Add SHF_COMPRESSED support to gas and objcopy

This patch adds --compress-debug-sections={none|zlib|zlib-gnu|zlib-gabi}
options to gas and objcopy for ELF files. They control how DWARF debug
sections are compressed.  --compress-debug-sections=none is equivalent to
--nocompress-debug-sections.  --compress-debug-sections=zlib and
--compress-debug-sections=zlib-gnu are equivalent to
--compress-debug-sections.  --compress-debug-sections=zlib-gabi compresses
DWARF debug sections with SHF_COMPRESSED from the ELF ABI.  No linker
changes are required to support SHF_COMPRESSED.

bfd/

	* archive.c (_bfd_get_elt_at_filepos): Also copy BFD_COMPRESS_GABI
	bit.
	* bfd.c (bfd::flags): Increase size to 18 bits.
	(BFD_COMPRESS_GABI): New.
	(BFD_FLAGS_SAVED): Add BFD_COMPRESS_GABI.
	(BFD_FLAGS_FOR_BFD_USE_MASK): Likewise.
	(bfd_update_compression_header): New fuction.
	(bfd_check_compression_header): Likewise.
	(bfd_get_compression_header_size): Likewise.
	(bfd_is_section_compressed_with_header): Likewise.
	* compress.c (MAX_COMPRESSION_HEADER_SIZE): New.
	(bfd_compress_section_contents): Return the uncompressed size if
	the full section contents is compressed successfully.  Support
	converting from/to .zdebug* sections.
	(bfd_get_full_section_contents): Call
	bfd_get_compression_header_size to get compression header size.
	(bfd_is_section_compressed): Renamed to ...
	(bfd_is_section_compressed_with_header): This.  Add a pointer
	argument to return compression header size.
	(bfd_is_section_compressed): Use it.
	(bfd_init_section_decompress_status): Call
	bfd_get_compression_header_size to get compression header size.
	Return FALSE if uncompressed section size is 0.
	* elf.c (_bfd_elf_make_section_from_shdr): Support converting
	from/to .zdebug* sections.
	* bfd-in2.h: Regenerated.

binutils/

	* objcopy.c (do_debug_sections): Add compress_zlib,
	compress_gnu_zlib and compress_gabi_zlib.
	(copy_options): Use optional_argument on compress-debug-sections.
	(copy_usage): Update --compress-debug-sections.
	(copy_file): Handle compress_zlib, compress_gnu_zlib and
	compress_gabi_zlib.
	(copy_main): Handle
	--compress-debug-sections={none|zlib|zlib-gnu|zlib-gabi}.
	* doc/binutils.texi: Document
	--compress-debug-sections={none|zlib|zlib-gnu|zlib-gabi}.

binutils/testsuite/

	* compress.exp: Add tests for
	--compress-debug-sections={none|zlib|zlib-gnu|zlib-gabi}.
	* binutils-all/dw2-3.rS: New file.
	* binutils-all/dw2-3.rt: Likewise.
	* binutils-all/libdw2-compressedgabi.out: Likewise.

gas/

	* as.c (show_usage): Update --compress-debug-sections.
	(std_longopts): Use optional_argument on compress-debug-sections.
	(parse_args): Handle
	--compress-debug-sections={none|zlib|zlib-gnu|zlib-gabi}.
	* as.h (compressed_debug_section_type): New.
	(flag_compress_debug): Change type to compressed_debug_section_type.
	--compress-debug-sections={none|zlib|zlib-gnu|zlib-gabi}.
	* write.c (compress_debug): Set BFD_COMPRESS_GABI for
	--compress-debug-sections=zlib-gabi.  Call
	bfd_get_compression_header_size to get compression header size.
	Don't rename section name for --compress-debug-sections=zlib-gabi.
	* config/tc-i386.c (compressed_debug_section_type): Set to
	COMPRESS_DEBUG_ZLIB.
	* doc/as.texinfo: Document
	--compress-debug-sections={none|zlib|zlib-gnu|zlib-gabi}.

gas/testsuite/

	* gas/i386/dw2-compressed-1.d: New file.
	* gas/i386/dw2-compressed-2.d: Likewise.
	* gas/i386/dw2-compressed-3.d: Likewise.
	* gas/i386/x86-64-dw2-compressed-2.d: Likewise.
	* gas/i386/i386.exp: Run dw2-compressed-2, dw2-compressed-1,
	dw2-compressed-3 and x86-64-dw2-compressed-2.

ld/testsuite/

	* ld-elf/compress.exp: Add a test for
	--compress-debug-sections=zlib-gabi.
	(build_tests): Add 2 tests for --compress-debug-sections=zlib-gabi.
	(run_tests): Likewise.
	Verify linker output with zlib-gabi compressed debug input.
	* ld-elf/compressed1a.d: New file.
	* ld-elf/compressed1b.d: Likewise.
	* ld-elf/compressed1c.d: Likewise.

1 files changed, 24 insertions, 4 deletions

diff --git a/gas/as.c b/gas/as.c
index a670d3e..2a8923f 100644
--- a/gas/as.c
+++ b/gas/as.c
@@ -246,7 +246,7 @@ Options:\n\
   fprintf (stream, _("\
   --alternate             initially turn on alternate macro syntax\n"));
   fprintf (stream, _("\
-  --compress-debug-sections\n\
+  --compress-debug-sections[={none|zlib|zlib-gnu|zlib-gabi}]\n\
                           compress DWARF debug sections using zlib\n"));
   fprintf (stream, _("\
   --nocompress-debug-sections\n\
@@ -471,7 +471,7 @@ parse_args (int * pargc, char *** pargv)
     ,{"a", optional_argument, NULL, 'a'}
     /* Handle -al=<FILE>.  */
     ,{"al", optional_argument, NULL, OPTION_AL}
-    ,{"compress-debug-sections", no_argument, NULL, OPTION_COMPRESS_DEBUG}
+    ,{"compress-debug-sections", optional_argument, NULL, OPTION_COMPRESS_DEBUG}
     ,{"nocompress-debug-sections", no_argument, NULL, OPTION_NOCOMPRESS_DEBUG}
     ,{"debug-prefix-map", required_argument, NULL, OPTION_DEBUG_PREFIX_MAP}
     ,{"defsym", required_argument, NULL, OPTION_DEFSYM}
@@ -655,11 +655,31 @@ This program has absolutely no warranty.\n"));
 	  exit (EXIT_SUCCESS);
 
 	case OPTION_COMPRESS_DEBUG:
-	  flag_compress_debug = 1;
+	  if (optarg)
+	    {
+#if defined OBJ_ELF || defined OBJ_MAYBE_ELF
+	      if (strcasecmp (optarg, "none") == 0)
+		flag_compress_debug = COMPRESS_DEBUG_NONE;
+	      else if (strcasecmp (optarg, "zlib") == 0)
+		flag_compress_debug = COMPRESS_DEBUG_ZLIB;
+	      else if (strcasecmp (optarg, "zlib-gnu") == 0)
+		flag_compress_debug = COMPRESS_DEBUG_GNU_ZLIB;
+	      else if (strcasecmp (optarg, "zlib-gabi") == 0)
+		flag_compress_debug = COMPRESS_DEBUG_GABI_ZLIB;
+	      else
+		as_fatal (_("Invalid --compress-debug-sections option: `%s'"),
+			  optarg);
+#else
+	      as_fatal (_("--compress-debug-sections=%s is unsupported"),
+			optarg);
+#endif
+	    }
+	  else
+	    flag_compress_debug = COMPRESS_DEBUG;
 	  break;
 
 	case OPTION_NOCOMPRESS_DEBUG:
-	  flag_compress_debug = 0;
+	  flag_compress_debug = COMPRESS_DEBUG_NONE;
 	  break;
 
 	case OPTION_DEBUG_PREFIX_MAP: