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- // script-sections.cc -- linker script SECTIONS for gold
- // Copyright (C) 2008-2022 Free Software Foundation, Inc.
- // Written by Ian Lance Taylor <iant@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.
- #include "gold.h"
- #include <cstring>
- #include <algorithm>
- #include <list>
- #include <map>
- #include <string>
- #include <vector>
- #include <fnmatch.h>
- #include "parameters.h"
- #include "object.h"
- #include "layout.h"
- #include "output.h"
- #include "script-c.h"
- #include "script.h"
- #include "script-sections.h"
- // Support for the SECTIONS clause in linker scripts.
- namespace gold
- {
- // A region of memory.
- class Memory_region
- {
- public:
- Memory_region(const char* name, size_t namelen, unsigned int attributes,
- Expression* start, Expression* length)
- : name_(name, namelen),
- attributes_(attributes),
- start_(start),
- length_(length),
- current_offset_(0),
- vma_sections_(),
- lma_sections_(),
- last_section_(NULL)
- { }
- // Return the name of this region.
- const std::string&
- name() const
- { return this->name_; }
- // Return the start address of this region.
- Expression*
- start_address() const
- { return this->start_; }
- // Return the length of this region.
- Expression*
- length() const
- { return this->length_; }
- // Print the region (when debugging).
- void
- print(FILE*) const;
- // Return true if <name,namelen> matches this region.
- bool
- name_match(const char* name, size_t namelen)
- {
- return (this->name_.length() == namelen
- && strncmp(this->name_.c_str(), name, namelen) == 0);
- }
- Expression*
- get_current_address() const
- {
- return
- script_exp_binary_add(this->start_,
- script_exp_integer(this->current_offset_));
- }
- void
- set_address(uint64_t addr, const Symbol_table* symtab, const Layout* layout)
- {
- uint64_t start = this->start_->eval(symtab, layout, false);
- uint64_t len = this->length_->eval(symtab, layout, false);
- if (addr < start || addr >= start + len)
- gold_error(_("address 0x%llx is not within region %s"),
- static_cast<unsigned long long>(addr),
- this->name_.c_str());
- else if (addr < start + this->current_offset_)
- gold_error(_("address 0x%llx moves dot backwards in region %s"),
- static_cast<unsigned long long>(addr),
- this->name_.c_str());
- this->current_offset_ = addr - start;
- }
- void
- increment_offset(std::string section_name, uint64_t amount,
- const Symbol_table* symtab, const Layout* layout)
- {
- this->current_offset_ += amount;
- if (this->current_offset_
- > this->length_->eval(symtab, layout, false))
- gold_error(_("section %s overflows end of region %s"),
- section_name.c_str(), this->name_.c_str());
- }
- // Returns true iff there is room left in this region
- // for AMOUNT more bytes of data.
- bool
- has_room_for(const Symbol_table* symtab, const Layout* layout,
- uint64_t amount) const
- {
- return (this->current_offset_ + amount
- < this->length_->eval(symtab, layout, false));
- }
- // Return true if the provided section flags
- // are compatible with this region's attributes.
- bool
- attributes_compatible(elfcpp::Elf_Xword flags, elfcpp::Elf_Xword type) const;
- void
- add_section(Output_section_definition* sec, bool vma)
- {
- if (vma)
- this->vma_sections_.push_back(sec);
- else
- this->lma_sections_.push_back(sec);
- }
- typedef std::vector<Output_section_definition*> Section_list;
- // Return the start of the list of sections
- // whose VMAs are taken from this region.
- Section_list::const_iterator
- get_vma_section_list_start() const
- { return this->vma_sections_.begin(); }
- // Return the start of the list of sections
- // whose LMAs are taken from this region.
- Section_list::const_iterator
- get_lma_section_list_start() const
- { return this->lma_sections_.begin(); }
- // Return the end of the list of sections
- // whose VMAs are taken from this region.
- Section_list::const_iterator
- get_vma_section_list_end() const
- { return this->vma_sections_.end(); }
- // Return the end of the list of sections
- // whose LMAs are taken from this region.
- Section_list::const_iterator
- get_lma_section_list_end() const
- { return this->lma_sections_.end(); }
- Output_section_definition*
- get_last_section() const
- { return this->last_section_; }
- void
- set_last_section(Output_section_definition* sec)
- { this->last_section_ = sec; }
- private:
- std::string name_;
- unsigned int attributes_;
- Expression* start_;
- Expression* length_;
- // The offset to the next free byte in the region.
- // Note - for compatibility with GNU LD we only maintain one offset
- // regardless of whether the region is being used for VMA values,
- // LMA values, or both.
- uint64_t current_offset_;
- // A list of sections whose VMAs are set inside this region.
- Section_list vma_sections_;
- // A list of sections whose LMAs are set inside this region.
- Section_list lma_sections_;
- // The latest section to make use of this region.
- Output_section_definition* last_section_;
- };
- // Return true if the provided section flags
- // are compatible with this region's attributes.
- bool
- Memory_region::attributes_compatible(elfcpp::Elf_Xword flags,
- elfcpp::Elf_Xword type) const
- {
- unsigned int attrs = this->attributes_;
- // No attributes means that this region is not compatible with anything.
- if (attrs == 0)
- return false;
- bool match = true;
- do
- {
- switch (attrs & - attrs)
- {
- case MEM_EXECUTABLE:
- if ((flags & elfcpp::SHF_EXECINSTR) == 0)
- match = false;
- break;
- case MEM_WRITEABLE:
- if ((flags & elfcpp::SHF_WRITE) == 0)
- match = false;
- break;
- case MEM_READABLE:
- // All sections are presumed readable.
- break;
- case MEM_ALLOCATABLE:
- if ((flags & elfcpp::SHF_ALLOC) == 0)
- match = false;
- break;
- case MEM_INITIALIZED:
- if ((type & elfcpp::SHT_NOBITS) != 0)
- match = false;
- break;
- }
- attrs &= ~ (attrs & - attrs);
- }
- while (attrs != 0);
- return match;
- }
- // Print a memory region.
- void
- Memory_region::print(FILE* f) const
- {
- fprintf(f, " %s", this->name_.c_str());
- unsigned int attrs = this->attributes_;
- if (attrs != 0)
- {
- fprintf(f, " (");
- do
- {
- switch (attrs & - attrs)
- {
- case MEM_EXECUTABLE: fputc('x', f); break;
- case MEM_WRITEABLE: fputc('w', f); break;
- case MEM_READABLE: fputc('r', f); break;
- case MEM_ALLOCATABLE: fputc('a', f); break;
- case MEM_INITIALIZED: fputc('i', f); break;
- default:
- gold_unreachable();
- }
- attrs &= ~ (attrs & - attrs);
- }
- while (attrs != 0);
- fputc(')', f);
- }
- fprintf(f, " : origin = ");
- this->start_->print(f);
- fprintf(f, ", length = ");
- this->length_->print(f);
- fprintf(f, "\n");
- }
- // Manage orphan sections. This is intended to be largely compatible
- // with the GNU linker. The Linux kernel implicitly relies on
- // something similar to the GNU linker's orphan placement. We
- // originally used a simpler scheme here, but it caused the kernel
- // build to fail, and was also rather inefficient.
- class Orphan_section_placement
- {
- private:
- typedef Script_sections::Elements_iterator Elements_iterator;
- public:
- Orphan_section_placement();
- // Handle an output section during initialization of this mapping.
- void
- output_section_init(const std::string& name, Output_section*,
- Elements_iterator location);
- // Initialize the last location.
- void
- last_init(Elements_iterator location);
- // Set *PWHERE to the address of an iterator pointing to the
- // location to use for an orphan section. Return true if the
- // iterator has a value, false otherwise.
- bool
- find_place(Output_section*, Elements_iterator** pwhere);
- // Update PLACE_LAST_ALLOC.
- void
- update_last_alloc(Elements_iterator where);
- // Return the iterator being used for sections at the very end of
- // the linker script.
- Elements_iterator
- last_place() const;
- private:
- // The places that we specifically recognize. This list is copied
- // from the GNU linker.
- enum Place_index
- {
- PLACE_TEXT,
- PLACE_RODATA,
- PLACE_DATA,
- PLACE_TLS,
- PLACE_TLS_BSS,
- PLACE_BSS,
- PLACE_LAST_ALLOC,
- PLACE_REL,
- PLACE_INTERP,
- PLACE_NONALLOC,
- PLACE_LAST,
- PLACE_MAX
- };
- // The information we keep for a specific place.
- struct Place
- {
- // The name of sections for this place.
- const char* name;
- // Whether we have a location for this place.
- bool have_location;
- // The iterator for this place.
- Elements_iterator location;
- };
- // Initialize one place element.
- void
- initialize_place(Place_index, const char*);
- // The places.
- Place places_[PLACE_MAX];
- // True if this is the first call to output_section_init.
- bool first_init_;
- };
- // Initialize Orphan_section_placement.
- Orphan_section_placement::Orphan_section_placement()
- : first_init_(true)
- {
- this->initialize_place(PLACE_TEXT, ".text");
- this->initialize_place(PLACE_RODATA, ".rodata");
- this->initialize_place(PLACE_DATA, ".data");
- this->initialize_place(PLACE_TLS, NULL);
- this->initialize_place(PLACE_TLS_BSS, NULL);
- this->initialize_place(PLACE_BSS, ".bss");
- this->initialize_place(PLACE_LAST_ALLOC, NULL);
- this->initialize_place(PLACE_REL, NULL);
- this->initialize_place(PLACE_INTERP, ".interp");
- this->initialize_place(PLACE_NONALLOC, NULL);
- this->initialize_place(PLACE_LAST, NULL);
- }
- // Initialize one place element.
- void
- Orphan_section_placement::initialize_place(Place_index index, const char* name)
- {
- this->places_[index].name = name;
- this->places_[index].have_location = false;
- }
- // While initializing the Orphan_section_placement information, this
- // is called once for each output section named in the linker script.
- // If we found an output section during the link, it will be passed in
- // OS.
- void
- Orphan_section_placement::output_section_init(const std::string& name,
- Output_section* os,
- Elements_iterator location)
- {
- bool first_init = this->first_init_;
- this->first_init_ = false;
- // Remember the last allocated section. Any orphan bss sections
- // will be placed after it.
- if (os != NULL
- && (os->flags() & elfcpp::SHF_ALLOC) != 0)
- {
- this->places_[PLACE_LAST_ALLOC].location = location;
- this->places_[PLACE_LAST_ALLOC].have_location = true;
- }
- for (int i = 0; i < PLACE_MAX; ++i)
- {
- if (this->places_[i].name != NULL && this->places_[i].name == name)
- {
- if (this->places_[i].have_location)
- {
- // We have already seen a section with this name.
- return;
- }
- this->places_[i].location = location;
- this->places_[i].have_location = true;
- // If we just found the .bss section, restart the search for
- // an unallocated section. This follows the GNU linker's
- // behaviour.
- if (i == PLACE_BSS)
- this->places_[PLACE_NONALLOC].have_location = false;
- return;
- }
- }
- // Relocation sections.
- if (!this->places_[PLACE_REL].have_location
- && os != NULL
- && (os->type() == elfcpp::SHT_REL || os->type() == elfcpp::SHT_RELA)
- && (os->flags() & elfcpp::SHF_ALLOC) != 0)
- {
- this->places_[PLACE_REL].location = location;
- this->places_[PLACE_REL].have_location = true;
- }
- // We find the location for unallocated sections by finding the
- // first debugging or comment section after the BSS section (if
- // there is one).
- if (!this->places_[PLACE_NONALLOC].have_location
- && (name == ".comment" || Layout::is_debug_info_section(name.c_str())))
- {
- // We add orphan sections after the location in PLACES_. We
- // want to store unallocated sections before LOCATION. If this
- // is the very first section, we can't use it.
- if (!first_init)
- {
- --location;
- this->places_[PLACE_NONALLOC].location = location;
- this->places_[PLACE_NONALLOC].have_location = true;
- }
- }
- }
- // Initialize the last location.
- void
- Orphan_section_placement::last_init(Elements_iterator location)
- {
- this->places_[PLACE_LAST].location = location;
- this->places_[PLACE_LAST].have_location = true;
- }
- // Set *PWHERE to the address of an iterator pointing to the location
- // to use for an orphan section. Return true if the iterator has a
- // value, false otherwise.
- bool
- Orphan_section_placement::find_place(Output_section* os,
- Elements_iterator** pwhere)
- {
- // Figure out where OS should go. This is based on the GNU linker
- // code. FIXME: The GNU linker handles small data sections
- // specially, but we don't.
- elfcpp::Elf_Word type = os->type();
- elfcpp::Elf_Xword flags = os->flags();
- Place_index index;
- if ((flags & elfcpp::SHF_ALLOC) == 0
- && !Layout::is_debug_info_section(os->name()))
- index = PLACE_NONALLOC;
- else if ((flags & elfcpp::SHF_ALLOC) == 0)
- index = PLACE_LAST;
- else if (type == elfcpp::SHT_NOTE)
- index = PLACE_INTERP;
- else if ((flags & elfcpp::SHF_TLS) != 0)
- {
- if (type == elfcpp::SHT_NOBITS)
- index = PLACE_TLS_BSS;
- else
- index = PLACE_TLS;
- }
- else if (type == elfcpp::SHT_NOBITS)
- index = PLACE_BSS;
- else if ((flags & elfcpp::SHF_WRITE) != 0)
- index = PLACE_DATA;
- else if (type == elfcpp::SHT_REL || type == elfcpp::SHT_RELA)
- index = PLACE_REL;
- else if ((flags & elfcpp::SHF_EXECINSTR) == 0)
- index = PLACE_RODATA;
- else
- index = PLACE_TEXT;
- // If we don't have a location yet, try to find one based on a
- // plausible ordering of sections.
- if (!this->places_[index].have_location)
- {
- Place_index follow;
- switch (index)
- {
- default:
- follow = PLACE_MAX;
- break;
- case PLACE_RODATA:
- follow = PLACE_TEXT;
- break;
- case PLACE_DATA:
- follow = PLACE_RODATA;
- if (!this->places_[PLACE_RODATA].have_location)
- follow = PLACE_TEXT;
- break;
- case PLACE_BSS:
- follow = PLACE_LAST_ALLOC;
- break;
- case PLACE_REL:
- follow = PLACE_TEXT;
- break;
- case PLACE_INTERP:
- follow = PLACE_TEXT;
- break;
- case PLACE_TLS:
- follow = PLACE_DATA;
- break;
- case PLACE_TLS_BSS:
- follow = PLACE_TLS;
- if (!this->places_[PLACE_TLS].have_location)
- follow = PLACE_DATA;
- break;
- }
- if (follow != PLACE_MAX && this->places_[follow].have_location)
- {
- // Set the location of INDEX to the location of FOLLOW. The
- // location of INDEX will then be incremented by the caller,
- // so anything in INDEX will continue to be after anything
- // in FOLLOW.
- this->places_[index].location = this->places_[follow].location;
- this->places_[index].have_location = true;
- }
- }
- *pwhere = &this->places_[index].location;
- bool ret = this->places_[index].have_location;
- // The caller will set the location.
- this->places_[index].have_location = true;
- return ret;
- }
- // Update PLACE_LAST_ALLOC.
- void
- Orphan_section_placement::update_last_alloc(Elements_iterator elem)
- {
- Elements_iterator prev = elem;
- --prev;
- if (this->places_[PLACE_LAST_ALLOC].have_location
- && this->places_[PLACE_LAST_ALLOC].location == prev)
- {
- this->places_[PLACE_LAST_ALLOC].have_location = true;
- this->places_[PLACE_LAST_ALLOC].location = elem;
- }
- }
- // Return the iterator being used for sections at the very end of the
- // linker script.
- Orphan_section_placement::Elements_iterator
- Orphan_section_placement::last_place() const
- {
- gold_assert(this->places_[PLACE_LAST].have_location);
- return this->places_[PLACE_LAST].location;
- }
- // An element in a SECTIONS clause.
- class Sections_element
- {
- public:
- Sections_element()
- { }
- virtual ~Sections_element()
- { }
- // Return whether an output section is relro.
- virtual bool
- is_relro() const
- { return false; }
- // Record that an output section is relro.
- virtual void
- set_is_relro()
- { }
- // Create any required output sections. The only real
- // implementation is in Output_section_definition.
- virtual void
- create_sections(Layout*)
- { }
- // Add any symbol being defined to the symbol table.
- virtual void
- add_symbols_to_table(Symbol_table*)
- { }
- // Finalize symbols and check assertions.
- virtual void
- finalize_symbols(Symbol_table*, const Layout*, uint64_t*)
- { }
- // Return the output section name to use for an input file name and
- // section name. This only real implementation is in
- // Output_section_definition.
- virtual const char*
- output_section_name(const char*, const char*, Output_section***,
- Script_sections::Section_type*, bool*, bool)
- { return NULL; }
- // Initialize OSP with an output section.
- virtual void
- orphan_section_init(Orphan_section_placement*,
- Script_sections::Elements_iterator)
- { }
- // Set section addresses. This includes applying assignments if the
- // expression is an absolute value.
- virtual void
- set_section_addresses(Symbol_table*, Layout*, uint64_t*, uint64_t*,
- uint64_t*)
- { }
- // Check a constraint (ONLY_IF_RO, etc.) on an output section. If
- // this section is constrained, and the input sections do not match,
- // return the constraint, and set *POSD.
- virtual Section_constraint
- check_constraint(Output_section_definition**)
- { return CONSTRAINT_NONE; }
- // See if this is the alternate output section for a constrained
- // output section. If it is, transfer the Output_section and return
- // true. Otherwise return false.
- virtual bool
- alternate_constraint(Output_section_definition*, Section_constraint)
- { return false; }
- // Get the list of segments to use for an allocated section when
- // using a PHDRS clause. If this is an allocated section, return
- // the Output_section, and set *PHDRS_LIST (the first parameter) to
- // the list of PHDRS to which it should be attached. If the PHDRS
- // were not specified, don't change *PHDRS_LIST. When not returning
- // NULL, set *ORPHAN (the second parameter) according to whether
- // this is an orphan section--one that is not mentioned in the
- // linker script.
- virtual Output_section*
- allocate_to_segment(String_list**, bool*)
- { return NULL; }
- // Look for an output section by name and return the address, the
- // load address, the alignment, and the size. This is used when an
- // expression refers to an output section which was not actually
- // created. This returns true if the section was found, false
- // otherwise. The only real definition is for
- // Output_section_definition.
- virtual bool
- get_output_section_info(const char*, uint64_t*, uint64_t*, uint64_t*,
- uint64_t*) const
- { return false; }
- // Return the associated Output_section if there is one.
- virtual Output_section*
- get_output_section() const
- { return NULL; }
- // Set the section's memory regions.
- virtual void
- set_memory_region(Memory_region*, bool)
- { gold_error(_("Attempt to set a memory region for a non-output section")); }
- // Print the element for debugging purposes.
- virtual void
- print(FILE* f) const = 0;
- };
- // An assignment in a SECTIONS clause outside of an output section.
- class Sections_element_assignment : public Sections_element
- {
- public:
- Sections_element_assignment(const char* name, size_t namelen,
- Expression* val, bool provide, bool hidden)
- : assignment_(name, namelen, false, val, provide, hidden)
- { }
- // Add the symbol to the symbol table.
- void
- add_symbols_to_table(Symbol_table* symtab)
- { this->assignment_.add_to_table(symtab); }
- // Finalize the symbol.
- void
- finalize_symbols(Symbol_table* symtab, const Layout* layout,
- uint64_t* dot_value)
- {
- this->assignment_.finalize_with_dot(symtab, layout, *dot_value, NULL);
- }
- // Set the section address. There is no section here, but if the
- // value is absolute, we set the symbol. This permits us to use
- // absolute symbols when setting dot.
- void
- set_section_addresses(Symbol_table* symtab, Layout* layout,
- uint64_t* dot_value, uint64_t*, uint64_t*)
- {
- this->assignment_.set_if_absolute(symtab, layout, true, *dot_value, NULL);
- }
- // Print for debugging.
- void
- print(FILE* f) const
- {
- fprintf(f, " ");
- this->assignment_.print(f);
- }
- private:
- Symbol_assignment assignment_;
- };
- // An assignment to the dot symbol in a SECTIONS clause outside of an
- // output section.
- class Sections_element_dot_assignment : public Sections_element
- {
- public:
- Sections_element_dot_assignment(Expression* val)
- : val_(val)
- { }
- // Finalize the symbol.
- void
- finalize_symbols(Symbol_table* symtab, const Layout* layout,
- uint64_t* dot_value)
- {
- // We ignore the section of the result because outside of an
- // output section definition the dot symbol is always considered
- // to be absolute.
- *dot_value = this->val_->eval_with_dot(symtab, layout, true, *dot_value,
- NULL, NULL, NULL, false);
- }
- // Update the dot symbol while setting section addresses.
- void
- set_section_addresses(Symbol_table* symtab, Layout* layout,
- uint64_t* dot_value, uint64_t* dot_alignment,
- uint64_t* load_address)
- {
- *dot_value = this->val_->eval_with_dot(symtab, layout, false, *dot_value,
- NULL, NULL, dot_alignment, false);
- *load_address = *dot_value;
- }
- // Print for debugging.
- void
- print(FILE* f) const
- {
- fprintf(f, " . = ");
- this->val_->print(f);
- fprintf(f, "\n");
- }
- private:
- Expression* val_;
- };
- // An assertion in a SECTIONS clause outside of an output section.
- class Sections_element_assertion : public Sections_element
- {
- public:
- Sections_element_assertion(Expression* check, const char* message,
- size_t messagelen)
- : assertion_(check, message, messagelen)
- { }
- // Check the assertion.
- void
- finalize_symbols(Symbol_table* symtab, const Layout* layout, uint64_t*)
- { this->assertion_.check(symtab, layout); }
- // Print for debugging.
- void
- print(FILE* f) const
- {
- fprintf(f, " ");
- this->assertion_.print(f);
- }
- private:
- Script_assertion assertion_;
- };
- // An element in an output section in a SECTIONS clause.
- class Output_section_element
- {
- public:
- // A list of input sections.
- typedef std::list<Output_section::Input_section> Input_section_list;
- Output_section_element()
- { }
- virtual ~Output_section_element()
- { }
- // Return whether this element requires an output section to exist.
- virtual bool
- needs_output_section() const
- { return false; }
- // Add any symbol being defined to the symbol table.
- virtual void
- add_symbols_to_table(Symbol_table*)
- { }
- // Finalize symbols and check assertions.
- virtual void
- finalize_symbols(Symbol_table*, const Layout*, uint64_t*, Output_section**)
- { }
- // Return whether this element matches FILE_NAME and SECTION_NAME.
- // The only real implementation is in Output_section_element_input.
- virtual bool
- match_name(const char*, const char*, bool *) const
- { return false; }
- // Set section addresses. This includes applying assignments if the
- // expression is an absolute value.
- virtual void
- set_section_addresses(Symbol_table*, Layout*, Output_section*, uint64_t,
- uint64_t*, uint64_t*, Output_section**, std::string*,
- Input_section_list*)
- { }
- // Print the element for debugging purposes.
- virtual void
- print(FILE* f) const = 0;
- protected:
- // Return a fill string that is LENGTH bytes long, filling it with
- // FILL.
- std::string
- get_fill_string(const std::string* fill, section_size_type length) const;
- };
- std::string
- Output_section_element::get_fill_string(const std::string* fill,
- section_size_type length) const
- {
- std::string this_fill;
- this_fill.reserve(length);
- while (this_fill.length() + fill->length() <= length)
- this_fill += *fill;
- if (this_fill.length() < length)
- this_fill.append(*fill, 0, length - this_fill.length());
- return this_fill;
- }
- // A symbol assignment in an output section.
- class Output_section_element_assignment : public Output_section_element
- {
- public:
- Output_section_element_assignment(const char* name, size_t namelen,
- Expression* val, bool provide,
- bool hidden)
- : assignment_(name, namelen, false, val, provide, hidden)
- { }
- // Add the symbol to the symbol table.
- void
- add_symbols_to_table(Symbol_table* symtab)
- { this->assignment_.add_to_table(symtab); }
- // Finalize the symbol.
- void
- finalize_symbols(Symbol_table* symtab, const Layout* layout,
- uint64_t* dot_value, Output_section** dot_section)
- {
- this->assignment_.finalize_with_dot(symtab, layout, *dot_value,
- *dot_section);
- }
- // Set the section address. There is no section here, but if the
- // value is absolute, we set the symbol. This permits us to use
- // absolute symbols when setting dot.
- void
- set_section_addresses(Symbol_table* symtab, Layout* layout, Output_section*,
- uint64_t, uint64_t* dot_value, uint64_t*,
- Output_section** dot_section, std::string*,
- Input_section_list*)
- {
- this->assignment_.set_if_absolute(symtab, layout, true, *dot_value,
- *dot_section);
- }
- // Print for debugging.
- void
- print(FILE* f) const
- {
- fprintf(f, " ");
- this->assignment_.print(f);
- }
- private:
- Symbol_assignment assignment_;
- };
- // An assignment to the dot symbol in an output section.
- class Output_section_element_dot_assignment : public Output_section_element
- {
- public:
- Output_section_element_dot_assignment(Expression* val)
- : val_(val)
- { }
- // An assignment to dot within an output section is enough to force
- // the output section to exist.
- bool
- needs_output_section() const
- { return true; }
- // Finalize the symbol.
- void
- finalize_symbols(Symbol_table* symtab, const Layout* layout,
- uint64_t* dot_value, Output_section** dot_section)
- {
- *dot_value = this->val_->eval_with_dot(symtab, layout, true, *dot_value,
- *dot_section, dot_section, NULL,
- true);
- }
- // Update the dot symbol while setting section addresses.
- void
- set_section_addresses(Symbol_table* symtab, Layout* layout, Output_section*,
- uint64_t, uint64_t* dot_value, uint64_t*,
- Output_section** dot_section, std::string*,
- Input_section_list*);
- // Print for debugging.
- void
- print(FILE* f) const
- {
- fprintf(f, " . = ");
- this->val_->print(f);
- fprintf(f, "\n");
- }
- private:
- Expression* val_;
- };
- // Update the dot symbol while setting section addresses.
- void
- Output_section_element_dot_assignment::set_section_addresses(
- Symbol_table* symtab,
- Layout* layout,
- Output_section* output_section,
- uint64_t,
- uint64_t* dot_value,
- uint64_t* dot_alignment,
- Output_section** dot_section,
- std::string* fill,
- Input_section_list*)
- {
- uint64_t next_dot = this->val_->eval_with_dot(symtab, layout, false,
- *dot_value, *dot_section,
- dot_section, dot_alignment,
- true);
- if (next_dot < *dot_value)
- gold_error(_("dot may not move backward"));
- if (next_dot > *dot_value && output_section != NULL)
- {
- section_size_type length = convert_to_section_size_type(next_dot
- - *dot_value);
- Output_section_data* posd;
- if (fill->empty())
- posd = new Output_data_zero_fill(length, 0);
- else
- {
- std::string this_fill = this->get_fill_string(fill, length);
- posd = new Output_data_const(this_fill, 0);
- }
- output_section->add_output_section_data(posd);
- layout->new_output_section_data_from_script(posd);
- }
- *dot_value = next_dot;
- }
- // An assertion in an output section.
- class Output_section_element_assertion : public Output_section_element
- {
- public:
- Output_section_element_assertion(Expression* check, const char* message,
- size_t messagelen)
- : assertion_(check, message, messagelen)
- { }
- void
- print(FILE* f) const
- {
- fprintf(f, " ");
- this->assertion_.print(f);
- }
- private:
- Script_assertion assertion_;
- };
- // We use a special instance of Output_section_data to handle BYTE,
- // SHORT, etc. This permits forward references to symbols in the
- // expressions.
- class Output_data_expression : public Output_section_data
- {
- public:
- Output_data_expression(int size, bool is_signed, Expression* val,
- const Symbol_table* symtab, const Layout* layout,
- uint64_t dot_value, Output_section* dot_section)
- : Output_section_data(size, 0, true),
- is_signed_(is_signed), val_(val), symtab_(symtab),
- layout_(layout), dot_value_(dot_value), dot_section_(dot_section)
- { }
- protected:
- // Write the data to the output file.
- void
- do_write(Output_file*);
- // Write the data to a buffer.
- void
- do_write_to_buffer(unsigned char*);
- // Write to a map file.
- void
- do_print_to_mapfile(Mapfile* mapfile) const
- { mapfile->print_output_data(this, _("** expression")); }
- private:
- template<bool big_endian>
- void
- endian_write_to_buffer(uint64_t, unsigned char*);
- bool is_signed_;
- Expression* val_;
- const Symbol_table* symtab_;
- const Layout* layout_;
- uint64_t dot_value_;
- Output_section* dot_section_;
- };
- // Write the data element to the output file.
- void
- Output_data_expression::do_write(Output_file* of)
- {
- unsigned char* view = of->get_output_view(this->offset(), this->data_size());
- this->write_to_buffer(view);
- of->write_output_view(this->offset(), this->data_size(), view);
- }
- // Write the data element to a buffer.
- void
- Output_data_expression::do_write_to_buffer(unsigned char* buf)
- {
- uint64_t val = this->val_->eval_with_dot(this->symtab_, this->layout_,
- true, this->dot_value_,
- this->dot_section_, NULL, NULL,
- false);
- if (parameters->target().is_big_endian())
- this->endian_write_to_buffer<true>(val, buf);
- else
- this->endian_write_to_buffer<false>(val, buf);
- }
- template<bool big_endian>
- void
- Output_data_expression::endian_write_to_buffer(uint64_t val,
- unsigned char* buf)
- {
- switch (this->data_size())
- {
- case 1:
- elfcpp::Swap_unaligned<8, big_endian>::writeval(buf, val);
- break;
- case 2:
- elfcpp::Swap_unaligned<16, big_endian>::writeval(buf, val);
- break;
- case 4:
- elfcpp::Swap_unaligned<32, big_endian>::writeval(buf, val);
- break;
- case 8:
- if (parameters->target().get_size() == 32)
- {
- val &= 0xffffffff;
- if (this->is_signed_ && (val & 0x80000000) != 0)
- val |= 0xffffffff00000000LL;
- }
- elfcpp::Swap_unaligned<64, big_endian>::writeval(buf, val);
- break;
- default:
- gold_unreachable();
- }
- }
- // A data item in an output section.
- class Output_section_element_data : public Output_section_element
- {
- public:
- Output_section_element_data(int size, bool is_signed, Expression* val)
- : size_(size), is_signed_(is_signed), val_(val)
- { }
- // If there is a data item, then we must create an output section.
- bool
- needs_output_section() const
- { return true; }
- // Finalize symbols--we just need to update dot.
- void
- finalize_symbols(Symbol_table*, const Layout*, uint64_t* dot_value,
- Output_section**)
- { *dot_value += this->size_; }
- // Store the value in the section.
- void
- set_section_addresses(Symbol_table*, Layout*, Output_section*, uint64_t,
- uint64_t* dot_value, uint64_t*, Output_section**,
- std::string*, Input_section_list*);
- // Print for debugging.
- void
- print(FILE*) const;
- private:
- // The size in bytes.
- int size_;
- // Whether the value is signed.
- bool is_signed_;
- // The value.
- Expression* val_;
- };
- // Store the value in the section.
- void
- Output_section_element_data::set_section_addresses(
- Symbol_table* symtab,
- Layout* layout,
- Output_section* os,
- uint64_t,
- uint64_t* dot_value,
- uint64_t*,
- Output_section** dot_section,
- std::string*,
- Input_section_list*)
- {
- gold_assert(os != NULL);
- Output_data_expression* expression =
- new Output_data_expression(this->size_, this->is_signed_, this->val_,
- symtab, layout, *dot_value, *dot_section);
- os->add_output_section_data(expression);
- layout->new_output_section_data_from_script(expression);
- *dot_value += this->size_;
- }
- // Print for debugging.
- void
- Output_section_element_data::print(FILE* f) const
- {
- const char* s;
- switch (this->size_)
- {
- case 1:
- s = "BYTE";
- break;
- case 2:
- s = "SHORT";
- break;
- case 4:
- s = "LONG";
- break;
- case 8:
- if (this->is_signed_)
- s = "SQUAD";
- else
- s = "QUAD";
- break;
- default:
- gold_unreachable();
- }
- fprintf(f, " %s(", s);
- this->val_->print(f);
- fprintf(f, ")\n");
- }
- // A fill value setting in an output section.
- class Output_section_element_fill : public Output_section_element
- {
- public:
- Output_section_element_fill(Expression* val)
- : val_(val)
- { }
- // Update the fill value while setting section addresses.
- void
- set_section_addresses(Symbol_table* symtab, Layout* layout, Output_section*,
- uint64_t, uint64_t* dot_value, uint64_t*,
- Output_section** dot_section,
- std::string* fill, Input_section_list*)
- {
- Output_section* fill_section;
- uint64_t fill_val = this->val_->eval_with_dot(symtab, layout, false,
- *dot_value, *dot_section,
- &fill_section, NULL, false);
- if (fill_section != NULL)
- gold_warning(_("fill value is not absolute"));
- // FIXME: The GNU linker supports fill values of arbitrary length.
- unsigned char fill_buff[4];
- elfcpp::Swap_unaligned<32, true>::writeval(fill_buff, fill_val);
- fill->assign(reinterpret_cast<char*>(fill_buff), 4);
- }
- // Print for debugging.
- void
- print(FILE* f) const
- {
- fprintf(f, " FILL(");
- this->val_->print(f);
- fprintf(f, ")\n");
- }
- private:
- // The new fill value.
- Expression* val_;
- };
- // An input section specification in an output section
- class Output_section_element_input : public Output_section_element
- {
- public:
- Output_section_element_input(const Input_section_spec* spec, bool keep);
- // Finalize symbols--just update the value of the dot symbol.
- void
- finalize_symbols(Symbol_table*, const Layout*, uint64_t* dot_value,
- Output_section** dot_section)
- {
- *dot_value = this->final_dot_value_;
- *dot_section = this->final_dot_section_;
- }
- // See whether we match FILE_NAME and SECTION_NAME as an input section.
- // If we do then also indicate whether the section should be KEPT.
- bool
- match_name(const char* file_name, const char* section_name, bool* keep) const;
- // Set the section address.
- void
- set_section_addresses(Symbol_table* symtab, Layout* layout, Output_section*,
- uint64_t subalign, uint64_t* dot_value, uint64_t*,
- Output_section**, std::string* fill,
- Input_section_list*);
- // Print for debugging.
- void
- print(FILE* f) const;
- private:
- // An input section pattern.
- struct Input_section_pattern
- {
- std::string pattern;
- bool pattern_is_wildcard;
- Sort_wildcard sort;
- Input_section_pattern(const char* patterna, size_t patternlena,
- Sort_wildcard sorta)
- : pattern(patterna, patternlena),
- pattern_is_wildcard(is_wildcard_string(this->pattern.c_str())),
- sort(sorta)
- { }
- };
- typedef std::vector<Input_section_pattern> Input_section_patterns;
- // Filename_exclusions is a pair of filename pattern and a bool
- // indicating whether the filename is a wildcard.
- typedef std::vector<std::pair<std::string, bool> > Filename_exclusions;
- // Return whether STRING matches PATTERN, where IS_WILDCARD_PATTERN
- // indicates whether this is a wildcard pattern.
- static inline bool
- match(const char* string, const char* pattern, bool is_wildcard_pattern)
- {
- return (is_wildcard_pattern
- ? fnmatch(pattern, string, 0) == 0
- : strcmp(string, pattern) == 0);
- }
- // See if we match a file name.
- bool
- match_file_name(const char* file_name) const;
- // The file name pattern. If this is the empty string, we match all
- // files.
- std::string filename_pattern_;
- // Whether the file name pattern is a wildcard.
- bool filename_is_wildcard_;
- // How the file names should be sorted. This may only be
- // SORT_WILDCARD_NONE or SORT_WILDCARD_BY_NAME.
- Sort_wildcard filename_sort_;
- // The list of file names to exclude.
- Filename_exclusions filename_exclusions_;
- // The list of input section patterns.
- Input_section_patterns input_section_patterns_;
- // Whether to keep this section when garbage collecting.
- bool keep_;
- // The value of dot after including all matching sections.
- uint64_t final_dot_value_;
- // The section where dot is defined after including all matching
- // sections.
- Output_section* final_dot_section_;
- };
- // Construct Output_section_element_input. The parser records strings
- // as pointers into a copy of the script file, which will go away when
- // parsing is complete. We make sure they are in std::string objects.
- Output_section_element_input::Output_section_element_input(
- const Input_section_spec* spec,
- bool keep)
- : filename_pattern_(),
- filename_is_wildcard_(false),
- filename_sort_(spec->file.sort),
- filename_exclusions_(),
- input_section_patterns_(),
- keep_(keep),
- final_dot_value_(0),
- final_dot_section_(NULL)
- {
- // The filename pattern "*" is common, and matches all files. Turn
- // it into the empty string.
- if (spec->file.name.length != 1 || spec->file.name.value[0] != '*')
- this->filename_pattern_.assign(spec->file.name.value,
- spec->file.name.length);
- this->filename_is_wildcard_ = is_wildcard_string(this->filename_pattern_.c_str());
- if (spec->input_sections.exclude != NULL)
- {
- for (String_list::const_iterator p =
- spec->input_sections.exclude->begin();
- p != spec->input_sections.exclude->end();
- ++p)
- {
- bool is_wildcard = is_wildcard_string((*p).c_str());
- this->filename_exclusions_.push_back(std::make_pair(*p,
- is_wildcard));
- }
- }
- if (spec->input_sections.sections != NULL)
- {
- Input_section_patterns& isp(this->input_section_patterns_);
- for (String_sort_list::const_iterator p =
- spec->input_sections.sections->begin();
- p != spec->input_sections.sections->end();
- ++p)
- isp.push_back(Input_section_pattern(p->name.value, p->name.length,
- p->sort));
- }
- }
- // See whether we match FILE_NAME.
- bool
- Output_section_element_input::match_file_name(const char* file_name) const
- {
- if (!this->filename_pattern_.empty())
- {
- // If we were called with no filename, we refuse to match a
- // pattern which requires a file name.
- if (file_name == NULL)
- return false;
- if (!match(file_name, this->filename_pattern_.c_str(),
- this->filename_is_wildcard_))
- return false;
- }
- if (file_name != NULL)
- {
- // Now we have to see whether FILE_NAME matches one of the
- // exclusion patterns, if any.
- for (Filename_exclusions::const_iterator p =
- this->filename_exclusions_.begin();
- p != this->filename_exclusions_.end();
- ++p)
- {
- if (match(file_name, p->first.c_str(), p->second))
- return false;
- }
- }
- return true;
- }
- // See whether we match FILE_NAME and SECTION_NAME. If we do then
- // KEEP indicates whether the section should survive garbage collection.
- bool
- Output_section_element_input::match_name(const char* file_name,
- const char* section_name,
- bool *keep) const
- {
- if (!this->match_file_name(file_name))
- return false;
- *keep = this->keep_;
- // If there are no section name patterns, then we match.
- if (this->input_section_patterns_.empty())
- return true;
- // See whether we match the section name patterns.
- for (Input_section_patterns::const_iterator p =
- this->input_section_patterns_.begin();
- p != this->input_section_patterns_.end();
- ++p)
- {
- if (match(section_name, p->pattern.c_str(), p->pattern_is_wildcard))
- return true;
- }
- // We didn't match any section names, so we didn't match.
- return false;
- }
- // Information we use to sort the input sections.
- class Input_section_info
- {
- public:
- Input_section_info(const Output_section::Input_section& input_section)
- : input_section_(input_section), section_name_(),
- size_(0), addralign_(1)
- { }
- // Return the simple input section.
- const Output_section::Input_section&
- input_section() const
- { return this->input_section_; }
- // Return the object.
- Relobj*
- relobj() const
- { return this->input_section_.relobj(); }
- // Return the section index.
- unsigned int
- shndx()
- { return this->input_section_.shndx(); }
- // Return the section name.
- const std::string&
- section_name() const
- { return this->section_name_; }
- // Set the section name.
- void
- set_section_name(const std::string name)
- {
- if (is_compressed_debug_section(name.c_str()))
- this->section_name_ = corresponding_uncompressed_section_name(name);
- else
- this->section_name_ = name;
- }
- // Return the section size.
- uint64_t
- size() const
- { return this->size_; }
- // Set the section size.
- void
- set_size(uint64_t size)
- { this->size_ = size; }
- // Return the address alignment.
- uint64_t
- addralign() const
- { return this->addralign_; }
- // Set the address alignment.
- void
- set_addralign(uint64_t addralign)
- { this->addralign_ = addralign; }
- private:
- // Input section, can be a relaxed section.
- Output_section::Input_section input_section_;
- // Name of the section.
- std::string section_name_;
- // Section size.
- uint64_t size_;
- // Address alignment.
- uint64_t addralign_;
- };
- // A class to sort the input sections.
- class Input_section_sorter
- {
- public:
- Input_section_sorter(Sort_wildcard filename_sort, Sort_wildcard section_sort)
- : filename_sort_(filename_sort), section_sort_(section_sort)
- { }
- bool
- operator()(const Input_section_info&, const Input_section_info&) const;
- private:
- static unsigned long
- get_init_priority(const char*);
- Sort_wildcard filename_sort_;
- Sort_wildcard section_sort_;
- };
- // Return a relative priority of the section with the specified NAME
- // (a lower value meand a higher priority), or 0 if it should be compared
- // with others as strings.
- // The implementation of this function is copied from ld/ldlang.c.
- unsigned long
- Input_section_sorter::get_init_priority(const char* name)
- {
- char* end;
- unsigned long init_priority;
- // GCC uses the following section names for the init_priority
- // attribute with numerical values 101 and 65535 inclusive. A
- // lower value means a higher priority.
- //
- // 1: .init_array.NNNN/.fini_array.NNNN: Where NNNN is the
- // decimal numerical value of the init_priority attribute.
- // The order of execution in .init_array is forward and
- // .fini_array is backward.
- // 2: .ctors.NNNN/.dtors.NNNN: Where NNNN is 65535 minus the
- // decimal numerical value of the init_priority attribute.
- // The order of execution in .ctors is backward and .dtors
- // is forward.
- if (strncmp(name, ".init_array.", 12) == 0
- || strncmp(name, ".fini_array.", 12) == 0)
- {
- init_priority = strtoul(name + 12, &end, 10);
- return *end ? 0 : init_priority;
- }
- else if (strncmp(name, ".ctors.", 7) == 0
- || strncmp(name, ".dtors.", 7) == 0)
- {
- init_priority = strtoul(name + 7, &end, 10);
- return *end ? 0 : 65535 - init_priority;
- }
- return 0;
- }
- bool
- Input_section_sorter::operator()(const Input_section_info& isi1,
- const Input_section_info& isi2) const
- {
- if (this->section_sort_ == SORT_WILDCARD_BY_INIT_PRIORITY)
- {
- unsigned long ip1 = get_init_priority(isi1.section_name().c_str());
- unsigned long ip2 = get_init_priority(isi2.section_name().c_str());
- if (ip1 != 0 && ip2 != 0 && ip1 != ip2)
- return ip1 < ip2;
- }
- if (this->section_sort_ == SORT_WILDCARD_BY_NAME
- || this->section_sort_ == SORT_WILDCARD_BY_NAME_BY_ALIGNMENT
- || (this->section_sort_ == SORT_WILDCARD_BY_ALIGNMENT_BY_NAME
- && isi1.addralign() == isi2.addralign())
- || this->section_sort_ == SORT_WILDCARD_BY_INIT_PRIORITY)
- {
- if (isi1.section_name() != isi2.section_name())
- return isi1.section_name() < isi2.section_name();
- }
- if (this->section_sort_ == SORT_WILDCARD_BY_ALIGNMENT
- || this->section_sort_ == SORT_WILDCARD_BY_NAME_BY_ALIGNMENT
- || this->section_sort_ == SORT_WILDCARD_BY_ALIGNMENT_BY_NAME)
- {
- if (isi1.addralign() != isi2.addralign())
- return isi1.addralign() < isi2.addralign();
- }
- if (this->filename_sort_ == SORT_WILDCARD_BY_NAME)
- {
- if (isi1.relobj()->name() != isi2.relobj()->name())
- return (isi1.relobj()->name() < isi2.relobj()->name());
- }
- // Otherwise we leave them in the same order.
- return false;
- }
- // Set the section address. Look in INPUT_SECTIONS for sections which
- // match this spec, sort them as specified, and add them to the output
- // section.
- void
- Output_section_element_input::set_section_addresses(
- Symbol_table*,
- Layout* layout,
- Output_section* output_section,
- uint64_t subalign,
- uint64_t* dot_value,
- uint64_t*,
- Output_section** dot_section,
- std::string* fill,
- Input_section_list* input_sections)
- {
- // We build a list of sections which match each
- // Input_section_pattern.
- // If none of the patterns specify a sort option, we throw all
- // matching input sections into a single bin, in the order we
- // find them. Otherwise, we put matching input sections into
- // a separate bin for each pattern, and sort each one as
- // specified. Thus, an input section spec like this:
- // *(.foo .bar)
- // will group all .foo and .bar sections in the order seen,
- // whereas this:
- // *(.foo) *(.bar)
- // will group all .foo sections followed by all .bar sections.
- // This matches Gnu ld behavior.
- // Things get really weird, though, when you add a sort spec
- // on some, but not all, of the patterns, like this:
- // *(SORT_BY_NAME(.foo) .bar)
- // We do not attempt to match Gnu ld behavior in this case.
- typedef std::vector<std::vector<Input_section_info> > Matching_sections;
- size_t input_pattern_count = this->input_section_patterns_.size();
- size_t bin_count = 1;
- bool any_patterns_with_sort = false;
- for (size_t i = 0; i < input_pattern_count; ++i)
- {
- const Input_section_pattern& isp(this->input_section_patterns_[i]);
- if (isp.sort != SORT_WILDCARD_NONE)
- any_patterns_with_sort = true;
- }
- if (any_patterns_with_sort)
- bin_count = input_pattern_count;
- Matching_sections matching_sections(bin_count);
- // Look through the list of sections for this output section. Add
- // each one which matches to one of the elements of
- // MATCHING_SECTIONS.
- Input_section_list::iterator p = input_sections->begin();
- while (p != input_sections->end())
- {
- Relobj* relobj = p->relobj();
- unsigned int shndx = p->shndx();
- Input_section_info isi(*p);
- // Calling section_name and section_addralign is not very
- // efficient.
- // Lock the object so that we can get information about the
- // section. This is OK since we know we are single-threaded
- // here.
- {
- const Task* task = reinterpret_cast<const Task*>(-1);
- Task_lock_obj<Object> tl(task, relobj);
- isi.set_section_name(relobj->section_name(shndx));
- if (p->is_relaxed_input_section())
- {
- // We use current data size because relaxed section sizes may not
- // have finalized yet.
- isi.set_size(p->relaxed_input_section()->current_data_size());
- isi.set_addralign(p->relaxed_input_section()->addralign());
- }
- else
- {
- isi.set_size(relobj->section_size(shndx));
- isi.set_addralign(relobj->section_addralign(shndx));
- }
- }
- if (!this->match_file_name(relobj->name().c_str()))
- ++p;
- else if (this->input_section_patterns_.empty())
- {
- matching_sections[0].push_back(isi);
- p = input_sections->erase(p);
- }
- else
- {
- size_t i;
- for (i = 0; i < input_pattern_count; ++i)
- {
- const Input_section_pattern&
- isp(this->input_section_patterns_[i]);
- if (match(isi.section_name().c_str(), isp.pattern.c_str(),
- isp.pattern_is_wildcard))
- break;
- }
- if (i >= input_pattern_count)
- ++p;
- else
- {
- if (i >= bin_count)
- i = 0;
- matching_sections[i].push_back(isi);
- p = input_sections->erase(p);
- }
- }
- }
- // Look through MATCHING_SECTIONS. Sort each one as specified,
- // using a stable sort so that we get the default order when
- // sections are otherwise equal. Add each input section to the
- // output section.
- uint64_t dot = *dot_value;
- for (size_t i = 0; i < bin_count; ++i)
- {
- if (matching_sections[i].empty())
- continue;
- gold_assert(output_section != NULL);
- const Input_section_pattern& isp(this->input_section_patterns_[i]);
- if (isp.sort != SORT_WILDCARD_NONE
- || this->filename_sort_ != SORT_WILDCARD_NONE)
- std::stable_sort(matching_sections[i].begin(),
- matching_sections[i].end(),
- Input_section_sorter(this->filename_sort_,
- isp.sort));
- for (std::vector<Input_section_info>::const_iterator p =
- matching_sections[i].begin();
- p != matching_sections[i].end();
- ++p)
- {
- // Override the original address alignment if SUBALIGN is specified.
- // We need to make a copy of the input section to modify the
- // alignment.
- Output_section::Input_section sis(p->input_section());
- uint64_t this_subalign = sis.addralign();
- if (!sis.is_input_section())
- sis.output_section_data()->finalize_data_size();
- uint64_t data_size = sis.data_size();
- if (subalign > 0)
- {
- this_subalign = subalign;
- sis.set_addralign(subalign);
- }
- uint64_t address = align_address(dot, this_subalign);
- if (address > dot && !fill->empty())
- {
- section_size_type length =
- convert_to_section_size_type(address - dot);
- std::string this_fill = this->get_fill_string(fill, length);
- Output_section_data* posd = new Output_data_const(this_fill, 0);
- output_section->add_output_section_data(posd);
- layout->new_output_section_data_from_script(posd);
- }
- output_section->add_script_input_section(sis);
- dot = address + data_size;
- }
- }
- // An SHF_TLS/SHT_NOBITS section does not take up any
- // address space.
- if (output_section == NULL
- || (output_section->flags() & elfcpp::SHF_TLS) == 0
- || output_section->type() != elfcpp::SHT_NOBITS)
- *dot_value = dot;
- this->final_dot_value_ = *dot_value;
- this->final_dot_section_ = *dot_section;
- }
- // Print for debugging.
- void
- Output_section_element_input::print(FILE* f) const
- {
- fprintf(f, " ");
- if (this->keep_)
- fprintf(f, "KEEP(");
- if (!this->filename_pattern_.empty())
- {
- bool need_close_paren = false;
- switch (this->filename_sort_)
- {
- case SORT_WILDCARD_NONE:
- break;
- case SORT_WILDCARD_BY_NAME:
- fprintf(f, "SORT_BY_NAME(");
- need_close_paren = true;
- break;
- default:
- gold_unreachable();
- }
- fprintf(f, "%s", this->filename_pattern_.c_str());
- if (need_close_paren)
- fprintf(f, ")");
- }
- if (!this->input_section_patterns_.empty()
- || !this->filename_exclusions_.empty())
- {
- fprintf(f, "(");
- bool need_space = false;
- if (!this->filename_exclusions_.empty())
- {
- fprintf(f, "EXCLUDE_FILE(");
- bool need_comma = false;
- for (Filename_exclusions::const_iterator p =
- this->filename_exclusions_.begin();
- p != this->filename_exclusions_.end();
- ++p)
- {
- if (need_comma)
- fprintf(f, ", ");
- fprintf(f, "%s", p->first.c_str());
- need_comma = true;
- }
- fprintf(f, ")");
- need_space = true;
- }
- for (Input_section_patterns::const_iterator p =
- this->input_section_patterns_.begin();
- p != this->input_section_patterns_.end();
- ++p)
- {
- if (need_space)
- fprintf(f, " ");
- int close_parens = 0;
- switch (p->sort)
- {
- case SORT_WILDCARD_NONE:
- break;
- case SORT_WILDCARD_BY_NAME:
- fprintf(f, "SORT_BY_NAME(");
- close_parens = 1;
- break;
- case SORT_WILDCARD_BY_ALIGNMENT:
- fprintf(f, "SORT_BY_ALIGNMENT(");
- close_parens = 1;
- break;
- case SORT_WILDCARD_BY_NAME_BY_ALIGNMENT:
- fprintf(f, "SORT_BY_NAME(SORT_BY_ALIGNMENT(");
- close_parens = 2;
- break;
- case SORT_WILDCARD_BY_ALIGNMENT_BY_NAME:
- fprintf(f, "SORT_BY_ALIGNMENT(SORT_BY_NAME(");
- close_parens = 2;
- break;
- case SORT_WILDCARD_BY_INIT_PRIORITY:
- fprintf(f, "SORT_BY_INIT_PRIORITY(");
- close_parens = 1;
- break;
- default:
- gold_unreachable();
- }
- fprintf(f, "%s", p->pattern.c_str());
- for (int i = 0; i < close_parens; ++i)
- fprintf(f, ")");
- need_space = true;
- }
- fprintf(f, ")");
- }
- if (this->keep_)
- fprintf(f, ")");
- fprintf(f, "\n");
- }
- // An output section.
- class Output_section_definition : public Sections_element
- {
- public:
- typedef Output_section_element::Input_section_list Input_section_list;
- Output_section_definition(const char* name, size_t namelen,
- const Parser_output_section_header* header);
- // Finish the output section with the information in the trailer.
- void
- finish(const Parser_output_section_trailer* trailer);
- // Add a symbol to be defined.
- void
- add_symbol_assignment(const char* name, size_t length, Expression* value,
- bool provide, bool hidden);
- // Add an assignment to the special dot symbol.
- void
- add_dot_assignment(Expression* value);
- // Add an assertion.
- void
- add_assertion(Expression* check, const char* message, size_t messagelen);
- // Add a data item to the current output section.
- void
- add_data(int size, bool is_signed, Expression* val);
- // Add a setting for the fill value.
- void
- add_fill(Expression* val);
- // Add an input section specification.
- void
- add_input_section(const Input_section_spec* spec, bool keep);
- // Return whether the output section is relro.
- bool
- is_relro() const
- { return this->is_relro_; }
- // Record that the output section is relro.
- void
- set_is_relro()
- { this->is_relro_ = true; }
- // Create any required output sections.
- void
- create_sections(Layout*);
- // Add any symbols being defined to the symbol table.
- void
- add_symbols_to_table(Symbol_table* symtab);
- // Finalize symbols and check assertions.
- void
- finalize_symbols(Symbol_table*, const Layout*, uint64_t*);
- // Return the output section name to use for an input file name and
- // section name.
- const char*
- output_section_name(const char* file_name, const char* section_name,
- Output_section***, Script_sections::Section_type*,
- bool*, bool);
- // Initialize OSP with an output section.
- void
- orphan_section_init(Orphan_section_placement* osp,
- Script_sections::Elements_iterator p)
- { osp->output_section_init(this->name_, this->output_section_, p); }
- // Set the section address.
- void
- set_section_addresses(Symbol_table* symtab, Layout* layout,
- uint64_t* dot_value, uint64_t*,
- uint64_t* load_address);
- // Check a constraint (ONLY_IF_RO, etc.) on an output section. If
- // this section is constrained, and the input sections do not match,
- // return the constraint, and set *POSD.
- Section_constraint
- check_constraint(Output_section_definition** posd);
- // See if this is the alternate output section for a constrained
- // output section. If it is, transfer the Output_section and return
- // true. Otherwise return false.
- bool
- alternate_constraint(Output_section_definition*, Section_constraint);
- // Get the list of segments to use for an allocated section when
- // using a PHDRS clause.
- Output_section*
- allocate_to_segment(String_list** phdrs_list, bool* orphan);
- // Look for an output section by name and return the address, the
- // load address, the alignment, and the size. This is used when an
- // expression refers to an output section which was not actually
- // created. This returns true if the section was found, false
- // otherwise.
- bool
- get_output_section_info(const char*, uint64_t*, uint64_t*, uint64_t*,
- uint64_t*) const;
- // Return the associated Output_section if there is one.
- Output_section*
- get_output_section() const
- { return this->output_section_; }
- // Print the contents to the FILE. This is for debugging.
- void
- print(FILE*) const;
- // Return the output section type if specified or Script_sections::ST_NONE.
- Script_sections::Section_type
- section_type() const;
- // Store the memory region to use.
- void
- set_memory_region(Memory_region*, bool set_vma);
- void
- set_section_vma(Expression* address)
- { this->address_ = address; }
- void
- set_section_lma(Expression* address)
- { this->load_address_ = address; }
- const std::string&
- get_section_name() const
- { return this->name_; }
- private:
- static const char*
- script_section_type_name(Script_section_type);
- typedef std::vector<Output_section_element*> Output_section_elements;
- // The output section name.
- std::string name_;
- // The address. This may be NULL.
- Expression* address_;
- // The load address. This may be NULL.
- Expression* load_address_;
- // The alignment. This may be NULL.
- Expression* align_;
- // The input section alignment. This may be NULL.
- Expression* subalign_;
- // The constraint, if any.
- Section_constraint constraint_;
- // The fill value. This may be NULL.
- Expression* fill_;
- // The list of segments this section should go into. This may be
- // NULL.
- String_list* phdrs_;
- // The list of elements defining the section.
- Output_section_elements elements_;
- // The Output_section created for this definition. This will be
- // NULL if none was created.
- Output_section* output_section_;
- // The address after it has been evaluated.
- uint64_t evaluated_address_;
- // The load address after it has been evaluated.
- uint64_t evaluated_load_address_;
- // The alignment after it has been evaluated.
- uint64_t evaluated_addralign_;
- // The output section is relro.
- bool is_relro_;
- // The output section type if specified.
- enum Script_section_type script_section_type_;
- };
- // Constructor.
- Output_section_definition::Output_section_definition(
- const char* name,
- size_t namelen,
- const Parser_output_section_header* header)
- : name_(name, namelen),
- address_(header->address),
- load_address_(header->load_address),
- align_(header->align),
- subalign_(header->subalign),
- constraint_(header->constraint),
- fill_(NULL),
- phdrs_(NULL),
- elements_(),
- output_section_(NULL),
- evaluated_address_(0),
- evaluated_load_address_(0),
- evaluated_addralign_(0),
- is_relro_(false),
- script_section_type_(header->section_type)
- {
- }
- // Finish an output section.
- void
- Output_section_definition::finish(const Parser_output_section_trailer* trailer)
- {
- this->fill_ = trailer->fill;
- this->phdrs_ = trailer->phdrs;
- }
- // Add a symbol to be defined.
- void
- Output_section_definition::add_symbol_assignment(const char* name,
- size_t length,
- Expression* value,
- bool provide,
- bool hidden)
- {
- Output_section_element* p = new Output_section_element_assignment(name,
- length,
- value,
- provide,
- hidden);
- this->elements_.push_back(p);
- }
- // Add an assignment to the special dot symbol.
- void
- Output_section_definition::add_dot_assignment(Expression* value)
- {
- Output_section_element* p = new Output_section_element_dot_assignment(value);
- this->elements_.push_back(p);
- }
- // Add an assertion.
- void
- Output_section_definition::add_assertion(Expression* check,
- const char* message,
- size_t messagelen)
- {
- Output_section_element* p = new Output_section_element_assertion(check,
- message,
- messagelen);
- this->elements_.push_back(p);
- }
- // Add a data item to the current output section.
- void
- Output_section_definition::add_data(int size, bool is_signed, Expression* val)
- {
- Output_section_element* p = new Output_section_element_data(size, is_signed,
- val);
- this->elements_.push_back(p);
- }
- // Add a setting for the fill value.
- void
- Output_section_definition::add_fill(Expression* val)
- {
- Output_section_element* p = new Output_section_element_fill(val);
- this->elements_.push_back(p);
- }
- // Add an input section specification.
- void
- Output_section_definition::add_input_section(const Input_section_spec* spec,
- bool keep)
- {
- Output_section_element* p = new Output_section_element_input(spec, keep);
- this->elements_.push_back(p);
- }
- // Create any required output sections. We need an output section if
- // there is a data statement here.
- void
- Output_section_definition::create_sections(Layout* layout)
- {
- if (this->output_section_ != NULL)
- return;
- for (Output_section_elements::const_iterator p = this->elements_.begin();
- p != this->elements_.end();
- ++p)
- {
- if ((*p)->needs_output_section())
- {
- const char* name = this->name_.c_str();
- this->output_section_ =
- layout->make_output_section_for_script(name, this->section_type());
- return;
- }
- }
- }
- // Add any symbols being defined to the symbol table.
- void
- Output_section_definition::add_symbols_to_table(Symbol_table* symtab)
- {
- for (Output_section_elements::iterator p = this->elements_.begin();
- p != this->elements_.end();
- ++p)
- (*p)->add_symbols_to_table(symtab);
- }
- // Finalize symbols and check assertions.
- void
- Output_section_definition::finalize_symbols(Symbol_table* symtab,
- const Layout* layout,
- uint64_t* dot_value)
- {
- if (this->output_section_ != NULL)
- *dot_value = this->output_section_->address();
- else
- {
- uint64_t address = *dot_value;
- if (this->address_ != NULL)
- {
- address = this->address_->eval_with_dot(symtab, layout, true,
- *dot_value, NULL,
- NULL, NULL, false);
- }
- if (this->align_ != NULL)
- {
- uint64_t align = this->align_->eval_with_dot(symtab, layout, true,
- *dot_value, NULL,
- NULL, NULL, false);
- address = align_address(address, align);
- }
- *dot_value = address;
- }
- Output_section* dot_section = this->output_section_;
- for (Output_section_elements::iterator p = this->elements_.begin();
- p != this->elements_.end();
- ++p)
- (*p)->finalize_symbols(symtab, layout, dot_value, &dot_section);
- }
- // Return the output section name to use for an input section name.
- const char*
- Output_section_definition::output_section_name(
- const char* file_name,
- const char* section_name,
- Output_section*** slot,
- Script_sections::Section_type* psection_type,
- bool* keep,
- bool match_input_spec)
- {
- // If the section is a linker-created output section, just look for a match
- // on the output section name.
- if (!match_input_spec && this->name_ != "/DISCARD/")
- {
- if (this->name_ != section_name)
- return NULL;
- *slot = &this->output_section_;
- *psection_type = this->section_type();
- return this->name_.c_str();
- }
- // Ask each element whether it matches NAME.
- for (Output_section_elements::const_iterator p = this->elements_.begin();
- p != this->elements_.end();
- ++p)
- {
- if ((*p)->match_name(file_name, section_name, keep))
- {
- // We found a match for NAME, which means that it should go
- // into this output section.
- *slot = &this->output_section_;
- *psection_type = this->section_type();
- return this->name_.c_str();
- }
- }
- // We don't know about this section name.
- return NULL;
- }
- // Return true if memory from START to START + LENGTH is contained
- // within a memory region.
- bool
- Script_sections::block_in_region(Symbol_table* symtab, Layout* layout,
- uint64_t start, uint64_t length) const
- {
- if (this->memory_regions_ == NULL)
- return false;
- for (Memory_regions::const_iterator mr = this->memory_regions_->begin();
- mr != this->memory_regions_->end();
- ++mr)
- {
- uint64_t s = (*mr)->start_address()->eval(symtab, layout, false);
- uint64_t l = (*mr)->length()->eval(symtab, layout, false);
- if (s <= start
- && (s + l) >= (start + length))
- return true;
- }
- return false;
- }
- // Find a memory region that should be used by a given output SECTION.
- // If provided set PREVIOUS_SECTION_RETURN to point to the last section
- // that used the return memory region.
- Memory_region*
- Script_sections::find_memory_region(
- Output_section_definition* section,
- bool find_vma_region,
- bool explicit_only,
- Output_section_definition** previous_section_return)
- {
- if (previous_section_return != NULL)
- * previous_section_return = NULL;
- // Walk the memory regions specified in this script, if any.
- if (this->memory_regions_ == NULL)
- return NULL;
- // The /DISCARD/ section never gets assigned to any region.
- if (section->get_section_name() == "/DISCARD/")
- return NULL;
- Memory_region* first_match = NULL;
- // First check to see if a region has been assigned to this section.
- for (Memory_regions::const_iterator mr = this->memory_regions_->begin();
- mr != this->memory_regions_->end();
- ++mr)
- {
- if (find_vma_region)
- {
- for (Memory_region::Section_list::const_iterator s =
- (*mr)->get_vma_section_list_start();
- s != (*mr)->get_vma_section_list_end();
- ++s)
- if ((*s) == section)
- {
- (*mr)->set_last_section(section);
- return *mr;
- }
- }
- else
- {
- for (Memory_region::Section_list::const_iterator s =
- (*mr)->get_lma_section_list_start();
- s != (*mr)->get_lma_section_list_end();
- ++s)
- if ((*s) == section)
- {
- (*mr)->set_last_section(section);
- return *mr;
- }
- }
- if (!explicit_only)
- {
- // Make a note of the first memory region whose attributes
- // are compatible with the section. If we do not find an
- // explicit region assignment, then we will return this region.
- Output_section* out_sec = section->get_output_section();
- if (first_match == NULL
- && out_sec != NULL
- && (*mr)->attributes_compatible(out_sec->flags(),
- out_sec->type()))
- first_match = *mr;
- }
- }
- // With LMA computations, if an explicit region has not been specified then
- // we will want to set the difference between the VMA and the LMA of the
- // section were searching for to be the same as the difference between the
- // VMA and LMA of the last section to be added to first matched region.
- // Hence, if it was asked for, we return a pointer to the last section
- // known to be used by the first matched region.
- if (first_match != NULL
- && previous_section_return != NULL)
- *previous_section_return = first_match->get_last_section();
- return first_match;
- }
- // Set the section address. Note that the OUTPUT_SECTION_ field will
- // be NULL if no input sections were mapped to this output section.
- // We still have to adjust dot and process symbol assignments.
- void
- Output_section_definition::set_section_addresses(Symbol_table* symtab,
- Layout* layout,
- uint64_t* dot_value,
- uint64_t* dot_alignment,
- uint64_t* load_address)
- {
- Memory_region* vma_region = NULL;
- Memory_region* lma_region = NULL;
- Script_sections* script_sections =
- layout->script_options()->script_sections();
- uint64_t address;
- uint64_t old_dot_value = *dot_value;
- uint64_t old_load_address = *load_address;
- // If input section sorting is requested via --section-ordering-file or
- // linker plugins, then do it here. This is important because we want
- // any sorting specified in the linker scripts, which will be done after
- // this, to take precedence. The final order of input sections is then
- // guaranteed to be according to the linker script specification.
- if (this->output_section_ != NULL
- && this->output_section_->input_section_order_specified())
- this->output_section_->sort_attached_input_sections();
- // Decide the start address for the section. The algorithm is:
- // 1) If an address has been specified in a linker script, use that.
- // 2) Otherwise if a memory region has been specified for the section,
- // use the next free address in the region.
- // 3) Otherwise if memory regions have been specified find the first
- // region whose attributes are compatible with this section and
- // install it into that region.
- // 4) Otherwise use the current location counter.
- if (this->output_section_ != NULL
- // Check for --section-start.
- && parameters->options().section_start(this->output_section_->name(),
- &address))
- ;
- else if (this->address_ == NULL)
- {
- vma_region = script_sections->find_memory_region(this, true, false, NULL);
- if (vma_region != NULL)
- address = vma_region->get_current_address()->eval(symtab, layout,
- false);
- else
- address = *dot_value;
- }
- else
- {
- vma_region = script_sections->find_memory_region(this, true, true, NULL);
- address = this->address_->eval_with_dot(symtab, layout, true,
- *dot_value, NULL, NULL,
- dot_alignment, false);
- if (vma_region != NULL)
- vma_region->set_address(address, symtab, layout);
- }
- uint64_t align;
- if (this->align_ == NULL)
- {
- if (this->output_section_ == NULL)
- align = 0;
- else
- align = this->output_section_->addralign();
- }
- else
- {
- Output_section* align_section;
- align = this->align_->eval_with_dot(symtab, layout, true, *dot_value,
- NULL, &align_section, NULL, false);
- if (align_section != NULL)
- gold_warning(_("alignment of section %s is not absolute"),
- this->name_.c_str());
- if (this->output_section_ != NULL)
- this->output_section_->set_addralign(align);
- }
- uint64_t subalign;
- if (this->subalign_ == NULL)
- subalign = 0;
- else
- {
- Output_section* subalign_section;
- subalign = this->subalign_->eval_with_dot(symtab, layout, true,
- *dot_value, NULL,
- &subalign_section, NULL,
- false);
- if (subalign_section != NULL)
- gold_warning(_("subalign of section %s is not absolute"),
- this->name_.c_str());
- // Reserve a value of 0 to mean there is no SUBALIGN property.
- if (subalign == 0)
- subalign = 1;
- // The external alignment of the output section must be at least
- // as large as that of the input sections. If there is no
- // explicit ALIGN property, we set the output section alignment
- // to match the input section alignment.
- if (align < subalign || this->align_ == NULL)
- {
- align = subalign;
- this->output_section_->set_addralign(align);
- }
- }
- address = align_address(address, align);
- uint64_t start_address = address;
- *dot_value = address;
- // Except for NOLOAD sections, the address of non-SHF_ALLOC sections is
- // forced to zero, regardless of what the linker script wants.
- if (this->output_section_ != NULL
- && ((this->output_section_->flags() & elfcpp::SHF_ALLOC) != 0
- || this->output_section_->is_noload()))
- this->output_section_->set_address(address);
- this->evaluated_address_ = address;
- this->evaluated_addralign_ = align;
- uint64_t laddr;
- if (this->load_address_ == NULL)
- {
- Output_section_definition* previous_section;
- // Determine if an LMA region has been set for this section.
- lma_region = script_sections->find_memory_region(this, false, false,
- &previous_section);
- if (lma_region != NULL)
- {
- if (previous_section == NULL)
- // The LMA address was explicitly set to the given region.
- laddr = lma_region->get_current_address()->eval(symtab, layout,
- false);
- else
- {
- // We are not going to use the discovered lma_region, so
- // make sure that we do not update it in the code below.
- lma_region = NULL;
- if (this->address_ != NULL || previous_section == this)
- {
- // Either an explicit VMA address has been set, or an
- // explicit VMA region has been set, so set the LMA equal to
- // the VMA.
- laddr = address;
- }
- else
- {
- // The LMA address was not explicitly or implicitly set.
- //
- // We have been given the first memory region that is
- // compatible with the current section and a pointer to the
- // last section to use this region. Set the LMA of this
- // section so that the difference between its' VMA and LMA
- // is the same as the difference between the VMA and LMA of
- // the last section in the given region.
- laddr = address + (previous_section->evaluated_load_address_
- - previous_section->evaluated_address_);
- }
- }
- if (this->output_section_ != NULL)
- this->output_section_->set_load_address(laddr);
- }
- else
- {
- // Do not set the load address of the output section, if one exists.
- // This allows future sections to determine what the load address
- // should be. If none is ever set, it will default to being the
- // same as the vma address.
- laddr = address;
- }
- }
- else
- {
- laddr = this->load_address_->eval_with_dot(symtab, layout, true,
- *dot_value,
- this->output_section_,
- NULL, NULL, false);
- if (this->output_section_ != NULL)
- this->output_section_->set_load_address(laddr);
- }
- this->evaluated_load_address_ = laddr;
- std::string fill;
- if (this->fill_ != NULL)
- {
- // FIXME: The GNU linker supports fill values of arbitrary
- // length.
- Output_section* fill_section;
- uint64_t fill_val = this->fill_->eval_with_dot(symtab, layout, true,
- *dot_value,
- NULL, &fill_section,
- NULL, false);
- if (fill_section != NULL)
- gold_warning(_("fill of section %s is not absolute"),
- this->name_.c_str());
- unsigned char fill_buff[4];
- elfcpp::Swap_unaligned<32, true>::writeval(fill_buff, fill_val);
- fill.assign(reinterpret_cast<char*>(fill_buff), 4);
- }
- Input_section_list input_sections;
- if (this->output_section_ != NULL)
- {
- // Get the list of input sections attached to this output
- // section. This will leave the output section with only
- // Output_section_data entries.
- address += this->output_section_->get_input_sections(address,
- fill,
- &input_sections);
- *dot_value = address;
- }
- Output_section* dot_section = this->output_section_;
- for (Output_section_elements::iterator p = this->elements_.begin();
- p != this->elements_.end();
- ++p)
- (*p)->set_section_addresses(symtab, layout, this->output_section_,
- subalign, dot_value, dot_alignment,
- &dot_section, &fill, &input_sections);
- gold_assert(input_sections.empty());
- if (vma_region != NULL)
- {
- // Update the VMA region being used by the section now that we know how
- // big it is. Use the current address in the region, rather than
- // start_address because that might have been aligned upwards and we
- // need to allow for the padding.
- Expression* addr = vma_region->get_current_address();
- uint64_t size = *dot_value - addr->eval(symtab, layout, false);
- vma_region->increment_offset(this->get_section_name(), size,
- symtab, layout);
- }
- // If the LMA region is different from the VMA region, then increment the
- // offset there as well. Note that we use the same "dot_value -
- // start_address" formula that is used in the load_address assignment below.
- if (lma_region != NULL && lma_region != vma_region)
- lma_region->increment_offset(this->get_section_name(),
- *dot_value - start_address,
- symtab, layout);
- // Compute the load address for the following section.
- if (this->output_section_ == NULL)
- *load_address = *dot_value;
- else if (this->load_address_ == NULL)
- {
- if (lma_region == NULL)
- *load_address = *dot_value;
- else
- *load_address =
- lma_region->get_current_address()->eval(symtab, layout, false);
- }
- else
- *load_address = (this->output_section_->load_address()
- + (*dot_value - start_address));
- if (this->output_section_ != NULL)
- {
- if (this->is_relro_)
- this->output_section_->set_is_relro();
- else
- this->output_section_->clear_is_relro();
- // If this is a NOLOAD section, keep dot and load address unchanged.
- if (this->output_section_->is_noload())
- {
- *dot_value = old_dot_value;
- *load_address = old_load_address;
- }
- }
- }
- // Check a constraint (ONLY_IF_RO, etc.) on an output section. If
- // this section is constrained, and the input sections do not match,
- // return the constraint, and set *POSD.
- Section_constraint
- Output_section_definition::check_constraint(Output_section_definition** posd)
- {
- switch (this->constraint_)
- {
- case CONSTRAINT_NONE:
- return CONSTRAINT_NONE;
- case CONSTRAINT_ONLY_IF_RO:
- if (this->output_section_ != NULL
- && (this->output_section_->flags() & elfcpp::SHF_WRITE) != 0)
- {
- *posd = this;
- return CONSTRAINT_ONLY_IF_RO;
- }
- return CONSTRAINT_NONE;
- case CONSTRAINT_ONLY_IF_RW:
- if (this->output_section_ != NULL
- && (this->output_section_->flags() & elfcpp::SHF_WRITE) == 0)
- {
- *posd = this;
- return CONSTRAINT_ONLY_IF_RW;
- }
- return CONSTRAINT_NONE;
- case CONSTRAINT_SPECIAL:
- if (this->output_section_ != NULL)
- gold_error(_("SPECIAL constraints are not implemented"));
- return CONSTRAINT_NONE;
- default:
- gold_unreachable();
- }
- }
- // See if this is the alternate output section for a constrained
- // output section. If it is, transfer the Output_section and return
- // true. Otherwise return false.
- bool
- Output_section_definition::alternate_constraint(
- Output_section_definition* posd,
- Section_constraint constraint)
- {
- if (this->name_ != posd->name_)
- return false;
- switch (constraint)
- {
- case CONSTRAINT_ONLY_IF_RO:
- if (this->constraint_ != CONSTRAINT_ONLY_IF_RW)
- return false;
- break;
- case CONSTRAINT_ONLY_IF_RW:
- if (this->constraint_ != CONSTRAINT_ONLY_IF_RO)
- return false;
- break;
- default:
- gold_unreachable();
- }
- // We have found the alternate constraint. We just need to move
- // over the Output_section. When constraints are used properly,
- // THIS should not have an output_section pointer, as all the input
- // sections should have matched the other definition.
- if (this->output_section_ != NULL)
- gold_error(_("mismatched definition for constrained sections"));
- this->output_section_ = posd->output_section_;
- posd->output_section_ = NULL;
- if (this->is_relro_)
- this->output_section_->set_is_relro();
- else
- this->output_section_->clear_is_relro();
- return true;
- }
- // Get the list of segments to use for an allocated section when using
- // a PHDRS clause.
- Output_section*
- Output_section_definition::allocate_to_segment(String_list** phdrs_list,
- bool* orphan)
- {
- // Update phdrs_list even if we don't have an output section. It
- // might be used by the following sections.
- if (this->phdrs_ != NULL)
- *phdrs_list = this->phdrs_;
- if (this->output_section_ == NULL)
- return NULL;
- if ((this->output_section_->flags() & elfcpp::SHF_ALLOC) == 0)
- return NULL;
- *orphan = false;
- return this->output_section_;
- }
- // Look for an output section by name and return the address, the load
- // address, the alignment, and the size. This is used when an
- // expression refers to an output section which was not actually
- // created. This returns true if the section was found, false
- // otherwise.
- bool
- Output_section_definition::get_output_section_info(const char* name,
- uint64_t* address,
- uint64_t* load_address,
- uint64_t* addralign,
- uint64_t* size) const
- {
- if (this->name_ != name)
- return false;
- if (this->output_section_ != NULL)
- {
- *address = this->output_section_->address();
- if (this->output_section_->has_load_address())
- *load_address = this->output_section_->load_address();
- else
- *load_address = *address;
- *addralign = this->output_section_->addralign();
- *size = this->output_section_->current_data_size();
- }
- else
- {
- *address = this->evaluated_address_;
- *load_address = this->evaluated_load_address_;
- *addralign = this->evaluated_addralign_;
- *size = 0;
- }
- return true;
- }
- // Print for debugging.
- void
- Output_section_definition::print(FILE* f) const
- {
- fprintf(f, " %s ", this->name_.c_str());
- if (this->address_ != NULL)
- {
- this->address_->print(f);
- fprintf(f, " ");
- }
- if (this->script_section_type_ != SCRIPT_SECTION_TYPE_NONE)
- fprintf(f, "(%s) ",
- this->script_section_type_name(this->script_section_type_));
- fprintf(f, ": ");
- if (this->load_address_ != NULL)
- {
- fprintf(f, "AT(");
- this->load_address_->print(f);
- fprintf(f, ") ");
- }
- if (this->align_ != NULL)
- {
- fprintf(f, "ALIGN(");
- this->align_->print(f);
- fprintf(f, ") ");
- }
- if (this->subalign_ != NULL)
- {
- fprintf(f, "SUBALIGN(");
- this->subalign_->print(f);
- fprintf(f, ") ");
- }
- fprintf(f, "{\n");
- for (Output_section_elements::const_iterator p = this->elements_.begin();
- p != this->elements_.end();
- ++p)
- (*p)->print(f);
- fprintf(f, " }");
- if (this->fill_ != NULL)
- {
- fprintf(f, " = ");
- this->fill_->print(f);
- }
- if (this->phdrs_ != NULL)
- {
- for (String_list::const_iterator p = this->phdrs_->begin();
- p != this->phdrs_->end();
- ++p)
- fprintf(f, " :%s", p->c_str());
- }
- fprintf(f, "\n");
- }
- Script_sections::Section_type
- Output_section_definition::section_type() const
- {
- switch (this->script_section_type_)
- {
- case SCRIPT_SECTION_TYPE_NONE:
- return Script_sections::ST_NONE;
- case SCRIPT_SECTION_TYPE_NOLOAD:
- return Script_sections::ST_NOLOAD;
- case SCRIPT_SECTION_TYPE_COPY:
- case SCRIPT_SECTION_TYPE_DSECT:
- case SCRIPT_SECTION_TYPE_INFO:
- case SCRIPT_SECTION_TYPE_OVERLAY:
- // There are not really support so we treat them as ST_NONE. The
- // parse should have issued errors for them already.
- return Script_sections::ST_NONE;
- default:
- gold_unreachable();
- }
- }
- // Return the name of a script section type.
- const char*
- Output_section_definition::script_section_type_name(
- Script_section_type script_section_type)
- {
- switch (script_section_type)
- {
- case SCRIPT_SECTION_TYPE_NONE:
- return "NONE";
- case SCRIPT_SECTION_TYPE_NOLOAD:
- return "NOLOAD";
- case SCRIPT_SECTION_TYPE_DSECT:
- return "DSECT";
- case SCRIPT_SECTION_TYPE_COPY:
- return "COPY";
- case SCRIPT_SECTION_TYPE_INFO:
- return "INFO";
- case SCRIPT_SECTION_TYPE_OVERLAY:
- return "OVERLAY";
- default:
- gold_unreachable();
- }
- }
- void
- Output_section_definition::set_memory_region(Memory_region* mr, bool set_vma)
- {
- gold_assert(mr != NULL);
- // Add the current section to the specified region's list.
- mr->add_section(this, set_vma);
- }
- // An output section created to hold orphaned input sections. These
- // do not actually appear in linker scripts. However, for convenience
- // when setting the output section addresses, we put a marker to these
- // sections in the appropriate place in the list of SECTIONS elements.
- class Orphan_output_section : public Sections_element
- {
- public:
- Orphan_output_section(Output_section* os)
- : os_(os)
- { }
- // Return whether the orphan output section is relro. We can just
- // check the output section because we always set the flag, if
- // needed, just after we create the Orphan_output_section.
- bool
- is_relro() const
- { return this->os_->is_relro(); }
- // Initialize OSP with an output section. This should have been
- // done already.
- void
- orphan_section_init(Orphan_section_placement*,
- Script_sections::Elements_iterator)
- { gold_unreachable(); }
- // Set section addresses.
- void
- set_section_addresses(Symbol_table*, Layout*, uint64_t*, uint64_t*,
- uint64_t*);
- // Get the list of segments to use for an allocated section when
- // using a PHDRS clause.
- Output_section*
- allocate_to_segment(String_list**, bool*);
- // Return the associated Output_section.
- Output_section*
- get_output_section() const
- { return this->os_; }
- // Print for debugging.
- void
- print(FILE* f) const
- {
- fprintf(f, " marker for orphaned output section %s\n",
- this->os_->name());
- }
- private:
- Output_section* os_;
- };
- // Set section addresses.
- void
- Orphan_output_section::set_section_addresses(Symbol_table*, Layout*,
- uint64_t* dot_value,
- uint64_t*,
- uint64_t* load_address)
- {
- typedef std::list<Output_section::Input_section> Input_section_list;
- bool have_load_address = *load_address != *dot_value;
- uint64_t address = *dot_value;
- address = align_address(address, this->os_->addralign());
- // If input section sorting is requested via --section-ordering-file or
- // linker plugins, then do it here. This is important because we want
- // any sorting specified in the linker scripts, which will be done after
- // this, to take precedence. The final order of input sections is then
- // guaranteed to be according to the linker script specification.
- if (this->os_ != NULL
- && this->os_->input_section_order_specified())
- this->os_->sort_attached_input_sections();
- // For a relocatable link, all orphan sections are put at
- // address 0. In general we expect all sections to be at
- // address 0 for a relocatable link, but we permit the linker
- // script to override that for specific output sections.
- if (parameters->options().relocatable())
- {
- address = 0;
- *load_address = 0;
- have_load_address = false;
- }
- if ((this->os_->flags() & elfcpp::SHF_ALLOC) != 0)
- {
- this->os_->set_address(address);
- if (have_load_address)
- this->os_->set_load_address(align_address(*load_address,
- this->os_->addralign()));
- }
- Input_section_list input_sections;
- address += this->os_->get_input_sections(address, "", &input_sections);
- for (Input_section_list::iterator p = input_sections.begin();
- p != input_sections.end();
- ++p)
- {
- uint64_t addralign = p->addralign();
- if (!p->is_input_section())
- p->output_section_data()->finalize_data_size();
- uint64_t size = p->data_size();
- address = align_address(address, addralign);
- this->os_->add_script_input_section(*p);
- address += size;
- }
- if (parameters->options().relocatable())
- {
- // For a relocatable link, reset DOT_VALUE to 0.
- *dot_value = 0;
- *load_address = 0;
- }
- else if (this->os_ == NULL
- || (this->os_->flags() & elfcpp::SHF_TLS) == 0
- || this->os_->type() != elfcpp::SHT_NOBITS)
- {
- // An SHF_TLS/SHT_NOBITS section does not take up any address space.
- if (!have_load_address)
- *load_address = address;
- else
- *load_address += address - *dot_value;
- *dot_value = address;
- }
- }
- // Get the list of segments to use for an allocated section when using
- // a PHDRS clause. If this is an allocated section, return the
- // Output_section. We don't change the list of segments.
- Output_section*
- Orphan_output_section::allocate_to_segment(String_list**, bool* orphan)
- {
- if ((this->os_->flags() & elfcpp::SHF_ALLOC) == 0)
- return NULL;
- *orphan = true;
- return this->os_;
- }
- // Class Phdrs_element. A program header from a PHDRS clause.
- class Phdrs_element
- {
- public:
- Phdrs_element(const char* name, size_t namelen, unsigned int type,
- bool includes_filehdr, bool includes_phdrs,
- bool is_flags_valid, unsigned int flags,
- Expression* load_address)
- : name_(name, namelen), type_(type), includes_filehdr_(includes_filehdr),
- includes_phdrs_(includes_phdrs), is_flags_valid_(is_flags_valid),
- flags_(flags), load_address_(load_address), load_address_value_(0),
- segment_(NULL)
- { }
- // Return the name of this segment.
- const std::string&
- name() const
- { return this->name_; }
- // Return the type of the segment.
- unsigned int
- type() const
- { return this->type_; }
- // Whether to include the file header.
- bool
- includes_filehdr() const
- { return this->includes_filehdr_; }
- // Whether to include the program headers.
- bool
- includes_phdrs() const
- { return this->includes_phdrs_; }
- // Return whether there is a load address.
- bool
- has_load_address() const
- { return this->load_address_ != NULL; }
- // Evaluate the load address expression if there is one.
- void
- eval_load_address(Symbol_table* symtab, Layout* layout)
- {
- if (this->load_address_ != NULL)
- this->load_address_value_ = this->load_address_->eval(symtab, layout,
- true);
- }
- // Return the load address.
- uint64_t
- load_address() const
- {
- gold_assert(this->load_address_ != NULL);
- return this->load_address_value_;
- }
- // Create the segment.
- Output_segment*
- create_segment(Layout* layout)
- {
- this->segment_ = layout->make_output_segment(this->type_, this->flags_);
- return this->segment_;
- }
- // Return the segment.
- Output_segment*
- segment()
- { return this->segment_; }
- // Release the segment.
- void
- release_segment()
- { this->segment_ = NULL; }
- // Set the segment flags if appropriate.
- void
- set_flags_if_valid()
- {
- if (this->is_flags_valid_)
- this->segment_->set_flags(this->flags_);
- }
- // Print for debugging.
- void
- print(FILE*) const;
- private:
- // The name used in the script.
- std::string name_;
- // The type of the segment (PT_LOAD, etc.).
- unsigned int type_;
- // Whether this segment includes the file header.
- bool includes_filehdr_;
- // Whether this segment includes the section headers.
- bool includes_phdrs_;
- // Whether the flags were explicitly specified.
- bool is_flags_valid_;
- // The flags for this segment (PF_R, etc.) if specified.
- unsigned int flags_;
- // The expression for the load address for this segment. This may
- // be NULL.
- Expression* load_address_;
- // The actual load address from evaluating the expression.
- uint64_t load_address_value_;
- // The segment itself.
- Output_segment* segment_;
- };
- // Print for debugging.
- void
- Phdrs_element::print(FILE* f) const
- {
- fprintf(f, " %s 0x%x", this->name_.c_str(), this->type_);
- if (this->includes_filehdr_)
- fprintf(f, " FILEHDR");
- if (this->includes_phdrs_)
- fprintf(f, " PHDRS");
- if (this->is_flags_valid_)
- fprintf(f, " FLAGS(%u)", this->flags_);
- if (this->load_address_ != NULL)
- {
- fprintf(f, " AT(");
- this->load_address_->print(f);
- fprintf(f, ")");
- }
- fprintf(f, ";\n");
- }
- // Add a memory region.
- void
- Script_sections::add_memory_region(const char* name, size_t namelen,
- unsigned int attributes,
- Expression* start, Expression* length)
- {
- if (this->memory_regions_ == NULL)
- this->memory_regions_ = new Memory_regions();
- else if (this->find_memory_region(name, namelen))
- {
- gold_error(_("region '%.*s' already defined"), static_cast<int>(namelen),
- name);
- // FIXME: Add a GOLD extension to allow multiple regions with the same
- // name. This would amount to a single region covering disjoint blocks
- // of memory, which is useful for embedded devices.
- }
- // FIXME: Check the length and start values. Currently we allow
- // non-constant expressions for these values, whereas LD does not.
- // FIXME: Add a GOLD extension to allow NEGATIVE LENGTHS. This would
- // describe a region that packs from the end address going down, rather
- // than the start address going up. This would be useful for embedded
- // devices.
- this->memory_regions_->push_back(new Memory_region(name, namelen, attributes,
- start, length));
- }
- // Find a memory region.
- Memory_region*
- Script_sections::find_memory_region(const char* name, size_t namelen)
- {
- if (this->memory_regions_ == NULL)
- return NULL;
- for (Memory_regions::const_iterator m = this->memory_regions_->begin();
- m != this->memory_regions_->end();
- ++m)
- if ((*m)->name_match(name, namelen))
- return *m;
- return NULL;
- }
- // Find a memory region's origin.
- Expression*
- Script_sections::find_memory_region_origin(const char* name, size_t namelen)
- {
- Memory_region* mr = find_memory_region(name, namelen);
- if (mr == NULL)
- return NULL;
- return mr->start_address();
- }
- // Find a memory region's length.
- Expression*
- Script_sections::find_memory_region_length(const char* name, size_t namelen)
- {
- Memory_region* mr = find_memory_region(name, namelen);
- if (mr == NULL)
- return NULL;
- return mr->length();
- }
- // Set the memory region to use for the current section.
- void
- Script_sections::set_memory_region(Memory_region* mr, bool set_vma)
- {
- gold_assert(!this->sections_elements_->empty());
- this->sections_elements_->back()->set_memory_region(mr, set_vma);
- }
- // Class Script_sections.
- Script_sections::Script_sections()
- : saw_sections_clause_(false),
- in_sections_clause_(false),
- sections_elements_(NULL),
- output_section_(NULL),
- memory_regions_(NULL),
- phdrs_elements_(NULL),
- orphan_section_placement_(NULL),
- data_segment_align_start_(),
- saw_data_segment_align_(false),
- saw_relro_end_(false),
- saw_segment_start_expression_(false),
- segments_created_(false)
- {
- }
- // Start a SECTIONS clause.
- void
- Script_sections::start_sections()
- {
- gold_assert(!this->in_sections_clause_ && this->output_section_ == NULL);
- this->saw_sections_clause_ = true;
- this->in_sections_clause_ = true;
- if (this->sections_elements_ == NULL)
- this->sections_elements_ = new Sections_elements;
- }
- // Finish a SECTIONS clause.
- void
- Script_sections::finish_sections()
- {
- gold_assert(this->in_sections_clause_ && this->output_section_ == NULL);
- this->in_sections_clause_ = false;
- }
- // Add a symbol to be defined.
- void
- Script_sections::add_symbol_assignment(const char* name, size_t length,
- Expression* val, bool provide,
- bool hidden)
- {
- if (this->output_section_ != NULL)
- this->output_section_->add_symbol_assignment(name, length, val,
- provide, hidden);
- else
- {
- Sections_element* p = new Sections_element_assignment(name, length,
- val, provide,
- hidden);
- this->sections_elements_->push_back(p);
- }
- }
- // Add an assignment to the special dot symbol.
- void
- Script_sections::add_dot_assignment(Expression* val)
- {
- if (this->output_section_ != NULL)
- this->output_section_->add_dot_assignment(val);
- else
- {
- // The GNU linker permits assignments to . to appears outside of
- // a SECTIONS clause, and treats it as appearing inside, so
- // sections_elements_ may be NULL here.
- if (this->sections_elements_ == NULL)
- {
- this->sections_elements_ = new Sections_elements;
- this->saw_sections_clause_ = true;
- }
- Sections_element* p = new Sections_element_dot_assignment(val);
- this->sections_elements_->push_back(p);
- }
- }
- // Add an assertion.
- void
- Script_sections::add_assertion(Expression* check, const char* message,
- size_t messagelen)
- {
- if (this->output_section_ != NULL)
- this->output_section_->add_assertion(check, message, messagelen);
- else
- {
- Sections_element* p = new Sections_element_assertion(check, message,
- messagelen);
- this->sections_elements_->push_back(p);
- }
- }
- // Start processing entries for an output section.
- void
- Script_sections::start_output_section(
- const char* name,
- size_t namelen,
- const Parser_output_section_header* header)
- {
- Output_section_definition* posd = new Output_section_definition(name,
- namelen,
- header);
- this->sections_elements_->push_back(posd);
- gold_assert(this->output_section_ == NULL);
- this->output_section_ = posd;
- }
- // Stop processing entries for an output section.
- void
- Script_sections::finish_output_section(
- const Parser_output_section_trailer* trailer)
- {
- gold_assert(this->output_section_ != NULL);
- this->output_section_->finish(trailer);
- this->output_section_ = NULL;
- }
- // Add a data item to the current output section.
- void
- Script_sections::add_data(int size, bool is_signed, Expression* val)
- {
- gold_assert(this->output_section_ != NULL);
- this->output_section_->add_data(size, is_signed, val);
- }
- // Add a fill value setting to the current output section.
- void
- Script_sections::add_fill(Expression* val)
- {
- gold_assert(this->output_section_ != NULL);
- this->output_section_->add_fill(val);
- }
- // Add an input section specification to the current output section.
- void
- Script_sections::add_input_section(const Input_section_spec* spec, bool keep)
- {
- gold_assert(this->output_section_ != NULL);
- this->output_section_->add_input_section(spec, keep);
- }
- // This is called when we see DATA_SEGMENT_ALIGN. It means that any
- // subsequent output sections may be relro.
- void
- Script_sections::data_segment_align()
- {
- if (this->saw_data_segment_align_)
- gold_error(_("DATA_SEGMENT_ALIGN may only appear once in a linker script"));
- gold_assert(!this->sections_elements_->empty());
- Sections_elements::iterator p = this->sections_elements_->end();
- --p;
- this->data_segment_align_start_ = p;
- this->saw_data_segment_align_ = true;
- }
- // This is called when we see DATA_SEGMENT_RELRO_END. It means that
- // any output sections seen since DATA_SEGMENT_ALIGN are relro.
- void
- Script_sections::data_segment_relro_end()
- {
- if (this->saw_relro_end_)
- gold_error(_("DATA_SEGMENT_RELRO_END may only appear once "
- "in a linker script"));
- this->saw_relro_end_ = true;
- if (!this->saw_data_segment_align_)
- gold_error(_("DATA_SEGMENT_RELRO_END must follow DATA_SEGMENT_ALIGN"));
- else
- {
- Sections_elements::iterator p = this->data_segment_align_start_;
- for (++p; p != this->sections_elements_->end(); ++p)
- (*p)->set_is_relro();
- }
- }
- // Create any required sections.
- void
- Script_sections::create_sections(Layout* layout)
- {
- if (!this->saw_sections_clause_)
- return;
- for (Sections_elements::iterator p = this->sections_elements_->begin();
- p != this->sections_elements_->end();
- ++p)
- (*p)->create_sections(layout);
- }
- // Add any symbols we are defining to the symbol table.
- void
- Script_sections::add_symbols_to_table(Symbol_table* symtab)
- {
- if (!this->saw_sections_clause_)
- return;
- for (Sections_elements::iterator p = this->sections_elements_->begin();
- p != this->sections_elements_->end();
- ++p)
- (*p)->add_symbols_to_table(symtab);
- }
- // Finalize symbols and check assertions.
- void
- Script_sections::finalize_symbols(Symbol_table* symtab, const Layout* layout)
- {
- if (!this->saw_sections_clause_)
- return;
- uint64_t dot_value = 0;
- for (Sections_elements::iterator p = this->sections_elements_->begin();
- p != this->sections_elements_->end();
- ++p)
- (*p)->finalize_symbols(symtab, layout, &dot_value);
- }
- // Return the name of the output section to use for an input file name
- // and section name.
- const char*
- Script_sections::output_section_name(
- const char* file_name,
- const char* section_name,
- Output_section*** output_section_slot,
- Script_sections::Section_type* psection_type,
- bool* keep,
- bool is_input_section)
- {
- for (Sections_elements::const_iterator p = this->sections_elements_->begin();
- p != this->sections_elements_->end();
- ++p)
- {
- const char* ret = (*p)->output_section_name(file_name, section_name,
- output_section_slot,
- psection_type, keep,
- is_input_section);
- if (ret != NULL)
- {
- // The special name /DISCARD/ means that the input section
- // should be discarded.
- if (strcmp(ret, "/DISCARD/") == 0)
- {
- *output_section_slot = NULL;
- *psection_type = Script_sections::ST_NONE;
- return NULL;
- }
- return ret;
- }
- }
- // We have an orphan section.
- *output_section_slot = NULL;
- *psection_type = Script_sections::ST_NONE;
- *keep = false;
- General_options::Orphan_handling orphan_handling =
- parameters->options().orphan_handling_enum();
- if (orphan_handling == General_options::ORPHAN_DISCARD)
- return NULL;
- if (orphan_handling == General_options::ORPHAN_ERROR)
- {
- if (file_name == NULL)
- gold_error(_("unplaced orphan section '%s'"), section_name);
- else
- gold_error(_("unplaced orphan section '%s' from '%s'"),
- section_name, file_name);
- return NULL;
- }
- if (orphan_handling == General_options::ORPHAN_WARN)
- {
- if (file_name == NULL)
- gold_warning(_("orphan section '%s' is being placed in section '%s'"),
- section_name, section_name);
- else
- gold_warning(_("orphan section '%s' from '%s' is being placed "
- "in section '%s'"),
- section_name, file_name, section_name);
- }
- // If we couldn't find a mapping for the name, the output section
- // gets the name of the input section.
- return section_name;
- }
- // Place a marker for an orphan output section into the SECTIONS
- // clause.
- void
- Script_sections::place_orphan(Output_section* os)
- {
- Orphan_section_placement* osp = this->orphan_section_placement_;
- if (osp == NULL)
- {
- // Initialize the Orphan_section_placement structure.
- osp = new Orphan_section_placement();
- for (Sections_elements::iterator p = this->sections_elements_->begin();
- p != this->sections_elements_->end();
- ++p)
- (*p)->orphan_section_init(osp, p);
- gold_assert(!this->sections_elements_->empty());
- Sections_elements::iterator last = this->sections_elements_->end();
- --last;
- osp->last_init(last);
- this->orphan_section_placement_ = osp;
- }
- Orphan_output_section* orphan = new Orphan_output_section(os);
- // Look for where to put ORPHAN.
- Sections_elements::iterator* where;
- if (osp->find_place(os, &where))
- {
- if ((**where)->is_relro())
- os->set_is_relro();
- else
- os->clear_is_relro();
- // We want to insert ORPHAN after *WHERE, and then update *WHERE
- // so that the next one goes after this one.
- Sections_elements::iterator p = *where;
- gold_assert(p != this->sections_elements_->end());
- ++p;
- *where = this->sections_elements_->insert(p, orphan);
- }
- else
- {
- os->clear_is_relro();
- // We don't have a place to put this orphan section. Put it,
- // and all other sections like it, at the end, but before the
- // sections which always come at the end.
- Sections_elements::iterator last = osp->last_place();
- *where = this->sections_elements_->insert(last, orphan);
- }
- if ((os->flags() & elfcpp::SHF_ALLOC) != 0)
- osp->update_last_alloc(*where);
- }
- // Set the addresses of all the output sections. Walk through all the
- // elements, tracking the dot symbol. Apply assignments which set
- // absolute symbol values, in case they are used when setting dot.
- // Fill in data statement values. As we find output sections, set the
- // address, set the address of all associated input sections, and
- // update dot. Return the segment which should hold the file header
- // and segment headers, if any.
- Output_segment*
- Script_sections::set_section_addresses(Symbol_table* symtab, Layout* layout)
- {
- gold_assert(this->saw_sections_clause_);
- // Implement ONLY_IF_RO/ONLY_IF_RW constraints. These are a pain
- // for our representation.
- for (Sections_elements::iterator p = this->sections_elements_->begin();
- p != this->sections_elements_->end();
- ++p)
- {
- Output_section_definition* posd;
- Section_constraint failed_constraint = (*p)->check_constraint(&posd);
- if (failed_constraint != CONSTRAINT_NONE)
- {
- Sections_elements::iterator q;
- for (q = this->sections_elements_->begin();
- q != this->sections_elements_->end();
- ++q)
- {
- if (q != p)
- {
- if ((*q)->alternate_constraint(posd, failed_constraint))
- break;
- }
- }
- if (q == this->sections_elements_->end())
- gold_error(_("no matching section constraint"));
- }
- }
- // Force the alignment of the first TLS section to be the maximum
- // alignment of all TLS sections.
- Output_section* first_tls = NULL;
- uint64_t tls_align = 0;
- for (Sections_elements::const_iterator p = this->sections_elements_->begin();
- p != this->sections_elements_->end();
- ++p)
- {
- Output_section* os = (*p)->get_output_section();
- if (os != NULL && (os->flags() & elfcpp::SHF_TLS) != 0)
- {
- if (first_tls == NULL)
- first_tls = os;
- if (os->addralign() > tls_align)
- tls_align = os->addralign();
- }
- }
- if (first_tls != NULL)
- first_tls->set_addralign(tls_align);
- // For a relocatable link, we implicitly set dot to zero.
- uint64_t dot_value = 0;
- uint64_t dot_alignment = 0;
- uint64_t load_address = 0;
- // Check to see if we want to use any of -Ttext, -Tdata and -Tbss options
- // to set section addresses. If the script has any SEGMENT_START
- // expression, we do not set the section addresses.
- bool use_tsection_options =
- (!this->saw_segment_start_expression_
- && (parameters->options().user_set_Ttext()
- || parameters->options().user_set_Tdata()
- || parameters->options().user_set_Tbss()));
- for (Sections_elements::iterator p = this->sections_elements_->begin();
- p != this->sections_elements_->end();
- ++p)
- {
- Output_section* os = (*p)->get_output_section();
- // Handle -Ttext, -Tdata and -Tbss options. We do this by looking for
- // the special sections by names and doing dot assignments.
- if (use_tsection_options
- && os != NULL
- && (os->flags() & elfcpp::SHF_ALLOC) != 0)
- {
- uint64_t new_dot_value = dot_value;
- if (parameters->options().user_set_Ttext()
- && strcmp(os->name(), ".text") == 0)
- new_dot_value = parameters->options().Ttext();
- else if (parameters->options().user_set_Tdata()
- && strcmp(os->name(), ".data") == 0)
- new_dot_value = parameters->options().Tdata();
- else if (parameters->options().user_set_Tbss()
- && strcmp(os->name(), ".bss") == 0)
- new_dot_value = parameters->options().Tbss();
- // Update dot and load address if necessary.
- if (new_dot_value < dot_value)
- gold_error(_("dot may not move backward"));
- else if (new_dot_value != dot_value)
- {
- dot_value = new_dot_value;
- load_address = new_dot_value;
- }
- }
- (*p)->set_section_addresses(symtab, layout, &dot_value, &dot_alignment,
- &load_address);
- }
- if (this->phdrs_elements_ != NULL)
- {
- for (Phdrs_elements::iterator p = this->phdrs_elements_->begin();
- p != this->phdrs_elements_->end();
- ++p)
- (*p)->eval_load_address(symtab, layout);
- }
- return this->create_segments(layout, dot_alignment);
- }
- // Sort the sections in order to put them into segments.
- class Sort_output_sections
- {
- public:
- Sort_output_sections(const Script_sections::Sections_elements* elements)
- : elements_(elements)
- { }
- bool
- operator()(const Output_section* os1, const Output_section* os2) const;
- private:
- int
- script_compare(const Output_section* os1, const Output_section* os2) const;
- private:
- const Script_sections::Sections_elements* elements_;
- };
- bool
- Sort_output_sections::operator()(const Output_section* os1,
- const Output_section* os2) const
- {
- // Sort first by the load address.
- uint64_t lma1 = (os1->has_load_address()
- ? os1->load_address()
- : os1->address());
- uint64_t lma2 = (os2->has_load_address()
- ? os2->load_address()
- : os2->address());
- if (lma1 != lma2)
- return lma1 < lma2;
- // Then sort by the virtual address.
- if (os1->address() != os2->address())
- return os1->address() < os2->address();
- // If the linker script says which of these sections is first, go
- // with what it says.
- int i = this->script_compare(os1, os2);
- if (i != 0)
- return i < 0;
- // Sort PROGBITS before NOBITS.
- bool nobits1 = os1->type() == elfcpp::SHT_NOBITS;
- bool nobits2 = os2->type() == elfcpp::SHT_NOBITS;
- if (nobits1 != nobits2)
- return nobits2;
- // Sort PROGBITS TLS sections to the end, NOBITS TLS sections to the
- // beginning.
- bool tls1 = (os1->flags() & elfcpp::SHF_TLS) != 0;
- bool tls2 = (os2->flags() & elfcpp::SHF_TLS) != 0;
- if (tls1 != tls2)
- return nobits1 ? tls1 : tls2;
- // Sort non-NOLOAD before NOLOAD.
- if (os1->is_noload() && !os2->is_noload())
- return true;
- if (!os1->is_noload() && os2->is_noload())
- return true;
- // The sections seem practically identical. Sort by name to get a
- // stable sort.
- return os1->name() < os2->name();
- }
- // Return -1 if OS1 comes before OS2 in ELEMENTS_, 1 if comes after, 0
- // if either OS1 or OS2 is not mentioned. This ensures that we keep
- // empty sections in the order in which they appear in a linker
- // script.
- int
- Sort_output_sections::script_compare(const Output_section* os1,
- const Output_section* os2) const
- {
- if (this->elements_ == NULL)
- return 0;
- bool found_os1 = false;
- bool found_os2 = false;
- for (Script_sections::Sections_elements::const_iterator
- p = this->elements_->begin();
- p != this->elements_->end();
- ++p)
- {
- if (os2 == (*p)->get_output_section())
- {
- if (found_os1)
- return -1;
- found_os2 = true;
- }
- else if (os1 == (*p)->get_output_section())
- {
- if (found_os2)
- return 1;
- found_os1 = true;
- }
- }
- return 0;
- }
- // Return whether OS is a BSS section. This is a SHT_NOBITS section.
- // We treat a section with the SHF_TLS flag set as taking up space
- // even if it is SHT_NOBITS (this is true of .tbss), as we allocate
- // space for them in the file.
- bool
- Script_sections::is_bss_section(const Output_section* os)
- {
- return (os->type() == elfcpp::SHT_NOBITS
- && (os->flags() & elfcpp::SHF_TLS) == 0);
- }
- // Return the size taken by the file header and the program headers.
- size_t
- Script_sections::total_header_size(Layout* layout) const
- {
- size_t segment_count = layout->segment_count();
- size_t file_header_size;
- size_t segment_headers_size;
- if (parameters->target().get_size() == 32)
- {
- file_header_size = elfcpp::Elf_sizes<32>::ehdr_size;
- segment_headers_size = segment_count * elfcpp::Elf_sizes<32>::phdr_size;
- }
- else if (parameters->target().get_size() == 64)
- {
- file_header_size = elfcpp::Elf_sizes<64>::ehdr_size;
- segment_headers_size = segment_count * elfcpp::Elf_sizes<64>::phdr_size;
- }
- else
- gold_unreachable();
- return file_header_size + segment_headers_size;
- }
- // Return the amount we have to subtract from the LMA to accommodate
- // headers of the given size. The complication is that the file
- // header have to be at the start of a page, as otherwise it will not
- // be at the start of the file.
- uint64_t
- Script_sections::header_size_adjustment(uint64_t lma,
- size_t sizeof_headers) const
- {
- const uint64_t abi_pagesize = parameters->target().abi_pagesize();
- uint64_t hdr_lma = lma - sizeof_headers;
- hdr_lma &= ~(abi_pagesize - 1);
- return lma - hdr_lma;
- }
- // Create the PT_LOAD segments when using a SECTIONS clause. Returns
- // the segment which should hold the file header and segment headers,
- // if any.
- Output_segment*
- Script_sections::create_segments(Layout* layout, uint64_t dot_alignment)
- {
- gold_assert(this->saw_sections_clause_);
- if (parameters->options().relocatable())
- return NULL;
- if (this->saw_phdrs_clause())
- return create_segments_from_phdrs_clause(layout, dot_alignment);
- Layout::Section_list sections;
- layout->get_allocated_sections(§ions);
- // Sort the sections by address.
- std::stable_sort(sections.begin(), sections.end(),
- Sort_output_sections(this->sections_elements_));
- this->create_note_and_tls_segments(layout, §ions);
- // Walk through the sections adding them to PT_LOAD segments.
- const uint64_t abi_pagesize = parameters->target().abi_pagesize();
- Output_segment* first_seg = NULL;
- Output_segment* current_seg = NULL;
- bool is_current_seg_readonly = true;
- uint64_t last_vma = 0;
- uint64_t last_lma = 0;
- uint64_t last_size = 0;
- bool in_bss = false;
- for (Layout::Section_list::iterator p = sections.begin();
- p != sections.end();
- ++p)
- {
- const uint64_t vma = (*p)->address();
- const uint64_t lma = ((*p)->has_load_address()
- ? (*p)->load_address()
- : vma);
- const uint64_t size = (*p)->current_data_size();
- bool need_new_segment;
- if (current_seg == NULL)
- need_new_segment = true;
- else if (lma - vma != last_lma - last_vma)
- {
- // This section has a different LMA relationship than the
- // last one; we need a new segment.
- need_new_segment = true;
- }
- else if (align_address(last_lma + last_size, abi_pagesize)
- < align_address(lma, abi_pagesize))
- {
- // Putting this section in the segment would require
- // skipping a page.
- need_new_segment = true;
- }
- else if (in_bss && !is_bss_section(*p))
- {
- // A non-BSS section can not follow a BSS section in the
- // same segment.
- need_new_segment = true;
- }
- else if (is_current_seg_readonly
- && ((*p)->flags() & elfcpp::SHF_WRITE) != 0
- && !parameters->options().omagic())
- {
- // Don't put a writable section in the same segment as a
- // non-writable section.
- need_new_segment = true;
- }
- else
- {
- // Otherwise, reuse the existing segment.
- need_new_segment = false;
- }
- elfcpp::Elf_Word seg_flags =
- Layout::section_flags_to_segment((*p)->flags());
- if (need_new_segment)
- {
- current_seg = layout->make_output_segment(elfcpp::PT_LOAD,
- seg_flags);
- current_seg->set_addresses(vma, lma);
- current_seg->set_minimum_p_align(dot_alignment);
- if (first_seg == NULL)
- first_seg = current_seg;
- is_current_seg_readonly = true;
- in_bss = false;
- }
- current_seg->add_output_section_to_load(layout, *p, seg_flags);
- if (((*p)->flags() & elfcpp::SHF_WRITE) != 0)
- is_current_seg_readonly = false;
- if (is_bss_section(*p) && size > 0)
- in_bss = true;
- last_vma = vma;
- last_lma = lma;
- last_size = size;
- }
- // An ELF program should work even if the program headers are not in
- // a PT_LOAD segment. However, it appears that the Linux kernel
- // does not set the AT_PHDR auxiliary entry in that case. It sets
- // the load address to p_vaddr - p_offset of the first PT_LOAD
- // segment. It then sets AT_PHDR to the load address plus the
- // offset to the program headers, e_phoff in the file header. This
- // fails when the program headers appear in the file before the
- // first PT_LOAD segment. Therefore, we always create a PT_LOAD
- // segment to hold the file header and the program headers. This is
- // effectively what the GNU linker does, and it is slightly more
- // efficient in any case. We try to use the first PT_LOAD segment
- // if we can, otherwise we make a new one.
- if (first_seg == NULL)
- return NULL;
- // -n or -N mean that the program is not demand paged and there is
- // no need to put the program headers in a PT_LOAD segment.
- if (parameters->options().nmagic() || parameters->options().omagic())
- return NULL;
- size_t sizeof_headers = this->total_header_size(layout);
- uint64_t vma = first_seg->vaddr();
- uint64_t lma = first_seg->paddr();
- uint64_t subtract = this->header_size_adjustment(lma, sizeof_headers);
- if ((lma & (abi_pagesize - 1)) >= sizeof_headers)
- {
- first_seg->set_addresses(vma - subtract, lma - subtract);
- return first_seg;
- }
- // If there is no room to squeeze in the headers, then punt. The
- // resulting executable probably won't run on GNU/Linux, but we
- // trust that the user knows what they are doing.
- if (lma < subtract || vma < subtract)
- return NULL;
- // If memory regions have been specified and the address range
- // we are about to use is not contained within any region then
- // issue a warning message about the segment we are going to
- // create. It will be outside of any region and so possibly
- // using non-existent or protected memory. We test LMA rather
- // than VMA since we assume that the headers will never be
- // relocated.
- if (this->memory_regions_ != NULL
- && !this->block_in_region (NULL, layout, lma - subtract, subtract))
- gold_warning(_("creating a segment to contain the file and program"
- " headers outside of any MEMORY region"));
- Output_segment* load_seg = layout->make_output_segment(elfcpp::PT_LOAD,
- elfcpp::PF_R);
- load_seg->set_addresses(vma - subtract, lma - subtract);
- return load_seg;
- }
- // Create a PT_NOTE segment for each SHT_NOTE section and a PT_TLS
- // segment if there are any SHT_TLS sections.
- void
- Script_sections::create_note_and_tls_segments(
- Layout* layout,
- const Layout::Section_list* sections)
- {
- gold_assert(!this->saw_phdrs_clause());
- bool saw_tls = false;
- for (Layout::Section_list::const_iterator p = sections->begin();
- p != sections->end();
- ++p)
- {
- if ((*p)->type() == elfcpp::SHT_NOTE)
- {
- elfcpp::Elf_Word seg_flags =
- Layout::section_flags_to_segment((*p)->flags());
- Output_segment* oseg = layout->make_output_segment(elfcpp::PT_NOTE,
- seg_flags);
- oseg->add_output_section_to_nonload(*p, seg_flags);
- // Incorporate any subsequent SHT_NOTE sections, in the
- // hopes that the script is sensible.
- Layout::Section_list::const_iterator pnext = p + 1;
- while (pnext != sections->end()
- && (*pnext)->type() == elfcpp::SHT_NOTE)
- {
- seg_flags = Layout::section_flags_to_segment((*pnext)->flags());
- oseg->add_output_section_to_nonload(*pnext, seg_flags);
- p = pnext;
- ++pnext;
- }
- }
- if (((*p)->flags() & elfcpp::SHF_TLS) != 0)
- {
- if (saw_tls)
- gold_error(_("TLS sections are not adjacent"));
- elfcpp::Elf_Word seg_flags =
- Layout::section_flags_to_segment((*p)->flags());
- Output_segment* oseg = layout->make_output_segment(elfcpp::PT_TLS,
- seg_flags);
- oseg->add_output_section_to_nonload(*p, seg_flags);
- Layout::Section_list::const_iterator pnext = p + 1;
- while (pnext != sections->end()
- && ((*pnext)->flags() & elfcpp::SHF_TLS) != 0)
- {
- seg_flags = Layout::section_flags_to_segment((*pnext)->flags());
- oseg->add_output_section_to_nonload(*pnext, seg_flags);
- p = pnext;
- ++pnext;
- }
- saw_tls = true;
- }
- // If we see a section named .interp then put the .interp section
- // in a PT_INTERP segment.
- // This is for GNU ld compatibility.
- if (strcmp((*p)->name(), ".interp") == 0)
- {
- elfcpp::Elf_Word seg_flags =
- Layout::section_flags_to_segment((*p)->flags());
- Output_segment* oseg = layout->make_output_segment(elfcpp::PT_INTERP,
- seg_flags);
- oseg->add_output_section_to_nonload(*p, seg_flags);
- }
- }
- this->segments_created_ = true;
- }
- // Add a program header. The PHDRS clause is syntactically distinct
- // from the SECTIONS clause, but we implement it with the SECTIONS
- // support because PHDRS is useless if there is no SECTIONS clause.
- void
- Script_sections::add_phdr(const char* name, size_t namelen, unsigned int type,
- bool includes_filehdr, bool includes_phdrs,
- bool is_flags_valid, unsigned int flags,
- Expression* load_address)
- {
- if (this->phdrs_elements_ == NULL)
- this->phdrs_elements_ = new Phdrs_elements();
- this->phdrs_elements_->push_back(new Phdrs_element(name, namelen, type,
- includes_filehdr,
- includes_phdrs,
- is_flags_valid, flags,
- load_address));
- }
- // Return the number of segments we expect to create based on the
- // SECTIONS clause. This is used to implement SIZEOF_HEADERS.
- size_t
- Script_sections::expected_segment_count(const Layout* layout) const
- {
- // If we've already created the segments, we won't be adding any more.
- if (this->segments_created_)
- return 0;
- if (this->saw_phdrs_clause())
- return this->phdrs_elements_->size();
- Layout::Section_list sections;
- layout->get_allocated_sections(§ions);
- // We assume that we will need two PT_LOAD segments.
- size_t ret = 2;
- bool saw_note = false;
- bool saw_tls = false;
- bool saw_interp = false;
- for (Layout::Section_list::const_iterator p = sections.begin();
- p != sections.end();
- ++p)
- {
- if ((*p)->type() == elfcpp::SHT_NOTE)
- {
- // Assume that all note sections will fit into a single
- // PT_NOTE segment.
- if (!saw_note)
- {
- ++ret;
- saw_note = true;
- }
- }
- else if (((*p)->flags() & elfcpp::SHF_TLS) != 0)
- {
- // There can only be one PT_TLS segment.
- if (!saw_tls)
- {
- ++ret;
- saw_tls = true;
- }
- }
- else if (strcmp((*p)->name(), ".interp") == 0)
- {
- // There can only be one PT_INTERP segment.
- if (!saw_interp)
- {
- ++ret;
- saw_interp = true;
- }
- }
- }
- return ret;
- }
- // Create the segments from a PHDRS clause. Return the segment which
- // should hold the file header and program headers, if any.
- Output_segment*
- Script_sections::create_segments_from_phdrs_clause(Layout* layout,
- uint64_t dot_alignment)
- {
- this->attach_sections_using_phdrs_clause(layout);
- return this->set_phdrs_clause_addresses(layout, dot_alignment);
- }
- // Create the segments from the PHDRS clause, and put the output
- // sections in them.
- void
- Script_sections::attach_sections_using_phdrs_clause(Layout* layout)
- {
- typedef std::map<std::string, Output_segment*> Name_to_segment;
- Name_to_segment name_to_segment;
- for (Phdrs_elements::const_iterator p = this->phdrs_elements_->begin();
- p != this->phdrs_elements_->end();
- ++p)
- name_to_segment[(*p)->name()] = (*p)->create_segment(layout);
- this->segments_created_ = true;
- // Walk through the output sections and attach them to segments.
- // Output sections in the script which do not list segments are
- // attached to the same set of segments as the immediately preceding
- // output section.
- String_list* phdr_names = NULL;
- bool load_segments_only = false;
- for (Sections_elements::const_iterator p = this->sections_elements_->begin();
- p != this->sections_elements_->end();
- ++p)
- {
- bool is_orphan;
- String_list* old_phdr_names = phdr_names;
- Output_section* os = (*p)->allocate_to_segment(&phdr_names, &is_orphan);
- if (os == NULL)
- continue;
- elfcpp::Elf_Word seg_flags =
- Layout::section_flags_to_segment(os->flags());
- if (phdr_names == NULL)
- {
- // Don't worry about empty orphan sections.
- if (is_orphan && os->current_data_size() > 0)
- gold_error(_("allocated section %s not in any segment"),
- os->name());
- // To avoid later crashes drop this section into the first
- // PT_LOAD segment.
- for (Phdrs_elements::const_iterator ppe =
- this->phdrs_elements_->begin();
- ppe != this->phdrs_elements_->end();
- ++ppe)
- {
- Output_segment* oseg = (*ppe)->segment();
- if (oseg->type() == elfcpp::PT_LOAD)
- {
- oseg->add_output_section_to_load(layout, os, seg_flags);
- break;
- }
- }
- continue;
- }
- // We see a list of segments names. Disable PT_LOAD segment only
- // filtering.
- if (old_phdr_names != phdr_names)
- load_segments_only = false;
- // If this is an orphan section--one that was not explicitly
- // mentioned in the linker script--then it should not inherit
- // any segment type other than PT_LOAD. Otherwise, e.g., the
- // PT_INTERP segment will pick up following orphan sections,
- // which does not make sense. If this is not an orphan section,
- // we trust the linker script.
- if (is_orphan)
- {
- // Enable PT_LOAD segments only filtering until we see another
- // list of segment names.
- load_segments_only = true;
- }
- bool in_load_segment = false;
- for (String_list::const_iterator q = phdr_names->begin();
- q != phdr_names->end();
- ++q)
- {
- Name_to_segment::const_iterator r = name_to_segment.find(*q);
- if (r == name_to_segment.end())
- gold_error(_("no segment %s"), q->c_str());
- else
- {
- if (load_segments_only
- && r->second->type() != elfcpp::PT_LOAD)
- continue;
- if (r->second->type() != elfcpp::PT_LOAD)
- r->second->add_output_section_to_nonload(os, seg_flags);
- else
- {
- r->second->add_output_section_to_load(layout, os, seg_flags);
- if (in_load_segment)
- gold_error(_("section in two PT_LOAD segments"));
- in_load_segment = true;
- }
- }
- }
- if (!in_load_segment)
- gold_error(_("allocated section not in any PT_LOAD segment"));
- }
- }
- // Set the addresses for segments created from a PHDRS clause. Return
- // the segment which should hold the file header and program headers,
- // if any.
- Output_segment*
- Script_sections::set_phdrs_clause_addresses(Layout* layout,
- uint64_t dot_alignment)
- {
- Output_segment* load_seg = NULL;
- for (Phdrs_elements::const_iterator p = this->phdrs_elements_->begin();
- p != this->phdrs_elements_->end();
- ++p)
- {
- // Note that we have to set the flags after adding the output
- // sections to the segment, as adding an output segment can
- // change the flags.
- (*p)->set_flags_if_valid();
- Output_segment* oseg = (*p)->segment();
- if (oseg->type() != elfcpp::PT_LOAD)
- {
- // The addresses of non-PT_LOAD segments are set from the
- // PT_LOAD segments.
- if ((*p)->has_load_address())
- gold_error(_("may only specify load address for PT_LOAD segment"));
- continue;
- }
- oseg->set_minimum_p_align(dot_alignment);
- // The output sections should have addresses from the SECTIONS
- // clause. The addresses don't have to be in order, so find the
- // one with the lowest load address. Use that to set the
- // address of the segment.
- Output_section* osec = oseg->section_with_lowest_load_address();
- if (osec == NULL)
- {
- oseg->set_addresses(0, 0);
- continue;
- }
- uint64_t vma = osec->address();
- uint64_t lma = osec->has_load_address() ? osec->load_address() : vma;
- // Override the load address of the section with the load
- // address specified for the segment.
- if ((*p)->has_load_address())
- {
- if (osec->has_load_address())
- gold_warning(_("PHDRS load address overrides "
- "section %s load address"),
- osec->name());
- lma = (*p)->load_address();
- }
- bool headers = (*p)->includes_filehdr() && (*p)->includes_phdrs();
- if (!headers && ((*p)->includes_filehdr() || (*p)->includes_phdrs()))
- {
- // We could support this if we wanted to.
- gold_error(_("using only one of FILEHDR and PHDRS is "
- "not currently supported"));
- }
- if (headers)
- {
- size_t sizeof_headers = this->total_header_size(layout);
- uint64_t subtract = this->header_size_adjustment(lma,
- sizeof_headers);
- if (lma >= subtract && vma >= subtract)
- {
- lma -= subtract;
- vma -= subtract;
- }
- else
- {
- gold_error(_("sections loaded on first page without room "
- "for file and program headers "
- "are not supported"));
- }
- if (load_seg != NULL)
- gold_error(_("using FILEHDR and PHDRS on more than one "
- "PT_LOAD segment is not currently supported"));
- load_seg = oseg;
- }
- oseg->set_addresses(vma, lma);
- }
- return load_seg;
- }
- // Add the file header and segment headers to non-load segments
- // specified in the PHDRS clause.
- void
- Script_sections::put_headers_in_phdrs(Output_data* file_header,
- Output_data* segment_headers)
- {
- gold_assert(this->saw_phdrs_clause());
- for (Phdrs_elements::iterator p = this->phdrs_elements_->begin();
- p != this->phdrs_elements_->end();
- ++p)
- {
- if ((*p)->type() != elfcpp::PT_LOAD)
- {
- if ((*p)->includes_phdrs())
- (*p)->segment()->add_initial_output_data(segment_headers);
- if ((*p)->includes_filehdr())
- (*p)->segment()->add_initial_output_data(file_header);
- }
- }
- }
- // Look for an output section by name and return the address, the load
- // address, the alignment, and the size. This is used when an
- // expression refers to an output section which was not actually
- // created. This returns true if the section was found, false
- // otherwise.
- bool
- Script_sections::get_output_section_info(const char* name, uint64_t* address,
- uint64_t* load_address,
- uint64_t* addralign,
- uint64_t* size) const
- {
- if (!this->saw_sections_clause_)
- return false;
- for (Sections_elements::const_iterator p = this->sections_elements_->begin();
- p != this->sections_elements_->end();
- ++p)
- if ((*p)->get_output_section_info(name, address, load_address, addralign,
- size))
- return true;
- return false;
- }
- // Release all Output_segments. This remove all pointers to all
- // Output_segments.
- void
- Script_sections::release_segments()
- {
- if (this->saw_phdrs_clause())
- {
- for (Phdrs_elements::const_iterator p = this->phdrs_elements_->begin();
- p != this->phdrs_elements_->end();
- ++p)
- (*p)->release_segment();
- }
- this->segments_created_ = false;
- }
- // Print the SECTIONS clause to F for debugging.
- void
- Script_sections::print(FILE* f) const
- {
- if (this->phdrs_elements_ != NULL)
- {
- fprintf(f, "PHDRS {\n");
- for (Phdrs_elements::const_iterator p = this->phdrs_elements_->begin();
- p != this->phdrs_elements_->end();
- ++p)
- (*p)->print(f);
- fprintf(f, "}\n");
- }
- if (this->memory_regions_ != NULL)
- {
- fprintf(f, "MEMORY {\n");
- for (Memory_regions::const_iterator m = this->memory_regions_->begin();
- m != this->memory_regions_->end();
- ++m)
- (*m)->print(f);
- fprintf(f, "}\n");
- }
- if (!this->saw_sections_clause_)
- return;
- fprintf(f, "SECTIONS {\n");
- for (Sections_elements::const_iterator p = this->sections_elements_->begin();
- p != this->sections_elements_->end();
- ++p)
- (*p)->print(f);
- fprintf(f, "}\n");
- }
- } // End namespace gold.
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