From 0261ec511ac07177fa488133e0bb3c03860977b3 Mon Sep 17 00:00:00 2001 From: "H.J. Lu" Date: Sun, 2 Dec 2018 05:42:36 -0800 Subject: [PATCH 2/2] gold: Get alignment of uncompressed section from ch_addralign The ELF compression header has a field (ch_addralign) that is set to the alignment of the uncompressed section. This way the section itself can have a different alignment than the decompressed section. Update decompress_input_section to get alignment of the decompressed section and use it when merging decompressed strings. PR binutils/23919 * merge.cc (Output_merge_string::do_add_input_section): Get addralign from decompressed_section_contents. * object.cc (build_compressed_section_map): Set info.addralign. (Object::decompressed_section_contents): Add a palign argument and store p->second.addralign in *palign if it isn't NULL. * object.h (Compressed_section_info): Add addralign. (section_is_compressed): Add a palign argument, default it to NULL, store p->second.addralign in *palign if it isn't NULL. (Object::decompressed_section_contents): Likewise. * output.cc (Output_section::add_input_section): Get addralign from section_is_compressed. --- gold/merge.cc | 8 +++++--- gold/object.cc | 11 +++++++++-- gold/object.h | 8 ++++++-- gold/output.cc | 11 ++++++----- 4 files changed, 26 insertions(+), 12 deletions(-) Upstream-Status: Backport [https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=5f6c22aee74f17393b82934a5682d985672e011a] Signed-off-by: Khem Raj diff --git a/gold/merge.cc b/gold/merge.cc index de00ee9ae9..d7de11789f 100644 --- a/gold/merge.cc +++ b/gold/merge.cc @@ -440,9 +440,11 @@ Output_merge_string::do_add_input_section(Relobj* object, { section_size_type sec_len; bool is_new; + uint64_t addralign = this->addralign(); const unsigned char* pdata = object->decompressed_section_contents(shndx, &sec_len, - &is_new); + &is_new, + &addralign); const Char_type* p = reinterpret_cast(pdata); const Char_type* pend = p + sec_len / sizeof(Char_type); @@ -494,7 +496,7 @@ Output_merge_string::do_add_input_section(Relobj* object, // aligned, so each string within the section must retain the same // modulo. uintptr_t init_align_modulo = (reinterpret_cast(pdata) - & (this->addralign() - 1)); + & (addralign - 1)); bool has_misaligned_strings = false; while (p < pend) @@ -503,7 +505,7 @@ Output_merge_string::do_add_input_section(Relobj* object, // Within merge input section each string must be aligned. if (len != 0 - && ((reinterpret_cast(p) & (this->addralign() - 1)) + && ((reinterpret_cast(p) & (addralign - 1)) != init_align_modulo)) has_misaligned_strings = true; diff --git a/gold/object.cc b/gold/object.cc index 374340fa16..711793e5e4 100644 --- a/gold/object.cc +++ b/gold/object.cc @@ -751,11 +751,13 @@ build_compressed_section_map( const unsigned char* contents = obj->section_contents(i, &len, false); uint64_t uncompressed_size; + Compressed_section_info info; if (is_zcompressed) { // Skip over the ".zdebug" prefix. name += 7; uncompressed_size = get_uncompressed_size(contents, len); + info.addralign = shdr.get_sh_addralign(); } else { @@ -763,8 +765,8 @@ build_compressed_section_map( name += 6; elfcpp::Chdr chdr(contents); uncompressed_size = chdr.get_ch_size(); + info.addralign = chdr.get_ch_addralign(); } - Compressed_section_info info; info.size = convert_to_section_size_type(uncompressed_size); info.flag = shdr.get_sh_flags(); info.contents = NULL; @@ -3060,7 +3062,8 @@ const unsigned char* Object::decompressed_section_contents( unsigned int shndx, section_size_type* plen, - bool* is_new) + bool* is_new, + uint64_t* palign) { section_size_type buffer_size; const unsigned char* buffer = this->do_section_contents(shndx, &buffer_size, @@ -3087,6 +3090,8 @@ Object::decompressed_section_contents( { *plen = uncompressed_size; *is_new = false; + if (palign != NULL) + *palign = p->second.addralign; return p->second.contents; } @@ -3108,6 +3113,8 @@ Object::decompressed_section_contents( // once in this pass. *plen = uncompressed_size; *is_new = true; + if (palign != NULL) + *palign = p->second.addralign; return uncompressed_data; } diff --git a/gold/object.h b/gold/object.h index 0b786a5471..b99548463d 100644 --- a/gold/object.h +++ b/gold/object.h @@ -373,6 +373,7 @@ struct Compressed_section_info { section_size_type size; elfcpp::Elf_Xword flag; + uint64_t addralign; const unsigned char* contents; }; typedef std::map Compressed_section_map; @@ -808,7 +809,8 @@ class Object bool section_is_compressed(unsigned int shndx, - section_size_type* uncompressed_size) const + section_size_type* uncompressed_size, + elfcpp::Elf_Xword* palign = NULL) const { if (this->compressed_sections_ == NULL) return false; @@ -818,6 +820,8 @@ class Object { if (uncompressed_size != NULL) *uncompressed_size = p->second.size; + if (palign != NULL) + *palign = p->second.addralign; return true; } return false; @@ -828,7 +832,7 @@ class Object // by the caller. const unsigned char* decompressed_section_contents(unsigned int shndx, section_size_type* plen, - bool* is_cached); + bool* is_cached, uint64_t* palign = NULL); // Discard any buffers of decompressed sections. This is done // at the end of the Add_symbols task. diff --git a/gold/output.cc b/gold/output.cc index 1701db1c99..75ac3bcf97 100644 --- a/gold/output.cc +++ b/gold/output.cc @@ -2448,7 +2448,13 @@ Output_section::add_input_section(Layout* layout, unsigned int reloc_shndx, bool have_sections_script) { + section_size_type input_section_size = shdr.get_sh_size(); + section_size_type uncompressed_size; elfcpp::Elf_Xword addralign = shdr.get_sh_addralign(); + if (object->section_is_compressed(shndx, &uncompressed_size, + &addralign)) + input_section_size = uncompressed_size; + if ((addralign & (addralign - 1)) != 0) { object->error(_("invalid alignment %lu for section \"%s\""), @@ -2498,11 +2504,6 @@ Output_section::add_input_section(Layout* layout, } } - section_size_type input_section_size = shdr.get_sh_size(); - section_size_type uncompressed_size; - if (object->section_is_compressed(shndx, &uncompressed_size)) - input_section_size = uncompressed_size; - off_t offset_in_section; if (this->has_fixed_layout()) -- 2.20.1