From 2646c83243ff84202675ceae2f559c73f0532bec Mon Sep 17 00:00:00 2001 From: tmsriram Date: Thu, 4 Mar 2010 01:33:21 +0000 Subject: [PATCH] * i386.cc (Target_i386::can_check_for_function_pointers): New function. (Scan::possible_function_pointer_reloc): New function. (Scan::local_reloc_may_be_function_pointer): Change to call possible_function_pointer_reloc. (Scan::global_reloc_may_be_function_pointer): Ditto. * icf.h (Icf::check_section_for_function_pointers): Change to reject relocations in ".data.rel.ro._ZTV" section. * testsuite/icf_safe_so_test.sh: Change to pass i386. * testsuite/icf_safe_so_test.cc: Ditto. * testsuite/icf_safe_test.cc: Ditto. * testsuite/icf_safe_test.sh: Ditto. --- gold/ChangeLog | 14 ++++++ gold/i386.cc | 88 +++++++++++++++++++++++++++++++------- gold/icf.h | 1 + gold/testsuite/icf_safe_so_test.cc | 3 +- gold/testsuite/icf_safe_so_test.sh | 64 +++++++++++++++++++++------ gold/testsuite/icf_safe_test.cc | 8 ++-- gold/testsuite/icf_safe_test.sh | 6 +-- 7 files changed, 148 insertions(+), 36 deletions(-) diff --git a/gold/ChangeLog b/gold/ChangeLog index 2610909fe6..33b730768b 100644 --- a/gold/ChangeLog +++ b/gold/ChangeLog @@ -1,3 +1,17 @@ +2010-03-03 Sriraman Tallam + + * i386.cc (Target_i386::can_check_for_function_pointers): New function. + (Scan::possible_function_pointer_reloc): New function. + (Scan::local_reloc_may_be_function_pointer): Change to call + possible_function_pointer_reloc. + (Scan::global_reloc_may_be_function_pointer): Ditto. + * icf.h (Icf::check_section_for_function_pointers): Change to reject + relocations in ".data.rel.ro._ZTV" section. + * testsuite/icf_safe_so_test.sh: Change to pass i386. + * testsuite/icf_safe_so_test.cc: Ditto. + * testsuite/icf_safe_test.cc: Ditto. + * testsuite/icf_safe_test.sh: Ditto. + 2010-03-03 Viktor Kutuzov Ian Lance Taylor diff --git a/gold/i386.cc b/gold/i386.cc index eb4ef0abc7..e7b700c37f 100644 --- a/gold/i386.cc +++ b/gold/i386.cc @@ -64,6 +64,10 @@ class Target_i386 : public Target_freebsd<32, false> got_mod_index_offset_(-1U), tls_base_symbol_defined_(false) { } + inline bool + can_check_for_function_pointers() const + { return true; } + // Process the relocations to determine unreferenced sections for // garbage collection. void @@ -203,24 +207,27 @@ class Target_i386 : public Target_freebsd<32, false> Symbol* gsym); inline bool - local_reloc_may_be_function_pointer(Symbol_table* , Layout* , Target_i386* , - Sized_relobj<32, false>* , - unsigned int , - Output_section* , - const elfcpp::Rel<32, false>& , - unsigned int , - const elfcpp::Sym<32, false>&) - { return false; } + local_reloc_may_be_function_pointer(Symbol_table* symtab, Layout* layout, + Target_i386* target, + Sized_relobj<32, false>* object, + unsigned int data_shndx, + Output_section* output_section, + const elfcpp::Rel<32, false>& reloc, + unsigned int r_type, + const elfcpp::Sym<32, false>& lsym); + + inline bool + global_reloc_may_be_function_pointer(Symbol_table* symtab, Layout* layout, + Target_i386* target, + Sized_relobj<32, false>* object, + unsigned int data_shndx, + Output_section* output_section, + const elfcpp::Rel<32, false>& reloc, + unsigned int r_type, + Symbol* gsym); inline bool - global_reloc_may_be_function_pointer(Symbol_table* , Layout* , - Target_i386* , - Sized_relobj<32, false>* , - unsigned int , - Output_section* , - const elfcpp::Rel<32, false>& , - unsigned int , Symbol*) - { return false; } + possible_function_pointer_reloc(unsigned int r_type); static void unsupported_reloc_local(Sized_relobj<32, false>*, unsigned int r_type); @@ -1234,6 +1241,55 @@ Target_i386::Scan::unsupported_reloc_global(Sized_relobj<32, false>* object, object->name().c_str(), r_type, gsym->demangled_name().c_str()); } +inline bool +Target_i386::Scan::possible_function_pointer_reloc(unsigned int r_type) +{ + switch (r_type) + { + case elfcpp::R_386_32: + case elfcpp::R_386_16: + case elfcpp::R_386_8: + case elfcpp::R_386_GOTOFF: + case elfcpp::R_386_GOT32: + { + return true; + } + default: + return false; + } + return false; +} + +inline bool +Target_i386::Scan::local_reloc_may_be_function_pointer( + Symbol_table* , + Layout* , + Target_i386* , + Sized_relobj<32, false>* , + unsigned int , + Output_section* , + const elfcpp::Rel<32, false>& , + unsigned int r_type, + const elfcpp::Sym<32, false>&) +{ + return possible_function_pointer_reloc(r_type); +} + +inline bool +Target_i386::Scan::global_reloc_may_be_function_pointer( + Symbol_table* , + Layout* , + Target_i386* , + Sized_relobj<32, false>* , + unsigned int , + Output_section* , + const elfcpp::Rel<32, false>& , + unsigned int r_type, + Symbol*) +{ + return possible_function_pointer_reloc(r_type); +} + // Scan a relocation for a global symbol. inline void diff --git a/gold/icf.h b/gold/icf.h index c1db8e586f..27bbbba0fe 100644 --- a/gold/icf.h +++ b/gold/icf.h @@ -127,6 +127,7 @@ class Icf return (parameters->options().icf_safe_folding() && target->can_check_for_function_pointers() && !is_prefix_of(".rodata._ZTV", section_name.c_str()) + && !is_prefix_of(".data.rel.ro._ZTV", section_name.c_str()) && !is_prefix_of(".eh_frame", section_name.c_str())); } diff --git a/gold/testsuite/icf_safe_so_test.cc b/gold/testsuite/icf_safe_so_test.cc index 5e4453b75e..0f50ad61ad 100644 --- a/gold/testsuite/icf_safe_so_test.cc +++ b/gold/testsuite/icf_safe_so_test.cc @@ -24,7 +24,8 @@ // in safe mode correctly folds functions in a shared object. The // foo_* functions below should not be folded. For x86-64, // foo_glob and bar_glob should be folded as their function pointers -// are addresses of PLT entries in shared objects. +// are addresses of PLT entries in shared objects. For 32-bit X86, +// the hidden protected and internal symbols can be folded. int __attribute__ ((visibility ("protected"))) foo_prot() diff --git a/gold/testsuite/icf_safe_so_test.sh b/gold/testsuite/icf_safe_so_test.sh index db2e73ebc1..262daefd09 100755 --- a/gold/testsuite/icf_safe_so_test.sh +++ b/gold/testsuite/icf_safe_so_test.sh @@ -25,8 +25,26 @@ # to verify if identical code folding in safe mode correctly folds # functions in a shared object. +error_if_symbol_absent() +{ + is_symbol_present $1 $2 + if [ $? != 0 ]; + then + echo "Symbol" $2 "not present, possibly folded." + exit 1 + fi +} + +is_symbol_present() +{ + result=`grep $2 $1` + return $? +} + check_nofold() { + error_if_symbol_absent $1 $2 + error_if_symbol_absent $1 $3 func_addr_1=`grep $2 $1 | awk '{print $1}'` func_addr_2=`grep $3 $1 | awk '{print $1}'` if [ $func_addr_1 = $func_addr_2 ]; @@ -38,6 +56,18 @@ check_nofold() check_fold() { + is_symbol_present $1 $2 + if [ $? != 0 ]; + then + return 0 + fi + + is_symbol_present $1 $3 + if [ $? != 0 ]; + then + return 0 + fi + func_addr_1=`grep $2 $1 | awk '{print $1}'` func_addr_2=`grep $3 $1 | awk '{print $1}'` if [ $func_addr_1 != $func_addr_2 ]; @@ -49,21 +79,31 @@ check_fold() arch_specific_safe_fold() { - grep_x86_64=`grep -q "Advanced Micro Devices X86-64" $2` - if [ $? == 0 ]; + if [ $1 == 0 ]; then - check_fold $1 $3 $4 + check_fold $2 $3 $4 else - check_nofold $1 $3 $4 + check_nofold $2 $3 $4 fi } -check_nofold icf_safe_so_test_1.stdout "foo_prot" "foo_hidden" -check_nofold icf_safe_so_test_1.stdout "foo_prot" "foo_internal" -check_nofold icf_safe_so_test_1.stdout "foo_prot" "foo_static" -check_nofold icf_safe_so_test_1.stdout "foo_hidden" "foo_internal" -check_nofold icf_safe_so_test_1.stdout "foo_hidden" "foo_static" -check_nofold icf_safe_so_test_1.stdout "foo_internal" "foo_static" -arch_specific_safe_fold icf_safe_so_test_1.stdout icf_safe_so_test_2.stdout \ - "foo_glob" "bar_glob" +X86_32_specific_safe_fold() +{ + grep -q -e "Intel 80386" $1 >& /dev/null + arch_specific_safe_fold $? $2 $3 $4 +} +X86_64_specific_safe_fold() +{ + grep -q -e "Advanced Micro Devices X86-64" $1 >& /dev/null + arch_specific_safe_fold $? $2 $3 $4 +} + +X86_32_specific_safe_fold icf_safe_so_test_2.stdout icf_safe_so_test_1.stdout "foo_prot" "foo_hidden" +X86_32_specific_safe_fold icf_safe_so_test_2.stdout icf_safe_so_test_1.stdout "foo_prot" "foo_internal" +X86_32_specific_safe_fold icf_safe_so_test_2.stdout icf_safe_so_test_1.stdout "foo_prot" "foo_static" +X86_32_specific_safe_fold icf_safe_so_test_2.stdout icf_safe_so_test_1.stdout "foo_hidden" "foo_internal" +X86_32_specific_safe_fold icf_safe_so_test_2.stdout icf_safe_so_test_1.stdout "foo_hidden" "foo_static" +X86_32_specific_safe_fold icf_safe_so_test_2.stdout icf_safe_so_test_1.stdout "foo_internal" "foo_static" +X86_64_specific_safe_fold icf_safe_so_test_2.stdout icf_safe_so_test_1.stdout \ + "foo_glob" "bar_glob" diff --git a/gold/testsuite/icf_safe_test.cc b/gold/testsuite/icf_safe_test.cc index 3edb86576a..87294dcce9 100644 --- a/gold/testsuite/icf_safe_test.cc +++ b/gold/testsuite/icf_safe_test.cc @@ -22,10 +22,10 @@ // The goal of this program is to verify if identical code folding // in safe mode correctly folds only ctors and dtors. kept_func_1 must -// not be folded into kept_func_2 other than for X86-64 which can -// use relocation types to determine if function pointers are taken. -// kept_func_3 should never be folded as its pointer is taken. The ctor -// and dtor of class A must be folded. +// not be folded into kept_func_2 other than for X86 (32 and 64 bit) +// which can use relocation types to determine if function pointers are +// taken. kept_func_3 should never be folded as its pointer is taken. +// The ctor and dtor of class A must be folded. class A { diff --git a/gold/testsuite/icf_safe_test.sh b/gold/testsuite/icf_safe_test.sh index 540dcc2685..23e4e295cc 100755 --- a/gold/testsuite/icf_safe_test.sh +++ b/gold/testsuite/icf_safe_test.sh @@ -22,8 +22,8 @@ # The goal of this program is to verify if --icf=safe works as expected. # File icf_safe_test.cc is in this test. This program checks if only -# ctors and dtors are folded, except for x86-64, which uses relocation -# types to detect if function pointers are taken. +# ctors and dtors are folded, except for x86 (32 and 64 bit), which +# uses relocation types to detect if function pointers are taken. check_nofold() { @@ -49,7 +49,7 @@ check_fold() arch_specific_safe_fold() { - grep_x86_64=`grep -q "Advanced Micro Devices X86-64" $2` + grep_x86=`grep -q -e "Advanced Micro Devices X86-64" -e "Intel 80386" $2` if [ $? == 0 ]; then check_fold $1 $3 $4 -- 2.11.0