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. --- bfd/elf.c | 75 +++++++++++++++++++++++++++++++++++++++------------------------ 1 file changed, 46 insertions(+), 29 deletions(-) (limited to 'bfd/elf.c') diff --git a/bfd/elf.c b/bfd/elf.c index 5fad4f1..a031b9e 100644 --- a/bfd/elf.c +++ b/bfd/elf.c @@ -1042,26 +1042,35 @@ _bfd_elf_make_section_from_shdr (bfd *abfd, { enum { nothing, compress, decompress } action = nothing; char *new_name; + int compression_header_size; + bfd_boolean compressed + = bfd_is_section_compressed_with_header (abfd, newsect, + &compression_header_size); - if (bfd_is_section_compressed (abfd, newsect)) + if (compressed) { /* Compressed section. Check if we should decompress. */ if ((abfd->flags & BFD_DECOMPRESS)) action = decompress; } - else + + /* Compress the uncompressed section or convert from/to .zdebug* + section. Check if we should compress. */ + if (action == nothing) { - /* Normal section. Check if we should compress. */ - if ((abfd->flags & BFD_COMPRESS) && newsect->size != 0) + if (newsect->size != 0 + && (abfd->flags & BFD_COMPRESS) + && compression_header_size >= 0 + && (!compressed + || ((compression_header_size > 0) + != ((abfd->flags & BFD_COMPRESS_GABI) != 0)))) action = compress; + else + return TRUE; } - new_name = NULL; - switch (action) + if (action == compress) { - case nothing: - break; - case compress: if (!bfd_init_section_compress_status (abfd, newsect)) { (*_bfd_error_handler) @@ -1069,25 +1078,9 @@ _bfd_elf_make_section_from_shdr (bfd *abfd, abfd, name); return FALSE; } - /* PR binutils/18087: Compression does not always make a section - smaller. So only rename the section when compression has - actually taken place. */ - if (newsect->compress_status == COMPRESS_SECTION_DONE) - { - if (name[1] != 'z') - { - unsigned int len = strlen (name); - - new_name = bfd_alloc (abfd, len + 2); - if (new_name == NULL) - return FALSE; - new_name[0] = '.'; - new_name[1] = 'z'; - memcpy (new_name + 2, name + 1, len); - } - } - break; - case decompress: + } + else + { if (!bfd_init_section_decompress_status (abfd, newsect)) { (*_bfd_error_handler) @@ -1095,6 +1088,13 @@ _bfd_elf_make_section_from_shdr (bfd *abfd, abfd, name); return FALSE; } + } + + new_name = NULL; + if (action == decompress + || (action == compress + && (abfd->flags & BFD_COMPRESS_GABI) != 0)) + { if (name[1] == 'z') { unsigned int len = strlen (name); @@ -1105,7 +1105,24 @@ _bfd_elf_make_section_from_shdr (bfd *abfd, new_name[0] = '.'; memcpy (new_name + 1, name + 2, len - 1); } - break; + } + else if (action == compress + && newsect->compress_status == COMPRESS_SECTION_DONE) + { + /* PR binutils/18087: Compression does not always make a section + smaller. So only rename the section when compression has + actually taken place. */ + if (name[1] != 'z') + { + unsigned int len = strlen (name); + + new_name = bfd_alloc (abfd, len + 2); + if (new_name == NULL) + return FALSE; + new_name[0] = '.'; + new_name[1] = 'z'; + memcpy (new_name + 2, name + 1, len); + } } if (new_name != NULL) bfd_rename_section (abfd, newsect, new_name); -- cgit v1.1