gigi.h, trans.c (Identifier_to_gnu): Change test for deferred constant by adding…

gigi.h, trans.c (Identifier_to_gnu): Change test for deferred constant by adding guard that the entity is an...

2007-04-20  Gary Dismukes  <dismukes@adacore.com>
	    Eric Botcazou  <ebotcazou@adacore.com>
	    Tristan Gingold  <gingold@adacore.com>
	    Olivier Hainque  <hainque@adacore.com>

	* gigi.h, trans.c (Identifier_to_gnu): Change test for deferred
	constant by adding guard that the entity is an E_Constant before
	testing presence of Full_view (and remove now-unnecessary test that
	entity is not a type).
	For a CONST_DECL used by reference, manually retrieve
	the DECL_INITIAL.  Do not invoke fold in the other DECL_P cases either.
	(struct language_function): Move from utils.c to here.
	(struct parm_attr): New structure.
	(parm_attr, parm_attr vector, parm_attr GC vector): New types.
	(f_parm_attr_cache): New macro.
	(Attribute_to_gnu) <Attr_Length>: When not optimizing, cache the
	expressions for the 'First, 'Last and 'Length attributes of the
	unconstrained array IN parameters.
	(Subprogram_Body_to_gnu): Use gnu_subprog_decl throughout.
	Allocate the information structure for the function earlier, as well
	as the language-specific part.
	If the parameter attributes cache has been populated, evaluate the
	cached expressions on entry.
	(takes_address): Add OPERAND_TYPE parameter.  Handle N_Function_Call,
	N_Procedure_Call_Statement and N_Indexed_Component.
	(Pragma_to_gnu): Translate inspection_point to an asm statement
	containaing a comment and a reference to the object (either its address
	for BLKmode or its value).
	(Identifier_to_gnu): Use TREE_CONSTANT instead of CONST_DECL to decide
	to go to DECL_INITIAL. Together with the size constraint relaxation
	in create_var_decl, enlarges the set of situations in which an
	identifier may be used as an initializer without implying elaboration
	code.
	(Subprogram_Body_to_gnu): Do not fiddle with the debug interface but set
	DECL_IGNORED_P on the function if Needs_Debug_Info is not set on the
	node.
	(maybe_stabilize_reference): Remove lvalues_only parameter.
	(gnat_stabilize_reference): Adjust for above change.
	(gnat_to_gnu): Do not set location information on the result
	if it is a reference.
	(add_cleanup): Add gnat_node parameter and set the location of the
	cleanup to it.
	(Handled_Sequence_Of_Statements_to_gnu): Adjust calls to add_cleanup.
	(Exception_Handler_to_gnu_zcx): Likewise.
	(gigi): Remove the cgraph node if the elaboration procedure is empty.
	(Subprogram_Body_to_gnu): If a stub is attached to the subprogram, emit
	the former right after the latter.
	(start_stmt_group): Make global.
	(end_stmt_group): Likewise.
	(gnu_constraint_error_label_stack, gnu_storage_error_label_stack): New
	vars.
	(gnu_program_error_label_stack): Likewise.
	(gigi): Initialize them.
	(call_to_gnu, gnat_to_gnu, emit_check): Add new arg to build_call_raise.
	(gnat_to_gnu, N_{Push,Pop}_{Constraint,Storage,Program}_Error_Label):
	New cases.
	(push_exception_label_stack): New function.
	(takes_address): New function.

	* utils.c (struct language_function): Move to trans.c from here.
	(unchecked_convert): Do not wrap up integer constants in
	VIEW_CONVERT_EXPRs.
	(create_var_decl_1): Decouple TREE_CONSTANT from CONST_DECL. Prevent
	the latter for aggregate types, unexpected by later passes, and relax an
	arbitrary size constraint on the former.
	(create_field_decl): Use tree_int_cst_equal instead of operand_equal_p
	to compare the sizes.
	(convert_vms_descriptor): When converting to a fat pointer type, be
	prepared for a S descriptor at runtime in spite of a SB specification.
	(shift_unc_components_for_thin_pointers): New function.
	(write_record_type_debug_info): For variable-sized fields, cap the
	alignment of the pointer to the computed alignment.
	(finish_record_type): Change HAS_REP parameter into REP_LEVEL.
	If REP_LEVEL is 2, do not compute the sizes.
	(build_vms_descriptor): Adjust for new prototype of finish_record_type.
	(build_unc_object_type): Likewise.
	(declare_debug_type): New function.

        * ada-tree.def: USE_STMT: removed (not emitted anymore).

        * misc.c (gnat_expand_expr): Call to gnat_expand_stmt removed because
        no statement is expandable anymore.
        (gnat_init_gcc_eh): Do not initialize the DWARF-2 CFI machinery twice.
        (gnat_handle_option): Only allow flag_eliminate_debug_types to be set
        when the user requested it explicitely.
        (gnat_post_options): By default, set flag_eliminate_unused_debug_types
        to 0 for Ada.
        (get_alias_set): Return alias set 0 for a type if
        TYPE_UNIVERSAL_ALIASING_P is set on its main variant.

        * ada-tree.h: (TYPE_UNIVERSAL_ALIASING_P): New macro.
        (DECL_FUNCTION_STUB): New accessor macro.
        (SET_DECL_FUNCTION_STUB): New setter macro.

        * lang.opt (feliminate-unused-debug-types): Intercept this flag for Ada.

	* fe.h (Get_Local_Raise_Call_Entity, Get_RT_Exception_Entity): New
	declarations.

From-SVN: r125371

gcc/ada/ada-tree.def

@@ -80,6 +80,3 @@ DEFTREECODE (REGION_STMT, "region_stmt", tcc_statement, 3)
    handler itself, and HANDLER_STMT_BLOCK is the BLOCK node for this
    binding. */
 DEFTREECODE (HANDLER_STMT, "handler_stmt", tcc_statement, 3)
-
-/* A statement that emits a USE for its single operand.  */
-DEFTREECODE (USE_STMT, "use_expr", tcc_statement, 1)

gcc/ada/ada-tree.h

@@ -6,7 +6,7 @@
  *                                                                          *
  *                              C Header File                               *
  *                                                                          *
- *          Copyright (C) 1992-2006 Free Software Foundation, Inc.          *
+ *          Copyright (C) 1992-2007, Free Software Foundation, Inc.         *
  *                                                                          *
  * GNAT is free software;  you can  redistribute it  and/or modify it under *
  * terms of the  GNU General Public License as published  by the Free Soft- *
@@ -161,6 +161,9 @@ struct lang_type GTY(()) {tree t; };
    padding or alignment.  */
 #define TYPE_IS_PADDING_P(NODE) TYPE_LANG_FLAG_5 (RECORD_TYPE_CHECK (NODE))
 
+/* True if TYPE can alias any other types.  */
+#define TYPE_UNIVERSAL_ALIASING_P(NODE) TYPE_LANG_FLAG_6 (NODE)
+
 /* This field is only defined for FUNCTION_TYPE nodes. If the Ada
    subprogram contains no parameters passed by copy in/copy out then this
    field is 0. Otherwise it points to a list of nodes used to specify the
@@ -288,6 +291,13 @@ struct lang_type GTY(()) {tree t; };
 #define SET_DECL_RENAMED_OBJECT(NODE, X) \
   SET_DECL_LANG_SPECIFIC (VAR_DECL_CHECK (NODE), X)
 
+/* In a FUNCTION_DECL, points to the stub associated with the function
+   if any, otherwise 0.  */
+#define DECL_FUNCTION_STUB(NODE) \
+  GET_DECL_LANG_SPECIFIC (FUNCTION_DECL_CHECK (NODE))
+#define SET_DECL_FUNCTION_STUB(NODE, X) \
+  SET_DECL_LANG_SPECIFIC (FUNCTION_DECL_CHECK (NODE), X)
+
 /* In a FIELD_DECL corresponding to a discriminant, contains the
    discriminant number.  */
 #define DECL_DISCRIMINANT_NUMBER(NODE) DECL_INITIAL (FIELD_DECL_CHECK (NODE))

gcc/ada/fe.h

@@ -100,6 +100,14 @@ extern Entity_Id             Error_Msg_Node_2;
 extern Uint                  Error_Msg_Uint_1;
 extern Uint                  Error_Msg_Uint_2;
 
+/* exp_ch11:  */
+
+#define Get_Local_Raise_Call_Entity exp_ch11__get_local_raise_call_entity
+#define Get_RT_Exception_Entity exp_ch11__get_rt_exception_entity
+
+extern Entity_Id Get_Local_Raise_Call_Entity (void);
+extern Entity_Id Get_RT_Exception_Entity (int);
+
 /* exp_code:  */
 
 #define Asm_Input_Constraint exp_code__asm_input_constraint

gcc/ada/lang.opt

@@ -69,6 +69,12 @@ nostdinc
 Ada RejectNegative
 ; Don't look for source files
 
+feliminate-unused-debug-types
+Ada
+; Effect documented for C - intercepted for Ada to force the associated flag
+; not to be set by default, as it currently eliminates unreferenced parallel
+; types we need for encoding descriptions to the debugger.
+
 nostdlib
 Ada
 ; Don't look for object files

gcc/ada/misc.c

@@ -6,7 +6,7 @@
  *                                                                          *
  *                           C Implementation File                          *
  *                                                                          *
- *          Copyright (C) 1992-2006, Free Software Foundation, Inc.         *
+ *          Copyright (C) 1992-2007, Free Software Foundation, Inc.         *
  *                                                                          *
  * GNAT is free software;  you can  redistribute it  and/or modify it under *
  * terms of the  GNU General Public License as published  by the Free Soft- *
@@ -302,6 +302,14 @@ gnat_handle_option (size_t scode, const char *arg, int value ATTRIBUTE_UNUSED)
       gnat_argc++;
       break;
 
+    case OPT_feliminate_unused_debug_types:
+      /* We arrange for post_option to be able to only set the corresponding
+         flag to 1 when explicitely requested by the user.  We expect the
+         default flag value to be either 0 or positive, and expose a positive
+         -f as a negative value to post_option.  */
+      flag_eliminate_unused_debug_types = -value;
+      break;
+
     case OPT_fRTS_:
       gnat_argv[gnat_argc] = xstrdup ("-fRTS");
       gnat_argc++;
@@ -362,6 +370,14 @@ gnat_post_options (const char **pfilename ATTRIBUTE_UNUSED)
   if (flag_inline_functions)
     flag_inline_trees = 2;
 
+  /* Force eliminate_unused_debug_types to 0 unless an explicit positive
+     -f has been passed.  This forces the default to 0 for Ada, which might
+     differ from the common default.  */
+  if (flag_eliminate_unused_debug_types < 0)
+    flag_eliminate_unused_debug_types = 1;
+  else
+    flag_eliminate_unused_debug_types = 0;
+
   /* The structural alias analysis machinery essentially assumes that
      everything is addressable (modulo bit-fields) by disregarding
      the TYPE_NONALIASED_COMPONENT and DECL_NONADDRESSABLE_P macros.  */
@@ -484,6 +500,11 @@ gnat_compute_largest_alignment (void)
 void
 gnat_init_gcc_eh (void)
 {
+#ifdef DWARF2_UNWIND_INFO
+  /* lang_dependent_init already called dwarf2out_frame_init if true.  */
+  int dwarf2out_frame_initialized = dwarf2out_do_frame ();
+#endif
+
   /* We shouldn't do anything if the No_Exceptions_Handler pragma is set,
      though. This could for instance lead to the emission of tables with
      references to symbols (such as the Ada eh personality routine) within
@@ -517,7 +538,7 @@ gnat_init_gcc_eh (void)
 
   init_eh ();
 #ifdef DWARF2_UNWIND_INFO
-  if (dwarf2out_do_frame ())
+  if (!dwarf2out_frame_initialized && dwarf2out_do_frame ())
     dwarf2out_frame_init ();
 #endif
 }
@@ -633,13 +654,6 @@ gnat_expand_expr (tree exp, rtx target, enum machine_mode tmode,
   tree type = TREE_TYPE (exp);
   tree new;
 
-  /* If this is a statement, call the expansion routine for statements.  */
-  if (IS_STMT (exp))
-    {
-      gnat_expand_stmt (exp);
-      return const0_rtx;
-    }
-
   /* Update EXP to be the new expression to expand.  */
   switch (TREE_CODE (exp))
     {
@@ -746,6 +760,10 @@ gnat_get_alias_set (tree type)
     return
       get_alias_set (TREE_TYPE (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (type)))));
 
+  /* If the type can alias any other types, return the alias set 0.  */
+  else if (TYPE_P (type)
+	   && TYPE_UNIVERSAL_ALIASING_P (TYPE_MAIN_VARIANT (type)))
+    return 0;
 
   return -1;
 }