// script-sections.cc -- linker script SECTIONS for gold
-// Copyright 2008 Free Software Foundation, Inc.
+// Copyright 2008, 2009 Free Software Foundation, Inc.
// Written by Ian Lance Taylor <iant@google.com>.
// This file is part of gold.
namespace gold
{
+// 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);
+
+ // 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_BSS,
+ 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_BSS, ".bss");
+ 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;
+
+ 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 (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_BSS:
+ follow = PLACE_DATA;
+ break;
+ case PLACE_REL:
+ follow = PLACE_TEXT;
+ break;
+ case PLACE_INTERP:
+ follow = PLACE_TEXT;
+ 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;
+}
+
+// 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
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
output_section_name(const char*, const char*, Output_section***)
{ return NULL; }
- // Return whether to place an orphan output section after this
- // element.
- virtual bool
- place_orphan_here(const Output_section *, bool*) const
- { return false; }
+ // 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
// the expression is an absolute value.
uint64_t*) const
{ return false; }
+ // Return the associated Output_section if there is one.
+ virtual Output_section*
+ get_output_section() const
+ { return NULL; }
+
// Print the element for debugging purposes.
virtual void
print(FILE* f) const = 0;
public:
Sections_element_assignment(const char* name, size_t namelen,
Expression* val, bool provide, bool hidden)
- : assignment_(name, namelen, val, provide, hidden)
+ : assignment_(name, namelen, false, val, provide, hidden)
{ }
// Add the symbol to the symbol table.
{
public:
// A list of input sections.
- typedef std::list<std::pair<Relobj*, unsigned int> > Input_section_list;
+ typedef std::list<Output_section::Simple_input_section> Input_section_list;
Output_section_element()
{ }
Output_section_element_assignment(const char* name, size_t namelen,
Expression* val, bool provide,
bool hidden)
- : assignment_(name, namelen, val, provide, hidden)
+ : assignment_(name, namelen, false, val, provide, hidden)
{ }
// Add the symbol to the symbol table.
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;
}
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),
+ : Output_section_data(size, 0, true),
is_signed_(is_signed), val_(val), symtab_(symtab),
layout_(layout), dot_value_(dot_value), dot_section_(dot_section)
{ }
Input_section_list*)
{
gold_assert(os != NULL);
- os->add_output_section_data(new Output_data_expression(this->size_,
- this->is_signed_,
- this->val_,
- symtab,
- layout,
- *dot_value,
- *dot_section));
+ 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_;
}
// Information we use to sort the input sections.
-struct Input_section_info
+class Input_section_info
{
- Relobj* relobj;
- unsigned int shndx;
- std::string section_name;
- uint64_t size;
- uint64_t addralign;
+ public:
+ Input_section_info(const Output_section::Simple_input_section& input_section)
+ : input_section_(input_section), section_name_(),
+ size_(0), addralign_(1)
+ { }
+
+ // Return the simple input section.
+ const Output_section::Simple_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)
+ { 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::Simple_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.
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))
+ && isi1.addralign() == isi2.addralign()))
{
- if (isi1.section_name != isi2.section_name)
- return isi1.section_name < isi2.section_name;
+ 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 (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();
+ if (isi1.relobj()->name() != isi2.relobj()->name())
+ return (isi1.relobj()->name() < isi2.relobj()->name());
}
// Otherwise we leave them in the same order.
void
Output_section_element_input::set_section_addresses(
Symbol_table*,
- Layout*,
+ Layout* layout,
Output_section* output_section,
uint64_t subalign,
uint64_t* dot_value,
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.
- Input_section_info isi;
- isi.relobj = p->first;
- isi.shndx = p->second;
// 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, p->first);
-
- isi.section_name = p->first->section_name(p->second);
- isi.size = p->first->section_size(p->second);
- isi.addralign = p->first->section_addralign(p->second);
+ 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 relxed 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(isi.relobj->name().c_str()))
+ if (!this->match_file_name(relobj->name().c_str()))
++p;
else if (this->input_section_patterns_.empty())
{
{
const Input_section_pattern&
isp(this->input_section_patterns_[i]);
- if (match(isi.section_name.c_str(), isp.pattern.c_str(),
+ if (match(isi.section_name().c_str(), isp.pattern.c_str(),
isp.pattern_is_wildcard))
break;
}
// sections are otherwise equal. Add each input section to the
// output section.
+ uint64_t dot = *dot_value;
for (size_t i = 0; i < input_pattern_count; ++i)
{
if (matching_sections[i].empty())
p != matching_sections[i].end();
++p)
{
- uint64_t this_subalign = p->addralign;
+ uint64_t this_subalign = p->addralign();
if (this_subalign < subalign)
this_subalign = subalign;
- uint64_t address = align_address(*dot_value, this_subalign);
+ uint64_t address = align_address(dot, this_subalign);
- if (address > *dot_value && !fill->empty())
+ if (address > dot && !fill->empty())
{
section_size_type length =
- convert_to_section_size_type(address - *dot_value);
+ 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_input_section_for_script(p->relobj,
- p->shndx,
- p->size,
- this_subalign);
+ output_section->add_simple_input_section(p->input_section(),
+ p->size(),
+ this_subalign);
- *dot_value = address + p->size;
+ dot = address + p->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;
}
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*);
output_section_name(const char* file_name, const char* section_name,
Output_section***);
- // Return whether to place an orphan section after this one.
- bool
- place_orphan_here(const Output_section *os, bool* exact) const;
+ // 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
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;
uint64_t evaluated_load_address_;
// The alignment after it has been evaluated.
uint64_t evaluated_addralign_;
+ // The output section is relro.
+ bool is_relro_;
};
// Constructor.
fill_(NULL),
phdrs_(NULL),
elements_(),
- output_section_(NULL)
+ output_section_(NULL),
+ evaluated_address_(0),
+ evaluated_load_address_(0),
+ evaluated_addralign_(0),
+ is_relro_(false)
{
}
return NULL;
}
-// Return whether to place an orphan output section after this
-// section.
-
-bool
-Output_section_definition::place_orphan_here(const Output_section *os,
- bool* exact) const
-{
- // Check for the simple case first.
- if (this->output_section_ != NULL
- && this->output_section_->type() == os->type()
- && this->output_section_->flags() == os->flags())
- {
- *exact = true;
- return true;
- }
-
- // Otherwise use some heuristics.
-
- if ((os->flags() & elfcpp::SHF_ALLOC) == 0)
- return false;
-
- if (os->type() == elfcpp::SHT_NOBITS)
- {
- if (this->name_ == ".bss")
- {
- *exact = true;
- return true;
- }
- if (this->output_section_ != NULL
- && this->output_section_->type() == elfcpp::SHT_NOBITS)
- return true;
- }
- else if (os->type() == elfcpp::SHT_NOTE)
- {
- if (this->output_section_ != NULL
- && this->output_section_->type() == elfcpp::SHT_NOTE)
- {
- *exact = true;
- return true;
- }
- if (this->name_.compare(0, 5, ".note") == 0)
- {
- *exact = true;
- return true;
- }
- if (this->name_ == ".interp")
- return true;
- if (this->output_section_ != NULL
- && this->output_section_->type() == elfcpp::SHT_PROGBITS
- && (this->output_section_->flags() & elfcpp::SHF_WRITE) == 0)
- return true;
- }
- else if (os->type() == elfcpp::SHT_REL || os->type() == elfcpp::SHT_RELA)
- {
- if (this->name_.compare(0, 4, ".rel") == 0)
- {
- *exact = true;
- return true;
- }
- if (this->output_section_ != NULL
- && (this->output_section_->type() == elfcpp::SHT_REL
- || this->output_section_->type() == elfcpp::SHT_RELA))
- {
- *exact = true;
- return true;
- }
- if (this->output_section_ != NULL
- && this->output_section_->type() == elfcpp::SHT_PROGBITS
- && (this->output_section_->flags() & elfcpp::SHF_WRITE) == 0)
- return true;
- }
- else if (os->type() == elfcpp::SHT_PROGBITS
- && (os->flags() & elfcpp::SHF_WRITE) != 0)
- {
- if (this->name_ == ".data")
- {
- *exact = true;
- return true;
- }
- if (this->output_section_ != NULL
- && this->output_section_->type() == elfcpp::SHT_PROGBITS
- && (this->output_section_->flags() & elfcpp::SHF_WRITE) != 0)
- return true;
- }
- else if (os->type() == elfcpp::SHT_PROGBITS
- && (os->flags() & elfcpp::SHF_EXECINSTR) != 0)
- {
- if (this->name_ == ".text")
- {
- *exact = true;
- return true;
- }
- if (this->output_section_ != NULL
- && this->output_section_->type() == elfcpp::SHT_PROGBITS
- && (this->output_section_->flags() & elfcpp::SHF_EXECINSTR) != 0)
- return true;
- }
- else if (os->type() == elfcpp::SHT_PROGBITS
- || (os->type() != elfcpp::SHT_PROGBITS
- && (os->flags() & elfcpp::SHF_WRITE) == 0))
- {
- if (this->name_ == ".rodata")
- {
- *exact = true;
- return true;
- }
- if (this->output_section_ != NULL
- && this->output_section_->type() == elfcpp::SHT_PROGBITS
- && (this->output_section_->flags() & elfcpp::SHF_WRITE) == 0)
- return true;
- }
-
- return false;
-}
-
// 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.
else
{
Output_section* dummy;
- uint64_t load_address =
+ uint64_t laddr =
this->load_address_->eval_with_dot(symtab, layout, true, *dot_value,
this->output_section_, &dummy);
if (this->output_section_ != NULL)
- this->output_section_->set_load_address(load_address);
- this->evaluated_load_address_ = load_address;
+ this->output_section_->set_load_address(laddr);
+ this->evaluated_load_address_ = laddr;
}
uint64_t subalign;
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();
+ }
}
// Check a constraint (ONLY_IF_RO, etc.) on an output section. If
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;
}
: os_(os)
{ }
- // Return whether to place an orphan section after this one.
+ // 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
- place_orphan_here(const Output_section *os, bool* exact) const;
+ 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
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
Output_section* os_;
};
-// Whether to place another orphan section after this one.
-
-bool
-Orphan_output_section::place_orphan_here(const Output_section* os,
- bool* exact) const
-{
- if (this->os_->type() == os->type()
- && this->os_->flags() == os->flags())
- {
- *exact = true;
- return true;
- }
- return false;
-}
-
// Set section addresses.
void
uint64_t* dot_value,
uint64_t* load_address)
{
- typedef std::list<std::pair<Relobj*, unsigned int> > Input_section_list;
+ typedef std::list<Output_section::Simple_input_section> Input_section_list;
bool have_load_address = *load_address != *dot_value;
// object.
{
const Task* task = reinterpret_cast<const Task*>(-1);
- Task_lock_obj<Object> tl(task, p->first);
- addralign = p->first->section_addralign(p->second);
- size = p->first->section_size(p->second);
+ Task_lock_obj<Object> tl(task, p->relobj());
+ addralign = p->relobj()->section_addralign(p->shndx());
+ if (p->is_relaxed_input_section())
+ // We use current data size because relxed section sizes may not
+ // have finalized yet.
+ size = p->relaxed_input_section()->current_data_size();
+ else
+ size = p->relobj()->section_size(p->shndx());
}
address = align_address(address, addralign);
- this->os_->add_input_section_for_script(p->first, p->second, size,
- addralign);
+ this->os_->add_simple_input_section(*p, size, addralign);
address += size;
}
- if (!have_load_address)
- *load_address = address;
- else
- *load_address += address - *dot_value;
+ // An SHF_TLS/SHT_NOBITS section does not take up any address space.
+ if (this->os_ == NULL
+ || (this->os_->flags() & elfcpp::SHF_TLS) == 0
+ || this->os_->type() != elfcpp::SHT_NOBITS)
+ {
+ if (!have_load_address)
+ *load_address = address;
+ else
+ *load_address += address - *dot_value;
- *dot_value = address;
+ *dot_value = address;
+ }
}
// Get the list of segments to use for an allocated section when using
segment()
{ return this->segment_; }
+ // Release the segment.
+ void
+ release_segment()
+ { this->segment_ = NULL; }
+
// Set the segment flags if appropriate.
void
set_flags_if_valid()
in_sections_clause_(false),
sections_elements_(NULL),
output_section_(NULL),
- phdrs_elements_(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)
{
}
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);
}
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
void
Script_sections::place_orphan(Output_section* os)
{
- // Look for an output section definition which matches the output
- // section. Put a marker after that section.
- Sections_elements::iterator place = this->sections_elements_->end();
- for (Sections_elements::iterator p = this->sections_elements_->begin();
- p != this->sections_elements_->end();
- ++p)
+ Orphan_section_placement* osp = this->orphan_section_placement_;
+ if (osp == NULL)
{
- bool exact = false;
- if ((*p)->place_orphan_here(os, &exact))
- {
- place = p;
- if (exact)
- break;
- }
+ // 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;
}
- // The insert function puts the new element before the iterator.
- if (place != this->sections_elements_->end())
- ++place;
+ Orphan_output_section* orphan = new Orphan_output_section(os);
- this->sections_elements_->insert(place, 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);
+ }
}
// Set the addresses of all the output sections. Walk through all the
}
}
+ // 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 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)
- (*p)->set_section_addresses(symtab, layout, &dot_value, &load_address);
+ {
+ 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, &load_address);
+ }
if (this->phdrs_elements_ != NULL)
{
need_new_segment = true;
}
else if (is_current_seg_readonly
- && ((*p)->flags() & elfcpp::SHF_WRITE) != 0)
+ && ((*p)->flags() & elfcpp::SHF_WRITE) != 0
+ && !parameters->options().omagic())
{
// Don't put a writable section in the same segment as a
// non-writable section.
is_current_seg_readonly = true;
}
- current_seg->add_output_section(*p, seg_flags);
+ current_seg->add_output_section(*p, seg_flags, false);
if (((*p)->flags() & elfcpp::SHF_WRITE) != 0)
is_current_seg_readonly = false;
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();
Layout::section_flags_to_segment((*p)->flags());
Output_segment* oseg = layout->make_output_segment(elfcpp::PT_NOTE,
seg_flags);
- oseg->add_output_section(*p, seg_flags);
+ oseg->add_output_section(*p, seg_flags, false);
// Incorporate any subsequent SHT_NOTE sections, in the
// hopes that the script is sensible.
&& (*pnext)->type() == elfcpp::SHT_NOTE)
{
seg_flags = Layout::section_flags_to_segment((*pnext)->flags());
- oseg->add_output_section(*pnext, seg_flags);
+ oseg->add_output_section(*pnext, seg_flags, false);
p = pnext;
++pnext;
}
Layout::section_flags_to_segment((*p)->flags());
Output_segment* oseg = layout->make_output_segment(elfcpp::PT_TLS,
seg_flags);
- oseg->add_output_section(*p, seg_flags);
+ oseg->add_output_section(*p, seg_flags, false);
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(*pnext, seg_flags);
+ oseg->add_output_section(*pnext, seg_flags, false);
p = pnext;
++pnext;
}
// Add a program header. The PHDRS clause is syntactically distinct
// from the SECTIONS clause, but we implement it with the SECTIONS
-// support becauase PHDRS is useless if there is no SECTIONS clause.
+// 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,
// 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 orphan;
+ String_list* old_phdr_names = phdr_names;
Output_section* os = (*p)->allocate_to_segment(&phdr_names, &orphan);
if (os == NULL)
continue;
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
// we trust the linker script.
if (orphan)
{
- String_list::iterator q = phdr_names->begin();
- while (q != phdr_names->end())
- {
- Name_to_segment::const_iterator r = name_to_segment.find(*q);
- // We give errors about unknown segments below.
- if (r == name_to_segment.end()
- || r->second->type() == elfcpp::PT_LOAD)
- ++q;
- else
- q = phdr_names->erase(q);
- }
+ // Enable PT_LOAD segments only filtering until we see another
+ // list of segment names.
+ load_segments_only = true;
}
bool in_load_segment = false;
gold_error(_("no segment %s"), q->c_str());
else
{
+ if (load_segments_only
+ && r->second->type() != elfcpp::PT_LOAD)
+ continue;
+
elfcpp::Elf_Word seg_flags =
Layout::section_flags_to_segment(os->flags());
- r->second->add_output_section(os, seg_flags);
+ r->second->add_output_section(os, seg_flags, false);
if (r->second->type() == elfcpp::PT_LOAD)
{
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();
+ }
+}
+
// Print the SECTIONS clause to F for debugging.
void