aboutsummaryrefslogtreecommitdiff
path: root/gold/layout.cc
diff options
context:
space:
mode:
authorIan Lance Taylor <ian@airs.com>2008-04-15 04:06:41 +0000
committerIan Lance Taylor <ian@airs.com>2008-04-15 04:06:41 +0000
commit154e0e9aa714f93206c01ab62920a8ce9220fd9c (patch)
treeaebc9ca53e196a0c1f6b1ba7a26ad85a5a5ba25a /gold/layout.cc
parent9380031c3f42602e95f277a96b4c90d81f429915 (diff)
downloadgdb-154e0e9aa714f93206c01ab62920a8ce9220fd9c.zip
gdb-154e0e9aa714f93206c01ab62920a8ce9220fd9c.tar.gz
gdb-154e0e9aa714f93206c01ab62920a8ce9220fd9c.tar.bz2
* layout.cc (Layout::Layout): Initialize sections_are_attached_.
(Layout::get_output_section): Ignore SHF_WRITE and SHF_EXECINSTR in the name/type/flags to section mapping. Don't call allocate_output_section. (Layout::choose_output_section): Change parameter from adjust_name to is_input_section. Don't permit input sections after sections are attached to segments. Don't call allocate_output_section. (Layout::layout_eh_frame): Call update_flags_for_input_section, not write_enable_output_section. (Layout::make_output_section): Don't push to unattached_section_list_ nor call attach_to_segment. Call attach_section_to_segment if sections are attached. (Layout::attach_sections_to_segments): New function. (Layout::attach_section_to_segment): New function. (Layout::attach_allocated_section_to_segment): Rename from attach_to_segment. Remove flags parameter. (Layout::allocate_output_section): Remove function. (Layout::write_enable_output_section): Remove function. * layout.h (class Layout): Update for above changes. Add new field sections_are_attached_. * output.h (Output_section::update_flags_for_input_section): New function. * output.cc (Output_section::add_input_section): Call update_flags_for_input_section. * gold.cc (queue_middle_tasks): Call attach_sections_to_segments.
Diffstat (limited to 'gold/layout.cc')
-rw-r--r--gold/layout.cc158
1 files changed, 62 insertions, 96 deletions
diff --git a/gold/layout.cc b/gold/layout.cc
index efeaf65..76b6b2b 100644
--- a/gold/layout.cc
+++ b/gold/layout.cc
@@ -79,10 +79,10 @@ Layout::Layout(const General_options& options, Script_options* script_options)
: options_(options), script_options_(script_options), namepool_(),
sympool_(), dynpool_(), signatures_(),
section_name_map_(), segment_list_(), section_list_(),
- unattached_section_list_(), special_output_list_(),
- section_headers_(NULL), tls_segment_(NULL), symtab_section_(NULL),
- dynsym_section_(NULL), dynamic_section_(NULL), dynamic_data_(NULL),
- eh_frame_section_(NULL), eh_frame_data_(NULL),
+ unattached_section_list_(), sections_are_attached_(false),
+ special_output_list_(), section_headers_(NULL), tls_segment_(NULL),
+ symtab_section_(NULL), dynsym_section_(NULL), dynamic_section_(NULL),
+ dynamic_data_(NULL), eh_frame_section_(NULL), eh_frame_data_(NULL),
added_eh_frame_data_(false), eh_frame_hdr_section_(NULL),
build_id_note_(NULL), group_signatures_(), output_file_size_(-1),
input_requires_executable_stack_(false),
@@ -234,7 +234,15 @@ Output_section*
Layout::get_output_section(const char* name, Stringpool::Key name_key,
elfcpp::Elf_Word type, elfcpp::Elf_Xword flags)
{
- const Key key(name_key, std::make_pair(type, flags));
+ elfcpp::Elf_Xword lookup_flags = flags;
+
+ // Ignoring SHF_WRITE and SHF_EXECINSTR here means that we combine
+ // read-write with read-only sections. Some other ELF linkers do
+ // not do this. FIXME: Perhaps there should be an option
+ // controlling this.
+ lookup_flags &= ~(elfcpp::SHF_WRITE | elfcpp::SHF_EXECINSTR);
+
+ const Key key(name_key, std::make_pair(type, lookup_flags));
const std::pair<Key, Output_section*> v(key, NULL);
std::pair<Section_name_map::iterator, bool> ins(
this->section_name_map_.insert(v));
@@ -268,11 +276,7 @@ Layout::get_output_section(const char* name, Stringpool::Key name_key,
Section_name_map::iterator p =
this->section_name_map_.find(zero_key);
if (p != this->section_name_map_.end())
- {
- os = p->second;
- if ((flags & elfcpp::SHF_ALLOC) != 0)
- this->allocate_output_section(os, flags);
- }
+ os = p->second;
}
}
@@ -285,17 +289,22 @@ Layout::get_output_section(const char* name, Stringpool::Key name_key,
// Pick the output section to use for section NAME, in input file
// RELOBJ, with type TYPE and flags FLAGS. RELOBJ may be NULL for a
-// linker created section. ADJUST_NAME is true if we should apply the
-// standard name mappings in Layout::output_section_name. This will
-// return NULL if the input section should be discarded.
+// linker created section. IS_INPUT_SECTION is true if we are
+// choosing an output section for an input section found in a input
+// file. This will return NULL if the input section should be
+// discarded.
Output_section*
Layout::choose_output_section(const Relobj* relobj, const char* name,
elfcpp::Elf_Word type, elfcpp::Elf_Xword flags,
- bool adjust_name)
+ bool is_input_section)
{
- // We should ignore some flags. FIXME: This will need some
- // adjustment for ld -r.
+ // We should not see any input sections after we have attached
+ // sections to segments.
+ gold_assert(!is_input_section || !this->sections_are_attached_);
+
+ // Some flags in the input section should not be automatically
+ // copied to the output section.
flags &= ~ (elfcpp::SHF_INFO_LINK
| elfcpp::SHF_LINK_ORDER
| elfcpp::SHF_GROUP
@@ -324,17 +333,7 @@ Layout::choose_output_section(const Relobj* relobj, const char* name,
if (output_section_slot != NULL)
{
if (*output_section_slot != NULL)
- {
- // If the output section was created unallocated, and we
- // are now allocating it, then we need to clear the
- // address set in the constructor and remove it from the
- // unattached section list.
- if (((*output_section_slot)->flags() & elfcpp::SHF_ALLOC) == 0
- && (flags & elfcpp::SHF_ALLOC) != 0)
- this->allocate_output_section(*output_section_slot, flags);
-
- return *output_section_slot;
- }
+ return *output_section_slot;
// We don't put sections found in the linker script into
// SECTION_NAME_MAP_. That keeps us from getting confused
@@ -356,7 +355,7 @@ Layout::choose_output_section(const Relobj* relobj, const char* name,
// output section.
size_t len = strlen(name);
- if (adjust_name && !parameters->options().relocatable())
+ if (is_input_section && !parameters->options().relocatable())
name = Layout::output_section_name(name, &len);
Stringpool::Key name_key;
@@ -550,16 +549,6 @@ Layout::layout_eh_frame(Sized_relobj<size, big_endian>* object,
if (os == NULL)
return NULL;
- // On some targets gcc assumes that a read-only .eh_frame section
- // will be merged with a read-write .eh_frame section.
- if ((shdr.get_sh_flags() & elfcpp::SHF_WRITE) != 0
- && (os->flags() & elfcpp::SHF_WRITE) == 0)
- {
- elfcpp::Elf_Xword new_flags = os->flags() | elfcpp::SHF_WRITE;
- this->write_enable_output_section(os, new_flags);
- os->set_flags(new_flags);
- }
-
if (this->eh_frame_section_ == NULL)
{
this->eh_frame_section_ = os;
@@ -606,6 +595,8 @@ Layout::layout_eh_frame(Sized_relobj<size, big_endian>* object,
reloc_shndx,
reloc_type))
{
+ os->update_flags_for_input_section(shdr.get_sh_flags());
+
// We found a .eh_frame section we are going to optimize, so now
// we can add the set of optimized sections to the output
// section. We need to postpone adding this until we've found a
@@ -689,11 +680,6 @@ Layout::make_output_section(const char* name, elfcpp::Elf_Word type,
this->section_list_.push_back(os);
- if ((flags & elfcpp::SHF_ALLOC) == 0)
- this->unattached_section_list_.push_back(os);
- else
- this->attach_to_segment(os, flags);
-
// The GNU linker by default sorts some sections by priority, so we
// do the same. We need to know that this might happen before we
// attach any input sections.
@@ -704,14 +690,46 @@ Layout::make_output_section(const char* name, elfcpp::Elf_Word type,
|| strcmp(name, ".fini_array") == 0))
os->set_may_sort_attached_input_sections();
+ // If we have already attached the sections to segments, then we
+ // need to attach this one now. This happens for sections created
+ // directly by the linker.
+ if (this->sections_are_attached_)
+ this->attach_section_to_segment(os);
+
return os;
}
+// Attach output sections to segments. This is called after we have
+// seen all the input sections.
+
+void
+Layout::attach_sections_to_segments()
+{
+ for (Section_list::iterator p = this->section_list_.begin();
+ p != this->section_list_.end();
+ ++p)
+ this->attach_section_to_segment(*p);
+
+ this->sections_are_attached_ = true;
+}
+
+// Attach an output section to a segment.
+
+void
+Layout::attach_section_to_segment(Output_section* os)
+{
+ if ((os->flags() & elfcpp::SHF_ALLOC) == 0)
+ this->unattached_section_list_.push_back(os);
+ else
+ this->attach_allocated_section_to_segment(os);
+}
+
// Attach an allocated output section to a segment.
void
-Layout::attach_to_segment(Output_section* os, elfcpp::Elf_Xword flags)
+Layout::attach_allocated_section_to_segment(Output_section* os)
{
+ elfcpp::Elf_Xword flags = os->flags();
gold_assert((flags & elfcpp::SHF_ALLOC) != 0);
if (parameters->options().relocatable())
@@ -811,58 +829,6 @@ Layout::make_output_section_for_script(const char* name)
return os;
}
-// We have to move an existing output section from the unallocated
-// list to the allocated list.
-
-void
-Layout::allocate_output_section(Output_section* os, elfcpp::Elf_Xword flags)
-{
- os->reset_address_and_file_offset();
-
- Section_list::iterator p = std::find(this->unattached_section_list_.begin(),
- this->unattached_section_list_.end(),
- os);
- gold_assert(p != this->unattached_section_list_.end());
- this->unattached_section_list_.erase(p);
-
- this->attach_to_segment(os, flags);
-}
-
-// We have to move an existing output section from the read-only
-// segment to the writable segment.
-
-void
-Layout::write_enable_output_section(Output_section* os,
- elfcpp::Elf_Xword flags)
-{
- gold_assert((os->flags() & elfcpp::SHF_WRITE) == 0);
- gold_assert(os->type() == elfcpp::SHT_PROGBITS);
- gold_assert((flags & elfcpp::SHF_WRITE) != 0);
- gold_assert((flags & elfcpp::SHF_ALLOC) != 0);
-
- if (parameters->options().relocatable())
- return;
-
- if (this->script_options_->saw_sections_clause())
- return;
-
- Segment_list::iterator p;
- for (p = this->segment_list_.begin();
- p != this->segment_list_.end();
- ++p)
- {
- if ((*p)->type() == elfcpp::PT_LOAD
- && ((*p)->flags() & elfcpp::PF_W) == 0)
- {
- (*p)->remove_output_section(os);
- break;
- }
- }
- gold_assert(p != this->segment_list_.end());
-
- this->attach_to_segment(os, flags);
-}
-
// Return the number of segments we expect to see.
size_t