / 8;
+  bfd_put_32 (abfd, count, contents + 4);
+  return bfd_set_section_contents (abfd, sec->output_section, contents,
+				   (file_ptr) sec->output_offset, sec->size);
+}
+
+/* The .eh_frame_hdr format for DWARF frames:
+
    ubyte version		(currently 1)
    ubyte eh_frame_ptr_enc  	(DW_EH_PE_* encoding of pointer to start of
 				 .eh_frame section)
@@ -1778,8 +2202,8 @@ vma_compare (const void *a, const void *b)
 				 FDE initial_location field and FDE address,
 				 sorted by increasing initial_loc).  */
 
-bfd_boolean
-_bfd_elf_write_section_eh_frame_hdr (bfd *abfd, struct bfd_link_info *info)
+static bfd_boolean
+write_dwarf_eh_frame_hdr (bfd *abfd, struct bfd_link_info *info)
 {
   struct elf_link_hash_table *htab;
   struct eh_frame_hdr_info *hdr_info;
@@ -1789,100 +2213,130 @@ _bfd_elf_write_section_eh_frame_hdr (bfd *abfd, struct bfd_link_info *info)
   htab = elf_hash_table (info);
   hdr_info = &htab->eh_info;
   sec = hdr_info->hdr_sec;
+  bfd_byte *contents;
+  asection *eh_frame_sec;
+  bfd_size_type size;
+  bfd_vma encoded_eh_frame;
+
+  size = EH_FRAME_HDR_SIZE;
+  if (hdr_info->u.dwarf.array
+      && hdr_info->array_count == hdr_info->u.dwarf.fde_count)
+    size += 4 + hdr_info->u.dwarf.fde_count * 8;
+  contents = (bfd_byte *) bfd_malloc (size);
+  if (contents == NULL)
+    return FALSE;
 
-  if (info->eh_frame_hdr && sec != NULL)
+  eh_frame_sec = bfd_get_section_by_name (abfd, ".eh_frame");
+  if (eh_frame_sec == NULL)
     {
-      bfd_byte *contents;
-      asection *eh_frame_sec;
-      bfd_size_type size;
-      bfd_vma encoded_eh_frame;
-
-      size = EH_FRAME_HDR_SIZE;
-      if (hdr_info->array && hdr_info->array_count == hdr_info->fde_count)
-	size += 4 + hdr_info->fde_count * 8;
-      contents = (bfd_byte *) bfd_malloc (size);
-      if (contents == NULL)
-	return FALSE;
+      free (contents);
+      return FALSE;
+    }
 
-      eh_frame_sec = bfd_get_section_by_name (abfd, ".eh_frame");
-      if (eh_frame_sec == NULL)
-	{
-	  free (contents);
-	  return FALSE;
-	}
+  memset (contents, 0, EH_FRAME_HDR_SIZE);
+  /* Version.  */
+  contents[0] = 1;
+  /* .eh_frame offset.  */
+  contents[1] = get_elf_backend_data (abfd)->elf_backend_encode_eh_address
+    (abfd, info, eh_frame_sec, 0, sec, 4, &encoded_eh_frame);
 
-      memset (contents, 0, EH_FRAME_HDR_SIZE);
-      /* Version.  */
-      contents[0] = 1;
-      /* .eh_frame offset.  */
-      contents[1] = get_elf_backend_data (abfd)->elf_backend_encode_eh_address
-	(abfd, info, eh_frame_sec, 0, sec, 4, &encoded_eh_frame);
+  if (hdr_info->u.dwarf.array
+      && hdr_info->array_count == hdr_info->u.dwarf.fde_count)
+    {
+      /* FDE count encoding.  */
+      contents[2] = DW_EH_PE_udata4;
+      /* Search table encoding.  */
+      contents[3] = DW_EH_PE_datarel | DW_EH_PE_sdata4;
+    }
+  else
+    {
+      contents[2] = DW_EH_PE_omit;
+      contents[3] = DW_EH_PE_omit;
+    }
+  bfd_put_32 (abfd, encoded_eh_frame, contents + 4);
 
-      if (hdr_info->array && hdr_info->array_count == hdr_info->fde_count)
+  if (contents[2] != DW_EH_PE_omit)
+    {
+      unsigned int i;
+      bfd_boolean overlap, overflow;
+
+      bfd_put_32 (abfd, hdr_info->u.dwarf.fde_count,
+		  contents + EH_FRAME_HDR_SIZE);
+      qsort (hdr_info->u.dwarf.array, hdr_info->u.dwarf.fde_count,
+	     sizeof (*hdr_info->u.dwarf.array), vma_compare);
+      overlap = FALSE;
+      overflow = FALSE;
+      for (i = 0; i < hdr_info->u.dwarf.fde_count; i++)
 	{
-	  /* FDE count encoding.  */
-	  contents[2] = DW_EH_PE_udata4;
-	  /* Search table encoding.  */
-	  contents[3] = DW_EH_PE_datarel | DW_EH_PE_sdata4;
+	  bfd_vma val;
+
+	  val = hdr_info->u.dwarf.array[i].initial_loc
+	    - sec->output_section->vma;
+	  val = ((val & 0xffffffff) ^ 0x80000000) - 0x80000000;
+	  if (elf_elfheader (abfd)->e_ident[EI_CLASS] == ELFCLASS64
+	      && (hdr_info->u.dwarf.array[i].initial_loc
+		  != sec->output_section->vma + val))
+	    overflow = TRUE;
+	  bfd_put_32 (abfd, val, contents + EH_FRAME_HDR_SIZE + i * 8 + 4);
+	  val = hdr_info->u.dwarf.array[i].fde - sec->output_section->vma;
+	  val = ((val & 0xffffffff) ^ 0x80000000) - 0x80000000;
+	  if (elf_elfheader (abfd)->e_ident[EI_CLASS] == ELFCLASS64
+	      && (hdr_info->u.dwarf.array[i].fde
+		  != sec->output_section->vma + val))
+	    overflow = TRUE;
+	  bfd_put_32 (abfd, val, contents + EH_FRAME_HDR_SIZE + i * 8 + 8);
+	  if (i != 0
+	      && (hdr_info->u.dwarf.array[i].initial_loc
+		  < (hdr_info->u.dwarf.array[i - 1].initial_loc
+		     + hdr_info->u.dwarf.array[i - 1].range)))
+	    overlap = TRUE;
 	}
-      else
+      if (overflow)
+	(*info->callbacks->einfo) (_("%P: .eh_frame_hdr entry overflow.\n"));
+      if (overlap)
+	(*info->callbacks->einfo)
+	  (_("%P: .eh_frame_hdr refers to overlapping FDEs.\n"));
+      if (overflow || overlap)
 	{
-	  contents[2] = DW_EH_PE_omit;
-	  contents[3] = DW_EH_PE_omit;
+	  bfd_set_error (bfd_error_bad_value);
+	  retval = FALSE;
 	}
-      bfd_put_32 (abfd, encoded_eh_frame, contents + 4);
+    }
 
-      if (contents[2] != DW_EH_PE_omit)
-	{
-	  unsigned int i;
+  /* FIXME: octets_per_byte.  */
+  if (!bfd_set_section_contents (abfd, sec->output_section, contents,
+				 (file_ptr) sec->output_offset,
+				 sec->size))
+    retval = FALSE;
+  free (contents);
+
+  if (hdr_info->u.dwarf.array != NULL)
+    free (hdr_info->u.dwarf.array);
+  return retval;
+}
 
-	  bfd_put_32 (abfd, hdr_info->fde_count, contents + EH_FRAME_HDR_SIZE);
-	  qsort (hdr_info->array, hdr_info->fde_count,
-		 sizeof (*hdr_info->array), vma_compare);
-	  for (i = 0; i < hdr_info->fde_count; i++)
-	    {
-	      bfd_vma val;
+/* Write out .eh_frame_hdr section.  This must be called after
+   _bfd_elf_write_section_eh_frame has been called on all input
+   .eh_frame sections.  */
 
-	      val = hdr_info->array[i].initial_loc - sec->output_section->vma;
-	      val = ((val & 0xffffffff) ^ 0x80000000) - 0x80000000;
-	      if (elf_elfheader (abfd)->e_ident[EI_CLASS] == ELFCLASS64
-		  && (hdr_info->array[i].initial_loc
-		      != sec->output_section->vma + val))
-		(*info->callbacks->einfo)
-		  (_("%X%P: .eh_frame_hdr table[%u] PC overflow.\n"), i);
-	      bfd_put_32 (abfd, val, contents + EH_FRAME_HDR_SIZE + i * 8 + 4);
-
-	      val = hdr_info->array[i].fde - sec->output_section->vma;
-	      val = ((val & 0xffffffff) ^ 0x80000000) - 0x80000000;
-	      if (elf_elfheader (abfd)->e_ident[EI_CLASS] == ELFCLASS64
-		  && (hdr_info->array[i].fde
-		      != sec->output_section->vma + val))
-		(*info->callbacks->einfo)
-		  (_("%X%P: .eh_frame_hdr table[%u] FDE overflow.\n"), i);
-	      bfd_put_32 (abfd, val, contents + EH_FRAME_HDR_SIZE + i * 8 + 8);
+bfd_boolean
+_bfd_elf_write_section_eh_frame_hdr (bfd *abfd, struct bfd_link_info *info)
+{
+  struct elf_link_hash_table *htab;
+  struct eh_frame_hdr_info *hdr_info;
+  asection *sec;
 
-	      if (i != 0
-		  && (hdr_info->array[i].initial_loc
-		      < (hdr_info->array[i - 1].initial_loc
-			 + hdr_info->array[i - 1].range)))
-		(*info->callbacks->einfo)
-		  (_("%X%P: .eh_frame_hdr table[%u] FDE at %V overlaps "
-		     "table[%u] FDE at %V.\n"),
-		   i - 1, hdr_info->array[i - 1].fde,
-		   i, hdr_info->array[i].fde);
-	    }
-	}
+  htab = elf_hash_table (info);
+  hdr_info = &htab->eh_info;
+  sec = hdr_info->hdr_sec;
 
-      /* FIXME: octets_per_byte.  */
-      if (!bfd_set_section_contents (abfd, sec->output_section, contents,
-				     (file_ptr) sec->output_offset,
-				     sec->size))
-	retval = FALSE;
-      free (contents);
-    }
-  if (hdr_info->array != NULL)
-    free (hdr_info->array);
-  return retval;
+  if (info->eh_frame_hdr_type == 0 || sec == NULL)
+    return TRUE;
+
+  if (info->eh_frame_hdr_type == COMPACT_EH_HDR)
+    return write_compact_eh_frame_hdr (abfd, info);
+  else
+    return write_dwarf_eh_frame_hdr (abfd, info);
 }
 
 /* Return the width of FDE addresses.  This is the default implementation.  */
diff --git a/bfd/elflink.c b/bfd/elflink.c
index 6efe1e4..9520906 100644
--- a/bfd/elflink.c
+++ b/bfd/elflink.c
@@ -54,6 +54,47 @@ struct elf_find_verdep_info
 static bfd_boolean _bfd_elf_fix_symbol_flags
   (struct elf_link_hash_entry *, struct elf_info_failed *);
 
+asection *
+_bfd_elf_section_for_symbol (struct elf_reloc_cookie *cookie,
+			     unsigned long r_symndx,
+			     bfd_boolean discard)
+{
+  if (r_symndx >= cookie->locsymcount
+      || ELF_ST_BIND (cookie->locsyms[r_symndx].st_info) != STB_LOCAL)
+    {
+      struct elf_link_hash_entry *h;
+
+      h = cookie->sym_hashes[r_symndx - cookie->extsymoff];
+
+      while (h->root.type == bfd_link_hash_indirect
+	     || h->root.type == bfd_link_hash_warning)
+	h = (struct elf_link_hash_entry *) h->root.u.i.link;
+
+      if ((h->root.type == bfd_link_hash_defined
+	   || h->root.type == bfd_link_hash_defweak)
+	   && discarded_section (h->root.u.def.section))
+        return h->root.u.def.section;
+      else
+	return NULL;
+    }
+  else
+    {
+      /* It's not a relocation against a global symbol,
+	 but it could be a relocation against a local
+	 symbol for a discarded section.  */
+      asection *isec;
+      Elf_Internal_Sym *isym;
+
+      /* Need to: get the symbol; get the section.  */
+      isym = &cookie->locsyms[r_symndx];
+      isec = bfd_section_from_elf_index (cookie->abfd, isym->st_shndx);
+      if (isec != NULL
+	  && discard ? discarded_section (isec) : 1)
+	return isec;
+     }
+  return NULL;
+}
+
 /* Define a symbol in a dynamic linkage section.  */
 
 struct elf_link_hash_entry *
@@ -9284,6 +9325,7 @@ elf_section_ignore_discarded_relocs (asection *sec)
     {
     case SEC_INFO_TYPE_STABS:
     case SEC_INFO_TYPE_EH_FRAME:
+    case SEC_INFO_TYPE_EH_FRAME_ENTRY:
       return TRUE;
     default:
       break;
@@ -10215,6 +10257,14 @@ elf_link_input_bfd (struct elf_final_link_info *flinfo, bfd *input_bfd)
 	      return FALSE;
 	  }
 	  break;
+	case SEC_INFO_TYPE_EH_FRAME_ENTRY:
+	  {
+	    if (! _bfd_elf_write_section_eh_frame_entry (output_bfd,
+							 flinfo->info,
+							 o, contents))
+	      return FALSE;
+	  }
+	  break;
 	default:
 	  {
 	    /* FIXME: octets_per_byte.  */
@@ -11085,6 +11135,9 @@ bfd_elf_final_link (bfd *abfd, struct bfd_link_info *info)
 	return FALSE;
     }
 
+  if (!_bfd_elf_fixup_eh_frame_hdr (info))
+    return FALSE;
+
   /* Since ELF permits relocations to be against local symbols, we
      must have the local symbols available when we do the relocations.
      Since we would rather only read the local symbols once, and we
@@ -11994,6 +12047,11 @@ _bfd_elf_gc_mark (struct bfd_link_info *info,
 	}
     }
 
+  eh_frame = elf_section_eh_frame_entry (sec);
+  if (ret && eh_frame && !eh_frame->gc_mark)
+    if (!_bfd_elf_gc_mark (info, eh_frame, gc_mark_hook))
+      ret = FALSE;
+
   return ret;
 }
 
@@ -12409,6 +12467,36 @@ _bfd_elf_gc_keep (struct bfd_link_info *info)
     }
 }
 
+bfd_boolean
+bfd_elf_parse_eh_frame_entries (bfd *abfd ATTRIBUTE_UNUSED,
+				struct bfd_link_info *info)
+{
+  bfd *ibfd = info->input_bfds;
+
+  for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link.next)
+    {
+      asection *sec;
+      struct elf_reloc_cookie cookie;
+
+      if (bfd_get_flavour (ibfd) != bfd_target_elf_flavour)
+	continue;
+
+      if (!init_reloc_cookie (&cookie, info, ibfd))
+	return FALSE;
+
+      for (sec = ibfd->sections; sec; sec = sec->next)
+	{
+	  if (CONST_STRNEQ (bfd_section_name (ibfd, sec), ".eh_frame_entry")
+	      && init_reloc_cookie_rels (&cookie, info, ibfd, sec))
+	    {
+	      _bfd_elf_parse_eh_frame_entry (info, sec, &cookie);
+	      fini_reloc_cookie_rels (&cookie, sec);
+	    }
+	}
+    }
+  return TRUE;
+}
+
 /* Do mark and sweep of unused sections.  */
 
 bfd_boolean
@@ -12432,7 +12520,9 @@ bfd_elf_gc_sections (bfd *abfd, struct bfd_link_info *info)
 
   /* Try to parse each bfd's .eh_frame section.  Point elf_eh_frame_section
      at the .eh_frame section if we can mark the FDEs individually.  */
-  for (sub = info->input_bfds; sub != NULL; sub = sub->link.next)
+  for (sub = info->input_bfds;
+       info->eh_frame_hdr_type != COMPACT_EH_HDR && sub != NULL;
+       sub = sub->link.next)
     {
       asection *sec;
       struct elf_reloc_cookie cookie;
@@ -12936,7 +13026,9 @@ bfd_elf_discard_info (bfd *output_bfd, struct bfd_link_info *info)
 	}
     }
 
-  o = bfd_get_section_by_name (output_bfd, ".eh_frame");
+  o = NULL;
+  if (info->eh_frame_hdr_type != COMPACT_EH_HDR)
+    o = bfd_get_section_by_name (output_bfd, ".eh_frame");
   if (o != NULL)
     {
       asection *i;
@@ -12984,7 +13076,10 @@ bfd_elf_discard_info (bfd *output_bfd, struct bfd_link_info *info)
 	}
     }
 
-  if (info->eh_frame_hdr
+  if (info->eh_frame_hdr_type == COMPACT_EH_HDR)
+    _bfd_elf_end_eh_frame_parsing (info);
+
+  if (info->eh_frame_hdr_type
       && !info->relocatable
       && _bfd_elf_discard_section_eh_frame_hdr (output_bfd, info))
     changed = 1;
diff --git a/bfd/elfxx-mips.c b/bfd/elfxx-mips.c
index 50ee9ad..a5e6453 100644
--- a/bfd/elfxx-mips.c
+++ b/bfd/elfxx-mips.c
@@ -36,6 +36,7 @@
 #include "elfxx-mips.h"
 #include "elf/mips.h"
 #include "elf-vxworks.h"
+#include "dwarf2.h"
 
 /* Get the ECOFF swapping routines.  */
 #include "coff/sym.h"
@@ -16109,3 +16110,17 @@ _bfd_mips_post_process_headers (bfd *abfd, struct bfd_link_info *link_info)
       || mips_elf_tdata (abfd)->abiflags.fp_abi == Val_GNU_MIPS_ABI_FP_64A)
     i_ehdrp->e_ident[EI_ABIVERSION] = 3;
 }
+
+int
+_bfd_mips_elf_compact_eh_encoding (struct bfd_link_info *link_info ATTRIBUTE_UNUSED)
+{
+  return DW_EH_PE_pcrel | DW_EH_PE_sdata4;
+}
+
+/* Return the opcode for can't unwind.  */
+
+int
+_bfd_mips_elf_cant_unwind_opcode (struct bfd_link_info *link_info ATTRIBUTE_UNUSED)
+{
+  return COMPACT_EH_CANT_UNWIND_OPCODE;
+}
diff --git a/bfd/elfxx-mips.h b/bfd/elfxx-mips.h
index 8151d3b..03ff4fb 100644
--- a/bfd/elfxx-mips.h
+++ b/bfd/elfxx-mips.h
@@ -168,6 +168,9 @@ extern const struct bfd_elf_special_section _bfd_mips_elf_special_sections [];
 
 extern bfd_boolean _bfd_mips_elf_common_definition (Elf_Internal_Sym *);
 
+extern int _bfd_mips_elf_compact_eh_encoding (struct bfd_link_info *);
+extern int _bfd_mips_elf_cant_unwind_opcode (struct bfd_link_info *);
+
 static inline bfd_boolean
 gprel16_reloc_p (unsigned int r_type)
 {
@@ -191,3 +194,5 @@ literal_reloc_p (int r_type)
 #define elf_backend_merge_symbol_attribute  _bfd_mips_elf_merge_symbol_attribute
 #define elf_backend_ignore_undef_symbol _bfd_mips_elf_ignore_undef_symbol
 #define elf_backend_post_process_headers _bfd_mips_post_process_headers
+#define elf_backend_compact_eh_encoding _bfd_mips_elf_compact_eh_encoding
+#define elf_backend_cant_unwind_opcode _bfd_mips_elf_cant_unwind_opcode
diff --git a/bfd/elfxx-target.h b/bfd/elfxx-target.h
index 0085d6c..0acecaf 100644
--- a/bfd/elfxx-target.h
+++ b/bfd/elfxx-target.h
@@ -676,6 +676,14 @@
 #define elf_backend_get_reloc_section _bfd_elf_get_reloc_section
 #endif
 
+#ifndef elf_backend_compact_eh_encoding
+#define elf_backend_compact_eh_encoding NULL
+#endif
+
+#ifndef elf_backend_cant_unwind_opcode
+#define elf_backend_cant_unwind_opcode 0
+#endif
+
 #ifndef elf_match_priority
 #define elf_match_priority \
   (ELF_ARCH == bfd_arch_unknown ? 2 : ELF_OSABI == ELFOSABI_NONE ? 1 : 0)
@@ -788,6 +796,8 @@ static struct elf_backend_data elfNN_bed =
   elf_backend_obj_attrs_section_type,
   elf_backend_obj_attrs_order,
   elf_backend_obj_attrs_handle_unknown,
+  elf_backend_compact_eh_encoding,
+  elf_backend_cant_unwind_opcode,
   elf_backend_static_tls_alignment,
   elf_backend_stack_align,
   elf_backend_collect,
diff --git a/bfd/section.c b/bfd/section.c
index 24422bf..6af174a 100644
--- a/bfd/section.c
+++ b/bfd/section.c
@@ -397,6 +397,7 @@ CODE_FRAGMENT
 .#define SEC_INFO_TYPE_EH_FRAME  3
 .#define SEC_INFO_TYPE_JUST_SYMS 4
 .#define SEC_INFO_TYPE_TARGET    5
+.#define SEC_INFO_TYPE_EH_FRAME_ENTRY 6
 .
 .  {* Nonzero if this section uses RELA relocations, rather than REL.  *}
 .  unsigned int use_rela_p:1;