From 151411f8af16723a12e0e0eedc1ecdbea648c1b0 Mon Sep 17 00:00:00 2001 From: "H.J. Lu" Date: Wed, 8 Apr 2015 07:53:54 -0700 Subject: 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. --- gas/write.c | 43 ++++++++++++++++++++++++++++++------------- 1 file changed, 30 insertions(+), 13 deletions(-) (limited to 'gas/write.c') diff --git a/gas/write.c b/gas/write.c index 1ae47a9..bc76962 100644 --- a/gas/write.c +++ b/gas/write.c @@ -1413,6 +1413,9 @@ compress_debug (bfd *abfd, asection *sec, void *xxx ATTRIBUTE_UNUSED) struct z_stream_s *strm; int x; flagword flags = bfd_get_section_flags (abfd, sec); + unsigned int header_size, compression_header_size; + /* Maximimum compression header is 24 bytes. */ + bfd_byte compression_header[24]; if (seginfo == NULL || sec->size < 32 @@ -1427,18 +1430,26 @@ compress_debug (bfd *abfd, asection *sec, void *xxx ATTRIBUTE_UNUSED) if (strm == NULL) return; + if (flag_compress_debug == COMPRESS_DEBUG_GABI_ZLIB) + stdoutput->flags |= BFD_COMPRESS | BFD_COMPRESS_GABI; + else + stdoutput->flags |= BFD_COMPRESS; + compression_header_size + = bfd_get_compression_header_size (stdoutput, NULL); + /* Create a new frag to contain the "ZLIB" header. */ + header_size = 12 + compression_header_size; first_newf = frag_alloc (ob); - if (obstack_room (ob) < 12) + if (obstack_room (ob) < header_size) first_newf = frag_alloc (ob); - if (obstack_room (ob) < 12) - as_fatal (_("can't extend frag %u chars"), 12); + if (obstack_room (ob) < header_size) + as_fatal (_("can't extend frag %u chars"), header_size); last_newf = first_newf; - obstack_blank_fast (ob, 12); + obstack_blank_fast (ob, header_size); last_newf->fr_type = rs_fill; - last_newf->fr_fix = 12; + last_newf->fr_fix = header_size; header = last_newf->fr_literal; - compressed_size = 12; + compressed_size = header_size; /* Stream the frags through the compression engine, adding new frags as necessary to accomodate the compressed output. */ @@ -1522,21 +1533,27 @@ compress_debug (bfd *abfd, asection *sec, void *xxx ATTRIBUTE_UNUSED) if (compressed_size >= uncompressed_size) return; - memcpy (header, "ZLIB", 4); - bfd_putb64 (uncompressed_size, header + 4); + if (compression_header_size) + memcpy (header, compression_header, compression_header_size); + memcpy (header + compression_header_size, "ZLIB", 4); + bfd_putb64 (uncompressed_size, header + compression_header_size + 4); /* Replace the uncompressed frag list with the compressed frag list. */ seginfo->frchainP->frch_root = first_newf; seginfo->frchainP->frch_last = last_newf; /* Update the section size and its name. */ + bfd_update_compression_header (abfd, (bfd_byte *) header, sec); x = bfd_set_section_size (abfd, sec, compressed_size); gas_assert (x); - compressed_name = (char *) xmalloc (strlen (section_name) + 2); - compressed_name[0] = '.'; - compressed_name[1] = 'z'; - strcpy (compressed_name + 2, section_name + 1); - bfd_section_name (stdoutput, sec) = compressed_name; + if (!compression_header_size) + { + compressed_name = (char *) xmalloc (strlen (section_name) + 2); + compressed_name[0] = '.'; + compressed_name[1] = 'z'; + strcpy (compressed_name + 2, section_name + 1); + bfd_section_name (stdoutput, sec) = compressed_name; + } } static void -- cgit v1.1