X-Git-Url: https://oss.titaniummirror.com/gitweb?p=msp430-binutils.git;a=blobdiff_plain;f=gold%2Fcommon.cc;fp=gold%2Fcommon.cc;h=f90ae40e1b56d826819629d6f84d163210fce20e;hp=0000000000000000000000000000000000000000;hb=88750007d7869f178f0ba528f41efd3b74c424cf;hpb=6df9443a374e2b81278c61b8afc0a1eef7db280b diff --git a/gold/common.cc b/gold/common.cc new file mode 100644 index 0000000..f90ae40 --- /dev/null +++ b/gold/common.cc @@ -0,0 +1,279 @@ +// common.cc -- handle common symbols for gold + +// Copyright 2006, 2007, 2008 Free Software Foundation, Inc. +// Written by Ian Lance Taylor . + +// 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. + +#include "gold.h" + +#include + +#include "workqueue.h" +#include "mapfile.h" +#include "layout.h" +#include "output.h" +#include "symtab.h" +#include "common.h" + +namespace gold +{ + +// Allocate_commons_task methods. + +// This task allocates the common symbols. We need a lock on the +// symbol table. + +Task_token* +Allocate_commons_task::is_runnable() +{ + if (!this->symtab_lock_->is_writable()) + return this->symtab_lock_; + return NULL; +} + +// Return the locks we hold: one on the symbol table, and one blocker. + +void +Allocate_commons_task::locks(Task_locker* tl) +{ + tl->add(this, this->blocker_); + tl->add(this, this->symtab_lock_); +} + +// Allocate the common symbols. + +void +Allocate_commons_task::run(Workqueue*) +{ + this->symtab_->allocate_commons(this->layout_, this->mapfile_); +} + +// This class is used to sort the common symbol by size. We put the +// larger common symbols first. + +template +class Sort_commons +{ + public: + Sort_commons(const Symbol_table* symtab) + : symtab_(symtab) + { } + + bool operator()(const Symbol* a, const Symbol* b) const; + + private: + const Symbol_table* symtab_; +}; + +template +bool +Sort_commons::operator()(const Symbol* pa, const Symbol* pb) const +{ + if (pa == NULL) + return false; + if (pb == NULL) + return true; + + const Symbol_table* symtab = this->symtab_; + const Sized_symbol* psa = symtab->get_sized_symbol(pa); + const Sized_symbol* psb = symtab->get_sized_symbol(pb); + + // Sort by largest size first. + typename Sized_symbol::Size_type sa = psa->symsize(); + typename Sized_symbol::Size_type sb = psb->symsize(); + if (sa < sb) + return false; + else if (sb < sa) + return true; + + // When the symbols are the same size, we sort them by alignment, + // largest alignment first. + typename Sized_symbol::Value_type va = psa->value(); + typename Sized_symbol::Value_type vb = psb->value(); + if (va < vb) + return false; + else if (vb < va) + return true; + + // Otherwise we stabilize the sort by sorting by name. + return strcmp(psa->name(), psb->name()) < 0; +} + +// Allocate the common symbols. + +void +Symbol_table::allocate_commons(Layout* layout, Mapfile* mapfile) +{ + if (parameters->target().get_size() == 32) + { +#if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG) + this->do_allocate_commons<32>(layout, mapfile); +#else + gold_unreachable(); +#endif + } + else if (parameters->target().get_size() == 64) + { +#if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG) + this->do_allocate_commons<64>(layout, mapfile); +#else + gold_unreachable(); +#endif + } + else + gold_unreachable(); +} + +// Allocated the common symbols, sized version. + +template +void +Symbol_table::do_allocate_commons(Layout* layout, Mapfile* mapfile) +{ + if (!this->commons_.empty()) + this->do_allocate_commons_list(layout, COMMONS_NORMAL, + &this->commons_, mapfile); + if (!this->tls_commons_.empty()) + this->do_allocate_commons_list(layout, COMMONS_TLS, + &this->tls_commons_, mapfile); + if (!this->small_commons_.empty()) + this->do_allocate_commons_list(layout, COMMONS_SMALL, + &this->small_commons_, mapfile); + if (!this->large_commons_.empty()) + this->do_allocate_commons_list(layout, COMMONS_LARGE, + &this->large_commons_, mapfile); +} + +// Allocate the common symbols in a list. IS_TLS indicates whether +// these are TLS common symbols. + +template +void +Symbol_table::do_allocate_commons_list( + Layout* layout, + Commons_section_type commons_section_type, + Commons_type* commons, + Mapfile* mapfile) +{ + typedef typename Sized_symbol::Value_type Value_type; + typedef typename Sized_symbol::Size_type Size_type; + + // We've kept a list of all the common symbols. But the symbol may + // have been resolved to a defined symbol by now. And it may be a + // forwarder. First remove all non-common symbols. + bool any = false; + uint64_t addralign = 0; + for (Commons_type::iterator p = commons->begin(); + p != commons->end(); + ++p) + { + Symbol* sym = *p; + if (sym->is_forwarder()) + { + sym = this->resolve_forwards(sym); + *p = sym; + } + if (!sym->is_common()) + *p = NULL; + else + { + any = true; + Sized_symbol* ssym = this->get_sized_symbol(sym); + if (ssym->value() > addralign) + addralign = ssym->value(); + } + } + if (!any) + return; + + // Sort the common symbols by size, so that they pack better into + // memory. + std::sort(commons->begin(), commons->end(), + Sort_commons(this)); + + // Place them in a newly allocated BSS section. + elfcpp::Elf_Xword flags = elfcpp::SHF_WRITE | elfcpp::SHF_ALLOC; + const char* name; + const char* ds_name; + switch (commons_section_type) + { + case COMMONS_NORMAL: + name = ".bss"; + ds_name = "** common"; + break; + case COMMONS_TLS: + flags |= elfcpp::SHF_TLS; + name = ".tbss"; + ds_name = "** tls common"; + break; + case COMMONS_SMALL: + flags |= parameters->target().small_common_section_flags(); + name = ".sbss"; + ds_name = "** small common"; + break; + case COMMONS_LARGE: + flags |= parameters->target().large_common_section_flags(); + name = ".lbss"; + ds_name = "** large common"; + break; + default: + gold_unreachable(); + } + + Output_data_space *poc = new Output_data_space(addralign, ds_name); + Output_section *os = layout->add_output_section_data(name, + elfcpp::SHT_NOBITS, + flags, poc); + if (os != NULL) + { + if (commons_section_type == COMMONS_SMALL) + os->set_is_small_section(); + else if (commons_section_type == COMMONS_LARGE) + os->set_is_large_section(); + } + + // Allocate them all. + + off_t off = 0; + for (Commons_type::iterator p = commons->begin(); + p != commons->end(); + ++p) + { + Symbol* sym = *p; + if (sym == NULL) + break; + Sized_symbol* ssym = this->get_sized_symbol(sym); + + // Record the symbol in the map file now, before we change its + // value. Pass the size in separately so that we don't have to + // templatize the map code, which is not performance sensitive. + if (mapfile != NULL) + mapfile->report_allocate_common(sym, ssym->symsize()); + + off = align_address(off, ssym->value()); + ssym->allocate_common(poc, off); + off += ssym->symsize(); + } + + poc->set_current_data_size(off); + + commons->clear(); +} + +} // End namespace gold.