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Diffstat (limited to 'gcc-4.4.3/gcc/ada/sem_type.ads')
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diff --git a/gcc-4.4.3/gcc/ada/sem_type.ads b/gcc-4.4.3/gcc/ada/sem_type.ads deleted file mode 100644 index a4986fc61..000000000 --- a/gcc-4.4.3/gcc/ada/sem_type.ads +++ /dev/null @@ -1,255 +0,0 @@ ------------------------------------------------------------------------------- --- -- --- GNAT COMPILER COMPONENTS -- --- -- --- S E M _ T Y P E -- --- -- --- S p e c -- --- -- --- Copyright (C) 1992-2007, Free Software Foundation, Inc. -- --- -- --- GNAT is free software; you can redistribute it and/or modify it under -- --- terms of the GNU General Public License as published by the Free Soft- -- --- 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. 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 COPYING3. If not, go to -- --- http://www.gnu.org/licenses for a complete copy of the license. -- --- -- --- GNAT was originally developed by the GNAT team at New York University. -- --- Extensive contributions were provided by Ada Core Technologies Inc. -- --- -- ------------------------------------------------------------------------------- - --- This unit contains the routines used to handle type determination, --- including the routine used to support overload resolution. - -with Types; use Types; - -package Sem_Type is - - --------------------------------------------- - -- Data Structures for Overload Resolution -- - --------------------------------------------- - - -- To determine the unique meaning of an identifier, overload resolution - -- may have to be performed if the visibility rules alone identify more - -- than one possible entity as the denotation of a given identifier. When - -- the visibility rules find such a potential ambiguity, the set of - -- possible interpretations must be attached to the identifier, and - -- overload resolution must be performed over the innermost enclosing - -- complete context. At the end of the resolution, either a single - -- interpretation is found for all identifiers in the context, or else a - -- type error (invalid type or ambiguous reference) must be signalled. - - -- The set of interpretations of a given name is stored in a data structure - -- that is separate from the syntax tree, because it corresponds to - -- transient information. The interpretations themselves are stored in - -- table All_Interp. A mapping from tree nodes to sets of interpretations - -- called Interp_Map, is maintained by the overload resolution routines. - -- Both these structures are initialized at the beginning of every complete - -- context. - - -- Corresponding to the set of interpretations for a given overloadable - -- identifier, there is a set of possible types corresponding to the types - -- that the overloaded call may return. We keep a 1-to-1 correspondence - -- between interpretations and types: for user-defined subprograms the - -- type is the declared return type. For operators, the type is determined - -- by the type of the arguments. If the arguments themselves are - -- overloaded, we enter the operator name in the names table for each - -- possible result type. In most cases, arguments are not overloaded and - -- only one interpretation is present anyway. - - type Interp is record - Nam : Entity_Id; - Typ : Entity_Id; - Abstract_Op : Entity_Id := Empty; - end record; - - -- Entity Abstract_Op is set to the abstract operation which potentially - -- disables the interpretation in Ada 2005 mode. - - No_Interp : constant Interp := (Empty, Empty, Empty); - - subtype Interp_Index is Int; - - --------------------- - -- Error Reporting -- - --------------------- - - -- A common error is the use of an operator in infix notation on arguments - -- of a type that is not directly visible. Rather than diagnosing a type - -- mismatch, it is better to indicate that the type can be made use-visible - -- with the appropriate use clause. The global variable Candidate_Type is - -- set in Add_One_Interp whenever an interpretation might be legal for an - -- operator if the type were directly visible. This variable is used in - -- sem_ch4 when no legal interpretation is found. - - Candidate_Type : Entity_Id; - - ----------------- - -- Subprograms -- - ----------------- - - procedure Init_Interp_Tables; - -- Invoked by gnatf when processing multiple files - - procedure Collect_Interps (N : Node_Id); - -- Invoked when the name N has more than one visible interpretation. - -- This is the high level routine which accumulates the possible - -- interpretations of the node. The first meaning and type of N have - -- already been stored in N. If the name is an expanded name, the homonyms - -- are only those that belong to the same scope. - - function Is_Invisible_Operator - (N : Node_Id; - T : Entity_Id) - return Boolean; - -- Check whether a predefined operation with universal operands appears - -- in a context in which the operators of the expected type are not - -- visible. - - procedure List_Interps (Nam : Node_Id; Err : Node_Id); - -- List candidate interpretations of an overloaded name. Used for - -- various error reports. - - procedure Add_One_Interp - (N : Node_Id; - E : Entity_Id; - T : Entity_Id; - Opnd_Type : Entity_Id := Empty); - -- Add (E, T) to the list of interpretations of the node being resolved. - -- For calls and operators, i.e. for nodes that have a name field, - -- E is an overloadable entity, and T is its type. For constructs such - -- as indexed expressions, the caller sets E equal to T, because the - -- overloading comes from other fields, and the node itself has no name - -- to resolve. Hidden denotes whether an interpretation has been disabled - -- by an abstract operator. Add_One_Interp includes semantic processing to - -- deal with adding entries that hide one another etc. - - -- For operators, the legality of the operation depends on the visibility - -- of T and its scope. If the operator is an equality or comparison, T is - -- always Boolean, and we use Opnd_Type, which is a candidate type for one - -- of the operands of N, to check visibility. - - procedure End_Interp_List; - -- End the list of interpretations of current node - - procedure Get_First_Interp - (N : Node_Id; - I : out Interp_Index; - It : out Interp); - -- Initialize iteration over set of interpretations for Node N. The first - -- interpretation is placed in It, and I is initialized for subsequent - -- calls to Get_Next_Interp. - - procedure Get_Next_Interp (I : in out Interp_Index; It : out Interp); - -- Iteration step over set of interpretations. Using the value in I, which - -- was set by a previous call to Get_First_Interp or Get_Next_Interp, the - -- next interpretation is placed in It, and I is updated for the next call. - -- The end of the list of interpretations is signalled by It.Nam = Empty. - - procedure Remove_Interp (I : in out Interp_Index); - -- Remove an interpretation that his hidden by another, or that does not - -- match the context. The value of I on input was set by a call to either - -- Get_First_Interp or Get_Next_Interp and references the interpretation - -- to be removed. The only allowed use of the exit value of I is as input - -- to a subsequent call to Get_Next_Interp, which yields the interpretation - -- following the removed one. - - procedure Save_Interps (Old_N : Node_Id; New_N : Node_Id); - -- If an overloaded node is rewritten during semantic analysis, its - -- possible interpretations must be linked to the copy. This procedure - -- transfers the overload information from Old_N, the old node, to - -- New_N, its new copy. It has no effect in the non-overloaded case. - - function Covers (T1, T2 : Entity_Id) return Boolean; - -- This is the basic type compatibility routine. T1 is the expected - -- type, imposed by context, and T2 is the actual type. The processing - -- reflects both the definition of type coverage and the rules - -- for operand matching. - - function Disambiguate - (N : Node_Id; - I1, I2 : Interp_Index; - Typ : Entity_Id) - return Interp; - -- If more than one interpretation of a name in a call is legal, apply - -- preference rules (universal types first) and operator visibility in - -- order to remove ambiguity. I1 and I2 are the first two interpretations - -- that are compatible with the context, but there may be others. - - function Entity_Matches_Spec (Old_S, New_S : Entity_Id) return Boolean; - -- To resolve subprogram renaming and default formal subprograms in generic - -- definitions. Old_S is a possible interpretation of the entity being - -- renamed, New_S has an explicit signature. If Old_S is a subprogram, as - -- opposed to an operator, type and mode conformance are required. - - function Find_Unique_Type (L : Node_Id; R : Node_Id) return Entity_Id; - -- Used in second pass of resolution, for equality and comparison nodes. - -- L is the left operand, whose type is known to be correct, and R is - -- the right operand, which has one interpretation compatible with that - -- of L. Return the type intersection of the two. - - function Has_Compatible_Type - (N : Node_Id; - Typ : Entity_Id) - return Boolean; - -- Verify that some interpretation of the node N has a type compatible - -- with Typ. If N is not overloaded, then its unique type must be - -- compatible with Typ. Otherwise iterate through the interpretations - -- of N looking for a compatible one. - - function Hides_Op (F : Entity_Id; Op : Entity_Id) return Boolean; - -- A user-defined function hides a predefined operator if it is - -- matches the signature of the operator, and is declared in an - -- open scope, or in the scope of the result type. - - function Interface_Present_In_Ancestor - (Typ : Entity_Id; - Iface : Entity_Id) return Boolean; - -- Ada 2005 (AI-251): Typ must be a tagged record type/subtype and Iface - -- must be an abstract interface type (or a class-wide abstract interface). - -- This function is used to check if Typ or some ancestor of Typ implements - -- Iface (returning True only if so). - - function Intersect_Types (L, R : Node_Id) return Entity_Id; - -- Find the common interpretation to two analyzed nodes. If one of the - -- interpretations is universal, choose the non-universal one. If either - -- node is overloaded, find single common interpretation. - - function Is_Ancestor (T1, T2 : Entity_Id) return Boolean; - -- T1 is a tagged type (not class-wide). Verify that it is one of the - -- ancestors of type T2 (which may or not be class-wide) - - function Is_Subtype_Of (T1 : Entity_Id; T2 : Entity_Id) return Boolean; - -- Checks whether T1 is any subtype of T2 directly or indirectly. Applies - -- only to scalar subtypes ??? - - function Operator_Matches_Spec (Op, New_S : Entity_Id) return Boolean; - -- Used to resolve subprograms renaming operators, and calls to user - -- defined operators. Determines whether a given operator Op, matches - -- a specification, New_S. - - procedure Set_Abstract_Op (I : Interp_Index; V : Entity_Id); - -- Set the abstract operation field of an interpretation - - function Valid_Comparison_Arg (T : Entity_Id) return Boolean; - -- A valid argument to an ordering operator must be a discrete type, a - -- real type, or a one dimensional array with a discrete component type. - - function Valid_Boolean_Arg (T : Entity_Id) return Boolean; - -- A valid argument of a boolean operator is either some boolean type, - -- or a one-dimensional array of boolean type. - - procedure Write_Interp_Ref (Map_Ptr : Int); - -- Debugging procedure to display entry in Interp_Map. Would not be - -- needed if it were possible to debug instantiations of Table. - - procedure Write_Overloads (N : Node_Id); - -- Debugging procedure to output info on possibly overloaded entities - -- for specified node. - -end Sem_Type; |