./:

	* doc/invoke.texi (Debugging Options): Add documentation for the
	-femit-struct-debug options -femit-struct-debug-baseonly,
	-femit-struct-debug-reduced, and
	-femit-struct-debug-detailed[=...].

	* c-opts.c (c_common_handle_option): Add
	OPT_femit_struct_debug_baseonly, OPT_femit_struct_debug_reduced,
	and OPT_femit_struct_debug_detailed_.
	* c.opt: Add specifications for
	-femit-struct-debug-baseonly, -femit-struct-debug-reduced,
	and -femit-struct-debug-detailed[=...].
	* opts.c (set_struct_debug_option): Parse the
	-femit-struct-debug-... options.
	* opts.c (matches_main_base, main_input_basename,
	main_input_baselength, base_of_path, matches_main_base): Add
	variables and functions to compare header base name to compilation
	unit base name.
	* opts.c (should_emit_struct_debug): Add to determine to emit a
	structure based on the option.
	(dump_struct_debug) Also disabled function to debug this
	function.
	* opts.c (handle_options): Save the base name of the
	compilation unit.

	* langhooks-def.h (LANG_HOOKS_GENERIC_TYPE_P): Define.
        (LANG_HOOKS_FOR_TYPES_INITIALIZER): Add.
	This hook indicates if a type is generic.  Set it by default
	to "never generic".
	* langhooks.h (struct lang_hooks_for_types): Add a new hook
	to determine if a struct type is generic or not.
	* cp/cp-tree.h (class_tmpl_impl_spec_p): Declare a C++ hook.
	* cp/tree.c (class_tmpl_impl_spec_p): Implement the C++ hook.
	* cp/cp-lang.c (LANG_HOOKS_GENERIC_TYPE_P): Override null C hook
	with live C++ hook.

	* flags.h (enum debug_info_usage): Add an enumeration to describe
	a program's use of a structure type.
	* dwarf2out.c (gen_struct_or_union_type_die): Add a new parameter
	to indicate the program's usage of the type.  Filter structs based
	on the -femit-struct-debug-... specification.
	(gen_type_die): Split into two routines, gen_type_die and
	gen_type_die_with_usage.  gen_type_die is now a wrapper
	that assumes direct usage.
	(gen_type_die_with_usage): Replace calls to gen_type_die
	with gen_type_die_with_usage adding the program usage of
	the referenced type.
	(dwarf2out_imported_module_or_decl): Suppress struct debug
	information using should_emit_struct_debug when appropriate.
testsuite/:
	* g++.dg/other/fesd-any.C: Test -femit-struct-debug-detailed=any.
	* g++.dg/other/fesd-any.h: Test -femit-struct-debug-detailed=any.
	* g++.dg/other/fesd-baseonly.C: Test -femit-struct-debug-baseonly.
	* g++.dg/other/fesd-baseonly.h: Test -femit-struct-debug-baseonly.
	* g++.dg/other/fesd-none.C: Test -femit-struct-debug-detailed=none.
	* g++.dg/other/fesd-none.h: Test -femit-struct-debug-detailed=none.
	* g++.dg/other/fesd-reduced.C: Test -femit-struct-debug-reduced.
	* g++.dg/other/fesd-reduced.h: Test -femit-struct-debug-reduced.
	* g++.dg/other/fesd-sys.C: Test -femit-struct-debug-detailed=sys.
	* g++.dg/other/fesd-sys.h: Test -femit-struct-debug-detailed=sys.
	* g++.dg/other/fesd.h: Common to -femit-struct-debug-... tests.

	* gcc.dg/fesd-any.c: Test -femit-struct-debug-detailed=any.
	* gcc.dg/fesd-any.h: Test -femit-struct-debug-detailed=any.
	* gcc.dg/fesd-baseonly.c: Test -femit-struct-debug-baseonly.
	* gcc.dg/fesd-baseonly.h: Test -femit-struct-debug-baseonly.
	* gcc.dg/fesd-none.c: Test -femit-struct-debug-detailed=none.
	* gcc.dg/fesd-none.h: Test -femit-struct-debug-detailed=none.
	* gcc.dg/fesd-reduced.c: Test -femit-struct-debug-reduced.
	* gcc.dg/fesd-reduced.h: Test -femit-struct-debug-reduced.
	* gcc.dg/fesd-sys.c: Test -femit-struct-debug-detailed=sys.
	* gcc.dg/fesd-sys.h: Test -femit-struct-debug-detailed=sys.
	* gcc.dg/fesd.h: Common to -femit-struct-debug-... tests.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@123909 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 254 insertions, 0 deletions

diff --git a/gcc/opts.c b/gcc/opts.c
index 195e4e18c3c..0c4a1627e85 100644
--- a/gcc/opts.c
+++ b/gcc/opts.c
@@ -77,6 +77,256 @@ enum debug_info_type write_symbols = NO_DEBUG;
    the definitions of the different possible levels.  */
 enum debug_info_level debug_info_level = DINFO_LEVEL_NONE;
 
+/* A major contribution to object and executable size is debug
+   information size.  A major contribution to debug information size
+   is struct descriptions replicated in several object files. The
+   following flags attempt to reduce this information.  The basic
+   idea is to not emit struct debugging information in the current
+   compilation unit when that information will be generated by
+   another compilation unit.
+
+   Debug information for a struct defined in the current source
+   file should be generated in the object file.  Likewise the
+   debug information for a struct defined in a header should be
+   generated in the object file of the corresponding source file.
+   Both of these case are handled when the base name of the file of
+   the struct definition matches the base name of the source file
+   of thet current compilation unit.  This matching emits minimal
+   struct debugging information.
+
+   The base file name matching rule above will fail to emit debug
+   information for structs defined in system headers.  So a second
+   category of files includes system headers in addition to files
+   with matching bases.
+
+   The remaining types of files are library headers and application
+   headers.  We cannot currently distinguish these two types.  */
+
+enum debug_struct_file
+{
+  DINFO_STRUCT_FILE_NONE,   /* Debug no structs. */
+  DINFO_STRUCT_FILE_BASE,   /* Debug structs defined in files with the
+                               same base name as the compilation unit. */
+  DINFO_STRUCT_FILE_SYS,    /* Also debug structs defined in system
+                               header files.  */
+  DINFO_STRUCT_FILE_ANY     /* Debug structs defined in all files. */
+};
+
+/* Generic structs (e.g. templates not explicitly specialized)
+   may not have a compilation unit associated with them, and so
+   may need to be treated differently from ordinary structs.
+
+   Structs only handled by reference (indirectly), will also usually
+   not need as much debugging information.  */
+
+static enum debug_struct_file debug_struct_ordinary[DINFO_USAGE_NUM_ENUMS]
+  = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY };
+static enum debug_struct_file debug_struct_generic[DINFO_USAGE_NUM_ENUMS]
+  = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY };
+
+/* Parse the -femit-struct-debug-detailed option value
+   and set the flag variables. */
+
+#define MATCH( prefix, string ) \
+  ((strncmp (prefix, string, sizeof prefix - 1) == 0) \
+   ? ((string += sizeof prefix - 1), 1) : 0)
+
+void
+set_struct_debug_option (const char *spec)
+{
+  /* various labels for comparison */
+  static char dfn_lbl[] = "dfn:", dir_lbl[] = "dir:", ind_lbl[] = "ind:";
+  static char ord_lbl[] = "ord:", gen_lbl[] = "gen:";
+  static char none_lbl[] = "none", any_lbl[] = "any";
+  static char base_lbl[] = "base", sys_lbl[] = "sys";
+
+  enum debug_struct_file files = DINFO_STRUCT_FILE_ANY;
+  /* Default is to apply to as much as possible. */
+  enum debug_info_usage usage = DINFO_USAGE_NUM_ENUMS;
+  int ord = 1, gen = 1;
+
+  /* What usage? */
+  if (MATCH (dfn_lbl, spec))
+    usage = DINFO_USAGE_DFN;
+  else if (MATCH (dir_lbl, spec))
+    usage = DINFO_USAGE_DIR_USE;
+  else if (MATCH (ind_lbl, spec))
+    usage = DINFO_USAGE_IND_USE;
+
+  /* Generics or not? */
+  if (MATCH (ord_lbl, spec))
+    gen = 0;
+  else if (MATCH (gen_lbl, spec))
+    ord = 0;
+
+  /* What allowable environment? */
+  if (MATCH (none_lbl, spec))
+    files = DINFO_STRUCT_FILE_NONE;
+  else if (MATCH (any_lbl, spec))
+    files = DINFO_STRUCT_FILE_ANY;
+  else if (MATCH (sys_lbl, spec))
+    files = DINFO_STRUCT_FILE_SYS;
+  else if (MATCH (base_lbl, spec))
+    files = DINFO_STRUCT_FILE_BASE;
+  else
+    error ("argument %qs to %<-femit-struct-debug-detailed%> not recognized",
+           spec);
+
+  /* Effect the specification. */
+  if (usage == DINFO_USAGE_NUM_ENUMS)
+    {
+      if (ord)
+        {
+          debug_struct_ordinary[DINFO_USAGE_DFN] = files;
+          debug_struct_ordinary[DINFO_USAGE_DIR_USE] = files;
+          debug_struct_ordinary[DINFO_USAGE_IND_USE] = files;
+        }
+      if (gen)
+        {
+          debug_struct_generic[DINFO_USAGE_DFN] = files;
+          debug_struct_generic[DINFO_USAGE_DIR_USE] = files;
+          debug_struct_generic[DINFO_USAGE_IND_USE] = files;
+        }
+    }
+  else
+    {
+      if (ord)
+        debug_struct_ordinary[usage] = files;
+      if (gen)
+        debug_struct_generic[usage] = files;
+    }
+
+  if (*spec == ',')
+    set_struct_debug_option (spec+1);
+  else
+    {
+      /* No more -femit-struct-debug-detailed specifications.
+         Do final checks. */
+      if (*spec != '\0')
+	error ("argument %qs to %<-femit-struct-debug-detailed%> unknown",
+               spec);
+      if (debug_struct_ordinary[DINFO_USAGE_DIR_USE]
+		< debug_struct_ordinary[DINFO_USAGE_IND_USE]
+	  || debug_struct_generic[DINFO_USAGE_DIR_USE]
+		< debug_struct_generic[DINFO_USAGE_IND_USE])
+	error ("%<-femit-struct-debug-detailed=dir:...%> must allow at least"
+               " as much as %<-femit-struct-debug-detailed=ind:...%>");
+    }
+}
+
+/* Find the base name of a path, stripping off both directories and
+   a single final extension. */
+static int
+base_of_path (const char *path, const char **base_out)
+{
+  const char *base = path;
+  const char *dot = 0;
+  const char *p = path;
+  char c = *p;
+  while (c)
+    {
+      if (IS_DIR_SEPARATOR(c))
+        {
+          base = p + 1;
+          dot = 0;
+        }
+      else if (c == '.')
+        dot = p;
+      c = *++p;
+    }
+  if (!dot)
+    dot = p;
+  *base_out = base;
+  return dot - base;
+}
+
+/* Match the base name of a file to the base name of a compilation unit. */
+
+static const char *main_input_basename;
+static int main_input_baselength;
+
+static int
+matches_main_base (const char *path)
+{
+  /* Cache the last query. */
+  static const char *last_path = NULL;
+  static int last_match = 0;
+  if (path != last_path)
+    {
+      const char *base;
+      int length = base_of_path (path, &base);
+      last_path = path;
+      last_match = (length == main_input_baselength
+                    && memcmp (base, main_input_basename, length) == 0);
+    }
+  return last_match;
+}
+
+#ifdef DEBUG_DEBUG_STRUCT
+
+static int
+dump_struct_debug (tree type, enum debug_info_usage usage,
+		   enum debug_struct_file criterion, int generic,
+		   int matches, int result)
+{
+  /* Find the type name. */
+  tree type_decl = TYPE_STUB_DECL (type);
+  tree t = type_decl;
+  const char *name = 0;
+  if (TREE_CODE (t) == TYPE_DECL)
+    t = DECL_NAME (t);
+  if (t)
+    name = IDENTIFIER_POINTER (t);
+
+  fprintf (stderr, "	struct %d %s %s %s %s %d %p %s\n",
+	   criterion,
+           DECL_IN_SYSTEM_HEADER (type_decl) ? "sys" : "usr",
+           matches ? "bas" : "hdr",
+           generic ? "gen" : "ord",
+           usage == DINFO_USAGE_DFN ? ";" :
+             usage == DINFO_USAGE_DIR_USE ? "." : "*",
+           result,
+           (void*) type_decl, name);
+  return result;
+}
+#define DUMP_GSTRUCT(type, usage, criterion, generic, matches, result) \
+  dump_struct_debug (type, usage, criterion, generic, matches, result)
+
+#else
+
+#define DUMP_GSTRUCT(type, usage, criterion, generic, matches, result) \
+  (result)
+
+#endif
+
+
+bool
+should_emit_struct_debug (tree type, enum debug_info_usage usage)
+{
+  enum debug_struct_file criterion;
+  tree type_decl;
+  bool generic = lang_hooks.types.generic_p (type);
+
+  if (generic)
+    criterion = debug_struct_generic[usage];
+  else
+    criterion = debug_struct_ordinary[usage];
+
+  if (criterion == DINFO_STRUCT_FILE_NONE)
+    return DUMP_GSTRUCT (type, usage, criterion, generic, false, false);
+  if (criterion == DINFO_STRUCT_FILE_ANY)
+    return DUMP_GSTRUCT (type, usage, criterion, generic, false, true);
+
+  type_decl = TYPE_STUB_DECL (type);
+
+  if (criterion == DINFO_STRUCT_FILE_SYS && DECL_IN_SYSTEM_HEADER (type_decl))
+    return DUMP_GSTRUCT (type, usage, criterion, generic, false, true);
+
+  if (matches_main_base (DECL_SOURCE_FILE (type_decl)))
+    return DUMP_GSTRUCT (type, usage, criterion, generic, true, true);
+  return DUMP_GSTRUCT (type, usage, criterion, generic, false, false);
+}
+
 /* Nonzero means use GNU-only extensions in the generated symbolic
    debugging information.  Currently, this only has an effect when
    write_symbols is set to DBX_DEBUG, XCOFF_DEBUG, or DWARF_DEBUG.  */
@@ -368,7 +618,11 @@ handle_options (unsigned int argc, const char **argv, unsigned int lang_mask)
       if (opt[0] != '-' || opt[1] == '\0')
 	{
 	  if (main_input_filename == NULL)
+	    {
 	    main_input_filename = opt;
+	      main_input_baselength
+		= base_of_path (main_input_filename, &main_input_basename);
+	    }
 	  add_input_filename (opt);
 	  n = 1;
 	  continue;