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[binutils-gdb] Add new plugin hooks to support querying section alignment and size.
- From: Cary Coutant <ccoutant at sourceware dot org>
- To: bfd-cvs at sourceware dot org
- Date: 3 Mar 2016 20:10:32 -0000
- Subject: [binutils-gdb] Add new plugin hooks to support querying section alignment and size.
https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=82838bd626b10f1a82b0de29728c26f4458ec514
commit 82838bd626b10f1a82b0de29728c26f4458ec514
Author: Cary Coutant <ccoutant@gmail.com>
Date: Thu Mar 3 12:09:06 2016 -0800
Add new plugin hooks to support querying section alignment and size.
include/
2016-03-03 Than McIntosh <thanm@google.com>
* plugin-api.h: Add new hooks to the plugin transfer vector to
to support querying section alignment and section size.
(ld_plugin_get_input_section_alignment): New hook.
(ld_plugin_get_input_section_size): New hook.
(ld_plugin_tag): Add LDPT_GET_INPUT_SECTION_ALIGNMENT
and LDPT_GET_INPUT_SECTION_SIZE.
(ld_plugin_tv): Add tv_get_input_section_alignment and
tv_get_input_section_size.
gold/
2016-03-03 Than McIntosh <thanm@google.com>
* plugin.cc (Plugin::load): Include hooks for get_input_section_size
and get_input_section_alignment in transfer vector.
(get_input_section_alignment): New function.
(get_input_section_size): New function.
* testsuite/Makefile.am: Add plugin_layout_with_alignment.sh test.
* testsuite/Makefile.in: [Regenerate.]
* testsuite/plugin_section_alignment.cc: New test file.
* testsuite/plugin_layout_with_alignment.cc: New test file.
* testsuite/plugin_layout_with_alignment.sh: New test file.
Diff:
---
gold/plugin.cc | 66 +++++-
gold/testsuite/Makefile.am | 15 ++
gold/testsuite/Makefile.in | 23 ++-
gold/testsuite/plugin_layout_with_alignment.cc | 72 +++++++
gold/testsuite/plugin_layout_with_alignment.sh | 66 ++++++
gold/testsuite/plugin_section_alignment.cc | 267 +++++++++++++++++++++++++
include/plugin-api.h | 26 ++-
7 files changed, 530 insertions(+), 5 deletions(-)
diff --git a/gold/plugin.cc b/gold/plugin.cc
index 4aeb3ea..bb7d6b2 100644
--- a/gold/plugin.cc
+++ b/gold/plugin.cc
@@ -158,6 +158,15 @@ unique_segment_for_sections(const char* segment_name,
uint64_t align,
const struct ld_plugin_section *section_list,
unsigned int num_sections);
+
+static enum ld_plugin_status
+get_input_section_alignment(const struct ld_plugin_section section,
+ unsigned int* addralign);
+
+static enum ld_plugin_status
+get_input_section_size(const struct ld_plugin_section section,
+ uint64_t* secsize);
+
};
#endif // ENABLE_PLUGINS
@@ -202,7 +211,7 @@ Plugin::load()
sscanf(ver, "%d.%d", &major, &minor);
// Allocate and populate a transfer vector.
- const int tv_fixed_size = 27;
+ const int tv_fixed_size = 29;
int tv_size = this->args_.size() + tv_fixed_size;
ld_plugin_tv* tv = new ld_plugin_tv[tv_size];
@@ -329,6 +338,14 @@ Plugin::load()
tv[i].tv_u.tv_unique_segment_for_sections = unique_segment_for_sections;
++i;
+ tv[i].tv_tag = LDPT_GET_INPUT_SECTION_ALIGNMENT;
+ tv[i].tv_u.tv_get_input_section_alignment = get_input_section_alignment;
+
+ ++i;
+ tv[i].tv_tag = LDPT_GET_INPUT_SECTION_SIZE;
+ tv[i].tv_u.tv_get_input_section_size = get_input_section_size;
+
+ ++i;
tv[i].tv_tag = LDPT_NULL;
tv[i].tv_u.tv_val = 0;
@@ -1730,6 +1747,53 @@ get_input_section_contents(const struct ld_plugin_section section,
return LDPS_OK;
}
+// Get the alignment 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_alignment(const struct ld_plugin_section section,
+ unsigned int* addralign)
+{
+ 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;
+
+ *addralign = obj->section_addralign(section.shndx);
+ return LDPS_OK;
+}
+
+// Get the size 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_size(const struct ld_plugin_section section,
+ uint64_t* secsize)
+{
+ 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;
+
+ *secsize = obj->section_size(section.shndx);
+ 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.
diff --git a/gold/testsuite/Makefile.am b/gold/testsuite/Makefile.am
index d78ec6c..f8bf1e6 100644
--- a/gold/testsuite/Makefile.am
+++ b/gold/testsuite/Makefile.am
@@ -2101,6 +2101,21 @@ plugin_section_order.so: plugin_section_order.o
plugin_section_order.o: plugin_section_order.c
$(COMPILE) -O0 -c -fpic -o $@ $<
+check_SCRIPTS += plugin_layout_with_alignment.sh
+check_DATA += plugin_layout_with_alignment.stdout
+MOSTLYCLEANFILES += plugin_layout_with_alignment
+plugin_layout_with_alignment.o: plugin_layout_with_alignment.cc
+ $(CXXCOMPILE) -O0 -c -ffunction-sections -fdata-sections -g -o $@ $<
+plugin_layout_with_alignment: plugin_layout_with_alignment.o plugin_section_alignment.so gcctestdir/ld
+ $(CXXLINK) -Bgcctestdir/ -Wl,--plugin,"./plugin_section_alignment.so" plugin_layout_with_alignment.o
+plugin_layout_with_alignment.stdout: plugin_layout_with_alignment
+ $(TEST_NM) -n --synthetic plugin_layout_with_alignment > plugin_layout_with_alignment.stdout
+
+plugin_section_alignment.so: plugin_section_alignment.o
+ $(CXXLINK) -Bgcctestdir/ -shared plugin_section_alignment.o
+plugin_section_alignment.o: plugin_section_alignment.cc
+ $(CXXCOMPILE) -O0 -c -fpic -o $@ $<
+
endif PLUGINS
check_PROGRAMS += exclude_libs_test
diff --git a/gold/testsuite/Makefile.in b/gold/testsuite/Makefile.in
index 874d0bf..48cd631 100644
--- a/gold/testsuite/Makefile.in
+++ b/gold/testsuite/Makefile.in
@@ -474,9 +474,13 @@ check_PROGRAMS = $(am__EXEEXT_1) $(am__EXEEXT_2) $(am__EXEEXT_3) \
@GCC_TRUE@@NATIVE_LINKER_TRUE@@PLUGINS_TRUE@@TLS_TRUE@am__append_43 = plugin_test_tls.err
@GCC_TRUE@@NATIVE_LINKER_TRUE@@PLUGINS_TRUE@@TLS_TRUE@am__append_44 = plugin_test_tls.err
@GCC_TRUE@@NATIVE_LINKER_TRUE@@PLUGINS_TRUE@am__append_45 = unused.c \
-@GCC_TRUE@@NATIVE_LINKER_TRUE@@PLUGINS_TRUE@ plugin_final_layout
-@GCC_TRUE@@NATIVE_LINKER_TRUE@@PLUGINS_TRUE@am__append_46 = plugin_final_layout.sh
-@GCC_TRUE@@NATIVE_LINKER_TRUE@@PLUGINS_TRUE@am__append_47 = plugin_final_layout.stdout plugin_final_layout_readelf.stdout
+@GCC_TRUE@@NATIVE_LINKER_TRUE@@PLUGINS_TRUE@ plugin_final_layout \
+@GCC_TRUE@@NATIVE_LINKER_TRUE@@PLUGINS_TRUE@ plugin_layout_with_alignment
+@GCC_TRUE@@NATIVE_LINKER_TRUE@@PLUGINS_TRUE@am__append_46 = plugin_final_layout.sh \
+@GCC_TRUE@@NATIVE_LINKER_TRUE@@PLUGINS_TRUE@ plugin_layout_with_alignment.sh
+@GCC_TRUE@@NATIVE_LINKER_TRUE@@PLUGINS_TRUE@am__append_47 = plugin_final_layout.stdout \
+@GCC_TRUE@@NATIVE_LINKER_TRUE@@PLUGINS_TRUE@ plugin_final_layout_readelf.stdout \
+@GCC_TRUE@@NATIVE_LINKER_TRUE@@PLUGINS_TRUE@ plugin_layout_with_alignment.stdout
@GCC_TRUE@@NATIVE_LINKER_TRUE@am__append_48 = exclude_libs_test \
@GCC_TRUE@@NATIVE_LINKER_TRUE@ local_labels_test \
@GCC_TRUE@@NATIVE_LINKER_TRUE@ discard_locals_test
@@ -4561,6 +4565,8 @@ plugin_test_tls.sh.log: plugin_test_tls.sh
@p='plugin_test_tls.sh'; $(am__check_pre) $(LOG_COMPILE) "$$tst" $(am__check_post)
plugin_final_layout.sh.log: plugin_final_layout.sh
@p='plugin_final_layout.sh'; $(am__check_pre) $(LOG_COMPILE) "$$tst" $(am__check_post)
+plugin_layout_with_alignment.sh.log: plugin_layout_with_alignment.sh
+ @p='plugin_layout_with_alignment.sh'; $(am__check_pre) $(LOG_COMPILE) "$$tst" $(am__check_post)
exclude_libs_test.sh.log: exclude_libs_test.sh
@p='exclude_libs_test.sh'; $(am__check_pre) $(LOG_COMPILE) "$$tst" $(am__check_post)
discard_locals_test.sh.log: discard_locals_test.sh
@@ -6131,6 +6137,17 @@ uninstall-am:
@GCC_TRUE@@NATIVE_LINKER_TRUE@@PLUGINS_TRUE@ $(LINK) -Bgcctestdir/ -shared plugin_section_order.o
@GCC_TRUE@@NATIVE_LINKER_TRUE@@PLUGINS_TRUE@plugin_section_order.o: plugin_section_order.c
@GCC_TRUE@@NATIVE_LINKER_TRUE@@PLUGINS_TRUE@ $(COMPILE) -O0 -c -fpic -o $@ $<
+@GCC_TRUE@@NATIVE_LINKER_TRUE@@PLUGINS_TRUE@plugin_layout_with_alignment.o: plugin_layout_with_alignment.cc
+@GCC_TRUE@@NATIVE_LINKER_TRUE@@PLUGINS_TRUE@ $(CXXCOMPILE) -O0 -c -ffunction-sections -fdata-sections -g -o $@ $<
+@GCC_TRUE@@NATIVE_LINKER_TRUE@@PLUGINS_TRUE@plugin_layout_with_alignment: plugin_layout_with_alignment.o plugin_section_alignment.so gcctestdir/ld
+@GCC_TRUE@@NATIVE_LINKER_TRUE@@PLUGINS_TRUE@ $(CXXLINK) -Bgcctestdir/ -Wl,--plugin,"./plugin_section_alignment.so" plugin_layout_with_alignment.o
+@GCC_TRUE@@NATIVE_LINKER_TRUE@@PLUGINS_TRUE@plugin_layout_with_alignment.stdout: plugin_layout_with_alignment
+@GCC_TRUE@@NATIVE_LINKER_TRUE@@PLUGINS_TRUE@ $(TEST_NM) -n --synthetic plugin_layout_with_alignment > plugin_layout_with_alignment.stdout
+
+@GCC_TRUE@@NATIVE_LINKER_TRUE@@PLUGINS_TRUE@plugin_section_alignment.so: plugin_section_alignment.o
+@GCC_TRUE@@NATIVE_LINKER_TRUE@@PLUGINS_TRUE@ $(CXXLINK) -Bgcctestdir/ -shared plugin_section_alignment.o
+@GCC_TRUE@@NATIVE_LINKER_TRUE@@PLUGINS_TRUE@plugin_section_alignment.o: plugin_section_alignment.cc
+@GCC_TRUE@@NATIVE_LINKER_TRUE@@PLUGINS_TRUE@ $(CXXCOMPILE) -O0 -c -fpic -o $@ $<
@GCC_TRUE@@NATIVE_LINKER_TRUE@exclude_libs_test.syms: exclude_libs_test
@GCC_TRUE@@NATIVE_LINKER_TRUE@ $(TEST_READELF) -sW $< >$@ 2>/dev/null
@GCC_TRUE@@NATIVE_LINKER_TRUE@libexclude_libs_test_1.a: exclude_libs_test_1.o
diff --git a/gold/testsuite/plugin_layout_with_alignment.cc b/gold/testsuite/plugin_layout_with_alignment.cc
new file mode 100644
index 0000000..0824d74
--- /dev/null
+++ b/gold/testsuite/plugin_layout_with_alignment.cc
@@ -0,0 +1,72 @@
+// plugin_layout_with_alignment.cc -- a test case for gold
+
+// Copyright (C) 2016 Free Software Foundation, Inc.
+// Written by Than McIntosh <thanm@google.com>.
+
+// This file is part of gold.
+
+// This program is free software; you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation; either version 3 of the License, or
+// (at your option) any later version.
+
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
+// MA 02110-1301, USA.
+
+// Verify that plugin interfaces for section size and alignment work
+// correctly, and that section ordering via plugins is working
+// for .bss/.rodata/.data sections.
+
+// --- Initialized .rodata items
+
+__attribute__ ((section(".rodata.v1_a2")))
+const short rodata_item1 = 101;
+
+__attribute__ ((section(".rodata.v2_a1")))
+const char rodata_item2 = 'a';
+
+__attribute__ ((section(".rodata.v3_a8")))
+const double rodata_item3 = 777.777;
+
+__attribute__ ((section(".rodata.v4_a1")))
+const char rodata_item4[7] = {'1', '2', '3', '4', '5', '6', '7'};
+
+// --- Initialized .data items
+
+__attribute__ ((section(".data.v1_a2")))
+short rwdata_item1 = 101;
+
+__attribute__ ((section(".data.v2_a1")))
+char rwdata_item2 = 'a';
+
+__attribute__ ((section(".data.v3_a8")))
+double rwdata_item3 = 'b';
+
+__attribute__ ((section(".data.v4_a1")))
+char rwdata_item4[3] = {'a', 'b', 'c'};
+
+// --- Uninitialized .data items
+
+__attribute__ ((section(".bss.v1_a2")))
+short bss_item1;
+
+__attribute__ ((section(".bss.v2_a1")))
+char bss_item2;
+
+__attribute__ ((section(".bss.v3_a8")))
+struct blah { union { double d; char c; } u; } bss_item3;
+
+__attribute__ ((section(".bss.v4_a1")))
+char bss_item4[3];
+
+int main ()
+{
+ return 0;
+}
diff --git a/gold/testsuite/plugin_layout_with_alignment.sh b/gold/testsuite/plugin_layout_with_alignment.sh
new file mode 100644
index 0000000..c5f07ae
--- /dev/null
+++ b/gold/testsuite/plugin_layout_with_alignment.sh
@@ -0,0 +1,66 @@
+#!/bin/sh
+
+# plugin_layout_with_alignment.sh -- test
+
+# Copyright (C) 2016 Free Software Foundation, Inc.
+# Written by Than McIntosh <thanm@google.com>.
+
+# This file is part of gold.
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
+# MA 02110-1301, USA.
+
+# The goal of this program is to verify plugin alignment and size
+# interfaces and working correctly in combination with section ordering.
+# intended. File plugin_layout_with_alignment.cc is in this test.
+
+
+set -e
+
+check()
+{
+ awk "
+BEGIN { saw1 = 0; saw2 = 0; saw3 = 0; saw4 = 0; counter = 1; err = 0; ord = \"\"; }
+/.*$2\$/ { saw1 = counter; counter = counter + 1; ord = ord \" $2\"; }
+/.*$3\$/ { saw2 = counter; counter = counter + 1; ord = ord \" $3\"; }
+/.*$4\$/ { saw3 = counter; counter = counter + 1; ord = ord \" $4\"; }
+/.*$5\$/ { saw4 = counter; counter = counter + 1; ord = ord \" $5\"; }
+END {
+ if (!saw1) {
+ printf \"did not see $2\\n\";
+ exit 1;
+ }
+ if (!saw2) {
+ printf \"did not see $3\\n\";
+ exit 1;
+ }
+ if (!saw3) {
+ printf \"did not see $4\\n\";
+ exit 1;
+ }
+ if (!saw4) {
+ printf \"did not see $5\\n\";
+ exit 1;
+ }
+ if (saw1 != 1 || saw2 != 2 || saw3 != 3 || saw4 != 4) {
+ printf \"incorrect ordering:\\nwas:%s\\nshould have been: $2 $3 $4 $5\\n\", ord;
+ exit 1;
+ }
+ }" $1
+}
+
+check plugin_layout_with_alignment.stdout "bss_item3" "bss_item1" "bss_item4" "bss_item2"
+check plugin_layout_with_alignment.stdout "rwdata_item2" "rwdata_item4" "rwdata_item1" "rwdata_item3"
+check plugin_layout_with_alignment.stdout "rodata_item3" "rodata_item1" "rodata_item2" "rodata_item4"
diff --git a/gold/testsuite/plugin_section_alignment.cc b/gold/testsuite/plugin_section_alignment.cc
new file mode 100644
index 0000000..6f64bdc
--- /dev/null
+++ b/gold/testsuite/plugin_section_alignment.cc
@@ -0,0 +1,267 @@
+// plugin_section_alignment.cc -- plugins to test ordering with {size,alignment}
+//
+// Copyright (C) 2016 Free Software Foundation, Inc.
+// Written by Than McIntosh <thanm@google.com>.
+//
+// This file is part of gold.
+//
+// This program is free software; you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation; either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
+// MA 02110-1301, USA.
+//
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <string>
+#include <vector>
+#include <algorithm>
+
+#include "plugin-api.h"
+
+static ld_plugin_get_input_section_count get_input_section_count = NULL;
+static ld_plugin_get_input_section_alignment get_input_section_alignment = NULL;
+static ld_plugin_get_input_section_size get_input_section_size = NULL;
+static ld_plugin_get_input_section_name get_input_section_name = NULL;
+static ld_plugin_update_section_order update_section_order = NULL;
+static ld_plugin_allow_section_ordering allow_section_ordering = NULL;
+
+extern "C" {
+ enum ld_plugin_status onload(struct ld_plugin_tv *tv);
+ enum ld_plugin_status claim_file_hook(const struct ld_plugin_input_file *file,
+ int *claimed);
+ enum ld_plugin_status all_symbols_read_hook(void);
+}
+
+typedef enum { FL_BSS, FL_DATA, FL_RODATA, FL_UNKNOWN } sec_flavor;
+
+inline static int is_prefix_of(const char *prefix, const char *str)
+{
+ return strncmp(prefix, str, strlen(prefix)) == 0;
+}
+
+inline static sec_flavor flavor_from_name(const char *secname)
+{
+ if (is_prefix_of(".data.v", secname)) {
+ return FL_DATA;
+ } else if (is_prefix_of(".bss.v", secname)) {
+ return FL_BSS;
+ } else if (is_prefix_of(".rodata.v", secname)) {
+ return FL_RODATA;
+ } else {
+ return FL_UNKNOWN;
+ }
+}
+
+struct SectionInfo {
+ ld_plugin_section plugin_section;
+ std::string name;
+ uint64_t size;
+ sec_flavor flavor;
+ unsigned align;
+
+ static bool SectionInfoLt(const SectionInfo &i1,
+ const SectionInfo &i2)
+ {
+ if (i1.flavor != i2.flavor) {
+ return ((unsigned) i1.flavor) < ((unsigned) i2.flavor);
+ }
+ switch (i1.flavor) {
+ case FL_DATA:
+ // Sort data items by increasing alignment then increasing size
+ if (i1.align != i2.align) {
+ return ((unsigned) i1.align) < ((unsigned) i2.align);
+ }
+ if (i1.size != i2.size) {
+ return ((unsigned) i1.size) < ((unsigned) i2.size);
+ }
+ break;
+ case FL_BSS:
+ // Sort bss items by decreasing alignment then decreasing size
+ if (i1.align != i2.align) {
+ return ((unsigned) i2.align) < ((unsigned) i1.align);
+ }
+ if (i1.size != i2.size) {
+ return ((unsigned) i2.size) < ((unsigned) i1.size);
+ }
+ break;
+ case FL_RODATA:
+ // Sort rodata items by decreasing alignment then increasing size
+ if (i1.align != i2.align) {
+ return ((unsigned) i2.align) < ((unsigned) i1.align);
+ }
+ if (i1.size != i2.size) {
+ return ((unsigned) i1.size) < ((unsigned) i2.size);
+ }
+ default:
+ break;
+ }
+
+ // Break ties by name
+ return i1.name.compare(i2.name) < 0;
+ }
+
+};
+typedef std::vector<SectionInfo> section_info_vector;
+section_info_vector raw_sections;
+
+// Set to 1 for debugging output
+unsigned trace = 0;
+
+extern "C" {
+
+// Plugin entry point.
+enum ld_plugin_status onload(struct ld_plugin_tv *tv)
+{
+ struct ld_plugin_tv *entry;
+ for (entry = tv; entry->tv_tag != LDPT_NULL; ++entry)
+ {
+ switch (entry->tv_tag)
+ {
+ case LDPT_OPTION:
+ if (!strcmp(entry->tv_u.tv_string,"-trace")) {
+ fprintf(stderr, "enabling tracing\n");
+ trace += 1;
+ } else {
+ fprintf(stderr, "unknown plugin option %s", entry->tv_u.tv_string);
+ }
+ break;
+ case LDPT_REGISTER_CLAIM_FILE_HOOK:
+ assert((*entry->tv_u.tv_register_claim_file)(claim_file_hook) ==
+ LDPS_OK);
+ break;
+ case LDPT_REGISTER_ALL_SYMBOLS_READ_HOOK:
+ assert((*entry->tv_u.tv_register_all_symbols_read)(
+ all_symbols_read_hook) == LDPS_OK);
+ 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_NAME:
+ get_input_section_name = *entry->tv_u.tv_get_input_section_name;
+ break;
+ case LDPT_GET_INPUT_SECTION_ALIGNMENT:
+ get_input_section_alignment =
+ *entry->tv_u.tv_get_input_section_alignment;
+ break;
+ case LDPT_GET_INPUT_SECTION_SIZE:
+ get_input_section_size = *entry->tv_u.tv_get_input_section_size;
+ 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;
+ }
+ }
+
+ if (get_input_section_count == NULL || get_input_section_alignment == NULL ||
+ get_input_section_size == NULL || get_input_section_name == NULL ||
+ update_section_order == NULL || allow_section_ordering == NULL) {
+ fprintf(stderr, "Some interfaces are missing\n");
+ return LDPS_ERR;
+ }
+
+ return LDPS_OK;
+}
+
+// This function is called by the linker for every new object it encounters.
+enum ld_plugin_status claim_file_hook(const struct ld_plugin_input_file *file,
+ int *claimed)
+{
+ static bool is_ordering_specified = false;
+ struct ld_plugin_section section;
+ unsigned count = 0;
+ unsigned shndx;
+
+ *claimed = 0;
+ if (!is_ordering_specified) {
+ // Inform the linker to prepare for section reordering.
+ (*allow_section_ordering)();
+ is_ordering_specified = true;
+ }
+
+ (*get_input_section_count)(file->handle, &count);
+
+ for (shndx = 0; shndx < count; ++shndx) {
+ char *name = NULL;
+
+ section.handle = file->handle;
+ section.shndx = shndx;
+ (*get_input_section_name)(section, &name);
+ if (is_prefix_of(".data.v", name) ||
+ is_prefix_of(".bss.v", name) ||
+ is_prefix_of(".rodata.v", name)) {
+ SectionInfo si;
+ si.plugin_section.handle = file->handle;
+ si.plugin_section.shndx = shndx;
+ (*get_input_section_size)(section, &si.size);
+ (*get_input_section_alignment)(section, &si.align);
+ si.name = name;
+ si.flavor = flavor_from_name(name);
+ raw_sections.push_back(si);
+ }
+ }
+
+ return LDPS_OK;
+}
+
+// This function is called by the linker after all the symbols have been read.
+// At this stage, it is fine to tell the linker the desired function order.
+
+enum ld_plugin_status all_symbols_read_hook(void)
+{
+ // We expect to see a total of twelve sections -- if this is not the case
+ // then something went wrong somewhere along the way.
+ if (raw_sections.size() != 12) {
+ fprintf(stderr, "Expected 12 sections, found %u sections",
+ (unsigned) raw_sections.size());
+ return LDPS_ERR;
+ }
+
+ std::sort(raw_sections.begin(), raw_sections.end(),
+ SectionInfo::SectionInfoLt);
+
+ struct ld_plugin_section section_list[12];
+ for (unsigned ii = 0; ii < 12; ++ii) {
+ section_list[ii] = raw_sections[ii].plugin_section;
+ }
+
+ if (trace) {
+ fprintf(stderr, "Specified section order is:\n");
+ for (section_info_vector::iterator it = raw_sections.begin();
+ it != raw_sections.end();
+ ++it) {
+ const SectionInfo &si = (*it);
+ fprintf(stderr, "Idx=%u Name=%s Align=%u Size=%u\n",
+ si.plugin_section.shndx, si.name.c_str(), si.align,
+ (unsigned) si.size);
+ }
+ }
+
+ update_section_order(section_list, 12);
+
+ return LDPS_OK;
+}
+
+} // end extern "C"
diff --git a/include/plugin-api.h b/include/plugin-api.h
index 811e6e4..a794a37 100644
--- a/include/plugin-api.h
+++ b/include/plugin-api.h
@@ -345,6 +345,26 @@ enum ld_plugin_status
const struct ld_plugin_section * section_list,
unsigned int num_sections);
+/* The linker's interface for retrieving the section alignment requirement
+ of a specific section in an object. This interface should only be invoked in the
+ claim_file handler. This function sets *ADDRALIGN to the ELF sh_addralign
+ value of the input section. */
+
+typedef
+enum ld_plugin_status
+(*ld_plugin_get_input_section_alignment) (const struct ld_plugin_section section,
+ unsigned int *addralign);
+
+/* The linker's interface for retrieving the section size of a specific section
+ in an object. This interface should only be invoked in the claim_file handler.
+ This function sets *SECSIZE to the ELF sh_size
+ value of the input section. */
+
+typedef
+enum ld_plugin_status
+(*ld_plugin_get_input_section_size) (const struct ld_plugin_section section,
+ uint64_t *secsize);
+
enum ld_plugin_level
{
LDPL_INFO,
@@ -385,7 +405,9 @@ enum ld_plugin_tag
LDPT_GET_SYMBOLS_V2 = 25,
LDPT_ALLOW_UNIQUE_SEGMENT_FOR_SECTIONS = 26,
LDPT_UNIQUE_SEGMENT_FOR_SECTIONS = 27,
- LDPT_GET_SYMBOLS_V3 = 28
+ LDPT_GET_SYMBOLS_V3 = 28,
+ LDPT_GET_INPUT_SECTION_ALIGNMENT = 29,
+ LDPT_GET_INPUT_SECTION_SIZE = 30
};
/* The plugin transfer vector. */
@@ -417,6 +439,8 @@ struct ld_plugin_tv
ld_plugin_allow_section_ordering tv_allow_section_ordering;
ld_plugin_allow_unique_segment_for_sections tv_allow_unique_segment_for_sections;
ld_plugin_unique_segment_for_sections tv_unique_segment_for_sections;
+ ld_plugin_get_input_section_alignment tv_get_input_section_alignment;
+ ld_plugin_get_input_section_size tv_get_input_section_size;
} tv_u;
};