diff options
| -rw-r--r-- | gold/ChangeLog | 21 | ||||
| -rw-r--r-- | gold/layout.cc | 90 | ||||
| -rw-r--r-- | gold/layout.h | 20 | ||||
| -rw-r--r-- | gold/options.h | 4 | ||||
| -rw-r--r-- | gold/testsuite/Makefile.am | 12 | ||||
| -rw-r--r-- | gold/testsuite/Makefile.in | 14 | ||||
| -rw-r--r-- | gold/testsuite/keep_text_section_prefix.cc | 52 | ||||
| -rwxr-xr-x | gold/testsuite/keep_text_section_prefix.sh | 77 |
8 files changed, 272 insertions, 18 deletions
diff --git a/gold/ChangeLog b/gold/ChangeLog index 64d6cba..8740462 100644 --- a/gold/ChangeLog +++ b/gold/ChangeLog @@ -1,3 +1,24 @@ +2018-03-07 Sriraman Tallam <tmsriram@google.com> + + * layout.cc (Layout::default_section_order): Check for text section + prefixes. + (Layout::text_section_name_mapping): New static member. + (Layout::text_section_name_mapping_count): New static member. + (Layout::match_section_name): New static function. + (Layout::output_section_name): Check for text section prefixes. + * layout.h (Output_section_order::ORDER_TEXT_HOT): New enum value. + (Output_section_order::ORDER_TEXT_STARTUP): New enum value. + (Output_section_order::ORDER_TEXT_EXIT): New enum value. + (Output_section_order::ORDER_TEXT_UNLIKELY): New enum value. + (Layout::text_section_name_mapping): New static member. + (Layout::text_section_name_mapping_count): New static member. + (Layout::match_section_name): New static function. + * options.h (keep_text_section_prefix): New -z option. + * testsuite/Makefile.am (keep_text_section_prefix): New test. + * testsuite/Makefile.in: Regenerate. + * testsuite/keep_text_section_prefix.cc: New test source. + * testsuite/keep_text_section_prefix.sh: New test script. + 2018-02-22 Sriraman Tallam <tmsriram@google.com> * plugin.cc (get_wrap_symbols): New plugin interface. diff --git a/gold/layout.cc b/gold/layout.cc index 0ec7278..f5fe805 100644 --- a/gold/layout.cc +++ b/gold/layout.cc @@ -1905,6 +1905,19 @@ Layout::default_section_order(Output_section* os, bool is_relro_local) return ORDER_INIT; else if (strcmp(os->name(), ".fini") == 0) return ORDER_FINI; + else if (parameters->options().keep_text_section_prefix()) + { + // -z,keep-text-section-prefix introduces additional + // output sections. + if (strcmp(os->name(), ".text.hot") == 0) + return ORDER_TEXT_HOT; + else if (strcmp(os->name(), ".text.startup") == 0) + return ORDER_TEXT_STARTUP; + else if (strcmp(os->name(), ".text.exit") == 0) + return ORDER_TEXT_EXIT; + else if (strcmp(os->name(), ".text.unlikely") == 0) + return ORDER_TEXT_UNLIKELY; + } } return is_execinstr ? ORDER_TEXT : ORDER_READONLY; } @@ -5134,6 +5147,20 @@ const Layout::Section_name_mapping Layout::section_name_mapping[] = MAPPING_INIT(".ARM.exidx", ".ARM.exidx"), MAPPING_INIT(".gnu.linkonce.armexidx.", ".ARM.exidx"), }; + +// Mapping for ".text" section prefixes with -z,keep-text-section-prefix. +const Layout::Section_name_mapping Layout::text_section_name_mapping[] = +{ + MAPPING_INIT(".text.hot.", ".text.hot"), + MAPPING_INIT_EXACT(".text.hot", ".text.hot"), + MAPPING_INIT(".text.unlikely.", ".text.unlikely"), + MAPPING_INIT_EXACT(".text.unlikely", ".text.unlikely"), + MAPPING_INIT(".text.startup.", ".text.startup"), + MAPPING_INIT_EXACT(".text.startup", ".text.startup"), + MAPPING_INIT(".text.exit.", ".text.exit"), + MAPPING_INIT_EXACT(".text.exit", ".text.exit"), + MAPPING_INIT(".text.", ".text"), +}; #undef MAPPING_INIT #undef MAPPING_INIT_EXACT @@ -5141,6 +5168,39 @@ const int Layout::section_name_mapping_count = (sizeof(Layout::section_name_mapping) / sizeof(Layout::section_name_mapping[0])); +const int Layout::text_section_name_mapping_count = + (sizeof(Layout::text_section_name_mapping) + / sizeof(Layout::text_section_name_mapping[0])); + +// Find section name NAME in PSNM and return the mapped name if found +// with the length set in PLEN. +const char * +Layout::match_section_name(const Layout::Section_name_mapping* psnm, + const int count, + const char* name, size_t* plen) +{ + for (int i = 0; i < count; ++i, ++psnm) + { + if (psnm->fromlen > 0) + { + if (strncmp(name, psnm->from, psnm->fromlen) == 0) + { + *plen = psnm->tolen; + return psnm->to; + } + } + else + { + if (strcmp(name, psnm->from) == 0) + { + *plen = psnm->tolen; + return psnm->to; + } + } + } + return NULL; +} + // Choose the output section name to use given an input section name. // Set *PLEN to the length of the name. *PLEN is initialized to the // length of NAME. @@ -5184,27 +5244,21 @@ Layout::output_section_name(const Relobj* relobj, const char* name, // not found in the table, we simply use it as the output section // name. - const Section_name_mapping* psnm = section_name_mapping; - for (int i = 0; i < section_name_mapping_count; ++i, ++psnm) + if (parameters->options().keep_text_section_prefix() + && is_prefix_of(".text", name)) { - if (psnm->fromlen > 0) - { - if (strncmp(name, psnm->from, psnm->fromlen) == 0) - { - *plen = psnm->tolen; - return psnm->to; - } - } - else - { - if (strcmp(name, psnm->from) == 0) - { - *plen = psnm->tolen; - return psnm->to; - } - } + const char* match = match_section_name(text_section_name_mapping, + text_section_name_mapping_count, + name, plen); + if (match != NULL) + return match; } + const char* match = match_section_name(section_name_mapping, + section_name_mapping_count, name, plen); + if (match != NULL) + return match; + // As an additional complication, .ctors sections are output in // either .ctors or .init_array sections, and .dtors sections are // output in either .dtors or .fini_array sections. diff --git a/gold/layout.h b/gold/layout.h index bbdc162..0c34d3d 100644 --- a/gold/layout.h +++ b/gold/layout.h @@ -422,9 +422,21 @@ enum Output_section_order // The PLT. ORDER_PLT, + // The hot text sections, prefixed by .text.hot. + ORDER_TEXT_HOT, + // The regular text sections. ORDER_TEXT, + // The startup text sections, prefixed by .text.startup. + ORDER_TEXT_STARTUP, + + // The startup text sections, prefixed by .text.startup. + ORDER_TEXT_EXIT, + + // The unlikely text sections, prefixed by .text.unlikely. + ORDER_TEXT_UNLIKELY, + // The .fini section. ORDER_FINI, @@ -1015,6 +1027,14 @@ class Layout }; static const Section_name_mapping section_name_mapping[]; static const int section_name_mapping_count; + static const Section_name_mapping text_section_name_mapping[]; + static const int text_section_name_mapping_count; + + // Find section name NAME in map and return the mapped name if found + // with the length set in PLEN. + static const char* match_section_name(const Section_name_mapping* map, + const int count, const char* name, + size_t* plen); // During a relocatable link, a list of group sections and // signatures. diff --git a/gold/options.h b/gold/options.h index 152b0c1..e75a8bd 100644 --- a/gold/options.h +++ b/gold/options.h @@ -1500,6 +1500,10 @@ class General_options N_("Move .text.unlikely sections to a separate segment."), N_("Do not move .text.unlikely sections to a separate " "segment.")); + DEFINE_bool(keep_text_section_prefix, options::DASH_Z, '\0', false, + N_("Keep .text.hot, .text.startup, .text.exit and .text.unlikely " + "as separate sections in the final binary."), + N_("Merge all .text.* prefix sections.")); public: diff --git a/gold/testsuite/Makefile.am b/gold/testsuite/Makefile.am index bb486ed..a732b53 100644 --- a/gold/testsuite/Makefile.am +++ b/gold/testsuite/Makefile.am @@ -354,6 +354,18 @@ text_unlikely_segment: text_unlikely_segment.o gcctestdir/ld text_unlikely_segment_readelf.stdout: text_unlikely_segment $(TEST_READELF) -Wl $< >$@ +check_SCRIPTS += keep_text_section_prefix.sh +check_DATA += keep_text_section_prefix_readelf.stdout keep_text_section_prefix_nm.stdout +MOSTLYCLEANFILES += keep_text_section_prefix +keep_text_section_prefix.o: keep_text_section_prefix.cc + $(CXXCOMPILE) -O0 -c -ffunction-sections -g -o $@ $< +keep_text_section_prefix: keep_text_section_prefix.o gcctestdir/ld + $(CXXLINK) -Bgcctestdir/ -Wl,-z,keep-text-section-prefix keep_text_section_prefix.o +keep_text_section_prefix_readelf.stdout: keep_text_section_prefix + $(TEST_READELF) -Wl $< >$@ +keep_text_section_prefix_nm.stdout: keep_text_section_prefix + $(TEST_NM) -n $< >$@ + check_PROGRAMS += icf_virtual_function_folding_test MOSTLYCLEANFILES += icf_virtual_function_folding_test icf_virtual_function_folding_test.map icf_virtual_function_folding_test.o: icf_virtual_function_folding_test.cc diff --git a/gold/testsuite/Makefile.in b/gold/testsuite/Makefile.in index ec851d5..6f61eae 100644 --- a/gold/testsuite/Makefile.in +++ b/gold/testsuite/Makefile.in @@ -101,6 +101,7 @@ check_PROGRAMS = $(am__EXEEXT_1) $(am__EXEEXT_2) $(am__EXEEXT_3) \ @GCC_TRUE@@NATIVE_LINKER_TRUE@ text_section_grouping.sh \ @GCC_TRUE@@NATIVE_LINKER_TRUE@ section_sorting_name.sh \ @GCC_TRUE@@NATIVE_LINKER_TRUE@ text_unlikely_segment.sh \ +@GCC_TRUE@@NATIVE_LINKER_TRUE@ keep_text_section_prefix.sh \ @GCC_TRUE@@NATIVE_LINKER_TRUE@ icf_preemptible_functions_test.sh \ @GCC_TRUE@@NATIVE_LINKER_TRUE@ icf_string_merge_test.sh \ @GCC_TRUE@@NATIVE_LINKER_TRUE@ icf_sht_rel_addend_test.sh \ @@ -129,6 +130,8 @@ check_PROGRAMS = $(am__EXEEXT_1) $(am__EXEEXT_2) $(am__EXEEXT_3) \ @GCC_TRUE@@NATIVE_LINKER_TRUE@ text_section_no_grouping.stdout \ @GCC_TRUE@@NATIVE_LINKER_TRUE@ section_sorting_name.stdout \ @GCC_TRUE@@NATIVE_LINKER_TRUE@ text_unlikely_segment_readelf.stdout \ +@GCC_TRUE@@NATIVE_LINKER_TRUE@ keep_text_section_prefix_readelf.stdout \ +@GCC_TRUE@@NATIVE_LINKER_TRUE@ keep_text_section_prefix_nm.stdout \ @GCC_TRUE@@NATIVE_LINKER_TRUE@ icf_preemptible_functions_test.stdout \ @GCC_TRUE@@NATIVE_LINKER_TRUE@ icf_string_merge_test.stdout \ @GCC_TRUE@@NATIVE_LINKER_TRUE@ icf_sht_rel_addend_test.stdout \ @@ -155,6 +158,7 @@ check_PROGRAMS = $(am__EXEEXT_1) $(am__EXEEXT_2) $(am__EXEEXT_3) \ @GCC_TRUE@@NATIVE_LINKER_TRUE@ text_section_no_grouping \ @GCC_TRUE@@NATIVE_LINKER_TRUE@ section_sorting_name \ @GCC_TRUE@@NATIVE_LINKER_TRUE@ text_unlikely_segment \ +@GCC_TRUE@@NATIVE_LINKER_TRUE@ keep_text_section_prefix \ @GCC_TRUE@@NATIVE_LINKER_TRUE@ icf_virtual_function_folding_test \ @GCC_TRUE@@NATIVE_LINKER_TRUE@ icf_virtual_function_folding_test.map \ @GCC_TRUE@@NATIVE_LINKER_TRUE@ icf_preemptible_functions_test \ @@ -5233,6 +5237,8 @@ section_sorting_name.sh.log: section_sorting_name.sh @p='section_sorting_name.sh'; $(am__check_pre) $(LOG_COMPILE) "$$tst" $(am__check_post) text_unlikely_segment.sh.log: text_unlikely_segment.sh @p='text_unlikely_segment.sh'; $(am__check_pre) $(LOG_COMPILE) "$$tst" $(am__check_post) +keep_text_section_prefix.sh.log: keep_text_section_prefix.sh + @p='keep_text_section_prefix.sh'; $(am__check_pre) $(LOG_COMPILE) "$$tst" $(am__check_post) icf_preemptible_functions_test.sh.log: icf_preemptible_functions_test.sh @p='icf_preemptible_functions_test.sh'; $(am__check_pre) $(LOG_COMPILE) "$$tst" $(am__check_post) icf_string_merge_test.sh.log: icf_string_merge_test.sh @@ -6108,6 +6114,14 @@ uninstall-am: @GCC_TRUE@@NATIVE_LINKER_TRUE@ $(CXXLINK) -Bgcctestdir/ -Wl,-z,text-unlikely-segment text_unlikely_segment.o @GCC_TRUE@@NATIVE_LINKER_TRUE@text_unlikely_segment_readelf.stdout: text_unlikely_segment @GCC_TRUE@@NATIVE_LINKER_TRUE@ $(TEST_READELF) -Wl $< >$@ +@GCC_TRUE@@NATIVE_LINKER_TRUE@keep_text_section_prefix.o: keep_text_section_prefix.cc +@GCC_TRUE@@NATIVE_LINKER_TRUE@ $(CXXCOMPILE) -O0 -c -ffunction-sections -g -o $@ $< +@GCC_TRUE@@NATIVE_LINKER_TRUE@keep_text_section_prefix: keep_text_section_prefix.o gcctestdir/ld +@GCC_TRUE@@NATIVE_LINKER_TRUE@ $(CXXLINK) -Bgcctestdir/ -Wl,-z,keep-text-section-prefix keep_text_section_prefix.o +@GCC_TRUE@@NATIVE_LINKER_TRUE@keep_text_section_prefix_readelf.stdout: keep_text_section_prefix +@GCC_TRUE@@NATIVE_LINKER_TRUE@ $(TEST_READELF) -Wl $< >$@ +@GCC_TRUE@@NATIVE_LINKER_TRUE@keep_text_section_prefix_nm.stdout: keep_text_section_prefix +@GCC_TRUE@@NATIVE_LINKER_TRUE@ $(TEST_NM) -n $< >$@ @GCC_TRUE@@NATIVE_LINKER_TRUE@icf_virtual_function_folding_test.o: icf_virtual_function_folding_test.cc @GCC_TRUE@@NATIVE_LINKER_TRUE@ $(CXXCOMPILE) -O0 -c -ffunction-sections -fPIE -g -o $@ $< @GCC_TRUE@@NATIVE_LINKER_TRUE@icf_virtual_function_folding_test: icf_virtual_function_folding_test.o gcctestdir/ld diff --git a/gold/testsuite/keep_text_section_prefix.cc b/gold/testsuite/keep_text_section_prefix.cc new file mode 100644 index 0000000..1395d4c --- /dev/null +++ b/gold/testsuite/keep_text_section_prefix.cc @@ -0,0 +1,52 @@ +/* keep_text_section_prefix.cc -- a test case for gold + + Copyright (C) 2018 onwards Free Software Foundation, Inc. + Written by Sriraman Tallam <tmsriram@google.com> + + This file is part of gold. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, + MA 02110-1301, USA. */ + +extern "C" { +__attribute__((section(".text.unlikely.foo"))) +int unlikely_foo(void) { + return 0; +} + +__attribute__((section(".text.hot.foo"))) +int hot_foo(void) { + return 0; +} + +__attribute__((section(".text.startup.foo"))) +int startup_foo(void) { + return 0; +} + +__attribute__((section(".text.exit.foo"))) +int exit_foo(void) { + return 0; +} + +__attribute__((section(".text.foo"))) +int regular_foo(void) { + return 0; +} + +int main(void) { + return 0; +} +} diff --git a/gold/testsuite/keep_text_section_prefix.sh b/gold/testsuite/keep_text_section_prefix.sh new file mode 100755 index 0000000..44a2b47 --- /dev/null +++ b/gold/testsuite/keep_text_section_prefix.sh @@ -0,0 +1,77 @@ +#!/bin/sh + +# keep_text_section_prefix.sh -- test + +# Copyright (C) 2018 Free Software Foundation, Inc. +# Written by Sriraman Tallam <tmsriram@google.com>. + +# This file is part of gold. + +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 3 of the License, or +# (at your option) any later version. + +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. + +# You should have received a copy of the GNU General Public License +# along with this program; if not, write to the Free Software +# Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, +# MA 02110-1301, USA. + +# The goal of this program is to verify if .text sections are separated +# according to their prefix. .text.hot, .text.unlikely, .text.startup and +# .text.exit must be separated in the final binary. + +set -e + +check() +{ + awk " +BEGIN { saw1 = 0; saw2 = 0; err = 0; } +/.*$2\$/ { saw1 = 1; } +/.*$3\$/ { + saw2 = 1; + if (!saw1) + { + printf \"layout of $2 and $3 is not right\\n\"; + err = 1; + exit 1; + } + } +END { + if (!saw1 && !err) + { + printf \"did not see $2\\n\"; + exit 1; + } + if (!saw2 && !err) + { + printf \"did not see $3\\n\"; + exit 1; + } + }" $1 +} + +check_str() +{ + if ! grep -q "$2" "$1" + then + echo "Did not find expected output in $1:" + echo " $2" + echo "" + echo "Actual output below:" + cat "$1" + exit 1 + fi +} + +check_str keep_text_section_prefix_readelf.stdout ".text.hot .text .text.startup .text.exit .text.unlikely" + +check keep_text_section_prefix_nm.stdout "hot_foo" "regular_foo" +check keep_text_section_prefix_nm.stdout "regular_foo" "startup_foo" +check keep_text_section_prefix_nm.stdout "startup_foo" "exit_foo" +check keep_text_section_prefix_nm.stdout "exit_foo" "unlikely_foo" |