OpenE2K/gcc
2
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

[Ada] Improve code generated for aggregates of VFA type

Browse Source 
This avoids using a full access for constants internally generated from
assignments of aggregates with a Volatile_Full_Access type.

gcc/ada/

	* gcc-interface/gigi.h (simple_constant_p): Declare.
	* gcc-interface/decl.cc (gnat_to_gnu_entity) <E_Variable>: Strip
	the qualifiers from the type of a simple constant.
	(simple_constant_p): New predicate.
	* gcc-interface/trans.cc (node_is_atomic): Return true for objects
	with atomic type except for simple constants.
	(node_is_volatile_full_access): Return false for simple constants
	with VFA type.
This commit is contained in:
Eric Botcazou 2022-06-07 21:46:04 +02:00 committed by Pierre-Marie de Rodat
parent 40242ebb71
commit 1141fbd71e
3 changed files with 29 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

20
gcc/ada/gcc-interface/decl.cc
View File

@ -660,8 +660,8 @@ gnat_to_gnu_entity (Entity_Id gnat_entity, tree gnu_expr, bool definition)
like variables. */
if (definition
&& !gnu_expr
&& No (Address_Clause (gnat_entity))
&& !No_Initialization (gnat_decl)
&& No (Address_Clause (gnat_entity))
&& No (gnat_renamed_obj))
{
gnu_decl = error_mark_node;
@ -781,6 +781,11 @@ gnat_to_gnu_entity (Entity_Id gnat_entity, tree gnu_expr, bool definition)
if (kind == E_Loop_Parameter)
gnu_type = get_base_type (gnu_type);
/* If this is a simple constant, strip the qualifiers from its type,
since the constant represents only its value. */
else if (simple_constant_p (gnat_entity))
gnu_type = TYPE_MAIN_VARIANT (gnu_type);
/* Reject non-renamed objects whose type is an unconstrained array or
any object whose type is a dummy type or void. */
if ((TREE_CODE (gnu_type) == UNCONSTRAINED_ARRAY_TYPE
@ -9541,6 +9546,19 @@ promote_object_alignment (tree gnu_type, tree gnu_size, Entity_Id gnat_entity)
return align;
}
/* Return whether GNAT_ENTITY is a simple constant, i.e. it represents only
its value and reading it has no side effects. */
bool
simple_constant_p (Entity_Id gnat_entity)
{
return Ekind (gnat_entity) == E_Constant
&& Present (Constant_Value (gnat_entity))
&& !No_Initialization (gnat_entity)
&& No (Address_Clause (gnat_entity))
&& No (Renamed_Object (gnat_entity));
}
/* Verify that TYPE is something we can implement atomically. If not, issue
an error for GNAT_ENTITY. COMPONENT_P is true if we are being called to
process a component type. */

4
gcc/ada/gcc-interface/gigi.h
View File

@ -998,6 +998,10 @@ extern Entity_Id get_debug_scope (Node_Id gnat_node, bool *is_subprogram);
should be synchronized with Exp_Dbug.Debug_Renaming_Declaration. */
extern bool can_materialize_object_renaming_p (Node_Id expr);
/* Return whether GNAT_ENTITY is a simple constant, i.e. it represents only
its value and reading it has no side effects. */
extern bool simple_constant_p (Entity_Id gnat_entity);
/* Return the size of TYPE, which must be a positive power of 2. */
extern unsigned int resolve_atomic_size (tree type);

9
gcc/ada/gcc-interface/trans.cc
View File

@ -4111,9 +4111,11 @@ node_is_atomic (Node_Id gnat_node)
case N_Identifier:
case N_Expanded_Name:
gnat_entity = Entity (gnat_node);
if (Ekind (gnat_entity) != E_Variable)
if (!Is_Object (gnat_entity))
break;
return Is_Atomic (gnat_entity) || Is_Atomic (Etype (gnat_entity));
return Is_Atomic (gnat_entity)
|| (Is_Atomic (Etype (gnat_entity))
&& !simple_constant_p (gnat_entity));
case N_Selected_Component:
return Is_Atomic (Etype (gnat_node))
@ -4152,7 +4154,8 @@ node_is_volatile_full_access (Node_Id gnat_node)
if (!Is_Object (gnat_entity))
break;
return Is_Volatile_Full_Access (gnat_entity)
|| Is_Volatile_Full_Access (Etype (gnat_entity));
|| (Is_Volatile_Full_Access (Etype (gnat_entity))
&& !simple_constant_p (gnat_entity));
case N_Selected_Component:
return Is_Volatile_Full_Access (Etype (gnat_node))