// script-sections.cc -- linker script SECTIONS for gold
-// Copyright 2008 Free Software Foundation, Inc.
+// Copyright (C) 2008-2020 Free Software Foundation, Inc.
// Written by Ian Lance Taylor <iant@google.com>.
// This file is part of gold.
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
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()
// section name. This only real implementation is in
// Output_section_definition.
virtual const char*
- output_section_name(const char*, const char*, Output_section***)
+ output_section_name(const char*, const char*, Output_section***,
+ Script_sections::Section_type*, bool*, bool)
{ return NULL; }
- // Return whether to place an orphan output section after this
- // element.
- virtual bool
- place_orphan_here(const Output_section *, bool*, 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.
+ // expression is an absolute value.
virtual void
- set_section_addresses(Symbol_table*, Layout*, uint64_t*, uint64_t*)
+ set_section_addresses(Symbol_table*, Layout*, uint64_t*, uint64_t*,
+ uint64_t*)
{ }
// Check a constraint (ONLY_IF_RO, etc.) on an output section. If
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;
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.
// absolute symbols when setting dot.
void
set_section_addresses(Symbol_table* symtab, Layout* layout,
- uint64_t* dot_value, uint64_t*)
+ uint64_t* dot_value, uint64_t*, uint64_t*)
{
- this->assignment_.set_if_absolute(symtab, layout, true, *dot_value);
+ this->assignment_.set_if_absolute(symtab, layout, true, *dot_value, NULL);
}
// Print for debugging.
// We ignore the section of the result because outside of an
// output section definition the dot symbol is always considered
// to be absolute.
- Output_section* dummy;
*dot_value = this->val_->eval_with_dot(symtab, layout, true, *dot_value,
- NULL, &dummy);
+ 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* load_address)
+ uint64_t* dot_value, uint64_t* dot_alignment,
+ uint64_t* load_address)
{
- Output_section* dummy;
*dot_value = this->val_->eval_with_dot(symtab, layout, false, *dot_value,
- NULL, &dummy);
+ NULL, NULL, dot_alignment, false);
*load_address = *dot_value;
}
{
public:
// A list of input sections.
- typedef std::list<std::pair<Relobj*, unsigned int> > Input_section_list;
+ typedef std::list<Output_section::Input_section> Input_section_list;
Output_section_element()
{ }
// 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*) const
+ match_name(const char*, const char*, bool *) const
{ return false; }
// Set section addresses. This includes applying assignments if the
- // the expression is an absolute value.
+ // expression is an absolute value.
virtual void
set_section_addresses(Symbol_table*, Layout*, Output_section*, uint64_t,
- uint64_t*, Output_section**, std::string*,
+ uint64_t*, uint64_t*, Output_section**, std::string*,
Input_section_list*)
{ }
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.
// absolute symbols when setting dot.
void
set_section_addresses(Symbol_table* symtab, Layout* layout, Output_section*,
- uint64_t, uint64_t* dot_value, Output_section**,
- std::string*, Input_section_list*)
+ 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);
+ this->assignment_.set_if_absolute(symtab, layout, true, *dot_value,
+ *dot_section);
}
// Print for debugging.
: 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);
+ *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, Output_section**,
- std::string*, Input_section_list*);
+ uint64_t, uint64_t* dot_value, uint64_t*,
+ Output_section** dot_section, std::string*,
+ Input_section_list*);
// Print for debugging.
void
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_section, dot_alignment,
+ true);
if (next_dot < *dot_value)
gold_error(_("dot may not move backward"));
if (next_dot > *dot_value && output_section != NULL)
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)
{ }
void
Output_data_expression::do_write_to_buffer(unsigned char* buf)
{
- Output_section* dummy;
uint64_t val = this->val_->eval_with_dot(this->symtab_, this->layout_,
true, this->dot_value_,
- this->dot_section_, &dummy);
+ this->dot_section_, NULL, NULL,
+ false);
if (parameters->target().is_big_endian())
this->endian_write_to_buffer<true>(val, buf);
// Store the value in the section.
void
set_section_addresses(Symbol_table*, Layout*, Output_section*, uint64_t,
- uint64_t* dot_value, Output_section**, std::string*,
- Input_section_list*);
+ uint64_t* dot_value, uint64_t*, Output_section**,
+ std::string*, Input_section_list*);
// Print for debugging.
void
Output_section* os,
uint64_t,
uint64_t* dot_value,
+ uint64_t*,
Output_section** dot_section,
std::string*,
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_;
}
// 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, 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);
+ &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.
Expression* val_;
};
-// Return whether STRING contains a wildcard character. This is used
-// to speed up matching.
-
-static inline bool
-is_wildcard_string(const std::string& s)
-{
- return strpbrk(s.c_str(), "?*[") != NULL;
-}
-
// An input section specification in an output section
class Output_section_element_input : public Output_section_element
*dot_section = this->final_dot_section_;
}
- // See whether we match FILE_NAME and SECTION_NAME as an input
- // 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) const;
+ 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 subalign, uint64_t* dot_value, uint64_t*,
Output_section**, std::string* fill,
Input_section_list*);
Input_section_pattern(const char* patterna, size_t patternlena,
Sort_wildcard sorta)
: pattern(patterna, patternlena),
- pattern_is_wildcard(is_wildcard_string(this->pattern)),
+ pattern_is_wildcard(is_wildcard_string(this->pattern.c_str())),
sort(sorta)
{ }
};
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_);
+ this->filename_is_wildcard_ = is_wildcard_string(this->filename_pattern_.c_str());
if (spec->input_sections.exclude != NULL)
{
p != spec->input_sections.exclude->end();
++p)
{
- bool is_wildcard = is_wildcard_string(*p);
+ bool is_wildcard = is_wildcard_string((*p).c_str());
this->filename_exclusions_.push_back(std::make_pair(*p,
is_wildcard));
}
return true;
}
-// See whether we match FILE_NAME and SECTION_NAME.
+// 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) const
+ 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;
// 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::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.
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))
+ && 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 (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,
+ 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();
- if (input_pattern_count == 0)
- input_pattern_count = 1;
- Matching_sections matching_sections(input_pattern_count);
+ 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
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 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(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;
}
- if (i >= this->input_section_patterns_.size())
+ if (i >= input_pattern_count)
++p;
else
{
+ if (i >= bin_count)
+ i = 0;
matching_sections[i].push_back(isi);
p = input_sections->erase(p);
}
// sections are otherwise equal. Add each input section to the
// output section.
- for (size_t i = 0; i < input_pattern_count; ++i)
+ uint64_t dot = *dot_value;
+ for (size_t i = 0; i < bin_count; ++i)
{
if (matching_sections[i].empty())
continue;
p != matching_sections[i].end();
++p)
{
- uint64_t this_subalign = p->addralign;
- if (this_subalign < subalign)
- this_subalign = subalign;
+ // 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_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);
-
- *dot_value = address + p->size;
+ 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;
}
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();
}
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()
// section name.
const char*
output_section_name(const char* file_name, const char* section_name,
- Output_section***);
+ Output_section***, Script_sections::Section_type*,
+ bool*, bool);
- // Return whether to place an orphan section after this one.
- bool
- place_orphan_here(const Output_section *os, bool* exact, bool*) 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
set_section_addresses(Symbol_table* symtab, Layout* layout,
- uint64_t* dot_value, uint64_t* load_address);
+ 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,
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.
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.
evaluated_address_(0),
evaluated_load_address_(0),
evaluated_addralign_(0),
- is_relro_(false)
+ is_relro_(false),
+ script_section_type_(header->section_type)
{
}
if ((*p)->needs_output_section())
{
const char* name = this->name_.c_str();
- this->output_section_ = layout->make_output_section_for_script(name);
+ this->output_section_ =
+ layout->make_output_section_for_script(name, this->section_type());
return;
}
}
uint64_t address = *dot_value;
if (this->address_ != NULL)
{
- Output_section* dummy;
address = this->address_->eval_with_dot(symtab, layout, true,
*dot_value, NULL,
- &dummy);
+ NULL, NULL, false);
}
if (this->align_ != NULL)
{
- Output_section* dummy;
uint64_t align = this->align_->eval_with_dot(symtab, layout, true,
- *dot_value,
- NULL,
- &dummy);
+ *dot_value, NULL,
+ NULL, NULL, false);
address = align_address(address, align);
}
*dot_value = address;
// 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)
+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))
+ 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();
}
}
return NULL;
}
-// Return whether to place an orphan output section after this
-// section.
+// Return true if memory from START to START + LENGTH is contained
+// within a memory region.
bool
-Output_section_definition::place_orphan_here(const Output_section *os,
- bool* exact,
- bool* is_relro) const
+Script_sections::block_in_region(Symbol_table* symtab, Layout* layout,
+ uint64_t start, uint64_t length) const
{
- *is_relro = this->is_relro_;
+ if (this->memory_regions_ == NULL)
+ return false;
- // Check for the simple case first.
- if (this->output_section_ != NULL
- && this->output_section_->type() == os->type()
- && this->output_section_->flags() == os->flags())
+ for (Memory_regions::const_iterator mr = this->memory_regions_->begin();
+ mr != this->memory_regions_->end();
+ ++mr)
{
- *exact = true;
- return true;
+ 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;
}
- // Otherwise use some heuristics.
+ return false;
+}
- if ((os->flags() & elfcpp::SHF_ALLOC) == 0)
- 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.
- 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)
+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 (this->name_ == ".data")
+ if (find_vma_region)
{
- *exact = true;
- return true;
+ 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;
+ }
}
- 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")
+ else
{
- *exact = true;
- return true;
+ 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 (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")
+
+ if (!explicit_only)
{
- *exact = true;
- return true;
+ // 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;
}
- if (this->output_section_ != NULL
- && this->output_section_->type() == elfcpp::SHT_PROGBITS
- && (this->output_section_->flags() & elfcpp::SHF_WRITE) == 0)
- return true;
}
- return false;
+ // 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
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;
- if (this->address_ == NULL)
- address = *dot_value;
+ 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
{
- Output_section* dummy;
+ vma_region = script_sections->find_memory_region(this, true, true, NULL);
address = this->address_->eval_with_dot(symtab, layout, true,
- *dot_value, NULL, &dummy);
+ *dot_value, NULL, NULL,
+ dot_alignment, false);
+ if (vma_region != NULL)
+ vma_region->set_address(address, symtab, layout);
}
uint64_t align;
{
Output_section* align_section;
align = this->align_->eval_with_dot(symtab, layout, true, *dot_value,
- NULL, &align_section);
+ NULL, &align_section, NULL, false);
if (align_section != NULL)
gold_warning(_("alignment of section %s is not absolute"),
this->name_.c_str());
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;
- // The address of non-SHF_ALLOC sections is forced to zero,
- // regardless of what the linker script wants.
+ // 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_->flags() & elfcpp::SHF_ALLOC) != 0
+ || this->output_section_->is_noload()))
this->output_section_->set_address(address);
this->evaluated_address_ = address;
this->evaluated_addralign_ = align;
- if (this->load_address_ == NULL)
- this->evaluated_load_address_ = address;
+ 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
{
- Output_section* dummy;
- uint64_t load_address =
- this->load_address_->eval_with_dot(symtab, layout, true, *dot_value,
- this->output_section_, &dummy);
+ 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(load_address);
- this->evaluated_load_address_ = load_address;
+ this->output_section_->set_load_address(laddr);
}
- 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);
- if (subalign_section != NULL)
- gold_warning(_("subalign of section %s is not absolute"),
- this->name_.c_str());
- }
+ this->evaluated_load_address_ = laddr;
std::string fill;
if (this->fill_ != NULL)
Output_section* fill_section;
uint64_t fill_val = this->fill_->eval_with_dot(symtab, layout, true,
*dot_value,
- NULL,
- &fill_section);
+ NULL, &fill_section,
+ NULL, false);
if (fill_section != NULL)
gold_warning(_("fill of section %s is not absolute"),
this->name_.c_str());
p != this->elements_.end();
++p)
(*p)->set_section_addresses(symtab, layout, this->output_section_,
- subalign, dot_value, &dot_section, &fill,
- &input_sections);
+ subalign, dot_value, dot_alignment,
+ &dot_section, &fill, &input_sections);
gold_assert(input_sections.empty());
- if (this->load_address_ == NULL || this->output_section_ == NULL)
+ 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));
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;
+ }
}
}
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;
- if (this->phdrs_ != NULL)
- *phdrs_list = this->phdrs_;
return this->output_section_;
}
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, "\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
: 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, bool*) 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
- set_section_addresses(Symbol_table*, Layout*, uint64_t*, uint64_t*);
+ 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* os_;
};
-// Whether to place another orphan section after this one.
-
-bool
-Orphan_output_section::place_orphan_here(const Output_section* os,
- bool* exact,
- bool* is_relro) const
-{
- if (this->os_->type() == os->type()
- && this->os_->flags() == os->flags())
- {
- *exact = true;
- *is_relro = this->os_->is_relro();
- return true;
- }
- return false;
-}
-
// 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<std::pair<Relobj*, unsigned int> > Input_section_list;
+ 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);
p != input_sections.end();
++p)
{
- uint64_t addralign;
- uint64_t size;
-
- // We know what are single-threaded, so it is OK to lock the
- // 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);
- }
-
+ 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_input_section_for_script(p->first, p->second, size,
- addralign);
+ this->os_->add_script_input_section(*p);
address += size;
}
- if (!have_load_address)
- *load_address = address;
- else
- *load_address += address - *dot_value;
+ 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;
+ *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()
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()
in_sections_clause_(false),
sections_elements_(NULL),
output_section_(NULL),
+ memory_regions_(NULL),
phdrs_elements_(NULL),
- data_segment_align_index_(-1U),
- saw_relro_end_(false)
+ 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)
{
}
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);
}
Script_sections::start_output_section(
const char* name,
size_t namelen,
- const Parser_output_section_header *header)
+ const Parser_output_section_header* header)
{
Output_section_definition* posd = new Output_section_definition(name,
namelen,
void
Script_sections::data_segment_align()
{
- if (this->data_segment_align_index_ != -1U)
+ if (this->saw_data_segment_align_)
gold_error(_("DATA_SEGMENT_ALIGN may only appear once in a linker script"));
- this->data_segment_align_index_ = this->sections_elements_->size();
+ 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
"in a linker script"));
this->saw_relro_end_ = true;
- if (this->data_segment_align_index_ == -1U)
+ if (!this->saw_data_segment_align_)
gold_error(_("DATA_SEGMENT_RELRO_END must follow DATA_SEGMENT_ALIGN"));
else
{
- for (size_t i = this->data_segment_align_index_;
- i < this->sections_elements_->size();
- ++i)
- (*this->sections_elements_)[i]->set_is_relro();
+ Sections_elements::iterator p = this->data_segment_align_start_;
+ for (++p; p != this->sections_elements_->end(); ++p)
+ (*p)->set_is_relro();
}
}
// 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::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);
+ output_section_slot,
+ psection_type, keep,
+ is_input_section);
if (ret != NULL)
{
if (strcmp(ret, "/DISCARD/") == 0)
{
*output_section_slot = NULL;
+ *psection_type = Script_sections::ST_NONE;
return NULL;
}
return ret;
}
}
- // If we couldn't find a mapping for the name, the output section
- // gets the name of the input section.
-
+ // 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;
}
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.
- bool is_relro = false;
- 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;
- bool is_relro_here;
- if ((*p)->place_orphan_here(os, &exact, &is_relro_here))
- {
- place = p;
- is_relro = is_relro_here;
- 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));
-
- if (is_relro)
- os->set_is_relro();
+ // 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();
+ {
+ 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
p != this->sections_elements_->end();
++p)
{
- Output_section *os = (*p)->get_output_section();
+ Output_section* os = (*p)->get_output_section();
if (os != NULL && (os->flags() & elfcpp::SHF_TLS) != 0)
{
if (first_tls == NULL)
// 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)
- (*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, &dot_alignment,
+ &load_address);
+ }
if (this->phdrs_elements_ != NULL)
{
(*p)->eval_load_address(symtab, layout);
}
- return this->create_segments(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
if (os1->address() != os2->address())
return os1->address() < os2->address();
- // Sort TLS sections to the end.
+ // 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 tls2;
+ return nobits1 ? tls1 : tls2;
- // Sort PROGBITS before NOBITS.
- if (os1->type() == elfcpp::SHT_PROGBITS && os2->type() == elfcpp::SHT_NOBITS)
+ // Sort non-NOLOAD before NOLOAD.
+ if (os1->is_noload() && !os2->is_noload())
+ return true;
+ if (!os1->is_noload() && os2->is_noload())
return true;
- if (os1->type() == elfcpp::SHT_NOBITS && os2->type() == elfcpp::SHT_PROGBITS)
- return false;
- // Otherwise we don't care.
- return false;
+ // 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.
return file_header_size + segment_headers_size;
}
-// Return the amount we have to subtract from the LMA to accomodate
+// 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.
// if any.
Output_segment*
-Script_sections::create_segments(Layout* layout)
+Script_sections::create_segments(Layout* layout, uint64_t dot_alignment)
{
gold_assert(this->saw_sections_clause_);
return NULL;
if (this->saw_phdrs_clause())
- return create_segments_from_phdrs_clause(layout);
+ 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());
+ std::stable_sort(sections.begin(), sections.end(),
+ Sort_output_sections(this->sections_elements_));
this->create_note_and_tls_segments(layout, §ions);
Output_segment* first_seg = NULL;
Output_segment* current_seg = NULL;
bool is_current_seg_readonly = true;
- Layout::Section_list::iterator plast = sections.end();
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)
// skipping a page.
need_new_segment = true;
}
- else if (is_bss_section(*plast) && !is_bss_section(*p))
+ else if (in_bss && !is_bss_section(*p))
{
// A non-BSS section can not follow a BSS section in the
// same 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(*p, seg_flags);
+ current_seg->add_output_section_to_load(layout, *p, seg_flags);
if (((*p)->flags() & elfcpp::SHF_WRITE) != 0)
is_current_seg_readonly = false;
- plast = p;
+ if (is_bss_section(*p) && size > 0)
+ in_bss = true;
+
last_vma = vma;
last_lma = lma;
last_size = size;
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();
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);
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_to_nonload(*p, seg_flags);
// 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_to_nonload(*pnext, seg_flags);
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_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(*pnext, seg_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 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,
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();
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)
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;
// should hold the file header and program headers, if any.
Output_segment*
-Script_sections::create_segments_from_phdrs_clause(Layout* layout)
+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);
+ return this->set_phdrs_clause_addresses(layout, dot_alignment);
}
// Create the segments from the PHDRS clause, and put the output
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 orphan;
- Output_section* os = (*p)->allocate_to_segment(&phdr_names, &orphan);
+ 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)
{
- gold_error(_("allocated section not in any segment"));
+ // 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 (orphan)
+ if (is_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
{
- elfcpp::Elf_Word seg_flags =
- Layout::section_flags_to_segment(os->flags());
- r->second->add_output_section(os, seg_flags);
+ if (load_segments_only
+ && r->second->type() != elfcpp::PT_LOAD)
+ continue;
- if (r->second->type() == elfcpp::PT_LOAD)
+ 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 any.
Output_segment*
-Script_sections::set_phdrs_clause_addresses(Layout* layout)
+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();
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
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;
(*p)->print(f);
fprintf(f, "}\n");
-
- 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");
- }
}
} // End namespace gold.
projects / deliverable / binutils-gdb.git / blobdiff