| ------------------------------------------------------------------------------ |
| -- -- |
| -- GNAT COMPILER COMPONENTS -- |
| -- -- |
| -- S E M _ U T I L -- |
| -- -- |
| -- S p e c -- |
| -- -- |
| -- Copyright (C) 1992-2006, 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 2, 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. See the GNU General Public License -- |
| -- for more details. You should have received a copy of the GNU General -- |
| -- Public License distributed with GNAT; see file COPYING. If not, write -- |
| -- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, -- |
| -- Boston, MA 02110-1301, USA. -- |
| -- -- |
| -- GNAT was originally developed by the GNAT team at New York University. -- |
| -- Extensive contributions were provided by Ada Core Technologies Inc. -- |
| -- -- |
| ------------------------------------------------------------------------------ |
| |
| -- Package containing utility procedures used throughout the semantics |
| |
| with Einfo; use Einfo; |
| with Types; use Types; |
| with Uintp; use Uintp; |
| with Urealp; use Urealp; |
| |
| package Sem_Util is |
| |
| procedure Add_Access_Type_To_Process (E : Entity_Id; A : Entity_Id); |
| -- Add A to the list of access types to process when expanding the |
| -- freeze node of E. |
| |
| function Alignment_In_Bits (E : Entity_Id) return Uint; |
| -- If the alignment of the type or object E is currently known to the |
| -- compiler, then this function returns the alignment value in bits. |
| -- Otherwise Uint_0 is returned, indicating that the alignment of the |
| -- entity is not yet known to the compiler. |
| |
| procedure Apply_Compile_Time_Constraint_Error |
| (N : Node_Id; |
| Msg : String; |
| Reason : RT_Exception_Code; |
| Ent : Entity_Id := Empty; |
| Typ : Entity_Id := Empty; |
| Loc : Source_Ptr := No_Location; |
| Rep : Boolean := True; |
| Warn : Boolean := False); |
| -- N is a subexpression which will raise constraint error when evaluated |
| -- at runtime. Msg is a message that explains the reason for raising the |
| -- exception. The last character is ? if the message is always a warning, |
| -- even in Ada 95, and is not a ? if the message represents an illegality |
| -- (because of violation of static expression rules) in Ada 95 (but not |
| -- in Ada 83). Typically this routine posts all messages at the Sloc of |
| -- node N. However, if Loc /= No_Location, Loc is the Sloc used to output |
| -- the message. After posting the appropriate message, and if the flag |
| -- Rep is set, this routine replaces the expression with an appropriate |
| -- N_Raise_Constraint_Error node using the given Reason code. This node |
| -- is then marked as being static if the original node is static, but |
| -- sets the flag Raises_Constraint_Error, preventing further evaluation. |
| -- The error message may contain a } or & insertion character. This |
| -- normally references Etype (N), unless the Ent argument is given |
| -- explicitly, in which case it is used instead. The type of the raise |
| -- node that is built is normally Etype (N), but if the Typ parameter |
| -- is present, this is used instead. Warn is normally False. If it is |
| -- True then the message is treated as a warning even though it does |
| -- not end with a ? (this is used when the caller wants to parametrize |
| -- whether an error or warning is given. |
| |
| function Build_Actual_Subtype |
| (T : Entity_Id; |
| N : Node_Or_Entity_Id) return Node_Id; |
| -- Build an anonymous subtype for an entity or expression, using the |
| -- bounds of the entity or the discriminants of the enclosing record. |
| -- T is the type for which the actual subtype is required, and N is either |
| -- a defining identifier, or any subexpression. |
| |
| function Build_Actual_Subtype_Of_Component |
| (T : Entity_Id; |
| N : Node_Id) return Node_Id; |
| -- Determine whether a selected component has a type that depends on |
| -- discriminants, and build actual subtype for it if so. |
| |
| function Build_Discriminal_Subtype_Of_Component |
| (T : Entity_Id) return Node_Id; |
| -- Determine whether a record component has a type that depends on |
| -- discriminants, and build actual subtype for it if so. |
| |
| procedure Build_Elaboration_Entity (N : Node_Id; Spec_Id : Entity_Id); |
| -- Given a compilation unit node N, allocate an elaboration boolean for |
| -- the compilation unit, and install it in the Elaboration_Entity field |
| -- of Spec_Id, the entity for the compilation unit. |
| |
| function Cannot_Raise_Constraint_Error (Expr : Node_Id) return Boolean; |
| -- Returns True if the expression cannot possibly raise Constraint_Error. |
| -- The response is conservative in the sense that a result of False does |
| -- not necessarily mean that CE could be raised, but a response of True |
| -- means that for sure CE cannot be raised. |
| |
| procedure Check_Fully_Declared (T : Entity_Id; N : Node_Id); |
| -- Verify that the full declaration of type T has been seen. If not, |
| -- place error message on node N. Used in object declarations, type |
| -- conversions, qualified expressions. |
| |
| procedure Check_Obsolescent (Nam : Entity_Id; N : Node_Id); |
| -- Nam is either a subprogram or a (generic) package entity. This procedure |
| -- checks if the Is_Obsolescent flag is set and if so, outputs appropriate |
| -- diagnostics (it also checks the appropriate restriction). N is the node |
| -- to which error messages are attached. |
| |
| procedure Check_Potentially_Blocking_Operation (N : Node_Id); |
| -- N is one of the statement forms that is a potentially blocking |
| -- operation. If it appears within a protected action, emit warning. |
| |
| procedure Check_VMS (Construct : Node_Id); |
| -- Check that this the target is OpenVMS, and if so, return with |
| -- no effect, otherwise post an error noting this can only be used |
| -- with OpenVMS ports. The argument is the construct in question |
| -- and is used to post the error message. |
| |
| function Collect_Primitive_Operations (T : Entity_Id) return Elist_Id; |
| -- Called upon type derivation and extension. We scan the declarative |
| -- part in which the type appears, and collect subprograms that have |
| -- one subsidiary subtype of the type. These subprograms can only |
| -- appear after the type itself. |
| |
| function Compile_Time_Constraint_Error |
| (N : Node_Id; |
| Msg : String; |
| Ent : Entity_Id := Empty; |
| Loc : Source_Ptr := No_Location; |
| Warn : Boolean := False) return Node_Id; |
| -- This is similar to Apply_Compile_Time_Constraint_Error in that it |
| -- generates a warning (or error) message in the same manner, but it does |
| -- not replace any nodes. For convenience, the function always returns its |
| -- first argument. The message is a warning if the message ends with ?, or |
| -- we are operating in Ada 83 mode, or if the Warn parameter is set to |
| -- True. |
| |
| procedure Conditional_Delay (New_Ent, Old_Ent : Entity_Id); |
| -- Sets the Has_Delayed_Freeze flag of New if the Delayed_Freeze flag |
| -- of Old is set and Old has no yet been Frozen (i.e. Is_Frozen is false); |
| |
| function Current_Entity (N : Node_Id) return Entity_Id; |
| -- Find the currently visible definition for a given identifier, that is to |
| -- say the first entry in the visibility chain for the Chars of N. |
| |
| function Current_Entity_In_Scope (N : Node_Id) return Entity_Id; |
| -- Find whether there is a previous definition for identifier N in the |
| -- current scope. Because declarations for a scope are not necessarily |
| -- contiguous (e.g. for packages) the first entry on the visibility chain |
| -- for N is not necessarily in the current scope. |
| |
| function Current_Scope return Entity_Id; |
| -- Get entity representing current scope |
| |
| function Current_Subprogram return Entity_Id; |
| -- Returns current enclosing subprogram. If Current_Scope is a subprogram, |
| -- then that is what is returned, otherwise the Enclosing_Subprogram of |
| -- the Current_Scope is returned. The returned value is Empty if this |
| -- is called from a library package which is not within any subprogram. |
| |
| function Defining_Entity (N : Node_Id) return Entity_Id; |
| -- Given a declaration N, returns the associated defining entity. If |
| -- the declaration has a specification, the entity is obtained from |
| -- the specification. If the declaration has a defining unit name, |
| -- then the defining entity is obtained from the defining unit name |
| -- ignoring any child unit prefixes. |
| |
| function Denotes_Discriminant |
| (N : Node_Id; |
| Check_Protected : Boolean := False) return Boolean; |
| -- Returns True if node N is an Entity_Name node for a discriminant. |
| -- If the flag Check_Protected is true, function also returns true |
| -- when N denotes the discriminal of the discriminant of a protected |
| -- type. This is necessary to disable some optimizations on private |
| -- components of protected types. |
| |
| function Depends_On_Discriminant (N : Node_Id) return Boolean; |
| -- Returns True if N denotes a discriminant or if N is a range, a subtype |
| -- indication or a scalar subtype where one of the bounds is a |
| -- discriminant. |
| |
| function Designate_Same_Unit |
| (Name1 : Node_Id; |
| Name2 : Node_Id) return Boolean; |
| -- Return true if Name1 and Name2 designate the same unit name; |
| -- each of these names is supposed to be a selected component name, |
| -- an expanded name, a defining program unit name or an identifier |
| |
| function Enclosing_Generic_Body |
| (N : Node_Id) return Node_Id; |
| -- Returns the Node_Id associated with the innermost enclosing |
| -- generic body, if any. If none, then returns Empty. |
| |
| function Enclosing_Generic_Unit |
| (N : Node_Id) return Node_Id; |
| -- Returns the Node_Id associated with the innermost enclosing |
| -- generic unit, if any. If none, then returns Empty. |
| |
| function Enclosing_Lib_Unit_Entity return Entity_Id; |
| -- Returns the entity of enclosing N_Compilation_Unit Node which is the |
| -- root of the current scope (which must not be Standard_Standard, and |
| -- the caller is responsible for ensuring this condition). |
| |
| function Enclosing_Lib_Unit_Node (N : Node_Id) return Node_Id; |
| -- Returns the enclosing N_Compilation_Unit Node that is the root |
| -- of a subtree containing N. |
| |
| function Enclosing_Subprogram (E : Entity_Id) return Entity_Id; |
| -- Utility function to return the Ada entity of the subprogram enclosing |
| -- the entity E, if any. Returns Empty if no enclosing subprogram. |
| |
| procedure Ensure_Freeze_Node (E : Entity_Id); |
| -- Make sure a freeze node is allocated for entity E. If necessary, |
| -- build and initialize a new freeze node and set Has_Delayed_Freeze |
| -- true for entity E. |
| |
| procedure Enter_Name (Def_Id : Entity_Id); |
| -- Insert new name in symbol table of current scope with check for |
| -- duplications (error message is issued if a conflict is found) |
| -- Note: Enter_Name is not used for overloadable entities, instead |
| -- these are entered using Sem_Ch6.Enter_Overloadable_Entity. |
| |
| procedure Explain_Limited_Type (T : Entity_Id; N : Node_Id); |
| -- This procedure is called after issuing a message complaining |
| -- about an inappropriate use of limited type T. If useful, it |
| -- adds additional continuation lines to the message explaining |
| -- why type T is limited. Messages are placed at node N. |
| |
| function Find_Corresponding_Discriminant |
| (Id : Node_Id; |
| Typ : Entity_Id) return Entity_Id; |
| -- Because discriminants may have different names in a generic unit |
| -- and in an instance, they are resolved positionally when possible. |
| -- A reference to a discriminant carries the discriminant that it |
| -- denotes when analyzed. Subsequent uses of this id on a different |
| -- type denote the discriminant at the same position in this new type. |
| |
| function First_Actual (Node : Node_Id) return Node_Id; |
| -- Node is an N_Function_Call or N_Procedure_Call_Statement node. The |
| -- result returned is the first actual parameter in declaration order |
| -- (not the order of parameters as they appeared in the source, which |
| -- can be quite different as a result of the use of named parameters). |
| -- Empty is returned for a call with no parameters. The procedure for |
| -- iterating through the actuals in declaration order is to use this |
| -- function to find the first actual, and then use Next_Actual to obtain |
| -- the next actual in declaration order. Note that the value returned |
| -- is always the expression (not the N_Parameter_Association nodes |
| -- even if named association is used). |
| |
| function Full_Qualified_Name (E : Entity_Id) return String_Id; |
| -- Generates the string literal corresponding to the E's full qualified |
| -- name in upper case. An ASCII.NUL is appended as the last character. |
| -- The names in the string are generated by Namet.Get_Decoded_Name_String. |
| |
| function Find_Static_Alternative (N : Node_Id) return Node_Id; |
| -- N is a case statement whose expression is a compile-time value. |
| -- Determine the alternative chosen, so that the code of non-selected |
| -- alternatives, and the warnings that may apply to them, are removed. |
| |
| procedure Gather_Components |
| (Typ : Entity_Id; |
| Comp_List : Node_Id; |
| Governed_By : List_Id; |
| Into : Elist_Id; |
| Report_Errors : out Boolean); |
| -- The purpose of this procedure is to gather the valid components in a |
| -- record type according to the values of its discriminants, in order to |
| -- validate the components of a record aggregate. |
| -- |
| -- Typ is the type of the aggregate when its constrained discriminants |
| -- need to be collected, otherwise it is Empty. |
| -- |
| -- Comp_List is an N_Component_List node. |
| -- |
| -- Governed_By is a list of N_Component_Association nodes, where each |
| -- choice list contains the name of a discriminant and the expression |
| -- field gives its value. The values of the discriminants governing |
| -- the (possibly nested) variant parts in Comp_List are found in this |
| -- Component_Association List. |
| -- |
| -- Into is the list where the valid components are appended. Note that |
| -- Into need not be an Empty list. If it's not, components are attached |
| -- to its tail. |
| -- |
| -- Report_Errors is set to True if the values of the discriminants are |
| -- non-static. |
| -- |
| -- This procedure is also used when building a record subtype. If the |
| -- discriminant constraint of the subtype is static, the components of the |
| -- subtype are only those of the variants selected by the values of the |
| -- discriminants. Otherwise all components of the parent must be included |
| -- in the subtype for semantic analysis. |
| |
| function Get_Actual_Subtype (N : Node_Id) return Entity_Id; |
| -- Given a node for an expression, obtain the actual subtype of the |
| -- expression. In the case of a parameter where the formal is an |
| -- unconstrained array or discriminated type, this will be the |
| -- previously constructed subtype of the actual. Note that this is |
| -- not quite the "Actual Subtype" of the RM, since it is always |
| -- a constrained type, i.e. it is the subtype of the value of the |
| -- actual. The actual subtype is also returned in other cases where |
| -- it has already been constructed for an object. Otherwise the |
| -- expression type is returned unchanged, except for the case of an |
| -- unconstrained array type, where an actual subtype is created, using |
| -- Insert_Actions if necessary to insert any associated actions. |
| |
| function Get_Actual_Subtype_If_Available (N : Node_Id) return Entity_Id; |
| -- This is like Get_Actual_Subtype, except that it never constructs an |
| -- actual subtype. If an actual subtype is already available, i.e. the |
| -- Actual_Subtype field of the corresponding entity is set, then it is |
| -- returned. Otherwise the Etype of the node is returned. |
| |
| function Get_Default_External_Name (E : Node_Or_Entity_Id) return Node_Id; |
| -- This is used to construct the string literal node representing a |
| -- default external name, i.e. one that is constructed from the name |
| -- of an entity, or (in the case of extended DEC import/export pragmas, |
| -- an identifier provided as the external name. Letters in the name are |
| -- according to the setting of Opt.External_Name_Default_Casing. |
| |
| function Get_Generic_Entity (N : Node_Id) return Entity_Id; |
| -- Returns the true generic entity in an instantiation. If the name in |
| -- the instantiation is a renaming, the function returns the renamed |
| -- generic. |
| |
| procedure Get_Index_Bounds (N : Node_Id; L, H : out Node_Id); |
| -- This procedure assigns to L and H respectively the values of the |
| -- low and high bounds of node N, which must be a range, subtype |
| -- indication, or the name of a scalar subtype. The result in L, H |
| -- may be set to Error if there was an earlier error in the range. |
| |
| function Get_Enum_Lit_From_Pos |
| (T : Entity_Id; |
| Pos : Uint; |
| Loc : Source_Ptr) return Entity_Id; |
| -- This function obtains the E_Enumeration_Literal entity for the |
| -- specified value from the enumneration type or subtype T. The |
| -- second argument is the Pos value, which is assumed to be in range. |
| -- The third argument supplies a source location for constructed |
| -- nodes returned by this function. |
| |
| procedure Get_Library_Unit_Name_String (Decl_Node : Node_Id); |
| -- Retrieve the fully expanded name of the library unit declared by |
| -- Decl_Node into the name buffer. |
| |
| function Get_Name_Entity_Id (Id : Name_Id) return Entity_Id; |
| -- An entity value is associated with each name in the name table. The |
| -- Get_Name_Entity_Id function fetches the Entity_Id of this entity, |
| -- which is the innermost visible entity with the given name. See the |
| -- body of Sem_Ch8 for further details on handling of entity visibility. |
| |
| function Get_Referenced_Object (N : Node_Id) return Node_Id; |
| -- Given a node, return the renamed object if the node represents |
| -- a renamed object, otherwise return the node unchanged. The node |
| -- may represent an arbitrary expression. |
| |
| function Get_Subprogram_Body (E : Entity_Id) return Node_Id; |
| -- Given the entity for a subprogram (E_Function or E_Procedure), |
| -- return the corresponding N_Subprogram_Body node. If the corresponding |
| -- body of the declaration is missing (as for an imported subprogram) |
| -- return Empty. |
| |
| function Get_Task_Body_Procedure (E : Entity_Id) return Node_Id; |
| pragma Inline (Get_Task_Body_Procedure); |
| -- Given an entity for a task type or subtype, retrieves the |
| -- Task_Body_Procedure field from the corresponding task type |
| -- declaration. |
| |
| function Has_Access_Values (T : Entity_Id) return Boolean; |
| -- Returns true if type or subtype T is an access type, or has a |
| -- component (at any recursive level) that is an access type. This |
| -- is a conservative predicate, if it is not known whether or not |
| -- T contains access values (happens for generic formals in some |
| -- cases), then False is returned. |
| |
| function Has_Declarations (N : Node_Id) return Boolean; |
| -- Determines if the node can have declarations |
| |
| function Has_Discriminant_Dependent_Constraint |
| (Comp : Entity_Id) return Boolean; |
| -- Returns True if and only if Comp has a constrained subtype |
| -- that depends on a discriminant. |
| |
| function Has_Infinities (E : Entity_Id) return Boolean; |
| -- Determines if the range of the floating-point type E includes |
| -- infinities. Returns False if E is not a floating-point type. |
| |
| function Has_Private_Component (Type_Id : Entity_Id) return Boolean; |
| -- Check if a type has a (sub)component of a private type that has not |
| -- yet received a full declaration. |
| |
| function Has_Stream (T : Entity_Id) return Boolean; |
| -- Tests if type T is derived from Ada.Streams.Root_Stream_Type, or |
| -- in the case of a composite type, has a component for which this |
| -- predicate is True, and if so returns True. Otherwise a result of |
| -- False means that there is no Stream type in sight. For a private |
| -- type, the test is applied to the underlying type (or returns False |
| -- if there is no underlying type). |
| |
| function Has_Tagged_Component (Typ : Entity_Id) return Boolean; |
| -- Typ must be a composite type (array or record). This function is used |
| -- to check if '=' has to be expanded into a bunch component comparaisons. |
| |
| function In_Instance return Boolean; |
| -- Returns True if the current scope is within a generic instance |
| |
| function In_Instance_Body return Boolean; |
| -- Returns True if current scope is within the body of an instance, where |
| -- several semantic checks (e.g. accessibility checks) are relaxed. |
| |
| function In_Instance_Not_Visible return Boolean; |
| -- Returns True if current scope is with the private part or the body of |
| -- an instance. Other semantic checks are suppressed in this context. |
| |
| function In_Instance_Visible_Part return Boolean; |
| -- Returns True if current scope is within the visible part of a package |
| -- instance, where several additional semantic checks apply. |
| |
| function In_Package_Body return Boolean; |
| -- Returns True if current scope is within a package body |
| |
| function In_Subprogram_Or_Concurrent_Unit return Boolean; |
| -- Determines if the current scope is within a subprogram compilation |
| -- unit (inside a subprogram declaration, subprogram body, or generic |
| -- subprogram declaration) or within a task or protected body. The test |
| -- is for appearing anywhere within such a construct (that is it does not |
| -- need to be directly within). |
| |
| function In_Visible_Part (Scope_Id : Entity_Id) return Boolean; |
| -- Determine whether a declaration occurs within the visible part of a |
| -- package specification. The package must be on the scope stack, and the |
| -- corresponding private part must not. |
| |
| procedure Insert_Explicit_Dereference (N : Node_Id); |
| -- In a context that requires a composite or subprogram type and |
| -- where a prefix is an access type, rewrite the access type node |
| -- N (which is the prefix, e.g. of an indexed component) as an |
| -- explicit dereference. |
| |
| function Is_AAMP_Float (E : Entity_Id) return Boolean; |
| -- Defined for all type entities. Returns True only for the base type |
| -- of float types with AAMP format. The particular format is determined |
| -- by the Digits_Value value which is 6 for the 32-bit floating point type, |
| -- or 9 for the 48-bit type. This is not an attribute function (like |
| -- VAX_Float) in order to not use up an extra flag and to prevent |
| -- the dependency of Einfo on Targparm which would be required for a |
| -- synthesized attribute. |
| |
| function Is_Actual_Parameter (N : Node_Id) return Boolean; |
| -- Determines if N is an actual parameter in a subprogram call |
| |
| function Is_Aliased_View (Obj : Node_Id) return Boolean; |
| -- Determine if Obj is an aliased view, i.e. the name of an |
| -- object to which 'Access or 'Unchecked_Access can apply. |
| |
| function Is_Ancestor_Package |
| (E1 : Entity_Id; |
| E2 : Entity_Id) return Boolean; |
| -- Determine whether package E1 is an ancestor of E2 |
| |
| function Is_Atomic_Object (N : Node_Id) return Boolean; |
| -- Determines if the given node denotes an atomic object in the sense |
| -- of the legality checks described in RM C.6(12). |
| |
| function Is_Controlling_Limited_Procedure |
| (Proc_Nam : Entity_Id) return Boolean; |
| -- Ada 2005 (AI-345): Determine whether Proc_Nam is a primitive procedure |
| -- of a limited interface with a controlling first parameter. |
| |
| function Is_Dependent_Component_Of_Mutable_Object |
| (Object : Node_Id) return Boolean; |
| -- Returns True if Object is the name of a subcomponent that |
| -- depends on discriminants of a variable whose nominal subtype |
| -- is unconstrained and not indefinite, and the variable is |
| -- not aliased. Otherwise returns False. The nodes passed |
| -- to this function are assumed to denote objects. |
| |
| function Is_Dereferenced (N : Node_Id) return Boolean; |
| -- N is a subexpression node of an access type. This function returns |
| -- true if N appears as the prefix of a node that does a dereference |
| -- of the access value (selected/indexed component, explicit dereference |
| -- or a slice), and false otherwise. |
| |
| function Is_Descendent_Of (T1 : Entity_Id; T2 : Entity_Id) return Boolean; |
| -- Returns True if type T1 is a descendent of type T2, and false otherwise. |
| -- This is the RM definition, a type is a descendent of another type if it |
| -- is the same type or is derived from a descendent of the other type. |
| |
| function Is_Descendent_Of_Address (T1 : Entity_Id) return Boolean; |
| -- Returns True if type T1 is a descendent of Address or its base type. |
| -- Similar to calling Is_Descendent_Of with Base_Type (RTE (RE_Address)) |
| -- except that it avoids creating an unconditional dependency on System. |
| |
| function Is_False (U : Uint) return Boolean; |
| -- The argument is a Uint value which is the Boolean'Pos value of a |
| -- Boolean operand (i.e. is either 0 for False, or 1 for True). This |
| -- function simply tests if it is False (i.e. zero) |
| |
| function Is_Fixed_Model_Number (U : Ureal; T : Entity_Id) return Boolean; |
| -- Returns True iff the number U is a model number of the fixed- |
| -- point type T, i.e. if it is an exact multiple of Small. |
| |
| function Is_Fully_Initialized_Type (Typ : Entity_Id) return Boolean; |
| -- Typ is a type entity. This function returns true if this type is |
| -- fully initialized, meaning that an object of the type is fully |
| -- initialized. Note that initialization resulting from the use of |
| -- pragma Normalized_Scalars does not count. Note that this is only |
| -- used for the purpose of issuing warnings for objects that are |
| -- potentially referenced uninitialized. This means that the result |
| -- returned is not crucial, but probably should err on the side of |
| -- thinking things are fully initialized if it does not know. |
| |
| function Is_Inherited_Operation (E : Entity_Id) return Boolean; |
| -- E is a subprogram. Return True is E is an implicit operation inherited |
| -- by a derived type declarations. |
| |
| function Is_Lvalue (N : Node_Id) return Boolean; |
| -- Determines if N could be an lvalue (e.g. an assignment left hand side). |
| -- This determination is conservative, it must never answer False if N is |
| -- an lvalue, but it can answer True when N is not an lvalue. An lvalue is |
| -- defined as any expression which appears in a context where a name is |
| -- required by the syntax, and the identity, rather than merely the value |
| -- of the node is needed (for example, the prefix of an Access attribute |
| -- is in this category). |
| |
| function Is_Library_Level_Entity (E : Entity_Id) return Boolean; |
| -- A library-level declaration is one that is accessible from Standard, |
| -- i.e. a library unit or an entity declared in a library package. |
| |
| function Is_Local_Variable_Reference (Expr : Node_Id) return Boolean; |
| -- Determines whether Expr is a refeference to a variable or IN OUT |
| -- mode parameter of the current enclosing subprogram. |
| -- Why are OUT parameters not considered here ??? |
| |
| function Is_Object_Reference (N : Node_Id) return Boolean; |
| -- Determines if the tree referenced by N represents an object. Both |
| -- variable and constant objects return True (compare Is_Variable). |
| |
| function Is_OK_Variable_For_Out_Formal (AV : Node_Id) return Boolean; |
| -- Used to test if AV is an acceptable formal for an OUT or IN OUT |
| -- formal. Note that the Is_Variable function is not quite the right |
| -- test because this is a case in which conversions whose expression |
| -- is a variable (in the Is_Variable sense) with a non-tagged type |
| -- target are considered view conversions and hence variables. |
| |
| function Is_Partially_Initialized_Type (Typ : Entity_Id) return Boolean; |
| -- Typ is a type entity. This function returns true if this type is |
| -- partly initialized, meaning that an object of the type is at least |
| -- partly initialized (in particular in the record case, that at least |
| -- one field has an initialization expression). Note that initialization |
| -- resulting from the use of pragma Normalized_Scalars does not count. |
| |
| function Is_Potentially_Persistent_Type (T : Entity_Id) return Boolean; |
| -- Determines if type T is a potentially persistent type. A potentially |
| -- persistent type is defined (recursively) as a scalar type, a non-tagged |
| -- record whose components are all of a potentially persistent type, or an |
| -- array with all static constraints whose component type is potentially |
| -- persistent. A private type is potentially persistent if the full type |
| -- is potentially persistent. |
| |
| function Is_RCI_Pkg_Spec_Or_Body (Cunit : Node_Id) return Boolean; |
| -- Return True if a compilation unit is the specification or the |
| -- body of a remote call interface package. |
| |
| function Is_Remote_Access_To_Class_Wide_Type (E : Entity_Id) return Boolean; |
| -- Return True if E is a remote access-to-class-wide-limited_private type |
| |
| function Is_Remote_Access_To_Subprogram_Type (E : Entity_Id) return Boolean; |
| -- Return True if E is a remote access to subprogram type |
| |
| function Is_Remote_Call (N : Node_Id) return Boolean; |
| -- Return True if N denotes a potentially remote call |
| |
| function Is_Renamed_Entry (Proc_Nam : Entity_Id) return Boolean; |
| -- Return True if Proc_Nam is a procedure renaming of an entry |
| |
| function Is_Selector_Name (N : Node_Id) return Boolean; |
| -- Given an N_Identifier node N, determines if it is a Selector_Name. |
| -- As described in Sinfo, Selector_Names are special because they |
| -- represent use of the N_Identifier node for a true identifer, when |
| -- normally such nodes represent a direct name. |
| |
| function Is_Statement (N : Node_Id) return Boolean; |
| -- Check if the node N is a statement node. Note that this includes |
| -- the case of procedure call statements (unlike the direct use of |
| -- the N_Statement_Other_Than_Procedure_Call subtype from Sinfo). |
| -- Note that a label is *not* a statement, and will return False. |
| |
| function Is_Transfer (N : Node_Id) return Boolean; |
| -- Returns True if the node N is a statement which is known to cause |
| -- an unconditional transfer of control at runtime, i.e. the following |
| -- statement definitely will not be executed. |
| |
| function Is_True (U : Uint) return Boolean; |
| -- The argument is a Uint value which is the Boolean'Pos value of a |
| -- Boolean operand (i.e. is either 0 for False, or 1 for True). This |
| -- function simply tests if it is True (i.e. non-zero) |
| |
| function Is_Variable (N : Node_Id) return Boolean; |
| -- Determines if the tree referenced by N represents a variable, i.e. |
| -- can appear on the left side of an assignment. There is one situation, |
| -- namely formal parameters, in which non-tagged type conversions are |
| -- also considered variables, but Is_Variable returns False for such |
| -- cases, since it has no knowledge of the context. Note that this is |
| -- the point at which Assignment_OK is checked, and True is returned |
| -- for any tree thus marked. |
| |
| function Is_Volatile_Object (N : Node_Id) return Boolean; |
| -- Determines if the given node denotes an volatile object in the sense |
| -- of the legality checks described in RM C.6(12). Note that the test |
| -- here is for something actually declared as volatile, not for an object |
| -- that gets treated as volatile (see Einfo.Treat_As_Volatile). |
| |
| procedure Kill_Current_Values; |
| -- This procedure is called to clear all constant indications from all |
| -- entities in the current scope and in any parent scopes if the current |
| -- scope is a block or a pacakage (and that recursion continues to the |
| -- top scope that is not a block or a package). This is used when the |
| -- sequential flow-of-control assumption is violated (occurence of a |
| -- label, head of a loop, or start of an exception handler). The effect |
| -- of the call is to clear the Constant_Value field (but we do not need |
| -- to clear the Is_True_Constant flag, since that only gets reset if |
| -- there really is an assignment somewhere in the entity scope). This |
| -- procedure also calls Kill_All_Checks, since this is a special case |
| -- of needing to forget saved values. This procedure also clears any |
| -- Is_Known_Non_Null flags in variables, constants or parameters |
| -- since these are also not known to be valid. |
| |
| procedure Kill_Current_Values (Ent : Entity_Id); |
| -- This performs the same processing as described above for the form with |
| -- no argument, but for the specific entity given. The call has no effect |
| -- if the entity Ent is not for an object. |
| |
| procedure Kill_Size_Check_Code (E : Entity_Id); |
| -- Called when an address clause or pragma Import is applied to an |
| -- entity. If the entity is a variable or a constant, and size check |
| -- code is present, this size check code is killed, since the object |
| -- will not be allocated by the program. |
| |
| function New_External_Entity |
| (Kind : Entity_Kind; |
| Scope_Id : Entity_Id; |
| Sloc_Value : Source_Ptr; |
| Related_Id : Entity_Id; |
| Suffix : Character; |
| Suffix_Index : Nat := 0; |
| Prefix : Character := ' ') return Entity_Id; |
| -- This function creates an N_Defining_Identifier node for an internal |
| -- created entity, such as an implicit type or subtype, or a record |
| -- initialization procedure. The entity name is constructed with a call |
| -- to New_External_Name (Related_Id, Suffix, Suffix_Index, Prefix), so |
| -- that the generated name may be referenced as a public entry, and the |
| -- Is_Public flag is set if needed (using Set_Public_Status). If the |
| -- entity is for a type or subtype, the size/align fields are initialized |
| -- to unknown (Uint_0). |
| |
| function New_Internal_Entity |
| (Kind : Entity_Kind; |
| Scope_Id : Entity_Id; |
| Sloc_Value : Source_Ptr; |
| Id_Char : Character) return Entity_Id; |
| -- This function is similar to New_External_Entity, except that the |
| -- name is constructed by New_Internal_Name (Id_Char). This is used |
| -- when the resulting entity does not have to be referenced as a |
| -- public entity (and in this case Is_Public is not set). |
| |
| procedure Next_Actual (Actual_Id : in out Node_Id); |
| pragma Inline (Next_Actual); |
| -- Next_Actual (N) is equivalent to N := Next_Actual (N) |
| |
| function Next_Actual (Actual_Id : Node_Id) return Node_Id; |
| -- Find next actual parameter in declaration order. As described for |
| -- First_Actual, this is the next actual in the declaration order, not |
| -- the call order, so this does not correspond to simply taking the |
| -- next entry of the Parameter_Associations list. The argument is an |
| -- actual previously returned by a call to First_Actual or Next_Actual. |
| -- Note that the result produced is always an expression, not a parameter |
| -- assciation node, even if named notation was used. |
| |
| procedure Normalize_Actuals |
| (N : Node_Id; |
| S : Entity_Id; |
| Report : Boolean; |
| Success : out Boolean); |
| -- Reorders lists of actuals according to names of formals, value returned |
| -- in Success indicates sucess of reordering. For more details, see body. |
| -- Errors are reported only if Report is set to True. |
| |
| procedure Note_Possible_Modification (N : Node_Id); |
| -- This routine is called if the sub-expression N maybe the target of |
| -- an assignment (e.g. it is the left side of an assignment, used as |
| -- an out parameters, or used as prefixes of access attributes). It |
| -- sets May_Be_Modified in the associated entity if there is one, |
| -- taking into account the rule that in the case of renamed objects, |
| -- it is the flag in the renamed object that must be set. |
| |
| function Object_Access_Level (Obj : Node_Id) return Uint; |
| -- Return the accessibility level of the view of the object Obj. |
| -- For convenience, qualified expressions applied to object names |
| -- are also allowed as actuals for this function. |
| |
| function Private_Component (Type_Id : Entity_Id) return Entity_Id; |
| -- Returns some private component (if any) of the given Type_Id. |
| -- Used to enforce the rules on visibility of operations on composite |
| -- types, that depend on the full view of the component type. For a |
| -- record type there may be several such components, we just return |
| -- the first one. |
| |
| procedure Process_End_Label |
| (N : Node_Id; |
| Typ : Character; |
| Ent : Entity_Id); |
| -- N is a node whose End_Label is to be processed, generating all |
| -- appropriate cross-reference entries, and performing style checks |
| -- for any identifier references in the end label. Typ is either |
| -- 'e' or 't indicating the type of the cross-reference entity |
| -- (e for spec, t for body, see Lib.Xref spec for details). The |
| -- parameter Ent gives the entity to which the End_Label refers, |
| -- and to which cross-references are to be generated. |
| |
| function Real_Convert (S : String) return Node_Id; |
| -- S is a possibly signed syntactically valid real literal. The result |
| -- returned is an N_Real_Literal node representing the literal value. |
| |
| function Rep_To_Pos_Flag (E : Entity_Id; Loc : Source_Ptr) return Node_Id; |
| -- This is used to construct the second argument in a call to Rep_To_Pos |
| -- which is Standard_True if range checks are enabled (E is an entity to |
| -- which the Range_Checks_Suppressed test is applied), and Standard_False |
| -- if range checks are suppressed. Loc is the location for the node that |
| -- is returned (which is a New_Occurrence of the appropriate entity). |
| -- |
| -- Note: one might think that it would be fine to always use True and |
| -- to ignore the suppress in this case, but it is generally better to |
| -- believe a request to suppress exceptions if possible, and further |
| -- more there is at least one case in the generated code (the code for |
| -- array assignment in a loop) that depends on this suppression. |
| |
| procedure Require_Entity (N : Node_Id); |
| -- N is a node which should have an entity value if it is an entity name. |
| -- If not, then check if there were previous errors. If so, just fill |
| -- in with Any_Id and ignore. Otherwise signal a program error exception. |
| -- This is used as a defense mechanism against ill-formed trees caused by |
| -- previous errors (particularly in -gnatq mode). |
| |
| function Requires_Transient_Scope (Id : Entity_Id) return Boolean; |
| -- E is a type entity. The result is True when temporaries of this |
| -- type need to be wrapped in a transient scope to be reclaimed |
| -- properly when a secondary stack is in use. Examples of types |
| -- requiring such wrapping are controlled types and variable-sized |
| -- types including unconstrained arrays |
| |
| procedure Reset_Analyzed_Flags (N : Node_Id); |
| -- Reset the Analyzed flags in all nodes of the tree whose root is N |
| |
| function Safe_To_Capture_Value |
| (N : Node_Id; |
| Ent : Entity_Id) return Boolean; |
| -- The caller is interested in capturing a value (either the current |
| -- value, or an indication that the value is non-null) for the given |
| -- entity Ent. This value can only be captured if sequential execution |
| -- semantics can be properly guaranteed so that a subsequent reference |
| -- will indeed be sure that this current value indication is correct. |
| -- The node N is the construct which resulted in the possible capture |
| -- of the value (this is used to check if we are in a conditional). |
| |
| function Same_Name (N1, N2 : Node_Id) return Boolean; |
| -- Determine if two (possibly expanded) names are the same name |
| |
| function Same_Type (T1, T2 : Entity_Id) return Boolean; |
| -- Determines if T1 and T2 represent exactly the same type. Two types |
| -- are the same if they are identical, or if one is an unconstrained |
| -- subtype of the other, or they are both common subtypes of the same |
| -- type with identical constraints. The result returned is conservative. |
| -- It is True if the types are known to be the same, but a result of |
| -- False is indecisive (e.g. the compiler may not be able to tell that |
| -- two constraints are identical). |
| |
| function Scope_Within_Or_Same (Scope1, Scope2 : Entity_Id) return Boolean; |
| -- Determines if the entity Scope1 is the same as Scope2, or if it is |
| -- inside it, where both entities represent scopes. Note that scopes |
| -- are only partially ordered, so Scope_Within_Or_Same (A,B) and |
| -- Scope_Within_Or_Same (B,A) can both be False for a given pair A,B. |
| |
| function Scope_Within (Scope1, Scope2 : Entity_Id) return Boolean; |
| -- Like Scope_Within_Or_Same, except that this function returns |
| -- False in the case where Scope1 and Scope2 are the same scope. |
| |
| procedure Set_Current_Entity (E : Entity_Id); |
| -- Establish the entity E as the currently visible definition of its |
| -- associated name (i.e. the Node_Id associated with its name) |
| |
| procedure Set_Entity_With_Style_Check (N : Node_Id; Val : Entity_Id); |
| -- This procedure has the same calling sequence as Set_Entity, but |
| -- if Style_Check is set, then it calls a style checking routine which |
| -- can check identifier spelling style. |
| |
| procedure Set_Name_Entity_Id (Id : Name_Id; Val : Entity_Id); |
| -- Sets the Entity_Id value associated with the given name, which is the |
| -- Id of the innermost visible entity with the given name. See the body |
| -- of package Sem_Ch8 for further details on the handling of visibility. |
| |
| procedure Set_Next_Actual (Ass1_Id : Node_Id; Ass2_Id : Node_Id); |
| -- The arguments may be parameter associations, whose descendants |
| -- are the optional formal name and the actual parameter. Positional |
| -- parameters are already members of a list, and do not need to be |
| -- chained separately. See also First_Actual and Next_Actual. |
| |
| procedure Set_Public_Status (Id : Entity_Id); |
| -- If an entity (visible or otherwise) is defined in a library |
| -- package, or a package that is itself public, then this subprogram |
| -- labels the entity public as well. |
| |
| procedure Set_Scope_Is_Transient (V : Boolean := True); |
| -- Set the flag Is_Transient of the current scope |
| |
| procedure Set_Size_Info (T1, T2 : Entity_Id); |
| -- Copies the Esize field and Has_Biased_Representation flag from sub(type) |
| -- entity T2 to (sub)type entity T1. Also copies the Is_Unsigned_Type flag |
| -- in the fixed-point and discrete cases, and also copies the alignment |
| -- value from T2 to T1. It does NOT copy the RM_Size field, which must be |
| -- separately set if this is required to be copied also. |
| |
| function Scope_Is_Transient return Boolean; |
| -- True if the current scope is transient |
| |
| function Static_Integer (N : Node_Id) return Uint; |
| -- This function analyzes the given expression node and then resolves it |
| -- as any integer type. If the result is static, then the value of the |
| -- universal expression is returned, otherwise an error message is output |
| -- and a value of No_Uint is returned. |
| |
| function Statically_Different (E1, E2 : Node_Id) return Boolean; |
| -- Return True if it can be statically determined that the Expressions |
| -- E1 and E2 refer to different objects |
| |
| function Subprogram_Access_Level (Subp : Entity_Id) return Uint; |
| -- Return the accessibility level of the view denoted by Subp |
| |
| procedure Trace_Scope (N : Node_Id; E : Entity_Id; Msg : String); |
| -- Print debugging information on entry to each unit being analyzed |
| |
| procedure Transfer_Entities (From : Entity_Id; To : Entity_Id); |
| -- Move a list of entities from one scope to another, and recompute |
| -- Is_Public based upon the new scope. |
| |
| function Type_Access_Level (Typ : Entity_Id) return Uint; |
| -- Return the accessibility level of Typ |
| |
| function Unit_Declaration_Node (Unit_Id : Entity_Id) return Node_Id; |
| -- Unit_Id is the simple name of a program unit, this function returns the |
| -- corresponding xxx_Declaration node for the entity. Also applies to the |
| -- body entities for subprograms, tasks and protected units, in which case |
| -- it returns the subprogram, task or protected body node for it. The unit |
| -- may be a child unit with any number of ancestors. |
| |
| function Universal_Interpretation (Opnd : Node_Id) return Entity_Id; |
| -- Yields universal_Integer or Universal_Real if this is a candidate |
| |
| function Within_Init_Proc return Boolean; |
| -- Determines if Current_Scope is within an init proc |
| |
| procedure Wrong_Type (Expr : Node_Id; Expected_Type : Entity_Id); |
| -- Output error message for incorrectly typed expression. Expr is the |
| -- node for the incorrectly typed construct (Etype (Expr) is the type |
| -- found), and Expected_Type is the entity for the expected type. Note |
| -- that Expr does not have to be a subexpression, anything with an |
| -- Etype field may be used. |
| |
| private |
| pragma Inline (Current_Entity); |
| pragma Inline (Get_Name_Entity_Id); |
| pragma Inline (Is_False); |
| pragma Inline (Is_Statement); |
| pragma Inline (Is_True); |
| pragma Inline (Set_Current_Entity); |
| pragma Inline (Set_Name_Entity_Id); |
| pragma Inline (Set_Size_Info); |
| |
| end Sem_Util; |
