------------------------------------------------------------------------------ -- -- -- GNAT COMPILER COMPONENTS -- -- -- -- A S P E C T S -- -- -- -- S p e c -- -- -- -- Copyright (C) 2010-2018, 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- -- -- ware Foundation; either version 3, or (at your option) any later ver- -- -- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- -- or FITNESS FOR A PARTICULAR PURPOSE. -- -- -- -- As a special exception under Section 7 of GPL version 3, you are granted -- -- additional permissions described in the GCC Runtime Library Exception, -- -- version 3.1, as published by the Free Software Foundation. -- -- -- -- You should have received a copy of the GNU General Public License and -- -- a copy of the GCC Runtime Library Exception along with this program; -- -- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -- -- . -- -- -- -- GNAT was originally developed by the GNAT team at New York University. -- -- Extensive contributions were provided by Ada Core Technologies Inc. -- -- -- ------------------------------------------------------------------------------ -- This package defines the aspects that are recognized by GNAT in aspect -- specifications. It also contains the subprograms for storing/retrieving -- aspect specifications from the tree. The semantic processing for aspect -- specifications is found in Sem_Ch13.Analyze_Aspect_Specifications. ------------------------ -- Adding New Aspects -- ------------------------ -- In general, each aspect should have a corresponding pragma, so that the -- newly developed functionality is available for Ada versions < Ada 2012. -- When both are defined, it is convenient to first transform the aspect into -- an equivalent pragma in Sem_Ch13.Analyze_Aspect_Specifications, and then -- analyze the pragma in Sem_Prag.Analyze_Pragma. -- To add a new aspect, you need to do the following -- 1. Create a name in snames.ads-tmpl -- 2. Create a value in type Aspect_Id in this unit -- 3. Add a value for the aspect in the global arrays defined in this unit -- 4. Add code for the aspect in Sem_Ch13.Analyze_Aspect_Specifications. -- This may involve adding some nodes to the tree to perform additional -- treatments later. -- 5. If the semantic analysis of expressions/names in the aspect should not -- occur at the point the aspect is defined, add code in the adequate -- semantic analysis procedure for the aspect. For example, this is the -- case for aspects Pre and Post on subprograms, which are pre-analyzed -- at the end of the declaration list to which the subprogram belongs, -- and fully analyzed (possibly with expansion) during the semantic -- analysis of subprogram bodies. with Namet; use Namet; with Snames; use Snames; with Types; use Types; package Aspects is -- Type defining recognized aspects type Aspect_Id is (No_Aspect, -- Dummy entry for no aspect Aspect_Abstract_State, -- GNAT Aspect_Address, Aspect_Alignment, Aspect_Annotate, -- GNAT Aspect_Async_Readers, -- GNAT Aspect_Async_Writers, -- GNAT Aspect_Attach_Handler, Aspect_Bit_Order, Aspect_Component_Size, Aspect_Constant_After_Elaboration, -- GNAT Aspect_Constant_Indexing, Aspect_Contract_Cases, -- GNAT Aspect_Convention, Aspect_CPU, Aspect_Default_Component_Value, Aspect_Default_Initial_Condition, -- GNAT Aspect_Default_Iterator, Aspect_Default_Storage_Pool, Aspect_Default_Value, Aspect_Depends, -- GNAT Aspect_Dimension, -- GNAT Aspect_Dimension_System, -- GNAT Aspect_Dispatching_Domain, Aspect_Dynamic_Predicate, Aspect_Effective_Reads, -- GNAT Aspect_Effective_Writes, -- GNAT Aspect_Extensions_Visible, -- GNAT Aspect_External_Name, Aspect_External_Tag, Aspect_Ghost, -- GNAT Aspect_Global, -- GNAT Aspect_Implicit_Dereference, Aspect_Initial_Condition, -- GNAT Aspect_Initializes, -- GNAT Aspect_Input, Aspect_Interrupt_Priority, Aspect_Invariant, -- GNAT Aspect_Iterator_Element, Aspect_Iterable, -- GNAT Aspect_Link_Name, Aspect_Linker_Section, -- GNAT Aspect_Machine_Radix, Aspect_Max_Queue_Length, -- GNAT Aspect_Object_Size, -- GNAT Aspect_Obsolescent, -- GNAT Aspect_Output, Aspect_Part_Of, -- GNAT Aspect_Post, Aspect_Postcondition, Aspect_Pre, Aspect_Precondition, Aspect_Predicate, -- GNAT Aspect_Predicate_Failure, Aspect_Priority, Aspect_Read, Aspect_Refined_Depends, -- GNAT Aspect_Refined_Global, -- GNAT Aspect_Refined_Post, -- GNAT Aspect_Refined_State, -- GNAT Aspect_Relative_Deadline, Aspect_Scalar_Storage_Order, -- GNAT Aspect_Secondary_Stack_Size, -- GNAT Aspect_Simple_Storage_Pool, -- GNAT Aspect_Size, Aspect_Small, Aspect_SPARK_Mode, -- GNAT Aspect_Static_Predicate, Aspect_Storage_Pool, Aspect_Storage_Size, Aspect_Stream_Size, Aspect_Suppress, Aspect_Synchronization, Aspect_Test_Case, -- GNAT Aspect_Type_Invariant, Aspect_Unimplemented, -- GNAT Aspect_Unsuppress, Aspect_Value_Size, -- GNAT Aspect_Variable_Indexing, Aspect_Volatile_Function, -- GNAT Aspect_Warnings, -- GNAT Aspect_Write, -- The following aspects correspond to library unit pragmas Aspect_All_Calls_Remote, Aspect_Elaborate_Body, Aspect_No_Elaboration_Code_All, -- GNAT Aspect_Preelaborate, Aspect_Pure, Aspect_Remote_Call_Interface, Aspect_Remote_Types, Aspect_Shared_Passive, Aspect_Universal_Data, -- GNAT -- Remaining aspects have a static boolean value that turns the aspect -- on or off. They all correspond to pragmas, but are only converted to -- the pragmas where the value is True. A value of False normally means -- that the aspect is ignored, except in the case of derived types where -- the aspect value is inherited from the parent, in which case, we do -- not allow False if we inherit a True value from the parent. Aspect_Asynchronous, Aspect_Atomic, Aspect_Atomic_Components, Aspect_Disable_Controlled, -- GNAT Aspect_Discard_Names, Aspect_Export, Aspect_Favor_Top_Level, -- GNAT Aspect_Independent, Aspect_Independent_Components, Aspect_Import, Aspect_Inline, Aspect_Inline_Always, -- GNAT Aspect_Interrupt_Handler, Aspect_Lock_Free, -- GNAT Aspect_No_Inline, -- GNAT Aspect_No_Return, Aspect_No_Tagged_Streams, -- GNAT Aspect_Pack, Aspect_Persistent_BSS, -- GNAT Aspect_Preelaborable_Initialization, Aspect_Pure_Function, -- GNAT Aspect_Remote_Access_Type, -- GNAT Aspect_Shared, -- GNAT (equivalent to Atomic) Aspect_Simple_Storage_Pool_Type, -- GNAT Aspect_Suppress_Debug_Info, -- GNAT Aspect_Suppress_Initialization, -- GNAT Aspect_Thread_Local_Storage, -- GNAT Aspect_Unchecked_Union, Aspect_Universal_Aliasing, -- GNAT Aspect_Unmodified, -- GNAT Aspect_Unreferenced, -- GNAT Aspect_Unreferenced_Objects, -- GNAT Aspect_Volatile, Aspect_Volatile_Components, Aspect_Volatile_Full_Access); -- GNAT subtype Aspect_Id_Exclude_No_Aspect is Aspect_Id range Aspect_Id'Succ (No_Aspect) .. Aspect_Id'Last; -- Aspect_Id's excluding No_Aspect -- The following array indicates aspects that accept 'Class Class_Aspect_OK : constant array (Aspect_Id) of Boolean := (Aspect_Input => True, Aspect_Invariant => True, Aspect_Output => True, Aspect_Pre => True, Aspect_Predicate => True, Aspect_Post => True, Aspect_Read => True, Aspect_Write => True, Aspect_Type_Invariant => True, others => False); -- The following array identifies all implementation defined aspects Implementation_Defined_Aspect : constant array (Aspect_Id) of Boolean := (Aspect_Abstract_State => True, Aspect_Annotate => True, Aspect_Async_Readers => True, Aspect_Async_Writers => True, Aspect_Constant_After_Elaboration => True, Aspect_Contract_Cases => True, Aspect_Depends => True, Aspect_Dimension => True, Aspect_Dimension_System => True, Aspect_Effective_Reads => True, Aspect_Effective_Writes => True, Aspect_Extensions_Visible => True, Aspect_Favor_Top_Level => True, Aspect_Ghost => True, Aspect_Global => True, Aspect_Inline_Always => True, Aspect_Invariant => True, Aspect_Lock_Free => True, Aspect_Max_Queue_Length => True, Aspect_Object_Size => True, Aspect_Persistent_BSS => True, Aspect_Predicate => True, Aspect_Pure_Function => True, Aspect_Remote_Access_Type => True, Aspect_Scalar_Storage_Order => True, Aspect_Secondary_Stack_Size => True, Aspect_Shared => True, Aspect_Simple_Storage_Pool => True, Aspect_Simple_Storage_Pool_Type => True, Aspect_Suppress_Debug_Info => True, Aspect_Suppress_Initialization => True, Aspect_Thread_Local_Storage => True, Aspect_Test_Case => True, Aspect_Universal_Aliasing => True, Aspect_Universal_Data => True, Aspect_Unmodified => True, Aspect_Unreferenced => True, Aspect_Unreferenced_Objects => True, Aspect_Value_Size => True, Aspect_Volatile_Function => True, Aspect_Warnings => True, others => False); -- The following array indicates aspects for which multiple occurrences of -- the same aspect attached to the same declaration are allowed. No_Duplicates_Allowed : constant array (Aspect_Id) of Boolean := (Aspect_Annotate => False, Aspect_Test_Case => False, others => True); -- The following subtype defines aspects corresponding to library unit -- pragmas, these can only validly appear as aspects for library units, -- and result in a corresponding pragma being inserted immediately after -- the occurrence of the aspect. subtype Library_Unit_Aspects is Aspect_Id range Aspect_All_Calls_Remote .. Aspect_Universal_Data; -- The following subtype defines aspects accepting an optional static -- boolean parameter indicating if the aspect should be active or -- cancelling. If the parameter is missing the effective value is True, -- enabling the aspect. If the parameter is present it must be a static -- expression of type Standard.Boolean. If the value is True, then the -- aspect is enabled. If it is False, the aspect is disabled. subtype Boolean_Aspects is Aspect_Id range Aspect_Asynchronous .. Aspect_Id'Last; subtype Pre_Post_Aspects is Aspect_Id range Aspect_Post .. Aspect_Precondition; -- The following type is used for indicating allowed expression forms type Aspect_Expression is (Expression, -- Required expression Name, -- Required name Optional_Expression, -- Optional boolean expression Optional_Name); -- Optional name -- The following array indicates what argument type is required Aspect_Argument : constant array (Aspect_Id) of Aspect_Expression := (No_Aspect => Optional_Expression, Aspect_Abstract_State => Expression, Aspect_Address => Expression, Aspect_Alignment => Expression, Aspect_Annotate => Expression, Aspect_Async_Readers => Optional_Expression, Aspect_Async_Writers => Optional_Expression, Aspect_Attach_Handler => Expression, Aspect_Bit_Order => Expression, Aspect_Component_Size => Expression, Aspect_Constant_After_Elaboration => Optional_Expression, Aspect_Constant_Indexing => Name, Aspect_Contract_Cases => Expression, Aspect_Convention => Name, Aspect_CPU => Expression, Aspect_Default_Component_Value => Expression, Aspect_Default_Initial_Condition => Optional_Expression, Aspect_Default_Iterator => Name, Aspect_Default_Storage_Pool => Expression, Aspect_Default_Value => Expression, Aspect_Depends => Expression, Aspect_Dimension => Expression, Aspect_Dimension_System => Expression, Aspect_Dispatching_Domain => Expression, Aspect_Dynamic_Predicate => Expression, Aspect_Effective_Reads => Optional_Expression, Aspect_Effective_Writes => Optional_Expression, Aspect_Extensions_Visible => Optional_Expression, Aspect_External_Name => Expression, Aspect_External_Tag => Expression, Aspect_Ghost => Optional_Expression, Aspect_Global => Expression, Aspect_Implicit_Dereference => Name, Aspect_Initial_Condition => Expression, Aspect_Initializes => Expression, Aspect_Input => Name, Aspect_Interrupt_Priority => Expression, Aspect_Invariant => Expression, Aspect_Iterable => Expression, Aspect_Iterator_Element => Name, Aspect_Link_Name => Expression, Aspect_Linker_Section => Expression, Aspect_Machine_Radix => Expression, Aspect_Max_Queue_Length => Expression, Aspect_Object_Size => Expression, Aspect_Obsolescent => Optional_Expression, Aspect_Output => Name, Aspect_Part_Of => Expression, Aspect_Post => Expression, Aspect_Postcondition => Expression, Aspect_Pre => Expression, Aspect_Precondition => Expression, Aspect_Predicate => Expression, Aspect_Predicate_Failure => Expression, Aspect_Priority => Expression, Aspect_Read => Name, Aspect_Refined_Depends => Expression, Aspect_Refined_Global => Expression, Aspect_Refined_Post => Expression, Aspect_Refined_State => Expression, Aspect_Relative_Deadline => Expression, Aspect_Scalar_Storage_Order => Expression, Aspect_Secondary_Stack_Size => Expression, Aspect_Simple_Storage_Pool => Name, Aspect_Size => Expression, Aspect_Small => Expression, Aspect_SPARK_Mode => Optional_Name, Aspect_Static_Predicate => Expression, Aspect_Storage_Pool => Name, Aspect_Storage_Size => Expression, Aspect_Stream_Size => Expression, Aspect_Suppress => Name, Aspect_Synchronization => Name, Aspect_Test_Case => Expression, Aspect_Type_Invariant => Expression, Aspect_Unimplemented => Optional_Expression, Aspect_Unsuppress => Name, Aspect_Value_Size => Expression, Aspect_Variable_Indexing => Name, Aspect_Volatile_Function => Optional_Expression, Aspect_Warnings => Name, Aspect_Write => Name, Boolean_Aspects => Optional_Expression, Library_Unit_Aspects => Optional_Expression); ----------------------------------------- -- Table Linking Names and Aspect_Id's -- ----------------------------------------- -- Table linking aspect names and id's Aspect_Names : constant array (Aspect_Id) of Name_Id := (No_Aspect => No_Name, Aspect_Abstract_State => Name_Abstract_State, Aspect_Address => Name_Address, Aspect_Alignment => Name_Alignment, Aspect_All_Calls_Remote => Name_All_Calls_Remote, Aspect_Annotate => Name_Annotate, Aspect_Async_Readers => Name_Async_Readers, Aspect_Async_Writers => Name_Async_Writers, Aspect_Asynchronous => Name_Asynchronous, Aspect_Atomic => Name_Atomic, Aspect_Atomic_Components => Name_Atomic_Components, Aspect_Attach_Handler => Name_Attach_Handler, Aspect_Bit_Order => Name_Bit_Order, Aspect_Component_Size => Name_Component_Size, Aspect_Constant_After_Elaboration => Name_Constant_After_Elaboration, Aspect_Constant_Indexing => Name_Constant_Indexing, Aspect_Contract_Cases => Name_Contract_Cases, Aspect_Convention => Name_Convention, Aspect_CPU => Name_CPU, Aspect_Default_Component_Value => Name_Default_Component_Value, Aspect_Default_Initial_Condition => Name_Default_Initial_Condition, Aspect_Default_Iterator => Name_Default_Iterator, Aspect_Default_Storage_Pool => Name_Default_Storage_Pool, Aspect_Default_Value => Name_Default_Value, Aspect_Depends => Name_Depends, Aspect_Dimension => Name_Dimension, Aspect_Dimension_System => Name_Dimension_System, Aspect_Disable_Controlled => Name_Disable_Controlled, Aspect_Discard_Names => Name_Discard_Names, Aspect_Dispatching_Domain => Name_Dispatching_Domain, Aspect_Dynamic_Predicate => Name_Dynamic_Predicate, Aspect_Effective_Reads => Name_Effective_Reads, Aspect_Effective_Writes => Name_Effective_Writes, Aspect_Elaborate_Body => Name_Elaborate_Body, Aspect_Export => Name_Export, Aspect_Extensions_Visible => Name_Extensions_Visible, Aspect_External_Name => Name_External_Name, Aspect_External_Tag => Name_External_Tag, Aspect_Favor_Top_Level => Name_Favor_Top_Level, Aspect_Ghost => Name_Ghost, Aspect_Global => Name_Global, Aspect_Implicit_Dereference => Name_Implicit_Dereference, Aspect_Import => Name_Import, Aspect_Independent => Name_Independent, Aspect_Independent_Components => Name_Independent_Components, Aspect_Inline => Name_Inline, Aspect_Inline_Always => Name_Inline_Always, Aspect_Initial_Condition => Name_Initial_Condition, Aspect_Initializes => Name_Initializes, Aspect_Input => Name_Input, Aspect_Interrupt_Handler => Name_Interrupt_Handler, Aspect_Interrupt_Priority => Name_Interrupt_Priority, Aspect_Invariant => Name_Invariant, Aspect_Iterator_Element => Name_Iterator_Element, Aspect_Iterable => Name_Iterable, Aspect_Link_Name => Name_Link_Name, Aspect_Linker_Section => Name_Linker_Section, Aspect_Lock_Free => Name_Lock_Free, Aspect_Machine_Radix => Name_Machine_Radix, Aspect_Max_Queue_Length => Name_Max_Queue_Length, Aspect_No_Elaboration_Code_All => Name_No_Elaboration_Code_All, Aspect_No_Inline => Name_No_Inline, Aspect_No_Return => Name_No_Return, Aspect_No_Tagged_Streams => Name_No_Tagged_Streams, Aspect_Object_Size => Name_Object_Size, Aspect_Obsolescent => Name_Obsolescent, Aspect_Output => Name_Output, Aspect_Pack => Name_Pack, Aspect_Part_Of => Name_Part_Of, Aspect_Persistent_BSS => Name_Persistent_BSS, Aspect_Post => Name_Post, Aspect_Postcondition => Name_Postcondition, Aspect_Pre => Name_Pre, Aspect_Precondition => Name_Precondition, Aspect_Predicate => Name_Predicate, Aspect_Predicate_Failure => Name_Predicate_Failure, Aspect_Preelaborable_Initialization => Name_Preelaborable_Initialization, Aspect_Preelaborate => Name_Preelaborate, Aspect_Priority => Name_Priority, Aspect_Pure => Name_Pure, Aspect_Pure_Function => Name_Pure_Function, Aspect_Read => Name_Read, Aspect_Refined_Depends => Name_Refined_Depends, Aspect_Refined_Global => Name_Refined_Global, Aspect_Refined_Post => Name_Refined_Post, Aspect_Refined_State => Name_Refined_State, Aspect_Relative_Deadline => Name_Relative_Deadline, Aspect_Remote_Access_Type => Name_Remote_Access_Type, Aspect_Remote_Call_Interface => Name_Remote_Call_Interface, Aspect_Remote_Types => Name_Remote_Types, Aspect_Scalar_Storage_Order => Name_Scalar_Storage_Order, Aspect_Secondary_Stack_Size => Name_Secondary_Stack_Size, Aspect_Shared => Name_Shared, Aspect_Shared_Passive => Name_Shared_Passive, Aspect_Simple_Storage_Pool => Name_Simple_Storage_Pool, Aspect_Simple_Storage_Pool_Type => Name_Simple_Storage_Pool_Type, Aspect_Size => Name_Size, Aspect_Small => Name_Small, Aspect_SPARK_Mode => Name_SPARK_Mode, Aspect_Static_Predicate => Name_Static_Predicate, Aspect_Storage_Pool => Name_Storage_Pool, Aspect_Storage_Size => Name_Storage_Size, Aspect_Stream_Size => Name_Stream_Size, Aspect_Suppress => Name_Suppress, Aspect_Suppress_Debug_Info => Name_Suppress_Debug_Info, Aspect_Suppress_Initialization => Name_Suppress_Initialization, Aspect_Thread_Local_Storage => Name_Thread_Local_Storage, Aspect_Synchronization => Name_Synchronization, Aspect_Test_Case => Name_Test_Case, Aspect_Type_Invariant => Name_Type_Invariant, Aspect_Unchecked_Union => Name_Unchecked_Union, Aspect_Unimplemented => Name_Unimplemented, Aspect_Universal_Aliasing => Name_Universal_Aliasing, Aspect_Universal_Data => Name_Universal_Data, Aspect_Unmodified => Name_Unmodified, Aspect_Unreferenced => Name_Unreferenced, Aspect_Unreferenced_Objects => Name_Unreferenced_Objects, Aspect_Unsuppress => Name_Unsuppress, Aspect_Value_Size => Name_Value_Size, Aspect_Variable_Indexing => Name_Variable_Indexing, Aspect_Volatile => Name_Volatile, Aspect_Volatile_Components => Name_Volatile_Components, Aspect_Volatile_Full_Access => Name_Volatile_Full_Access, Aspect_Volatile_Function => Name_Volatile_Function, Aspect_Warnings => Name_Warnings, Aspect_Write => Name_Write); function Get_Aspect_Id (Name : Name_Id) return Aspect_Id; pragma Inline (Get_Aspect_Id); -- Given a name Nam, returns the corresponding aspect id value. If the name -- does not match any aspect, then No_Aspect is returned as the result. function Get_Aspect_Id (Aspect : Node_Id) return Aspect_Id; pragma Inline (Get_Aspect_Id); -- Given an aspect specification, return the corresponding aspect_id value. -- If the name does not match any aspect, return No_Aspect. ------------------------------------ -- Delaying Evaluation of Aspects -- ------------------------------------ -- The RM requires that all language defined aspects taking an expression -- delay evaluation of the expression till the freeze point of the entity -- to which the aspect applies. This allows forward references, and is of -- use for example in connection with preconditions and postconditions -- where the requirement of making all references in contracts to local -- functions be backwards references would be onerous. -- For consistency, even attributes like Size are delayed, so we can do: -- type A is range 1 .. 10 -- with Size => Not_Defined_Yet; -- .. -- Not_Defined_Yet : constant := 64; -- Resulting in A having a size of 64, which gets set when A is frozen. -- Furthermore, we can have a situation like -- type A is range 1 .. 10 -- with Size => Not_Defined_Yet; -- .. -- type B is new A; -- .. -- Not_Defined_Yet : constant := 64; -- where the Size of A is considered to have been previously specified at -- the point of derivation, even though the actual value of the size is -- not known yet, and in this example B inherits the size value of 64. -- Our normal implementation model (prior to Ada 2012) was simply to copy -- inheritable attributes at the point of derivation. Then any subsequent -- representation items apply either to the parent type, not affecting the -- derived type, or to the derived type, not affecting the parent type. -- To deal with the delayed aspect case, we use two flags. The first is -- set on the parent type if it has delayed representation aspects. This -- flag Has_Delayed_Rep_Aspects indicates that if we derive from this type -- we have to worry about making sure we inherit any delayed aspects. The -- second flag is set on a derived type: May_Have_Inherited_Rep_Aspects -- is set if the parent type has Has_Delayed_Rep_Aspects set. -- When we freeze a derived type, if the May_Have_Inherited_Rep_Aspects -- flag is set, then we call Freeze.Inherit_Delayed_Rep_Aspects when -- the derived type is frozen, which deals with the necessary copying of -- information from the parent type, which must be frozen at that point -- (since freezing the derived type first freezes the parent type). -- SPARK 2014 aspects do not follow the general delay mechanism as they -- act as annotations and cannot modify the attributes of their related -- constructs. To handle forward references in such aspects, the compiler -- delays the analysis of their respective pragmas by collecting them in -- N_Contract nodes. The pragmas are then analyzed at the end of the -- declarative region containing the related construct. For details, -- see routines Analyze_xxx_In_Decl_Part. -- The following shows which aspects are delayed. There are three cases: type Delay_Type is (Always_Delay, -- This aspect is not a representation aspect that can be inherited and -- is always delayed, as required by the language definition. Never_Delay, -- There are two cases. There are language defined aspects like -- Convention where the "expression" is simply an uninterpreted -- identifier, and there is no issue of evaluating it and thus no -- issue of delaying the evaluation. The second case is implementation -- defined aspects where we have decided that we don't want to allow -- delays (and for our own aspects we can do what we like). Rep_Aspect); -- These are the cases of representation aspects that are in general -- delayed, and where there is a potential issue of derived types that -- inherit delayed representation values. -- Note: even if this table indicates that an aspect is delayed, we never -- delay Boolean aspects that have a missing expression (taken as True), -- or expressions for delayed rep items that consist of an integer literal -- (most cases of Size etc. in practice), since in these cases we know we -- can get the value of the expression without delay. Note that we still -- need to delay Boolean aspects that are specifically set to True: -- type R is array (0 .. 31) of Boolean -- with Pack => True; -- True : constant Boolean := False; -- This is nonsense, but we need to make it work and result in R not -- being packed, and if we have something like: -- type R is array (0 .. 31) of Boolean -- with Pack => True; -- RR : R; -- True : constant Boolean := False; -- This is illegal because the visibility of True changes after the freeze -- point, which is not allowed, and we need the delay mechanism to properly -- diagnose this error. Aspect_Delay : constant array (Aspect_Id) of Delay_Type := (No_Aspect => Always_Delay, Aspect_Address => Always_Delay, Aspect_All_Calls_Remote => Always_Delay, Aspect_Asynchronous => Always_Delay, Aspect_Attach_Handler => Always_Delay, Aspect_Constant_Indexing => Always_Delay, Aspect_CPU => Always_Delay, Aspect_Default_Iterator => Always_Delay, Aspect_Default_Storage_Pool => Always_Delay, Aspect_Default_Value => Always_Delay, Aspect_Default_Component_Value => Always_Delay, Aspect_Discard_Names => Always_Delay, Aspect_Dispatching_Domain => Always_Delay, Aspect_Dynamic_Predicate => Always_Delay, Aspect_Elaborate_Body => Always_Delay, Aspect_External_Name => Always_Delay, Aspect_External_Tag => Always_Delay, Aspect_Favor_Top_Level => Always_Delay, Aspect_Implicit_Dereference => Always_Delay, Aspect_Independent => Always_Delay, Aspect_Independent_Components => Always_Delay, Aspect_Inline => Always_Delay, Aspect_Inline_Always => Always_Delay, Aspect_Input => Always_Delay, Aspect_Interrupt_Handler => Always_Delay, Aspect_Interrupt_Priority => Always_Delay, Aspect_Invariant => Always_Delay, Aspect_Iterable => Always_Delay, Aspect_Iterator_Element => Always_Delay, Aspect_Link_Name => Always_Delay, Aspect_Linker_Section => Always_Delay, Aspect_Lock_Free => Always_Delay, Aspect_No_Inline => Always_Delay, Aspect_No_Return => Always_Delay, Aspect_Output => Always_Delay, Aspect_Persistent_BSS => Always_Delay, Aspect_Post => Always_Delay, Aspect_Postcondition => Always_Delay, Aspect_Pre => Always_Delay, Aspect_Precondition => Always_Delay, Aspect_Predicate => Always_Delay, Aspect_Predicate_Failure => Always_Delay, Aspect_Preelaborable_Initialization => Always_Delay, Aspect_Preelaborate => Always_Delay, Aspect_Priority => Always_Delay, Aspect_Pure => Always_Delay, Aspect_Pure_Function => Always_Delay, Aspect_Read => Always_Delay, Aspect_Relative_Deadline => Always_Delay, Aspect_Remote_Access_Type => Always_Delay, Aspect_Remote_Call_Interface => Always_Delay, Aspect_Remote_Types => Always_Delay, Aspect_Secondary_Stack_Size => Always_Delay, Aspect_Shared => Always_Delay, Aspect_Shared_Passive => Always_Delay, Aspect_Simple_Storage_Pool => Always_Delay, Aspect_Simple_Storage_Pool_Type => Always_Delay, Aspect_Static_Predicate => Always_Delay, Aspect_Storage_Pool => Always_Delay, Aspect_Stream_Size => Always_Delay, Aspect_Suppress => Always_Delay, Aspect_Suppress_Debug_Info => Always_Delay, Aspect_Suppress_Initialization => Always_Delay, Aspect_Thread_Local_Storage => Always_Delay, Aspect_Type_Invariant => Always_Delay, Aspect_Unchecked_Union => Always_Delay, Aspect_Universal_Aliasing => Always_Delay, Aspect_Universal_Data => Always_Delay, Aspect_Unmodified => Always_Delay, Aspect_Unreferenced => Always_Delay, Aspect_Unreferenced_Objects => Always_Delay, Aspect_Unsuppress => Always_Delay, Aspect_Variable_Indexing => Always_Delay, Aspect_Write => Always_Delay, Aspect_Abstract_State => Never_Delay, Aspect_Annotate => Never_Delay, Aspect_Async_Readers => Never_Delay, Aspect_Async_Writers => Never_Delay, Aspect_Constant_After_Elaboration => Never_Delay, Aspect_Contract_Cases => Never_Delay, Aspect_Convention => Never_Delay, Aspect_Default_Initial_Condition => Never_Delay, Aspect_Depends => Never_Delay, Aspect_Dimension => Never_Delay, Aspect_Dimension_System => Never_Delay, Aspect_Disable_Controlled => Never_Delay, Aspect_Effective_Reads => Never_Delay, Aspect_Effective_Writes => Never_Delay, Aspect_Export => Never_Delay, Aspect_Extensions_Visible => Never_Delay, Aspect_Ghost => Never_Delay, Aspect_Global => Never_Delay, Aspect_Import => Never_Delay, Aspect_Initial_Condition => Never_Delay, Aspect_Initializes => Never_Delay, Aspect_Max_Queue_Length => Never_Delay, Aspect_No_Elaboration_Code_All => Never_Delay, Aspect_No_Tagged_Streams => Never_Delay, Aspect_Obsolescent => Never_Delay, Aspect_Part_Of => Never_Delay, Aspect_Refined_Depends => Never_Delay, Aspect_Refined_Global => Never_Delay, Aspect_Refined_Post => Never_Delay, Aspect_Refined_State => Never_Delay, Aspect_SPARK_Mode => Never_Delay, Aspect_Synchronization => Never_Delay, Aspect_Test_Case => Never_Delay, Aspect_Unimplemented => Never_Delay, Aspect_Volatile_Function => Never_Delay, Aspect_Warnings => Never_Delay, Aspect_Alignment => Rep_Aspect, Aspect_Atomic => Rep_Aspect, Aspect_Atomic_Components => Rep_Aspect, Aspect_Bit_Order => Rep_Aspect, Aspect_Component_Size => Rep_Aspect, Aspect_Machine_Radix => Rep_Aspect, Aspect_Object_Size => Rep_Aspect, Aspect_Pack => Rep_Aspect, Aspect_Scalar_Storage_Order => Rep_Aspect, Aspect_Size => Rep_Aspect, Aspect_Small => Rep_Aspect, Aspect_Storage_Size => Rep_Aspect, Aspect_Value_Size => Rep_Aspect, Aspect_Volatile => Rep_Aspect, Aspect_Volatile_Components => Rep_Aspect, Aspect_Volatile_Full_Access => Rep_Aspect); ------------------------------------------------ -- Handling of Aspect Specifications on Stubs -- ------------------------------------------------ -- Aspects that appear on the following stub nodes -- N_Package_Body_Stub -- N_Protected_Body_Stub -- N_Subprogram_Body_Stub -- N_Task_Body_Stub -- are treated as if they apply to the corresponding proper body. Their -- analysis is postponed until the analysis of the proper body takes place -- (see Analyze_Proper_Body). The delay is required because the analysis -- may generate extra code which would be harder to relocate to the body. -- If the proper body is present, the aspect specifications are relocated -- to the corresponding body node: -- N_Package_Body -- N_Protected_Body -- N_Subprogram_Body -- N_Task_Body -- The subsequent analysis takes care of the aspect-to-pragma conversions -- and verification of pragma legality. In the case where the proper body -- is not available, the aspect specifications are analyzed on the spot -- (see Analyze_Proper_Body) to catch potential errors. -- The following table lists all aspects that can apply to a subprogram -- body [stub]. For instance, the following example is legal: -- package P with SPARK_Mode ...; -- package body P with SPARK_Mode is ...; -- The table should be synchronized with Pragma_On_Body_Or_Stub_OK in unit -- Sem_Prag. Aspect_On_Body_Or_Stub_OK : constant array (Aspect_Id) of Boolean := (Aspect_Refined_Depends => True, Aspect_Refined_Global => True, Aspect_Refined_Post => True, Aspect_SPARK_Mode => True, Aspect_Warnings => True, others => False); ------------------------------------------------------------------- -- Handling of Aspects Specifications on Single Concurrent Types -- ------------------------------------------------------------------- -- Certain aspects that appear on the following nodes -- N_Single_Protected_Declaration -- N_Single_Task_Declaration -- are treated as if they apply to the anonymous object produced by the -- analysis of a single concurrent type. The following table lists all -- aspects that should apply to the anonymous object. The table should -- be synchronized with Pragma_On_Anonymous_Object_OK in unit Sem_Prag. Aspect_On_Anonymous_Object_OK : constant array (Aspect_Id) of Boolean := (Aspect_Depends => True, Aspect_Global => True, Aspect_Part_Of => True, others => False); --------------------------------------------------- -- Handling of Aspect Specifications in the Tree -- --------------------------------------------------- -- Several kinds of declaration node permit aspect specifications in Ada -- 2012 mode. If there was room in all the corresponding declaration nodes, -- we could just have a field Aspect_Specifications pointing to a list of -- nodes for the aspects (N_Aspect_Specification nodes). But there isn't -- room, so we adopt a different approach. -- The following subprograms provide access to a specialized interface -- implemented internally with a hash table in the body, that provides -- access to aspect specifications. function Aspect_Specifications (N : Node_Id) return List_Id; -- Given a node N, returns the list of N_Aspect_Specification nodes that -- are attached to this declaration node. If the node is in the class of -- declaration nodes that permit aspect specifications, as defined by the -- predicate above, and if their Has_Aspects flag is set to True, then this -- will always be a non-empty list. If this flag is set to False, then -- No_List is returned. Normally, the only nodes that have Has_Aspects set -- True are the nodes for which Permits_Aspect_Specifications would return -- True (i.e. the declaration nodes defined in the RM as permitting the -- presence of Aspect_Specifications). However, it is possible for the -- flag Has_Aspects to be set on other nodes as a result of Rewrite and -- Replace calls, and this function may be used to retrieve the aspect -- specifications for the original rewritten node in such cases. function Aspects_On_Body_Or_Stub_OK (N : Node_Id) return Boolean; -- N denotes a body [stub] with aspects. Determine whether all aspects of N -- are allowed to appear on a body [stub]. procedure Exchange_Aspects (N1 : Node_Id; N2 : Node_Id); -- Exchange the aspect specifications of two nodes. If either node lacks an -- aspect specification list, the routine has no effect. It is assumed that -- both nodes can support aspects. function Find_Aspect (Id : Entity_Id; A : Aspect_Id) return Node_Id; -- Find the aspect specification of aspect A associated with entity I. -- Return Empty if Id does not have the requested aspect. function Find_Value_Of_Aspect (Id : Entity_Id; A : Aspect_Id) return Node_Id; -- Find the value of aspect A associated with entity Id. Return Empty if -- Id does not have the requested aspect. function Has_Aspect (Id : Entity_Id; A : Aspect_Id) return Boolean; -- Determine whether entity Id has aspect A procedure Move_Aspects (From : Node_Id; To : Node_Id); -- Relocate the aspect specifications of node From to node To. On entry it -- is assumed that To does not have aspect specifications. If From has no -- aspects, the routine has no effect. procedure Move_Or_Merge_Aspects (From : Node_Id; To : Node_Id); -- Relocate the aspect specifications of node From to node To. If To has -- aspects, the aspects of From are appended to the aspects of To. If From -- has no aspects, the routine has no effect. Special behavior: -- * When node From denotes a subprogram body stub without a previous -- declaration, the only aspects relocated to node To are those found -- in table Aspect_On_Body_Or_Stub_OK. -- * When node From denotes a single synchronized type declaration, the -- only aspects relocated to node To are those found in table -- Aspect_On_Anonymous_Object_OK. function Permits_Aspect_Specifications (N : Node_Id) return Boolean; -- Returns True if the node N is a declaration node that permits aspect -- specifications in the grammar. It is possible for other nodes to have -- aspect specifications as a result of Rewrite or Replace calls. procedure Remove_Aspects (N : Node_Id); -- Delete the aspect specifications associated with node N. If the node has -- no aspects, the routine has no effect. function Same_Aspect (A1 : Aspect_Id; A2 : Aspect_Id) return Boolean; -- Returns True if A1 and A2 are (essentially) the same aspect. This is not -- a simple equality test because e.g. Post and Postcondition are the same. -- This is used for detecting duplicate aspects. procedure Set_Aspect_Specifications (N : Node_Id; L : List_Id); -- The node N must be in the class of declaration nodes that permit aspect -- specifications and the Has_Aspects flag must be False on entry. L must -- be a non-empty list of N_Aspect_Specification nodes. This procedure sets -- the Has_Aspects flag to True, and makes an entry that can be retrieved -- by a subsequent Aspect_Specifications call. It is an error to call this -- procedure with a node that does not permit aspect specifications, or a -- node that has its Has_Aspects flag set True on entry, or with L being an -- empty list or No_List. procedure Tree_Read; -- Reads contents of Aspect_Specifications hash table from the tree file procedure Tree_Write; -- Writes contents of Aspect_Specifications hash table to the tree file end Aspects;