From 86f2e683461018af5274634f0b119b39576b17e0 Mon Sep 17 00:00:00 2001 From: Ian Lance Taylor Date: Wed, 19 Sep 2007 06:02:29 +0000 Subject: [PATCH] Let special symbols override existing symbols rather than reinitializing them. --- gold/resolve.cc | 395 ++++++++++++++++++++++++++++++------------------ gold/symtab.cc | 178 +++++++++++++--------- gold/symtab.h | 22 ++- 3 files changed, 378 insertions(+), 217 deletions(-) diff --git a/gold/resolve.cc b/gold/resolve.cc index e5ca6e38c9..599aad46d1 100644 --- a/gold/resolve.cc +++ b/gold/resolve.cc @@ -51,6 +51,25 @@ Sized_symbol::override(const elfcpp::Sym& sym, this->symsize_ = sym.get_st_size(); } +// The resolve functions build a little code for each symbol. +// Bit 0: 0 for global, 1 for weak. +// Bit 1: 0 for regular object, 1 for shared object +// Bits 2-3: 0 for normal, 1 for undefined, 2 for common +// This gives us values from 0 to 11. + +static const int global_or_weak_shift = 0; +static const unsigned int global_flag = 0 << global_or_weak_shift; +static const unsigned int weak_flag = 1 << global_or_weak_shift; + +static const int regular_or_dynamic_shift = 1; +static const unsigned int regular_flag = 0 << regular_or_dynamic_shift; +static const unsigned int dynamic_flag = 1 << regular_or_dynamic_shift; + +static const int def_undef_or_common_shift = 2; +static const unsigned int def_flag = 0 << def_undef_or_common_shift; +static const unsigned int undef_flag = 1 << def_undef_or_common_shift; +static const unsigned int common_flag = 2 << def_undef_or_common_shift; + // Resolve a symbol. This is called the second and subsequent times // we see a symbol. TO is the pre-existing symbol. SYM is the new // symbol, seen in OBJECT. VERSION of the version of SYM. @@ -71,79 +90,26 @@ Symbol_table::resolve(Sized_symbol* to, return; } - // Build a little code for each symbol. - // Bit 0: 0 for global, 1 for weak. - // Bit 1: 0 for regular object, 1 for shared object - // Bits 2-3: 0 for normal, 1 for undefined, 2 for common - // This gives us values from 0 to 11: - - enum - { - DEF = 0, - WEAK_DEF = 1, - DYN_DEF = 2, - DYN_WEAK_DEF = 3, - UNDEF = 4, - WEAK_UNDEF = 5, - DYN_UNDEF = 6, - DYN_WEAK_UNDEF = 7, - COMMON = 8, - WEAK_COMMON = 9, - DYN_COMMON = 10, - DYN_WEAK_COMMON = 11 - }; - - int tobits; - switch (to->binding()) + if (!object->is_dynamic()) { - case elfcpp::STB_GLOBAL: - tobits = 0; - break; - - case elfcpp::STB_WEAK: - tobits = 1; - break; - - case elfcpp::STB_LOCAL: - // We should only see externally visible symbols in the symbol - // table. - gold_unreachable(); - - default: - // Any target which wants to handle STB_LOOS, etc., needs to - // define a resolve method. - gold_unreachable(); + // Record that we've seen this symbol in a regular object. + to->set_in_reg(); + } + else + { + // Record that we've seen this symbol in a dynamic object. + to->set_in_dyn(); } - if (to->source() == Symbol::FROM_OBJECT - && to->object()->is_dynamic()) - tobits |= (1 << 1); - - switch (to->shndx()) - { - case elfcpp::SHN_UNDEF: - tobits |= (1 << 2); - break; - - case elfcpp::SHN_COMMON: - tobits |= (2 << 2); - break; - - default: - if (to->type() == elfcpp::STT_COMMON) - tobits |= (2 << 2); - break; - } - - int frombits; + unsigned int frombits; switch (sym.get_st_bind()) { case elfcpp::STB_GLOBAL: - frombits = 0; + frombits = global_flag; break; case elfcpp::STB_WEAK: - frombits = 1; + frombits = weak_flag; break; case elfcpp::STB_LOCAL: @@ -161,31 +127,101 @@ Symbol_table::resolve(Sized_symbol* to, } if (!object->is_dynamic()) - { - // Record that we've seen this symbol in a regular object. - to->set_in_reg(); - } + frombits |= regular_flag; else - { - frombits |= (1 << 1); - - // Record that we've seen this symbol in a dynamic object. - to->set_in_dyn(); - } + frombits |= dynamic_flag; switch (sym.get_st_shndx()) { case elfcpp::SHN_UNDEF: - frombits |= (1 << 2); + frombits |= undef_flag; break; case elfcpp::SHN_COMMON: - frombits |= (2 << 2); + frombits |= common_flag; break; default: if (sym.get_st_type() == elfcpp::STT_COMMON) - frombits |= (2 << 2); + frombits |= common_flag; + else + frombits |= def_flag; + break; + } + + bool adjust_common_sizes; + if (Symbol_table::should_override(to, frombits, &adjust_common_sizes)) + { + typename Sized_symbol::Size_type tosize = to->symsize(); + + to->override(sym, object, version); + + if (adjust_common_sizes && tosize > to->symsize()) + to->set_symsize(tosize); + } + else + { + if (adjust_common_sizes && sym.get_st_size() > to->symsize()) + to->set_symsize(sym.get_st_size()); + } +} + +// Handle the core of symbol resolution. This is called with the +// existing symbol, TO, and a bitflag describing the new symbol. This +// returns true if we should override the existing symbol with the new +// one, and returns false otherwise. It sets *ADJUST_COMMON_SIZES to +// true if we should set the symbol size to the maximum of the TO and +// FROM sizes. It handles error conditions. + +bool +Symbol_table::should_override(const Symbol* to, unsigned int frombits, + bool* adjust_common_sizes) +{ + *adjust_common_sizes = false; + + unsigned int tobits; + switch (to->binding()) + { + case elfcpp::STB_GLOBAL: + tobits = global_flag; + break; + + case elfcpp::STB_WEAK: + tobits = weak_flag; + break; + + case elfcpp::STB_LOCAL: + // We should only see externally visible symbols in the symbol + // table. + gold_unreachable(); + + default: + // Any target which wants to handle STB_LOOS, etc., needs to + // define a resolve method. + gold_unreachable(); + } + + if (to->source() == Symbol::FROM_OBJECT + && to->object()->is_dynamic()) + tobits |= dynamic_flag; + else + tobits |= regular_flag; + + switch (to->shndx()) + { + case elfcpp::SHN_UNDEF: + tobits |= undef_flag; + break; + + case elfcpp::SHN_COMMON: + tobits |= common_flag; + break; + + default: + if (to->type() == elfcpp::STT_COMMON) + tobits |= common_flag; + else + tobits |= def_flag; break; } @@ -199,14 +235,31 @@ Symbol_table::resolve(Sized_symbol* to, // but that is no easier to understand than this large switch // statement. + // These are the values generated by the bit codes. + enum + { + DEF = global_flag | regular_flag | def_flag, + WEAK_DEF = weak_flag | regular_flag | def_flag, + DYN_DEF = global_flag | dynamic_flag | def_flag, + DYN_WEAK_DEF = weak_flag | dynamic_flag | def_flag, + UNDEF = global_flag | regular_flag | undef_flag, + WEAK_UNDEF = weak_flag | regular_flag | undef_flag, + DYN_UNDEF = global_flag | dynamic_flag | undef_flag, + DYN_WEAK_UNDEF = weak_flag | dynamic_flag | undef_flag, + COMMON = global_flag | regular_flag | common_flag, + WEAK_COMMON = weak_flag | regular_flag | common_flag, + DYN_COMMON = global_flag | dynamic_flag | common_flag, + DYN_WEAK_COMMON = weak_flag | dynamic_flag | common_flag + }; + switch (tobits * 16 + frombits) { case DEF * 16 + DEF: // Two definitions of the same symbol. - fprintf(stderr, "%s: %s: multiple definition of %s\n", - program_name, object->name().c_str(), to->name()); + fprintf(stderr, "%s: multiple definition of %s\n", + program_name, to->name()); // FIXME: Report locations. Record that we have seen an error. - return; + return false; case WEAK_DEF * 16 + DEF: // We've seen a weak definition, and now we see a strong @@ -217,8 +270,7 @@ Symbol_table::resolve(Sized_symbol* to, // are currently compatible with the GNU linker. In the future // we should add a target specific option to change this. // FIXME. - to->override(sym, object, version); - return; + return true; case DYN_DEF * 16 + DEF: case DYN_WEAK_DEF * 16 + DEF: @@ -226,8 +278,7 @@ Symbol_table::resolve(Sized_symbol* to, // definition in a regular object. The definition in the // regular object overrides the definition in the dynamic // object. - to->override(sym, object, version); - return; + return true; case UNDEF * 16 + DEF: case WEAK_UNDEF * 16 + DEF: @@ -235,8 +286,7 @@ Symbol_table::resolve(Sized_symbol* to, case DYN_WEAK_UNDEF * 16 + DEF: // We've seen an undefined reference, and now we see a // definition. We use the definition. - to->override(sym, object, version); - return; + return true; case COMMON * 16 + DEF: case WEAK_COMMON * 16 + DEF: @@ -245,56 +295,51 @@ Symbol_table::resolve(Sized_symbol* to, // We've seen a common symbol and now we see a definition. The // definition overrides. FIXME: We should optionally issue, version a // warning. - to->override(sym, object, version); - return; + return true; case DEF * 16 + WEAK_DEF: case WEAK_DEF * 16 + WEAK_DEF: // We've seen a definition and now we see a weak definition. We // ignore the new weak definition. - return; + return false; case DYN_DEF * 16 + WEAK_DEF: case DYN_WEAK_DEF * 16 + WEAK_DEF: // We've seen a dynamic definition and now we see a regular weak // definition. The regular weak definition overrides. - to->override(sym, object, version); - return; + return true; case UNDEF * 16 + WEAK_DEF: case WEAK_UNDEF * 16 + WEAK_DEF: case DYN_UNDEF * 16 + WEAK_DEF: case DYN_WEAK_UNDEF * 16 + WEAK_DEF: // A weak definition of a currently undefined symbol. - to->override(sym, object, version); - return; + return true; case COMMON * 16 + WEAK_DEF: case WEAK_COMMON * 16 + WEAK_DEF: // A weak definition does not override a common definition. - return; + return false; case DYN_COMMON * 16 + WEAK_DEF: case DYN_WEAK_COMMON * 16 + WEAK_DEF: // A weak definition does override a definition in a dynamic // object. FIXME: We should optionally issue a warning. - to->override(sym, object, version); - return; + return true; case DEF * 16 + DYN_DEF: case WEAK_DEF * 16 + DYN_DEF: case DYN_DEF * 16 + DYN_DEF: case DYN_WEAK_DEF * 16 + DYN_DEF: // Ignore a dynamic definition if we already have a definition. - return; + return false; case UNDEF * 16 + DYN_DEF: case WEAK_UNDEF * 16 + DYN_DEF: case DYN_UNDEF * 16 + DYN_DEF: case DYN_WEAK_UNDEF * 16 + DYN_DEF: // Use a dynamic definition if we have a reference. - to->override(sym, object, version); - return; + return true; case COMMON * 16 + DYN_DEF: case WEAK_COMMON * 16 + DYN_DEF: @@ -302,7 +347,7 @@ Symbol_table::resolve(Sized_symbol* to, case DYN_WEAK_COMMON * 16 + DYN_DEF: // Ignore a dynamic definition if we already have a common // definition. - return; + return false; case DEF * 16 + DYN_WEAK_DEF: case WEAK_DEF * 16 + DYN_WEAK_DEF: @@ -310,15 +355,14 @@ Symbol_table::resolve(Sized_symbol* to, case DYN_WEAK_DEF * 16 + DYN_WEAK_DEF: // Ignore a weak dynamic definition if we already have a // definition. - return; + return false; case UNDEF * 16 + DYN_WEAK_DEF: case WEAK_UNDEF * 16 + DYN_WEAK_DEF: case DYN_UNDEF * 16 + DYN_WEAK_DEF: case DYN_WEAK_UNDEF * 16 + DYN_WEAK_DEF: // Use a weak dynamic definition if we have a reference. - to->override(sym, object, version); - return; + return true; case COMMON * 16 + DYN_WEAK_DEF: case WEAK_COMMON * 16 + DYN_WEAK_DEF: @@ -326,7 +370,7 @@ Symbol_table::resolve(Sized_symbol* to, case DYN_WEAK_COMMON * 16 + DYN_WEAK_DEF: // Ignore a weak dynamic definition if we already have a common // definition. - return; + return false; case DEF * 16 + UNDEF: case WEAK_DEF * 16 + UNDEF: @@ -334,21 +378,20 @@ Symbol_table::resolve(Sized_symbol* to, case DYN_WEAK_DEF * 16 + UNDEF: case UNDEF * 16 + UNDEF: // A new undefined reference tells us nothing. - return; + return false; case WEAK_UNDEF * 16 + UNDEF: case DYN_UNDEF * 16 + UNDEF: case DYN_WEAK_UNDEF * 16 + UNDEF: // A strong undef overrides a dynamic or weak undef. - to->override(sym, object, version); - return; + return true; case COMMON * 16 + UNDEF: case WEAK_COMMON * 16 + UNDEF: case DYN_COMMON * 16 + UNDEF: case DYN_WEAK_COMMON * 16 + UNDEF: // A new undefined reference tells us nothing. - return; + return false; case DEF * 16 + WEAK_UNDEF: case WEAK_DEF * 16 + WEAK_UNDEF: @@ -363,7 +406,7 @@ Symbol_table::resolve(Sized_symbol* to, case DYN_COMMON * 16 + WEAK_UNDEF: case DYN_WEAK_COMMON * 16 + WEAK_UNDEF: // A new weak undefined reference tells us nothing. - return; + return false; case DEF * 16 + DYN_UNDEF: case WEAK_DEF * 16 + DYN_UNDEF: @@ -378,7 +421,7 @@ Symbol_table::resolve(Sized_symbol* to, case DYN_COMMON * 16 + DYN_UNDEF: case DYN_WEAK_COMMON * 16 + DYN_UNDEF: // A new dynamic undefined reference tells us nothing. - return; + return false; case DEF * 16 + DYN_WEAK_UNDEF: case WEAK_DEF * 16 + DYN_WEAK_UNDEF: @@ -393,50 +436,41 @@ Symbol_table::resolve(Sized_symbol* to, case DYN_COMMON * 16 + DYN_WEAK_UNDEF: case DYN_WEAK_COMMON * 16 + DYN_WEAK_UNDEF: // A new weak dynamic undefined reference tells us nothing. - return; + return false; case DEF * 16 + COMMON: // A common symbol does not override a definition. - return; + return false; case WEAK_DEF * 16 + COMMON: case DYN_DEF * 16 + COMMON: case DYN_WEAK_DEF * 16 + COMMON: // A common symbol does override a weak definition or a dynamic // definition. - to->override(sym, object, version); - return; + return true; case UNDEF * 16 + COMMON: case WEAK_UNDEF * 16 + COMMON: case DYN_UNDEF * 16 + COMMON: case DYN_WEAK_UNDEF * 16 + COMMON: // A common symbol is a definition for a reference. - to->override(sym, object, version); - return; + return true; case COMMON * 16 + COMMON: // Set the size to the maximum. - if (sym.get_st_size() > to->symsize()) - to->set_symsize(sym.get_st_size()); - return; + *adjust_common_sizes = true; + return false; case WEAK_COMMON * 16 + COMMON: // I'm not sure just what a weak common symbol means, but // presumably it can be overridden by a regular common symbol. - to->override(sym, object, version); - return; + return true; case DYN_COMMON * 16 + COMMON: case DYN_WEAK_COMMON * 16 + COMMON: - { - // Use the real common symbol, but adjust the size if necessary. - typename Sized_symbol::Size_type symsize = to->symsize(); - to->override(sym, object, version); - if (to->symsize() < symsize) - to->set_symsize(symsize); - } - return; + // Use the real common symbol, but adjust the size if necessary. + *adjust_common_sizes = true; + return true; case DEF * 16 + WEAK_COMMON: case WEAK_DEF * 16 + WEAK_COMMON: @@ -444,15 +478,14 @@ Symbol_table::resolve(Sized_symbol* to, case DYN_WEAK_DEF * 16 + WEAK_COMMON: // Whatever a weak common symbol is, it won't override a // definition. - return; + return false; case UNDEF * 16 + WEAK_COMMON: case WEAK_UNDEF * 16 + WEAK_COMMON: case DYN_UNDEF * 16 + WEAK_COMMON: case DYN_WEAK_UNDEF * 16 + WEAK_COMMON: // A weak common symbol is better than an undefined symbol. - to->override(sym, object, version); - return; + return true; case COMMON * 16 + WEAK_COMMON: case WEAK_COMMON * 16 + WEAK_COMMON: @@ -460,7 +493,7 @@ Symbol_table::resolve(Sized_symbol* to, case DYN_WEAK_COMMON * 16 + WEAK_COMMON: // Ignore a weak common symbol in the presence of a real common // symbol. - return; + return false; case DEF * 16 + DYN_COMMON: case WEAK_DEF * 16 + DYN_COMMON: @@ -468,54 +501,114 @@ Symbol_table::resolve(Sized_symbol* to, case DYN_WEAK_DEF * 16 + DYN_COMMON: // Ignore a dynamic common symbol in the presence of a // definition. - return; + return false; case UNDEF * 16 + DYN_COMMON: case WEAK_UNDEF * 16 + DYN_COMMON: case DYN_UNDEF * 16 + DYN_COMMON: case DYN_WEAK_UNDEF * 16 + DYN_COMMON: // A dynamic common symbol is a definition of sorts. - to->override(sym, object, version); - return; + return true; case COMMON * 16 + DYN_COMMON: case WEAK_COMMON * 16 + DYN_COMMON: case DYN_COMMON * 16 + DYN_COMMON: case DYN_WEAK_COMMON * 16 + DYN_COMMON: // Set the size to the maximum. - if (sym.get_st_size() > to->symsize()) - to->set_symsize(sym.get_st_size()); - return; + *adjust_common_sizes = true; + return false; case DEF * 16 + DYN_WEAK_COMMON: case WEAK_DEF * 16 + DYN_WEAK_COMMON: case DYN_DEF * 16 + DYN_WEAK_COMMON: case DYN_WEAK_DEF * 16 + DYN_WEAK_COMMON: // A common symbol is ignored in the face of a definition. - return; + return false; case UNDEF * 16 + DYN_WEAK_COMMON: case WEAK_UNDEF * 16 + DYN_WEAK_COMMON: case DYN_UNDEF * 16 + DYN_WEAK_COMMON: case DYN_WEAK_UNDEF * 16 + DYN_WEAK_COMMON: // I guess a weak common symbol is better than a definition. - to->override(sym, object, version); - return; + return true; case COMMON * 16 + DYN_WEAK_COMMON: case WEAK_COMMON * 16 + DYN_WEAK_COMMON: case DYN_COMMON * 16 + DYN_WEAK_COMMON: case DYN_WEAK_COMMON * 16 + DYN_WEAK_COMMON: // Set the size to the maximum. - if (sym.get_st_size() > to->symsize()) - to->set_symsize(sym.get_st_size()); - return; + *adjust_common_sizes = true; + return false; default: gold_unreachable(); } } +// A special case of should_override which is only called for a strong +// defined symbol from a regular object file. This is used when +// defining special symbols. + +bool +Symbol_table::should_override_with_special(const Symbol* to) +{ + bool adjust_common_sizes; + unsigned int frombits = global_flag | regular_flag | def_flag; + bool ret = Symbol_table::should_override(to, frombits, &adjust_common_sizes); + gold_assert(!adjust_common_sizes); + return ret; +} + +// Override symbol base with a special symbol. + +void +Symbol::override_base_with_special(const Symbol* from) +{ + this->source_ = from->source_; + switch (from->source_) + { + case FROM_OBJECT: + this->u_.from_object = from->u_.from_object; + break; + case IN_OUTPUT_DATA: + this->u_.in_output_data = from->u_.in_output_data; + break; + case IN_OUTPUT_SEGMENT: + this->u_.in_output_segment = from->u_.in_output_segment; + break; + case CONSTANT: + break; + default: + gold_unreachable(); + break; + } + + if (from->version_ != NULL && this->version_ != from->version_) + { + gold_assert(this->version_ == NULL); + this->version_ = from->version_; + } + + this->type_ = from->type_; + this->binding_ = from->binding_; + this->visibility_ = from->visibility_; + this->nonvis_ = from->nonvis_; + + // Special symbols are always considered to be regular symbols. + this->in_reg_ = true; +} + +// Override a symbol with a special symbol. + +template +void +Sized_symbol::override_with_special(const Sized_symbol* from) +{ + this->override_base_with_special(from); + this->value_ = from->value_; + this->symsize_ = from->symsize_; +} + // Instantiate the templates we need. We could use the configure // script to restrict this to only the ones needed for implemented // targets. @@ -560,4 +653,16 @@ Symbol_table::resolve<64, true>( const char* version); #endif +#if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG) +template +void +Sized_symbol<32>::override_with_special(const Sized_symbol<32>*); +#endif + +#if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG) +template +void +Sized_symbol<64>::override_with_special(const Sized_symbol<64>*); +#endif + } // End namespace gold. diff --git a/gold/symtab.cc b/gold/symtab.cc index b7f4aaa4ab..d29f751ad8 100644 --- a/gold/symtab.cc +++ b/gold/symtab.cc @@ -666,28 +666,28 @@ Symbol_table::add_from_dynobj( // Create and return a specially defined symbol. If ONLY_IF_REF is // true, then only create the symbol if there is a reference to it. +// If this does not return NULL, it sets *POLDSYM to the existing +// symbol if there is one. template Sized_symbol* Symbol_table::define_special_symbol(const Target* target, const char* name, - const char* version, bool only_if_ref + const char* version, bool only_if_ref, + Sized_symbol** poldsym ACCEPT_SIZE_ENDIAN) { gold_assert(this->size_ == size); Symbol* oldsym; Sized_symbol* sym; + bool add_to_table = false; + typename Symbol_table_type::iterator add_loc = this->table_.end(); if (only_if_ref) { oldsym = this->lookup(name, version); if (oldsym == NULL || !oldsym->is_undefined()) return NULL; - sym = NULL; - - // Canonicalize NAME and VERSION. - name = oldsym->name(); - version = oldsym->version(); } else { @@ -710,54 +710,39 @@ Symbol_table::define_special_symbol(const Target* target, const char* name, // We already have a symbol table entry for NAME/VERSION. oldsym = ins.first->second; gold_assert(oldsym != NULL); - sym = NULL; } else { // We haven't seen this symbol before. gold_assert(ins.first->second == NULL); - - if (!target->has_make_symbol()) - sym = new Sized_symbol(); - else - { - gold_assert(target->get_size() == size); - gold_assert(target->is_big_endian() ? big_endian : !big_endian); - typedef Sized_target My_target; - const My_target* sized_target = - static_cast(target); - sym = sized_target->make_symbol(); - if (sym == NULL) - return NULL; - } - - ins.first->second = sym; + add_to_table = true; + add_loc = ins.first; oldsym = NULL; } } - if (oldsym != NULL) + if (!target->has_make_symbol()) + sym = new Sized_symbol(); + else { - gold_assert(sym == NULL); - - sym = this->get_sized_symbol SELECT_SIZE_NAME(size) (oldsym - SELECT_SIZE(size)); - gold_assert(sym->source() == Symbol::FROM_OBJECT); - const int old_shndx = sym->shndx(); - if (old_shndx != elfcpp::SHN_UNDEF - && old_shndx != elfcpp::SHN_COMMON - && !sym->object()->is_dynamic()) - { - fprintf(stderr, "%s: linker defined: multiple definition of %s\n", - program_name, name); - // FIXME: Report old location. Record that we have seen an - // error. - return NULL; - } - - // Our new definition is going to override the old reference. + gold_assert(target->get_size() == size); + gold_assert(target->is_big_endian() ? big_endian : !big_endian); + typedef Sized_target My_target; + const My_target* sized_target = + static_cast(target); + sym = sized_target->make_symbol(); + if (sym == NULL) + return NULL; } + if (add_to_table) + add_loc->second = sym; + else + gold_assert(oldsym != NULL); + + *poldsym = this->get_sized_symbol SELECT_SIZE_NAME(size) (oldsym + SELECT_SIZE(size)); + return sym; } @@ -775,15 +760,29 @@ Symbol_table::define_in_output_data(const Target* target, const char* name, { gold_assert(target->get_size() == this->size_); if (this->size_ == 32) - return this->do_define_in_output_data<32>(target, name, version, od, value, - symsize, type, binding, - visibility, nonvis, - offset_is_from_end, only_if_ref); + { +#if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG) + return this->do_define_in_output_data<32>(target, name, version, od, + value, symsize, type, binding, + visibility, nonvis, + offset_is_from_end, + only_if_ref); +#else + gold_unreachable(); +#endif + } else if (this->size_ == 64) - return this->do_define_in_output_data<64>(target, name, version, od, value, - symsize, type, binding, - visibility, nonvis, - offset_is_from_end, only_if_ref); + { +#if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG) + return this->do_define_in_output_data<64>(target, name, version, od, + value, symsize, type, binding, + visibility, nonvis, + offset_is_from_end, + only_if_ref); +#else + gold_unreachable(); +#endif + } else gold_unreachable(); } @@ -807,12 +806,13 @@ Symbol_table::do_define_in_output_data( bool only_if_ref) { Sized_symbol* sym; + Sized_symbol* oldsym; if (target->is_big_endian()) { #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG) sym = this->define_special_symbol SELECT_SIZE_ENDIAN_NAME(size, true) ( - target, name, version, only_if_ref + target, name, version, only_if_ref, &oldsym SELECT_SIZE_ENDIAN(size, true)); #else gold_unreachable(); @@ -822,7 +822,7 @@ Symbol_table::do_define_in_output_data( { #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE) sym = this->define_special_symbol SELECT_SIZE_ENDIAN_NAME(size, false) ( - target, name, version, only_if_ref + target, name, version, only_if_ref, &oldsym SELECT_SIZE_ENDIAN(size, false)); #else gold_unreachable(); @@ -835,6 +835,10 @@ Symbol_table::do_define_in_output_data( sym->init(name, od, value, symsize, type, binding, visibility, nonvis, offset_is_from_end); + if (oldsym != NULL + && Symbol_table::should_override_with_special(oldsym)) + oldsym->override_with_special(sym); + return sym; } @@ -852,15 +856,27 @@ Symbol_table::define_in_output_segment(const Target* target, const char* name, { gold_assert(target->get_size() == this->size_); if (this->size_ == 32) - return this->do_define_in_output_segment<32>(target, name, version, os, - value, symsize, type, binding, - visibility, nonvis, - offset_base, only_if_ref); + { +#if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG) + return this->do_define_in_output_segment<32>(target, name, version, os, + value, symsize, type, + binding, visibility, nonvis, + offset_base, only_if_ref); +#else + gold_unreachable(); +#endif + } else if (this->size_ == 64) - return this->do_define_in_output_segment<64>(target, name, version, os, - value, symsize, type, binding, - visibility, nonvis, - offset_base, only_if_ref); + { +#if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG) + return this->do_define_in_output_segment<64>(target, name, version, os, + value, symsize, type, + binding, visibility, nonvis, + offset_base, only_if_ref); +#else + gold_unreachable(); +#endif + } else gold_unreachable(); } @@ -884,14 +900,15 @@ Symbol_table::do_define_in_output_segment( bool only_if_ref) { Sized_symbol* sym; + Sized_symbol* oldsym; if (target->is_big_endian()) sym = this->define_special_symbol SELECT_SIZE_ENDIAN_NAME(size, true) ( - target, name, version, only_if_ref + target, name, version, only_if_ref, &oldsym SELECT_SIZE_ENDIAN(size, true)); else sym = this->define_special_symbol SELECT_SIZE_ENDIAN_NAME(size, false) ( - target, name, version, only_if_ref + target, name, version, only_if_ref, &oldsym SELECT_SIZE_ENDIAN(size, false)); if (sym == NULL) @@ -900,6 +917,10 @@ Symbol_table::do_define_in_output_segment( sym->init(name, os, value, symsize, type, binding, visibility, nonvis, offset_base); + if (oldsym != NULL + && Symbol_table::should_override_with_special(oldsym)) + oldsym->override_with_special(sym); + return sym; } @@ -915,13 +936,25 @@ Symbol_table::define_as_constant(const Target* target, const char* name, { gold_assert(target->get_size() == this->size_); if (this->size_ == 32) - return this->do_define_as_constant<32>(target, name, version, value, - symsize, type, binding, visibility, - nonvis, only_if_ref); + { +#if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG) + return this->do_define_as_constant<32>(target, name, version, value, + symsize, type, binding, + visibility, nonvis, only_if_ref); +#else + gold_unreachable(); +#endif + } else if (this->size_ == 64) - return this->do_define_as_constant<64>(target, name, version, value, - symsize, type, binding, visibility, - nonvis, only_if_ref); + { +#if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG) + return this->do_define_as_constant<64>(target, name, version, value, + symsize, type, binding, + visibility, nonvis, only_if_ref); +#else + gold_unreachable(); +#endif + } else gold_unreachable(); } @@ -943,14 +976,15 @@ Symbol_table::do_define_as_constant( bool only_if_ref) { Sized_symbol* sym; + Sized_symbol* oldsym; if (target->is_big_endian()) sym = this->define_special_symbol SELECT_SIZE_ENDIAN_NAME(size, true) ( - target, name, version, only_if_ref + target, name, version, only_if_ref, &oldsym SELECT_SIZE_ENDIAN(size, true)); else sym = this->define_special_symbol SELECT_SIZE_ENDIAN_NAME(size, false) ( - target, name, version, only_if_ref + target, name, version, only_if_ref, &oldsym SELECT_SIZE_ENDIAN(size, false)); if (sym == NULL) @@ -958,6 +992,10 @@ Symbol_table::do_define_as_constant( sym->init(name, value, symsize, type, binding, visibility, nonvis); + if (oldsym != NULL + && Symbol_table::should_override_with_special(oldsym)) + oldsym->override_with_special(sym); + return sym; } diff --git a/gold/symtab.h b/gold/symtab.h index 816afb3884..534ee0d9fa 100644 --- a/gold/symtab.h +++ b/gold/symtab.h @@ -404,6 +404,10 @@ class Symbol override_base(const elfcpp::Sym&, Object* object, const char* version); + // Override existing symbol with a special symbol. + void + override_base_with_special(const Symbol* from); + private: Symbol(const Symbol&); Symbol& operator=(const Symbol&); @@ -549,6 +553,10 @@ class Sized_symbol : public Symbol override(const elfcpp::Sym&, Object* object, const char* version); + // Override existing symbol with a special symbol. + void + override_with_special(const Sized_symbol*); + // Return the symbol's value. Value_type value() const @@ -905,12 +913,22 @@ class Symbol_table resolve(Sized_symbol* to, const Sized_symbol* from, const char* version ACCEPT_SIZE_ENDIAN); + // Whether we should override a symbol, based on flags in + // resolve.cc. + static bool + should_override(const Symbol*, unsigned int, bool*); + + // Whether we should override a symbol with a special symbol which + // is automatically defined by the linker. + static bool + should_override_with_special(const Symbol*); + // Define a special symbol. template Sized_symbol* define_special_symbol(const Target* target, const char* name, - const char* version, bool only_if_ref - ACCEPT_SIZE_ENDIAN); + const char* version, bool only_if_ref, + Sized_symbol** poldsym ACCEPT_SIZE_ENDIAN); // Define a symbol in an Output_data, sized version. template