[PATCH] Nuke gen_tagged_type_instantiation_die (PR debug/39412)

[Jakub Jelinek <jakub at redhat dot com>]

Hi!

As shown on the attached testcase, gen_tagged_type_instantiation_die
doesn't handle qualified types.  While it could be taught to do that,
currently nothing ever can reference those DIEs (that DIE isn't equated to
type uid, so normally is pruned as unused anyway, and for all vars with
that type a DIE should be already emitted in the abstract origin subroutine
DIE), so this patch instead removes that function and does nothing for
TYPE_DECL_IS_STUB with decl_origin () != NULL.

Bootstrapped/regtested on x86_64-linux, ok for trunk?

2009-03-11  Jakub Jelinek  <jakub@redhat.com>

	PR debug/39412
	* dwarf2out.c (gen_inlined_enumeration_type_die,
	gen_inlined_structure_type_die, gen_inlined_union_type_die,
	gen_tagged_type_instantiation_die): Removed.
	(gen_decl_die): For TYPE_DECL_IS_STUB with non-NULL decl_origin
	do nothing.

	* gcc.dg/debug/pr39412.c: New test.

--- gcc/dwarf2out.c.jj	2009-03-09 11:38:55.000000000 +0100
+++ gcc/dwarf2out.c	2009-03-11 11:12:02.000000000 +0100
@@ -5149,9 +5149,6 @@ static void gen_descr_array_type_die (tr
 #if 0
 static void gen_entry_point_die (tree, dw_die_ref);
 #endif
-static void gen_inlined_enumeration_type_die (tree, dw_die_ref);
-static void gen_inlined_structure_type_die (tree, dw_die_ref);
-static void gen_inlined_union_type_die (tree, dw_die_ref);
 static dw_die_ref gen_enumeration_type_die (tree, dw_die_ref);
 static dw_die_ref gen_formal_parameter_die (tree, tree, dw_die_ref);
 static void gen_unspecified_parameters_die (tree, dw_die_ref);
@@ -5172,7 +5169,6 @@ static void gen_struct_or_union_type_die
 static void gen_subroutine_type_die (tree, dw_die_ref);
 static void gen_typedef_die (tree, dw_die_ref);
 static void gen_type_die (tree, dw_die_ref);
-static void gen_tagged_type_instantiation_die (tree, dw_die_ref);
 static void gen_block_die (tree, dw_die_ref, int);
 static void decls_for_scope (tree, dw_die_ref, int);
 static int is_redundant_typedef (const_tree);
@@ -13149,18 +13145,6 @@ retry_incomplete_types (void)
     gen_type_die (VEC_index (tree, incomplete_types, i), comp_unit_die);
 }
 
-/* Generate a DIE to represent an inlined instance of an enumeration type.  */
-
-static void
-gen_inlined_enumeration_type_die (tree type, dw_die_ref context_die)
-{
-  dw_die_ref type_die = new_die (DW_TAG_enumeration_type, context_die, type);
-
-  /* We do not check for TREE_ASM_WRITTEN (type) being set, as the type may
-     be incomplete and such types are not marked.  */
-  add_abstract_origin_attribute (type_die, type);
-}
-
 /* Determine what tag to use for a record type.  */
 
 static enum dwarf_tag
@@ -13185,30 +13169,6 @@ record_type_tag (tree type)
     }
 }
 
-/* Generate a DIE to represent an inlined instance of a structure type.  */
-
-static void
-gen_inlined_structure_type_die (tree type, dw_die_ref context_die)
-{
-  dw_die_ref type_die = new_die (record_type_tag (type), context_die, type);
-
-  /* We do not check for TREE_ASM_WRITTEN (type) being set, as the type may
-     be incomplete and such types are not marked.  */
-  add_abstract_origin_attribute (type_die, type);
-}
-
-/* Generate a DIE to represent an inlined instance of a union type.  */
-
-static void
-gen_inlined_union_type_die (tree type, dw_die_ref context_die)
-{
-  dw_die_ref type_die = new_die (DW_TAG_union_type, context_die, type);
-
-  /* We do not check for TREE_ASM_WRITTEN (type) being set, as the type may
-     be incomplete and such types are not marked.  */
-  add_abstract_origin_attribute (type_die, type);
-}
-
 /* Generate a DIE to represent an enumeration type.  Note that these DIEs
    include all of the information about the enumeration values also. Each
    enumerated type name/value is listed as a child of the enumerated type
@@ -14835,46 +14795,6 @@ gen_type_die (tree type, dw_die_ref cont
   gen_type_die_with_usage (type, context_die, DINFO_USAGE_DIR_USE);
 }
 
-/* Generate a DIE for a tagged type instantiation.  */
-
-static void
-gen_tagged_type_instantiation_die (tree type, dw_die_ref context_die)
-{
-  if (type == NULL_TREE || type == error_mark_node)
-    return;
-
-  /* We are going to output a DIE to represent the unqualified version of
-     this type (i.e. without any const or volatile qualifiers) so make sure
-     that we have the main variant (i.e. the unqualified version) of this
-     type now.  */
-  gcc_assert (type == type_main_variant (type));
-
-  /* Do not check TREE_ASM_WRITTEN (type) as it may not be set if this is
-     an instance of an unresolved type.  */
-
-  switch (TREE_CODE (type))
-    {
-    case ERROR_MARK:
-      break;
-
-    case ENUMERAL_TYPE:
-      gen_inlined_enumeration_type_die (type, context_die);
-      break;
-
-    case RECORD_TYPE:
-      gen_inlined_structure_type_die (type, context_die);
-      break;
-
-    case UNION_TYPE:
-    case QUAL_UNION_TYPE:
-      gen_inlined_union_type_die (type, context_die);
-      break;
-
-    default:
-      gcc_unreachable ();
-    }
-}
-
 /* Generate a DW_TAG_lexical_block DIE followed by DIEs to represent all of the
    things which are local to the given block.  */
 
@@ -15315,14 +15235,14 @@ gen_decl_die (tree decl, tree origin, dw
 	 of some type tag, if the given TYPE_DECL is marked as having been
 	 instantiated from some other (original) TYPE_DECL node (e.g. one which
 	 was generated within the original definition of an inline function) we
-	 have to generate a special (abbreviated) DW_TAG_structure_type,
-	 DW_TAG_union_type, or DW_TAG_enumeration_type DIE here.  */
-      if (TYPE_DECL_IS_STUB (decl) && decl_ultimate_origin (decl) != NULL_TREE
-	  && is_tagged_type (TREE_TYPE (decl)))
-	{
-	  gen_tagged_type_instantiation_die (TREE_TYPE (decl), context_die);
-	  break;
-	}
+	 used to generate a special (abbreviated) DW_TAG_structure_type,
+	 DW_TAG_union_type, or DW_TAG_enumeration_type DIE here.  But nothing
+	 should be actually referencing those DIEs, as variable DIEs with that
+	 type would be emitted already in the abstract origin, so it was always
+	 removed during unused type prunning.  Don't add anything in this
+	 case.  */
+      if (TYPE_DECL_IS_STUB (decl) && decl_ultimate_origin (decl) != NULL_TREE)
+	break;
 
       if (is_redundant_typedef (decl))
 	gen_type_die (TREE_TYPE (decl), context_die);
--- gcc/testsuite/gcc.dg/debug/pr39412.c.jj	2009-03-11 11:14:32.000000000 +0100
+++ gcc/testsuite/gcc.dg/debug/pr39412.c	2009-03-11 11:14:39.000000000 +0100
@@ -0,0 +1,16 @@
+/* PR debug/39412 */
+/* { dg-do compile } */
+
+struct S { int i; };
+
+inline void
+bar (const void *x, unsigned long y)
+{
+  const union { struct S a[y]; } *u = x;
+}
+
+void
+foo (const void *x, unsigned long y)
+{
+  bar (x, y);
+}

	Jakub