From 36171d64bf8c2abf7951c98d655f4c5695b024f1 Mon Sep 17 00:00:00 2001 From: Cary Coutant Date: Tue, 14 Sep 2010 21:44:21 +0000 Subject: [PATCH] * x86_64.cc (Target_x86_64::saw_tls_block_reloc_): Remove member. (Target_x86_64::Relocate::relocate_tls): Replace check for saw_tls_block_reloc_ with test for executable section. --- gold/ChangeLog | 6 +++++ gold/x86_64.cc | 73 ++++++++++++++++++++++++++++---------------------- 2 files changed, 47 insertions(+), 32 deletions(-) diff --git a/gold/ChangeLog b/gold/ChangeLog index 6c78bcfdc8c..c0dbc263bf8 100644 --- a/gold/ChangeLog +++ b/gold/ChangeLog @@ -1,3 +1,9 @@ +2010-09-14 Cary Coutant + + * x86_64.cc (Target_x86_64::saw_tls_block_reloc_): Remove member. + (Target_x86_64::Relocate::relocate_tls): Replace check for + saw_tls_block_reloc_ with test for executable section. + 2010-09-12 Cary Coutant * symtab.h (Symbol::needs_dynamic_reloc): Non-PIC calls from diff --git a/gold/x86_64.cc b/gold/x86_64.cc index 4fec45ce6bd..1396fb39283 100644 --- a/gold/x86_64.cc +++ b/gold/x86_64.cc @@ -420,7 +420,7 @@ class Target_x86_64 : public Target_freebsd<64, false> { public: Relocate() - : skip_call_tls_get_addr_(false), saw_tls_block_reloc_(false) + : skip_call_tls_get_addr_(false) { } ~Relocate() @@ -511,12 +511,6 @@ class Target_x86_64 : public Target_freebsd<64, false> // This is set if we should skip the next reloc, which should be a // PLT32 reloc against ___tls_get_addr. bool skip_call_tls_get_addr_; - - // This is set if we see a relocation which could load the address - // of the TLS block. Whether we see such a relocation determines - // how we handle the R_X86_64_DTPOFF32 relocation, which is used - // in debugging sections. - bool saw_tls_block_reloc_; }; // A class which returns the size required for a relocation type, @@ -2492,18 +2486,29 @@ Target_x86_64::Relocate::relocate_tls(const Relocate_info<64, false>* relinfo, const Sized_relobj<64, false>* object = relinfo->object; const elfcpp::Elf_Xword addend = rela.get_r_addend(); + elfcpp::Shdr<64, false> data_shdr(relinfo->data_shdr); + bool is_executable = (data_shdr.get_sh_flags() & elfcpp::SHF_EXECINSTR) != 0; elfcpp::Elf_types<64>::Elf_Addr value = psymval->value(relinfo->object, 0); const bool is_final = (gsym == NULL ? !parameters->options().shared() : gsym->final_value_is_known()); - const tls::Tls_optimization optimized_type + tls::Tls_optimization optimized_type = Target_x86_64::optimize_tls_reloc(is_final, r_type); switch (r_type) { case elfcpp::R_X86_64_TLSGD: // Global-dynamic - this->saw_tls_block_reloc_ = true; + if (!is_executable && optimized_type == tls::TLSOPT_TO_LE) + { + // If this code sequence is used in a non-executable section, + // we will not optimize the R_X86_64_DTPOFF32/64 relocation, + // on the assumption that it's being used by itself in a debug + // section. Therefore, in the unlikely event that the code + // sequence appears in a non-executable section, we simply + // leave it unoptimized. + optimized_type = tls::TLSOPT_NONE; + } if (optimized_type == tls::TLSOPT_TO_LE) { gold_assert(tls_segment != NULL); @@ -2554,7 +2559,11 @@ Target_x86_64::Relocate::relocate_tls(const Relocate_info<64, false>* relinfo, case elfcpp::R_X86_64_GOTPC32_TLSDESC: // Global-dynamic (from ~oliva url) case elfcpp::R_X86_64_TLSDESC_CALL: - this->saw_tls_block_reloc_ = true; + if (!is_executable && optimized_type == tls::TLSOPT_TO_LE) + { + // See above comment for R_X86_64_TLSGD. + optimized_type = tls::TLSOPT_NONE; + } if (optimized_type == tls::TLSOPT_TO_LE) { gold_assert(tls_segment != NULL); @@ -2617,7 +2626,11 @@ Target_x86_64::Relocate::relocate_tls(const Relocate_info<64, false>* relinfo, break; case elfcpp::R_X86_64_TLSLD: // Local-dynamic - this->saw_tls_block_reloc_ = true; + if (!is_executable && optimized_type == tls::TLSOPT_TO_LE) + { + // See above comment for R_X86_64_TLSGD. + optimized_type = tls::TLSOPT_NONE; + } if (optimized_type == tls::TLSOPT_TO_LE) { gold_assert(tls_segment != NULL); @@ -2642,31 +2655,27 @@ Target_x86_64::Relocate::relocate_tls(const Relocate_info<64, false>* relinfo, break; case elfcpp::R_X86_64_DTPOFF32: - if (optimized_type == tls::TLSOPT_TO_LE) - { - // This relocation type is used in debugging information. - // In that case we need to not optimize the value. If we - // haven't seen a TLSLD reloc, then we assume we should not - // optimize this reloc. - if (this->saw_tls_block_reloc_) - { - gold_assert(tls_segment != NULL); - value -= tls_segment->memsz(); - } - } + // This relocation type is used in debugging information. + // In that case we need to not optimize the value. If the + // section is not executable, then we assume we should not + // optimize this reloc. See comments above for R_X86_64_TLSGD, + // R_X86_64_GOTPC32_TLSDESC, R_X86_64_TLSDESC_CALL, and + // R_X86_64_TLSLD. + if (optimized_type == tls::TLSOPT_TO_LE && is_executable) + { + gold_assert(tls_segment != NULL); + value -= tls_segment->memsz(); + } Relocate_functions<64, false>::rela32(view, value, addend); break; case elfcpp::R_X86_64_DTPOFF64: - if (optimized_type == tls::TLSOPT_TO_LE) - { - // See R_X86_64_DTPOFF32, just above, for why we test this. - if (this->saw_tls_block_reloc_) - { - gold_assert(tls_segment != NULL); - value -= tls_segment->memsz(); - } - } + // See R_X86_64_DTPOFF32, just above, for why we check for is_executable. + if (optimized_type == tls::TLSOPT_TO_LE && is_executable) + { + gold_assert(tls_segment != NULL); + value -= tls_segment->memsz(); + } Relocate_functions<64, false>::rela64(view, value, addend); break; -- 2.30.2