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.

1 files changed, 65 insertions, 1 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.