Plugin interfaces to do Pettis Hansen style code layout in the gold linker.
Sriraman Tallam
tmsriram@google.com
Wed Jul 13 14:45:00 GMT 2011
Hi Ian,
I made all the changes you mentioned. I removed the
inspect_unclaimed_object hooks and allowed the functionality to happen
in claim_file hook, so one handle. Please look at readsyms.cc in
particular as that has the biggest change to allow this to happen.
Thanks,
-Sri.
* archive.cc (Archive::get_elf_object_for_member): Add extra parameter
to claim_file call.
* layout.cc (Layout::Layout): Initialize section_ordering_specified_,
input_section_position_, and input_section_glob_.
(read_layout_from_file): Call function section_ordering_specified.
* layout.h (is_section_ordering_specified): New function.
(section_ordering_specified): New function.
(section_ordering_specified_): New boolean member.
* main.cc(main): Call load_plugins after layout object is defined.
* output.cc (Output_section::add_input_section): Use
function section_ordering_specified to check if section ordering is
needed.
* output.cc (Output_section::add_relaxed_input_section): Use
function section_ordering_specified to check if section ordering is
needed.
(Output_section::update_section_layout): New function.
(Output_section::sort_attached_input_sections): Check if input section
must be reordered.
* output.h (Output_section::update_section_layout): New function.
* plugin.cc (get_section_count): New function.
(get_section_type): New function.
(get_section_name): New function.
(get_section_contents): New function.
(update_section_order): New function.
(allow_section_ordering): New function.
(Plugin::load): Add the new interfaces to the transfer vector.
(Plugin_manager::load_plugins): New parameter.
(Plugin_manager::all_symbols_read): New parameter.
(Plugin_manager::claim_file): New parameter. Save the elf object for
unclaimed objects.
(Plugin_manager::get_elf_object): New function.
* plugin.h (input_objects): New function
(Plugin__manager::load_plugins): New parameter.
(Plugin_manager::claim_file): New parameter.
(Plugin_manager::get_elf_object): New function.
(Plugin_manager::in_claim_file_handler): New function.
(Plugin_manager::in_claim_file_handler_): New member.
(layout): New function.
* readsyms.cc (Read_symbols::do_read_symbols): Call the claim_file
handler with an extra parameter. Make the elf object before calling
claim_file handler.
* testsuite/plugin_test.c (get_section_count): New function pointer.
(get_section_type): New function pointer.
(get_section_name): New function pointer.
(get_section_contents): New function pointer.
(update_section_order): New function pointer.
(allow_section_ordering): New function pointer.
(onload): Check if the new interfaces exist.
* plugin-api.h
(ld_plugin_section): New struct.
(ld_plugin_get_section_count): New typedef.
(ld_plugin_get_section_type): New typedef.
(ld_plugin_get_section_name): New typedef.
(ld_plugin_get_section_contents): New typedef.
(ld_plugin_update_section_order): New typedef.
(ld_plugin_allow_section_ordering): New typedef.
(LDPT_GET_SECTION_COUNT): New enum value.
(LDPT_GET_SECTION_TYPE): New enum value.
(LDPT_GET_SECTION_NAME): New enum value.
(LDPT_GET_SECTION_CONTENTS): New enum value.
(LDPT_UPDATE_SECTION_ORDER): New enum value.
(LDPT_ALLOW_SECTION_ORDERING): New enum value.
(tv_get_section_count): New struct members.
(tv_get_section_type): New struct members.
(tv_get_section_name): New struct members.
(tv_get_section_contents): New struct members.
(tv_update_section_order): New struct members.
(tv_allow_section_ordering): New struct members.
On Tue, Jul 5, 2011 at 2:29 PM, Ian Lance Taylor <iant@google.com> wrote:
> Sriraman Tallam <tmsriram@google.com> writes:
>
>> * layout.cc (Layout::Layout): Initialize section_ordering_specified_,
>> input_section_position_, and input_section_glob_.
>> (read_layout_from_file): Call function section_ordering_specified.
>> * layout.h (is_section_ordering_specified): New function.
>> (section_ordering_specified): New function.
>> (section_ordering_specified_): New boolean member.
>> * main.cc(main): Call load_plugins after layout object is defined.
>> * output.cc (Output_section::add_input_section): Use
>> function section_ordering_specified to check if section ordering is
>> needed.
>> * output.cc (Output_section::add_relaxed_input_section): Use
>> function section_ordering_specified to check if section ordering is
>> needed.
>> (Output_section::update_section_layout): New function.
>> (Output_section::sort_attached_input_sections): Check if input section
>> must be reordered.
>> * output.h (Output_section::update_section_layout): New function.
>> * plugin.cc (register_inspect_unclaimed_object): New function.
>> (get_section_count): New function.
>> (get_section_type): New function.
>> (get_section_name): New function.
>> (get_section_contents): New function.
>> (update_section_order): New function.
>> (allow_section_ordering): New function.
>> (Plugin::inspect_unclaimed_object): New function.
>> (Plugin_manager::inspect_unclaimed_object): New function.
>> (Plugin_manager::get_unclaimed_object): New function.
>> (Plugin::load): Add the new interfaces to the transfer vector.
>> (Plugin_manager::load_plugins): New parameter.
>> (Plugin_manager::all_symbols_read): New parameter.
>> * plugin.h (input_objects): New function
>> (Plugin::inspect_unclaimed_object): New function.
>> (Plugin::set_inspect_unclaimed_object_handler): New function.
>> (Plugin__manager::load_plugins): New parameter.
>> (Plugin_manager::inspect_unclaimed_object): New function.
>> (Plugin_manager::get_unclaimed_object): New function.
>> (Plugin_manager::in_inspect_unclaimed_object_handler): New function.
>> (Plugin_manager::set_inspect_unclaimed_object_handler): New function.
>> (Plugin_manager::unclaimed_object): New function.
>> (Plugin_manager::Unclaimed_object_list): New typedef.
>> (Plugin_manager::unclaimed_objects_): New member.
>> (Plugin_manager::in_inspect_unclaimed_object_handler_): New member.
>> (layout): New function.
>> * readsyms.cc (Read_symbols::do_read_symbols): Call the plugin handler.
>> * testsuite/plugin_test.c (register_inspect_unclaimed_object_hook):
>> New function pointer.
>> (get_section_count): New function pointer.
>> (get_section_type): New function pointer.
>> (get_section_name): New function pointer.
>> (get_section_contents): New function pointer.
>> (update_section_order): New function pointer.
>> (allow_section_ordering): New function pointer.
>> (inspect_unclaimed_object_hook): New function.
>> (onload): Check if the new interfaces exist.
>> * plugin-api.h
>> (unclaimed_obkect_handle): New typedef.
>> (ld_plugin_section): New struct.
>> (ld_plugin_inspect_unclaimed_object_handler): New typedef.
>> (ld_plugin_register_inspect_unclaimed_object): New typedef.
>> (ld_plugin_get_section_count): New typedef.
>> (ld_plugin_get_section_type): New typedef.
>> (ld_plugin_get_section_name): New typedef.
>> (ld_plugin_get_section_contents): New typedef.
>> (ld_plugin_update_section_order): New typedef.
>> (ld_plugin_allow_section_ordering): New typedef.
>> (LDPT_REGISTER_INSPECT_UNCLAIMED_OBJECT_HOOK): New enum value.
>> (LDPT_GET_SECTION_COUNT): New enum value.
>> (LDPT_GET_SECTION_TYPE): New enum value.
>> (LDPT_GET_SECTION_NAME): New enum value.
>> (LDPT_GET_SECTION_CONTENTS): New enum value.
>> (LDPT_UPDATE_SECTION_ORDER): New enum value.
>> (LDPT_ALLOW_SECTION_ORDERING): New enum value.
>> (tv_get_section_count): New struct members.
>> (tv_get_section_type): New struct members.
>> (tv_get_section_name): New struct members.
>> (tv_get_section_contents): New struct members.
>> (tv_update_section_order): New struct members.
>> (tv_allow_section_ordering): New struct members.
>
>
>> +static enum ld_plugin_status
>> +get_input_section_contents(const struct ld_plugin_section section,
>> + const unsigned char** section_contents,
>> + unsigned int* len);
>
> Let's change the len parameter from "unsigned int*" to "size_t*".
>
>
>> +// This updates the section order index of input sections according to the
>> +// the order specified in the mapping from Section id to order index.
>> +
>> +void
>> +Output_section::update_section_layout(
>> + const Section_layout_order& order_map)
>> +{
>> + for (Input_section_list::iterator p = this->input_sections_.begin();
>> + p != this->input_sections_.end();
>> + ++p)
>> + {
>> + if ((*p).is_input_section()
>> + || (*p).is_relaxed_input_section())
>> + {
>> + Object* obj = ((*p).is_input_section()
>> + ? (*p).relobj()
>> + : (*p).relaxed_input_section()->relobj());
>> + unsigned int shndx = (*p).shndx();
>> + Section_layout_order::const_iterator it
>> + = order_map.find(Section_id(obj, shndx));
>> + if (it == order_map.end())
>> + continue;
>> + unsigned int section_order_index = it->second;
>> + if (section_order_index != 0)
>> + {
>> + (*p).set_section_order_index(section_order_index);
>> + this->set_input_section_order_specified();
>> + }
>> + }
>> + }
>> +}
>
> Please write "p->" instead of "(*p).".
>
>
>> +// Specify the ordering of sections in the final layout. The sections are
>> +// specified as (handle,shndx) pairs in the two arrays in the order in
>> +// which they should appear in the final layout.
>> +
>> +static enum ld_plugin_status
>> +update_section_order(const struct ld_plugin_section *section_list,
>> + unsigned int num_sections)
>> +{
>> + gold_assert(parameters->options().has_plugins());
>> +
>> + if (num_sections == 0)
>> + return LDPS_OK;
>> +
>> + if (section_list == NULL)
>> + return LDPS_ERR;
>> +
>> + std::map<Section_id, unsigned int> order_map;
>> +
>> + for (unsigned int i = 0; i < num_sections; ++i)
>> + {
>> + Object* obj = parameters->options().plugins()->get_unclaimed_object(
>> + section_list[i].handle);
>> + unsigned int shndx = section_list[i].shndx;
>> + Section_id secn_id(obj, shndx);
>> + order_map[secn_id] = i + 1;
>> + }
>> +
>> + Layout* layout = parameters->options().plugins()->layout();
>> + gold_assert (layout != NULL);
>> +
>> + for (Layout::Section_list::const_iterator p = layout->section_list().begin();
>> + p != layout->section_list().end();
>> + ++p)
>> + (*p)->update_section_layout(order_map);
>> +
>> + return LDPS_OK;
>> +}
>
> You need to check the return value of get_unclaimed_object, and return
> LDPS_ERR if it returns NULL.
>
>
>> + // Allow the plugins to inspect the unclaimed object now.
>> + if (parameters->options().has_plugins())
>> + parameters->options().plugins()->inspect_unclaimed_object(obj);
>
> Can you remind me of why we need both inspect_unclaimed_object and
> claim_file? To me it seems that it might be logical to let claim_file
> call get_section_count and so forth, and even update_section_order, and
> then simply set *claimed to 0 if it doesn't want to claim the file.
>
>
>> +/* The linker's interface for retrieving the name of specific section in
>> + an object. This interface should only be invoked in the
>> + inspect_unclaimed_object handler. This function sets *SECTION_NAME_PTR
>> + to a null-terminated buffer allocated by malloc. The plugin must free
>> + *SECTION_NAME_PTR. */
>
> s/of specific section/of a specific section/
>
>
>> +/* The linker's interface for retrieving the contents of a specific section
>> + in an object. This interface should only be invoked in the
>> + inspect_unclaimed_object handler. This function sets *SECTION_CONTENTS to
>> + point to a buffer that is valid until inspect_unclaimed_object handler
>> + returns. It sets *LEN to the size of the buffer. */
>
> There seems to be an extra space after "valid".
>
>
> The only important point in the above is whether we can eliminate
> inspect_unclaimed_object.
>
> Ian
>
-------------- next part --------------
Index: include/plugin-api.h
===================================================================
RCS file: /cvs/src/src/include/plugin-api.h,v
retrieving revision 1.14
diff -u -u -p -r1.14 plugin-api.h
--- include/plugin-api.h 23 Mar 2011 14:09:48 -0000 1.14
+++ include/plugin-api.h 13 Jul 2011 01:32:36 -0000
@@ -93,6 +93,14 @@ struct ld_plugin_symbol
int resolution;
};
+/* An object's section. */
+
+struct ld_plugin_section
+{
+ const void* handle;
+ unsigned int shndx;
+};
+
/* Whether the symbol is a definition, reference, or common, weak or not. */
enum ld_plugin_symbol_kind
@@ -244,6 +252,66 @@ typedef
enum ld_plugin_status
(*ld_plugin_message) (int level, const char *format, ...);
+/* The linker's interface for retrieving the number of sections in an object.
+ The handle is obtained in the claim_file handler. This interface should
+ only be invoked in the claim_file handler. This function sets *COUNT to
+ the number of sections in the object. */
+
+typedef
+enum ld_plugin_status
+(*ld_plugin_get_input_section_count) (const void* handle, unsigned int *count);
+
+/* The linker's interface for retrieving the section type of a specific
+ section in an object. This interface should only be invoked in the
+ claim_file handler. This function sets *TYPE to an ELF SHT_xxx value. */
+
+typedef
+enum ld_plugin_status
+(*ld_plugin_get_input_section_type) (const struct ld_plugin_section section,
+ unsigned int *type);
+
+/* The linker's interface for retrieving the name of a specific section in
+ an object. This interface should only be invoked in the claim_file handler.
+ This function sets *SECTION_NAME_PTR to a null-terminated buffer allocated
+ by malloc. The plugin must free *SECTION_NAME_PTR. */
+
+typedef
+enum ld_plugin_status
+(*ld_plugin_get_input_section_name) (const struct ld_plugin_section section,
+ char **section_name_ptr);
+
+/* The linker's interface for retrieving the contents of a specific section
+ in an object. This interface should only be invoked in the claim_file
+ handler. This function sets *SECTION_CONTENTS to point to a buffer that is
+ valid until inspect_unclaimed_object handler returns. It sets *LEN to the
+ size of the buffer. */
+
+typedef
+enum ld_plugin_status
+(*ld_plugin_get_input_section_contents) (const struct ld_plugin_section section,
+ const unsigned char **section_contents,
+ size_t* len);
+
+/* The linker's interface for specifying the desired order of sections.
+ The sections should be specifed using the array SECTION_LIST in the
+ order in which they should appear in the final layout. NUM_SECTIONS
+ specifies the number of entries in each array. This should be invoked
+ in the all_symbols_read handler. */
+
+typedef
+enum ld_plugin_status
+(*ld_plugin_update_section_order) (const struct ld_plugin_section *section_list,
+ unsigned int num_sections);
+
+/* The linker's interface for specifying that reordering of sections is
+ desired so that the linker can prepare for it. This should be invoked
+ before update_section_order, preferably in the inspect_unclaimed_object
+ handler. */
+
+typedef
+enum ld_plugin_status
+(*ld_plugin_allow_section_ordering) (void);
+
enum ld_plugin_level
{
LDPL_INFO,
@@ -274,7 +342,13 @@ enum ld_plugin_tag
LDPT_OUTPUT_NAME,
LDPT_SET_EXTRA_LIBRARY_PATH,
LDPT_GNU_LD_VERSION,
- LDPT_GET_VIEW
+ LDPT_GET_VIEW,
+ LDPT_GET_INPUT_SECTION_COUNT,
+ LDPT_GET_INPUT_SECTION_TYPE,
+ LDPT_GET_INPUT_SECTION_NAME,
+ LDPT_GET_INPUT_SECTION_CONTENTS,
+ LDPT_UPDATE_SECTION_ORDER,
+ LDPT_ALLOW_SECTION_ORDERING
};
/* The plugin transfer vector. */
@@ -298,6 +372,12 @@ struct ld_plugin_tv
ld_plugin_release_input_file tv_release_input_file;
ld_plugin_add_input_library tv_add_input_library;
ld_plugin_set_extra_library_path tv_set_extra_library_path;
+ ld_plugin_get_input_section_count tv_get_input_section_count;
+ ld_plugin_get_input_section_type tv_get_input_section_type;
+ ld_plugin_get_input_section_name tv_get_input_section_name;
+ ld_plugin_get_input_section_contents tv_get_input_section_contents;
+ ld_plugin_update_section_order tv_update_section_order;
+ ld_plugin_allow_section_ordering tv_allow_section_ordering;
} tv_u;
};
Index: gold/archive.cc
===================================================================
RCS file: /cvs/src/src/gold/archive.cc,v
retrieving revision 1.69
diff -u -u -p -r1.69 archive.cc
--- gold/archive.cc 2 Jun 2011 20:13:23 -0000 1.69
+++ gold/archive.cc 13 Jul 2011 01:32:37 -0000
@@ -653,7 +653,8 @@ Archive::get_elf_object_for_member(off_t
{
Object* obj = parameters->options().plugins()->claim_file(input_file,
memoff,
- memsize);
+ memsize,
+ NULL);
if (obj != NULL)
{
// The input file was claimed by a plugin, and its symbols
Index: gold/layout.cc
===================================================================
RCS file: /cvs/src/src/gold/layout.cc,v
retrieving revision 1.215
diff -u -u -p -r1.215 layout.cc
--- gold/layout.cc 11 Jul 2011 16:19:50 -0000 1.215
+++ gold/layout.cc 13 Jul 2011 01:32:37 -0000
@@ -399,11 +399,14 @@ Layout::Layout(int number_of_input_files
any_postprocessing_sections_(false),
resized_signatures_(false),
have_stabstr_section_(false),
+ section_ordering_specified_(false),
incremental_inputs_(NULL),
record_output_section_data_from_script_(false),
script_output_section_data_list_(),
segment_states_(NULL),
relaxation_debug_check_(NULL),
+ input_section_position_(),
+ input_section_glob_(),
incremental_base_(NULL),
free_list_()
{
@@ -2209,7 +2212,7 @@ Layout::find_section_order_index(const s
}
// Read the sequence of input sections from the file specified with
-// --section-ordering-file.
+// option --section-ordering-file.
void
Layout::read_layout_from_file()
@@ -2225,6 +2228,7 @@ Layout::read_layout_from_file()
std::getline(in, line); // this chops off the trailing \n, if any
unsigned int position = 1;
+ this->set_section_ordering_specified();
while (in)
{
Index: gold/layout.h
===================================================================
RCS file: /cvs/src/src/gold/layout.h,v
retrieving revision 1.97
diff -u -u -p -r1.97 layout.h
--- gold/layout.h 1 Jul 2011 22:05:01 -0000 1.97
+++ gold/layout.h 13 Jul 2011 01:32:37 -0000
@@ -492,6 +492,14 @@ class Layout
const char* name, const elfcpp::Shdr<size, big_endian>& shdr,
unsigned int reloc_shndx, unsigned int reloc_type, off_t* offset);
+ bool
+ is_section_ordering_specified()
+ { return this->section_ordering_specified_; }
+
+ void
+ set_section_ordering_specified()
+ { this->section_ordering_specified_ = true; }
+
// For incremental updates, allocate a block of memory from the
// free list. Find a block starting at or after MINOFF.
off_t
@@ -501,6 +509,8 @@ class Layout
unsigned int
find_section_order_index(const std::string&);
+ // Read the sequence of input sections from the file specified with
+ // linker option --section-ordering-file.
void
read_layout_from_file();
@@ -1262,6 +1272,9 @@ class Layout
bool resized_signatures_;
// Whether we have created a .stab*str output section.
bool have_stabstr_section_;
+ // True if the input sections in the output sections should be sorted
+ // as specified in a section ordering file.
+ bool section_ordering_specified_;
// In incremental build, holds information check the inputs and build the
// .gnu_incremental_inputs section.
Incremental_inputs* incremental_inputs_;
Index: gold/main.cc
===================================================================
RCS file: /cvs/src/src/gold/main.cc,v
retrieving revision 1.44
diff -u -u -p -r1.44 main.cc
--- gold/main.cc 8 Jun 2011 04:43:28 -0000 1.44
+++ gold/main.cc 13 Jul 2011 01:32:37 -0000
@@ -195,10 +195,6 @@ main(int argc, char** argv)
if (parameters->options().relocatable())
command_line.script_options().version_script_info()->clear();
- // Load plugin libraries.
- if (command_line.options().has_plugins())
- command_line.options().plugins()->load_plugins();
-
// The work queue.
Workqueue workqueue(command_line.options());
@@ -234,6 +230,10 @@ main(int argc, char** argv)
if (parameters->options().section_ordering_file())
layout.read_layout_from_file();
+ // Load plugin libraries.
+ if (command_line.options().has_plugins())
+ command_line.options().plugins()->load_plugins(&layout);
+
// Get the search path from the -L options.
Dirsearch search_path;
search_path.initialize(&workqueue, &command_line.options().library_path());
Index: gold/output.cc
===================================================================
RCS file: /cvs/src/src/gold/output.cc,v
retrieving revision 1.155
diff -u -u -p -r1.155 output.cc
--- gold/output.cc 8 Jul 2011 22:48:08 -0000 1.155
+++ gold/output.cc 13 Jul 2011 01:32:38 -0000
@@ -2296,7 +2296,7 @@ Output_section::add_input_section(Layout
&& (sh_flags & elfcpp::SHF_EXECINSTR) != 0
&& parameters->target().has_code_fill()
&& (parameters->target().may_relax()
- || parameters->options().section_ordering_file()))
+ || layout->is_section_ordering_specified()))
{
gold_assert(this->fills_.empty());
this->generate_code_fills_at_write_ = true;
@@ -2335,10 +2335,10 @@ Output_section::add_input_section(Layout
|| this->must_sort_attached_input_sections()
|| parameters->options().user_set_Map()
|| parameters->target().may_relax()
- || parameters->options().section_ordering_file())
+ || layout->is_section_ordering_specified())
{
Input_section isecn(object, shndx, input_section_size, addralign);
- if (parameters->options().section_ordering_file())
+ if (layout->is_section_ordering_specified())
{
unsigned int section_order_index =
layout->find_section_order_index(std::string(secname));
@@ -2421,7 +2421,7 @@ Output_section::add_relaxed_input_sectio
// If the --section-ordering-file option is used to specify the order of
// sections, we need to keep track of sections.
- if (parameters->options().section_ordering_file())
+ if (layout->is_section_ordering_specified())
{
unsigned int section_order_index =
layout->find_section_order_index(name);
@@ -3339,6 +3339,38 @@ Output_section::Input_section_sort_secti
return s1_secn_index < s2_secn_index;
}
+// This updates the section order index of input sections according to the
+// the order specified in the mapping from Section id to order index.
+
+void
+Output_section::update_section_layout(
+ const Section_layout_order& order_map)
+{
+ for (Input_section_list::iterator p = this->input_sections_.begin();
+ p != this->input_sections_.end();
+ ++p)
+ {
+ if (p->is_input_section()
+ || p->is_relaxed_input_section())
+ {
+ Object* obj = (p->is_input_section()
+ ? p->relobj()
+ : p->relaxed_input_section()->relobj());
+ unsigned int shndx = p->shndx();
+ Section_layout_order::const_iterator it
+ = order_map.find(Section_id(obj, shndx));
+ if (it == order_map.end())
+ continue;
+ unsigned int section_order_index = it->second;
+ if (section_order_index != 0)
+ {
+ p->set_section_order_index(section_order_index);
+ this->set_input_section_order_specified();
+ }
+ }
+ }
+}
+
// Sort the input sections attached to an output section.
void
@@ -3381,7 +3413,7 @@ Output_section::sort_attached_input_sect
}
else
{
- gold_assert(parameters->options().section_ordering_file());
+ gold_assert(this->input_section_order_specified());
std::sort(sort_list.begin(), sort_list.end(),
Input_section_sort_section_order_index_compare());
}
Index: gold/output.h
===================================================================
RCS file: /cvs/src/src/gold/output.h,v
retrieving revision 1.126
diff -u -u -p -r1.126 output.h
--- gold/output.h 6 Jul 2011 21:19:32 -0000 1.126
+++ gold/output.h 13 Jul 2011 01:32:38 -0000
@@ -2665,6 +2665,11 @@ class Output_section : public Output_dat
flags() const
{ return this->flags_; }
+ typedef std::map<Section_id, unsigned int> Section_layout_order;
+
+ void
+ update_section_layout(const Section_layout_order& order_map);
+
// Update the output section flags based on input section flags.
void
update_flags_for_input_section(elfcpp::Elf_Xword flags);
Index: gold/plugin.cc
===================================================================
RCS file: /cvs/src/src/gold/plugin.cc,v
retrieving revision 1.47
diff -u -u -p -r1.47 plugin.cc
--- gold/plugin.cc 25 May 2011 00:17:47 -0000 1.47
+++ gold/plugin.cc 13 Jul 2011 01:32:38 -0000
@@ -89,6 +89,29 @@ set_extra_library_path(const char *path)
static enum ld_plugin_status
message(int level, const char *format, ...);
+static enum ld_plugin_status
+get_input_section_count(const void* handle, unsigned int* count);
+
+static enum ld_plugin_status
+get_input_section_type(const struct ld_plugin_section section,
+ unsigned int* type);
+
+static enum ld_plugin_status
+get_input_section_name(const struct ld_plugin_section section,
+ char** section_name_ptr);
+
+static enum ld_plugin_status
+get_input_section_contents(const struct ld_plugin_section section,
+ const unsigned char** section_contents,
+ size_t* len);
+
+static enum ld_plugin_status
+update_section_order(const struct ld_plugin_section *section_list,
+ unsigned int num_sections);
+
+static enum ld_plugin_status
+allow_section_ordering();
+
};
#endif // ENABLE_PLUGINS
@@ -133,7 +156,8 @@ Plugin::load()
sscanf(ver, "%d.%d", &major, &minor);
// Allocate and populate a transfer vector.
- const int tv_fixed_size = 17;
+ const int tv_fixed_size = 23;
+
int tv_size = this->args_.size() + tv_fixed_size;
ld_plugin_tv* tv = new ld_plugin_tv[tv_size];
@@ -216,6 +240,30 @@ Plugin::load()
tv[i].tv_u.tv_set_extra_library_path = set_extra_library_path;
++i;
+ tv[i].tv_tag = LDPT_GET_INPUT_SECTION_COUNT;
+ tv[i].tv_u.tv_get_input_section_count = get_input_section_count;
+
+ ++i;
+ tv[i].tv_tag = LDPT_GET_INPUT_SECTION_TYPE;
+ tv[i].tv_u.tv_get_input_section_type = get_input_section_type;
+
+ ++i;
+ tv[i].tv_tag = LDPT_GET_INPUT_SECTION_NAME;
+ tv[i].tv_u.tv_get_input_section_name = get_input_section_name;
+
+ ++i;
+ tv[i].tv_tag = LDPT_GET_INPUT_SECTION_CONTENTS;
+ tv[i].tv_u.tv_get_input_section_contents = get_input_section_contents;
+
+ ++i;
+ tv[i].tv_tag = LDPT_UPDATE_SECTION_ORDER;
+ tv[i].tv_u.tv_update_section_order = update_section_order;
+
+ ++i;
+ tv[i].tv_tag = LDPT_ALLOW_SECTION_ORDERING;
+ tv[i].tv_u.tv_allow_section_ordering = allow_section_ordering;
+
+ ++i;
tv[i].tv_tag = LDPT_NULL;
tv[i].tv_u.tv_val = 0;
@@ -326,8 +374,9 @@ Plugin_manager::~Plugin_manager()
// Load all plugin libraries.
void
-Plugin_manager::load_plugins()
+Plugin_manager::load_plugins(Layout* layout)
{
+ this->layout_ = layout;
for (this->current_ = this->plugins_.begin();
this->current_ != this->plugins_.end();
++this->current_)
@@ -338,7 +387,7 @@ Plugin_manager::load_plugins()
Pluginobj*
Plugin_manager::claim_file(Input_file* input_file, off_t offset,
- off_t filesize)
+ off_t filesize, Object* elf_object)
{
if (this->in_replacement_phase_)
return NULL;
@@ -350,6 +399,9 @@ Plugin_manager::claim_file(Input_file* i
this->plugin_input_file_.offset = offset;
this->plugin_input_file_.filesize = filesize;
this->plugin_input_file_.handle = reinterpret_cast<void*>(handle);
+ if (elf_object != NULL)
+ this->objects_.push_back(elf_object);
+ this->in_claim_file_handler_ = true;
for (this->current_ = this->plugins_.begin();
this->current_ != this->plugins_.end();
@@ -358,9 +410,11 @@ Plugin_manager::claim_file(Input_file* i
if ((*this->current_)->claim_file(&this->plugin_input_file_))
{
this->any_claimed_ = true;
+ this->in_claim_file_handler_ = false;
- if (this->objects_.size() > handle)
- return this->objects_[handle];
+ if (this->objects_.size() > handle
+ && this->objects_[handle]->pluginobj() != NULL)
+ return this->objects_[handle]->pluginobj();
// If the plugin claimed the file but did not call the
// add_symbols callback, we need to create the Pluginobj now.
@@ -369,6 +423,7 @@ Plugin_manager::claim_file(Input_file* i
}
}
+ this->in_claim_file_handler_ = false;
return NULL;
}
@@ -402,7 +457,7 @@ Plugin_manager::save_input_group(Input_g
void
Plugin_manager::all_symbols_read(Workqueue* workqueue, Task* task,
Input_objects* input_objects,
- Symbol_table* symtab, Layout* layout,
+ Symbol_table* symtab,
Dirsearch* dirpath, Mapfile* mapfile,
Task_token** last_blocker)
{
@@ -411,7 +466,6 @@ Plugin_manager::all_symbols_read(Workque
this->task_ = task;
this->input_objects_ = input_objects;
this->symtab_ = symtab;
- this->layout_ = layout;
this->dirpath_ = dirpath;
this->mapfile_ = mapfile;
this->this_blocker_ = NULL;
@@ -599,12 +653,20 @@ Pluginobj*
Plugin_manager::make_plugin_object(unsigned int handle)
{
// Make sure we aren't asked to make an object for the same handle twice.
- if (this->objects_.size() != handle)
+ if (this->objects_.size() != handle
+ && this->objects_[handle]->pluginobj() != NULL)
return NULL;
Pluginobj* obj = make_sized_plugin_object(this->input_file_,
this->plugin_input_file_.offset,
this->plugin_input_file_.filesize);
+
+
+ // If the elf object for this file was pushed into the objects_ vector, delete
+ // it to make room for the Pluginobj as this file is claimed.
+ if (this->objects_.size() != handle)
+ this->objects_.pop_back();
+
this->objects_.push_back(obj);
return obj;
}
@@ -616,7 +678,7 @@ ld_plugin_status
Plugin_manager::get_input_file(unsigned int handle,
struct ld_plugin_input_file* file)
{
- Pluginobj* obj = this->object(handle);
+ Pluginobj* obj = this->object(handle)->pluginobj();
if (obj == NULL)
return LDPS_BAD_HANDLE;
@@ -634,7 +696,7 @@ Plugin_manager::get_input_file(unsigned
ld_plugin_status
Plugin_manager::release_input_file(unsigned int handle)
{
- Pluginobj* obj = this->object(handle);
+ Pluginobj* obj = this->object(handle)->pluginobj();
if (obj == NULL)
return LDPS_BAD_HANDLE;
@@ -642,6 +704,23 @@ Plugin_manager::release_input_file(unsig
return LDPS_OK;
}
+// Get the elf object corresponding to the handle. Return NULL if we
+// found a Pluginobj instead.
+
+Object*
+Plugin_manager::get_elf_object(const void* handle)
+{
+ Object* obj = parameters->options().plugins()->object(
+ static_cast<unsigned int>(reinterpret_cast<intptr_t>(handle)));
+
+ // The object should not be a Pluginobj.
+ if (obj == NULL
+ || obj->pluginobj() != NULL)
+ return NULL;
+
+ return obj;
+}
+
ld_plugin_status
Plugin_manager::get_view(unsigned int handle, const void **viewp)
{
@@ -659,7 +738,7 @@ Plugin_manager::get_view(unsigned int ha
else
{
// An already claimed file.
- Pluginobj* obj = this->object(handle);
+ Pluginobj* obj = this->object(handle)->pluginobj();
if (obj == NULL)
return LDPS_BAD_HANDLE;
offset = obj->offset();
@@ -1226,7 +1305,6 @@ Plugin_hook::run(Workqueue* workqueue)
this,
this->input_objects_,
this->symtab_,
- this->layout_,
this->dirpath_,
this->mapfile_,
&this->this_blocker_);
@@ -1321,7 +1399,7 @@ get_symbols(const void* handle, int nsym
{
gold_assert(parameters->options().has_plugins());
Pluginobj* obj = parameters->options().plugins()->object(
- static_cast<unsigned int>(reinterpret_cast<intptr_t>(handle)));
+ static_cast<unsigned int>(reinterpret_cast<intptr_t>(handle)))->pluginobj();
if (obj == NULL)
return LDPS_ERR;
return obj->get_symbol_resolution_info(nsyms, syms);
@@ -1384,6 +1462,160 @@ message(int level, const char* format, .
return LDPS_OK;
}
+// Get the section count of the object corresponding to the handle. This
+// plugin interface can only be called in the claim_file handler of the plugin.
+
+static enum ld_plugin_status
+get_input_section_count(const void* handle, unsigned int* count)
+{
+ gold_assert(parameters->options().has_plugins());
+
+ if (!parameters->options().plugins()->in_claim_file_handler())
+ return LDPS_ERR;
+
+ Object* obj = parameters->options().plugins()->get_elf_object(handle);
+
+ if (obj == NULL)
+ return LDPS_ERR;
+
+ *count = obj->shnum();
+ return LDPS_OK;
+}
+
+// Get the type of the specified section in the object corresponding
+// to the handle. This plugin interface can only be called in the
+// claim_file handler of the plugin.
+
+static enum ld_plugin_status
+get_input_section_type(const struct ld_plugin_section section,
+ unsigned int* type)
+{
+ gold_assert(parameters->options().has_plugins());
+
+ if (!parameters->options().plugins()->in_claim_file_handler())
+ return LDPS_ERR;
+
+ Object* obj
+ = parameters->options().plugins()->get_elf_object(section.handle);
+
+ if (obj == NULL)
+ return LDPS_BAD_HANDLE;
+
+ *type = obj->section_type(section.shndx);
+ return LDPS_OK;
+}
+
+// Get the name of the specified section in the object corresponding
+// to the handle. This plugin interface can only be called in the
+// claim_file handler of the plugin.
+
+static enum ld_plugin_status
+get_input_section_name(const struct ld_plugin_section section,
+ char** section_name_ptr)
+{
+ gold_assert(parameters->options().has_plugins());
+
+ if (!parameters->options().plugins()->in_claim_file_handler())
+ return LDPS_ERR;
+
+ Object* obj
+ = parameters->options().plugins()->get_elf_object(section.handle);
+
+ if (obj == NULL)
+ return LDPS_BAD_HANDLE;
+
+ // Check if the object is locked before getting the section name.
+ gold_assert(obj->is_locked());
+
+ const std::string section_name = obj->section_name(section.shndx);
+ const char* section_name_c_ptr = section_name.c_str();
+ *section_name_ptr
+ = static_cast<char*>(malloc(strlen(section_name_c_ptr) + 1));
+ strcpy(*section_name_ptr, section_name_c_ptr);
+ return LDPS_OK;
+}
+
+// Get the contents of the specified section in the object corresponding
+// to the handle. This plugin interface can only be called in the
+// claim_file handler of the plugin.
+
+static enum ld_plugin_status
+get_input_section_contents(const struct ld_plugin_section section,
+ const unsigned char** section_contents_ptr,
+ size_t* len)
+{
+ gold_assert(parameters->options().has_plugins());
+
+ if (!parameters->options().plugins()->in_claim_file_handler())
+ return LDPS_ERR;
+
+ Object* obj
+ = parameters->options().plugins()->get_elf_object(section.handle);
+
+ if (obj == NULL)
+ return LDPS_BAD_HANDLE;
+
+ // Check if the object is locked before getting the section contents.
+ gold_assert(obj->is_locked());
+
+ section_size_type plen;
+ *section_contents_ptr
+ = obj->section_contents(section.shndx, &plen, false);
+ *len = plen;
+ return LDPS_OK;
+}
+
+// Specify the ordering of sections in the final layout. The sections are
+// specified as (handle,shndx) pairs in the two arrays in the order in
+// which they should appear in the final layout.
+
+static enum ld_plugin_status
+update_section_order(const struct ld_plugin_section *section_list,
+ unsigned int num_sections)
+{
+ gold_assert(parameters->options().has_plugins());
+
+ if (num_sections == 0)
+ return LDPS_OK;
+
+ if (section_list == NULL)
+ return LDPS_ERR;
+
+ std::map<Section_id, unsigned int> order_map;
+
+ for (unsigned int i = 0; i < num_sections; ++i)
+ {
+ Object* obj = parameters->options().plugins()->get_elf_object(
+ section_list[i].handle);
+ if (obj == NULL)
+ return LDPS_BAD_HANDLE;
+ unsigned int shndx = section_list[i].shndx;
+ Section_id secn_id(obj, shndx);
+ order_map[secn_id] = i + 1;
+ }
+
+ Layout* layout = parameters->options().plugins()->layout();
+ gold_assert (layout != NULL);
+
+ for (Layout::Section_list::const_iterator p = layout->section_list().begin();
+ p != layout->section_list().end();
+ ++p)
+ (*p)->update_section_layout(order_map);
+
+ return LDPS_OK;
+}
+
+// Let the linker know that the sections could be reordered.
+
+static enum ld_plugin_status
+allow_section_ordering()
+{
+ gold_assert(parameters->options().has_plugins());
+ Layout* layout = parameters->options().plugins()->layout();
+ layout->set_section_ordering_specified();
+ return LDPS_OK;
+}
+
#endif // ENABLE_PLUGINS
// Allocate a Pluginobj object of the appropriate size and endianness.
Index: gold/plugin.h
===================================================================
RCS file: /cvs/src/src/gold/plugin.h,v
retrieving revision 1.19
diff -u -u -p -r1.19 plugin.h
--- gold/plugin.h 12 Apr 2011 00:44:48 -0000 1.19
+++ gold/plugin.h 13 Jul 2011 01:32:38 -0000
@@ -131,6 +131,7 @@ class Plugin_manager
: plugins_(), objects_(), deferred_layout_objects_(), input_file_(NULL),
plugin_input_file_(), rescannable_(), undefined_symbols_(),
any_claimed_(false), in_replacement_phase_(false), any_added_(false),
+ in_claim_file_handler_(false),
options_(options), workqueue_(NULL), task_(NULL), input_objects_(NULL),
symtab_(NULL), layout_(NULL), dirpath_(NULL), mapfile_(NULL),
this_blocker_(NULL), extra_search_path_()
@@ -153,11 +154,22 @@ class Plugin_manager
// Load all plugin libraries.
void
- load_plugins();
+ load_plugins(Layout* layout);
// Call the plugin claim-file handlers in turn to see if any claim the file.
Pluginobj*
- claim_file(Input_file* input_file, off_t offset, off_t filesize);
+ claim_file(Input_file* input_file, off_t offset, off_t filesize,
+ Object* elf_object);
+
+ // Get the object associated with the handle and check if it is an elf object.
+ // If it is not a Pluginobj, it is an elf object.
+ Object*
+ get_elf_object(const void* handle);
+
+ // True if the claim_file handler of the plugins is being called.
+ bool
+ in_claim_file_handler()
+ { return in_claim_file_handler_; }
// Let the plugin manager save an archive for later rescanning.
// This takes ownership of the Archive pointer.
@@ -173,7 +185,7 @@ class Plugin_manager
void
all_symbols_read(Workqueue* workqueue, Task* task,
Input_objects* input_objects, Symbol_table* symtab,
- Layout* layout, Dirsearch* dirpath, Mapfile* mapfile,
+ Dirsearch* dirpath, Mapfile* mapfile,
Task_token** last_blocker);
// Tell the plugin manager that we've a new undefined symbol which
@@ -219,7 +231,7 @@ class Plugin_manager
make_plugin_object(unsigned int handle);
// Return the Pluginobj associated with the given HANDLE.
- Pluginobj*
+ Object*
object(unsigned int handle) const
{
if (handle >= this->objects_.size())
@@ -265,6 +277,14 @@ class Plugin_manager
in_replacement_phase() const
{ return this->in_replacement_phase_; }
+ Input_objects*
+ input_objects() const
+ { return this->input_objects_; }
+
+ Layout*
+ layout()
+ { return this->layout_; }
+
private:
Plugin_manager(const Plugin_manager&);
Plugin_manager& operator=(const Plugin_manager&);
@@ -293,7 +313,7 @@ class Plugin_manager
};
typedef std::list<Plugin*> Plugin_list;
- typedef std::vector<Pluginobj*> Object_list;
+ typedef std::vector<Object*> Object_list;
typedef std::vector<Relobj*> Deferred_layout_list;
typedef std::vector<Rescannable> Rescannable_list;
typedef std::vector<Symbol*> Undefined_symbol_list;
@@ -340,6 +360,9 @@ class Plugin_manager
// Whether any input files or libraries were added by a plugin.
bool any_added_;
+ // Set to true when the claim_file handler of a plugin is called.
+ bool in_claim_file_handler_;
+
const General_options& options_;
Workqueue* workqueue_;
Task* task_;
Index: gold/readsyms.cc
===================================================================
RCS file: /cvs/src/src/gold/readsyms.cc,v
retrieving revision 1.50
diff -u -u -p -r1.50 readsyms.cc
--- gold/readsyms.cc 6 Jul 2011 22:07:59 -0000 1.50
+++ gold/readsyms.cc 13 Jul 2011 01:32:38 -0000
@@ -320,12 +320,33 @@ Read_symbols::do_read_symbols(Workqueue*
}
}
+ Object* elf_obj = NULL;
+ bool unconfigured;
+ bool* punconfigured = NULL;
+ if (is_elf)
+ {
+ // This is an ELF object.
+
+ unconfigured = false;
+ punconfigured = (input_file->will_search_for()
+ ? &unconfigured
+ : NULL);
+ elf_obj = make_elf_object(input_file->filename(),
+ input_file, 0, ehdr, read_size,
+ punconfigured);
+ }
+
if (parameters->options().has_plugins())
{
Pluginobj* obj = parameters->options().plugins()->claim_file(input_file,
- 0, filesize);
+ 0, filesize,
+ elf_obj);
if (obj != NULL)
{
+ // Delete the elf_obj, this file has been claimed.
+ if (elf_obj != NULL)
+ delete elf_obj;
+
// The input file was claimed by a plugin, and its symbols
// have been provided by the plugin.
@@ -359,14 +380,7 @@ Read_symbols::do_read_symbols(Workqueue*
{
// This is an ELF object.
- bool unconfigured = false;
- bool* punconfigured = (input_file->will_search_for()
- ? &unconfigured
- : NULL);
- Object* obj = make_elf_object(input_file->filename(),
- input_file, 0, ehdr, read_size,
- punconfigured);
- if (obj == NULL)
+ if (elf_obj == NULL)
{
if (unconfigured)
{
@@ -382,7 +396,7 @@ Read_symbols::do_read_symbols(Workqueue*
}
Read_symbols_data* sd = new Read_symbols_data;
- obj->read_symbols(sd);
+ elf_obj->read_symbols(sd);
// Opening the file locked it, so now we need to unlock it. We
// need to unlock it before queuing the Add_symbols task,
@@ -397,7 +411,7 @@ Read_symbols::do_read_symbols(Workqueue*
if (this->member_ != NULL)
{
this->member_->sd_ = sd;
- this->member_->obj_ = obj;
+ this->member_->obj_ = elf_obj;
this->member_->arg_serial_ =
this->input_argument_->file().arg_serial();
return true;
@@ -412,7 +426,7 @@ Read_symbols::do_read_symbols(Workqueue*
this->dirindex_,
this->mapfile_,
this->input_argument_,
- obj,
+ elf_obj,
NULL,
sd,
this->this_blocker_,
Index: gold/testsuite/plugin_test.c
===================================================================
RCS file: /cvs/src/src/gold/testsuite/plugin_test.c,v
retrieving revision 1.4
diff -u -u -p -r1.4 plugin_test.c
--- gold/testsuite/plugin_test.c 9 Nov 2009 16:11:34 -0000 1.4
+++ gold/testsuite/plugin_test.c 13 Jul 2011 01:32:38 -0000
@@ -60,6 +60,12 @@ static ld_plugin_add_input_file add_inpu
static ld_plugin_message message = NULL;
static ld_plugin_get_input_file get_input_file = NULL;
static ld_plugin_release_input_file release_input_file = NULL;
+static ld_plugin_get_input_section_count get_input_section_count = NULL;
+static ld_plugin_get_input_section_type get_input_section_type = NULL;
+static ld_plugin_get_input_section_name get_input_section_name = NULL;
+static ld_plugin_get_input_section_contents get_input_section_contents = NULL;
+static ld_plugin_update_section_order update_section_order = NULL;
+static ld_plugin_allow_section_ordering allow_section_ordering = NULL;
#define MAXOPTS 10
@@ -126,6 +132,24 @@ onload(struct ld_plugin_tv *tv)
case LDPT_RELEASE_INPUT_FILE:
release_input_file = entry->tv_u.tv_release_input_file;
break;
+ case LDPT_GET_INPUT_SECTION_COUNT:
+ get_input_section_count = *entry->tv_u.tv_get_input_section_count;
+ break;
+ case LDPT_GET_INPUT_SECTION_TYPE:
+ get_input_section_type = *entry->tv_u.tv_get_input_section_type;
+ break;
+ case LDPT_GET_INPUT_SECTION_NAME:
+ get_input_section_name = *entry->tv_u.tv_get_input_section_name;
+ break;
+ case LDPT_GET_INPUT_SECTION_CONTENTS:
+ get_input_section_contents = *entry->tv_u.tv_get_input_section_contents;
+ break;
+ case LDPT_UPDATE_SECTION_ORDER:
+ update_section_order = *entry->tv_u.tv_update_section_order;
+ break;
+ case LDPT_ALLOW_SECTION_ORDERING:
+ allow_section_ordering = *entry->tv_u.tv_allow_section_ordering;
+ break;
default:
break;
}
@@ -179,6 +203,42 @@ onload(struct ld_plugin_tv *tv)
return LDPS_ERR;
}
+ if (get_input_section_count == NULL)
+ {
+ fprintf(stderr, "tv_get_input_section_count interface missing\n");
+ return LDPS_ERR;
+ }
+
+ if (get_input_section_type == NULL)
+ {
+ fprintf(stderr, "tv_get_input_section_type interface missing\n");
+ return LDPS_ERR;
+ }
+
+ if (get_input_section_name == NULL)
+ {
+ fprintf(stderr, "tv_get_input_section_name interface missing\n");
+ return LDPS_ERR;
+ }
+
+ if (get_input_section_contents == NULL)
+ {
+ fprintf(stderr, "tv_get_input_section_contents interface missing\n");
+ return LDPS_ERR;
+ }
+
+ if (update_section_order == NULL)
+ {
+ fprintf(stderr, "tv_update_section_order interface missing\n");
+ return LDPS_ERR;
+ }
+
+ if (allow_section_ordering == NULL)
+ {
+ fprintf(stderr, "tv_allow_section_ordering interface missing\n");
+ return LDPS_ERR;
+ }
+
return LDPS_OK;
}
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