diff options
Diffstat (limited to 'gcc/ada/gcc-interface/decl.c')
| -rw-r--r-- | gcc/ada/gcc-interface/decl.c | 150 |
1 files changed, 81 insertions, 69 deletions
diff --git a/gcc/ada/gcc-interface/decl.c b/gcc/ada/gcc-interface/decl.c index e226f256b47..d2316afc8f1 100644 --- a/gcc/ada/gcc-interface/decl.c +++ b/gcc/ada/gcc-interface/decl.c @@ -206,7 +206,6 @@ static tree gnat_to_gnu_component_type (Entity_Id, bool, bool); static tree gnat_to_gnu_subprog_type (Entity_Id, bool, bool, tree *); static tree gnat_to_gnu_field (Entity_Id, tree, int, bool, bool); static tree gnu_ext_name_for_subprog (Entity_Id, tree); -static tree change_qualified_type (tree, int); static void set_nonaliased_component_on_array_type (tree); static void set_reverse_storage_order_on_array_type (tree); static bool same_discriminant_p (Entity_Id, Entity_Id); @@ -592,17 +591,22 @@ gnat_to_gnu_entity (Entity_Id gnat_entity, tree gnu_expr, bool definition) /* If we have a constant that we are not defining, get the expression it was defined to represent. This is necessary to avoid generating dumb elaboration code in simple cases, but we may throw it away later if it - is not a constant. But do not retrieve it if it is an allocator since - the designated type might still be dummy at this point. */ + is not a constant. But do not do it for dispatch tables because they + are only referenced indirectly and we need to have a consistent view + of the exported and of the imported declarations of the tables from + external units for them to be properly merged in LTO mode. Moreover + simply do not retrieve the expression it if it is an allocator since + the designated type might still be dummy at this point. Note that we + invoke gnat_to_gnu_external and not gnat_to_gnu because the expression + may contain N_Expression_With_Actions nodes and thus declarations of + objects from other units that we need to discard. */ if (!definition && !No_Initialization (Declaration_Node (gnat_entity)) - && Present (Expression (Declaration_Node (gnat_entity))) - && Nkind (Expression (Declaration_Node (gnat_entity))) - != N_Allocator) - /* The expression may contain N_Expression_With_Actions nodes and - thus object declarations from other units. Discard them. */ - gnu_expr - = gnat_to_gnu_external (Expression (Declaration_Node (gnat_entity))); + && !Is_Dispatch_Table_Entity (gnat_entity) + && Present (gnat_temp = Expression (Declaration_Node (gnat_entity))) + && Nkind (gnat_temp) != N_Allocator + && (!type_annotate_only || Compile_Time_Known_Value (gnat_temp))) + gnu_expr = gnat_to_gnu_external (gnat_temp); /* ... fall through ... */ @@ -2063,11 +2067,16 @@ gnat_to_gnu_entity (Entity_Id gnat_entity, tree gnu_expr, bool definition) { gnu_fat_type = TYPE_MAIN_VARIANT (TYPE_POINTER_TO (gnu_type)); TYPE_NAME (gnu_fat_type) = NULL_TREE; - /* Save the contents of the dummy type for update_pointer_to. */ - TYPE_POINTER_TO (gnu_type) = copy_type (gnu_fat_type); gnu_ptr_template = - TREE_TYPE (TREE_CHAIN (TYPE_FIELDS (gnu_fat_type))); + TREE_TYPE (DECL_CHAIN (TYPE_FIELDS (gnu_fat_type))); gnu_template_type = TREE_TYPE (gnu_ptr_template); + + /* Save the contents of the dummy type for update_pointer_to. */ + TYPE_POINTER_TO (gnu_type) = copy_type (gnu_fat_type); + TYPE_FIELDS (TYPE_POINTER_TO (gnu_type)) + = copy_node (TYPE_FIELDS (gnu_fat_type)); + DECL_CHAIN (TYPE_FIELDS (TYPE_POINTER_TO (gnu_type))) + = copy_node (DECL_CHAIN (TYPE_FIELDS (gnu_fat_type))); } else { @@ -2088,29 +2097,39 @@ gnat_to_gnu_entity (Entity_Id gnat_entity, tree gnu_expr, bool definition) /* Build the fat pointer type. Use a "void *" object instead of a pointer to the array type since we don't have the array type - yet (it will reference the fat pointer via the bounds). */ - tem - = create_field_decl (get_identifier ("P_ARRAY"), ptr_type_node, - gnu_fat_type, NULL_TREE, NULL_TREE, 0, 0); - DECL_CHAIN (tem) - = create_field_decl (get_identifier ("P_BOUNDS"), gnu_ptr_template, - gnu_fat_type, NULL_TREE, NULL_TREE, 0, 0); - + yet (it will reference the fat pointer via the bounds). Note + that we reuse the existing fields of a dummy type because for: + + type Arr is array (Positive range <>) of Element_Type; + type Array_Ref is access Arr; + Var : Array_Ref := Null; + + in a declarative part, Arr will be frozen only after Var, which + means that the fields used in the CONSTRUCTOR built for Null are + those of the dummy type, which in turn means that COMPONENT_REFs + of Var may be built with these fields. Now if COMPONENT_REFs of + Var are also built later with the fields of the final type, the + aliasing machinery may consider that the accesses are distinct + if the FIELD_DECLs are distinct as objects. */ if (COMPLETE_TYPE_P (gnu_fat_type)) { - /* We are going to lay it out again so reset the alias set. */ - alias_set_type alias_set = TYPE_ALIAS_SET (gnu_fat_type); - TYPE_ALIAS_SET (gnu_fat_type) = -1; - finish_fat_pointer_type (gnu_fat_type, tem); - TYPE_ALIAS_SET (gnu_fat_type) = alias_set; + tem = TYPE_FIELDS (gnu_fat_type); + TREE_TYPE (tem) = ptr_type_node; + TREE_TYPE (DECL_CHAIN (tem)) = gnu_ptr_template; + TYPE_DECL_SUPPRESS_DEBUG (TYPE_STUB_DECL (gnu_fat_type)) = 0; for (t = gnu_fat_type; t; t = TYPE_NEXT_VARIANT (t)) - { - TYPE_FIELDS (t) = tem; - SET_TYPE_UNCONSTRAINED_ARRAY (t, gnu_type); - } + SET_TYPE_UNCONSTRAINED_ARRAY (t, gnu_type); } else { + tem + = create_field_decl (get_identifier ("P_ARRAY"), + ptr_type_node, gnu_fat_type, + NULL_TREE, NULL_TREE, 0, 0); + DECL_CHAIN (tem) + = create_field_decl (get_identifier ("P_BOUNDS"), + gnu_ptr_template, gnu_fat_type, + NULL_TREE, NULL_TREE, 0, 0); finish_fat_pointer_type (gnu_fat_type, tem); SET_TYPE_UNCONSTRAINED_ARRAY (gnu_fat_type, gnu_type); } @@ -3389,20 +3408,6 @@ gnat_to_gnu_entity (Entity_Id gnat_entity, tree gnu_expr, bool definition) break; } - /* If this is a record subtype associated with a dispatch table, - strip the suffix. This is necessary to make sure 2 different - subtypes associated with the imported and exported views of a - dispatch table are properly merged in LTO mode. */ - if (Is_Dispatch_Table_Entity (gnat_entity)) - { - char *p; - Get_Encoded_Name (gnat_entity); - p = strchr (Name_Buffer, '_'); - gcc_assert (p); - strcpy (p+2, "dtS"); - gnu_entity_name = get_identifier (Name_Buffer); - } - /* When the subtype has discriminants and these discriminants affect the initial shape it has inherited, factor them in. But for an Unchecked_Union (it must be an Itype), just return the type. @@ -4681,7 +4686,7 @@ gnat_to_gnu_entity (Entity_Id gnat_entity, tree gnu_expr, bool definition) /* If this is not an unconstrained array type, set some flags. */ if (TREE_CODE (gnu_type) != UNCONSTRAINED_ARRAY_TYPE) { - /* Tell the middle-end that objects of tagged types are guaranteed to + /* Record the property that objects of tagged types are guaranteed to be properly aligned. This is necessary because conversions to the class-wide type are translated into conversions to the root type, which can be less aligned than some of its derived types. */ @@ -5272,17 +5277,6 @@ gnat_to_gnu_component_type (Entity_Id gnat_array, bool definition, Is_Bit_Packed_Array (gnat_array) ? TYPE_DECL : VAR_DECL, true, Has_Component_Size_Clause (gnat_array)); - /* If the array has aliased components and the component size can be zero, - force at least unit size to ensure that the components have distinct - addresses. */ - if (!gnu_comp_size - && Has_Aliased_Components (gnat_array) - && (integer_zerop (TYPE_SIZE (gnu_type)) - || (TREE_CODE (gnu_type) == ARRAY_TYPE - && !TREE_CONSTANT (TYPE_SIZE (gnu_type))))) - gnu_comp_size - = size_binop (MAX_EXPR, TYPE_SIZE (gnu_type), bitsize_unit_node); - /* If the component type is a RECORD_TYPE that has a self-referential size, then use the maximum size for the component size. */ if (!gnu_comp_size @@ -5290,6 +5284,13 @@ gnat_to_gnu_component_type (Entity_Id gnat_array, bool definition, && CONTAINS_PLACEHOLDER_P (TYPE_SIZE (gnu_type))) gnu_comp_size = max_size (TYPE_SIZE (gnu_type), true); + /* If the array has aliased components and the component size is zero, force + the unit size to ensure that the components have distinct addresses. */ + if (!gnu_comp_size + && Has_Aliased_Components (gnat_array) + && integer_zerop (TYPE_SIZE (gnu_type))) + gnu_comp_size = bitsize_unit_node; + /* Honor the component size. This is not needed for bit-packed arrays. */ if (gnu_comp_size && !Is_Bit_Packed_Array (gnat_array)) { @@ -5312,6 +5313,30 @@ gnat_to_gnu_component_type (Entity_Id gnat_array, bool definition, gnat_array); } + /* This is a very special case where the array has aliased components and the + component size might be zero at run time. As explained above, we force at + least the unit size but we don't want to build a distinct padding type for + each invocation (they are not canonicalized if they have variable size) so + we cache this special padding type as TYPE_PADDING_FOR_COMPONENT. */ + else if (Has_Aliased_Components (gnat_array) + && TREE_CODE (gnu_type) == ARRAY_TYPE + && !TREE_CONSTANT (TYPE_SIZE (gnu_type))) + { + if (TYPE_PADDING_FOR_COMPONENT (gnu_type)) + gnu_type = TYPE_PADDING_FOR_COMPONENT (gnu_type); + else + { + gnu_comp_size + = size_binop (MAX_EXPR, TYPE_SIZE (gnu_type), bitsize_unit_node); + TYPE_PADDING_FOR_COMPONENT (gnu_type) + = maybe_pad_type (gnu_type, gnu_comp_size, 0, gnat_array, + true, false, definition, true); + gnu_type = TYPE_PADDING_FOR_COMPONENT (gnu_type); + create_type_decl (TYPE_NAME (gnu_type), gnu_type, true, debug_info_p, + gnat_array); + } + } + /* If the component type is a padded type made for a non-bit-packed array of scalars with reverse storage order, we need to propagate the reverse storage order to the padding type since it is the innermost enclosing @@ -6276,19 +6301,6 @@ gnu_ext_name_for_subprog (Entity_Id gnat_subprog, tree gnu_entity_name) return gnu_ext_name; } -/* Like build_qualified_type, but TYPE_QUALS is added to the existing - qualifiers on TYPE. */ - -static tree -change_qualified_type (tree type, int type_quals) -{ - /* Qualifiers must be put on the associated array type. */ - if (TREE_CODE (type) == UNCONSTRAINED_ARRAY_TYPE) - return type; - - return build_qualified_type (type, TYPE_QUALS (type) | type_quals); -} - /* Set TYPE_NONALIASED_COMPONENT on an array type built by means of build_nonshared_array_type. */ |