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Diffstat (limited to 'gcc-4.4.3/gcc/ada/sem_case.ads')
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diff --git a/gcc-4.4.3/gcc/ada/sem_case.ads b/gcc-4.4.3/gcc/ada/sem_case.ads new file mode 100644 index 000000000..dcc729315 --- /dev/null +++ b/gcc-4.4.3/gcc/ada/sem_case.ads @@ -0,0 +1,121 @@ +------------------------------------------------------------------------------ +-- -- +-- GNAT COMPILER COMPONENTS -- +-- -- +-- S E M _ C A S E -- +-- -- +-- S p e c -- +-- -- +-- Copyright (C) 1996-2008, 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. -- +-- -- +------------------------------------------------------------------------------ + +-- Package containing the routines to process a list of discrete choices. +-- Such lists can occur in two different constructs: case statements and +-- record variants. We have factorized what used to be two very similar +-- sets of routines in one place. These are not currently used for the +-- aggregate case, since issues with nested aggregates make that case +-- substantially different. + +with Types; use Types; + +package Sem_Case is + + type Choice_Bounds is record + Lo : Node_Id; + Hi : Node_Id; + Node : Node_Id; + end record; + + type Choice_Table_Type is array (Pos range <>) of Choice_Bounds; + -- Table type used to sort the choices present in a case statement, + -- array aggregate or record variant. + + procedure No_OP (C : Node_Id); + -- The no-operation routine. Does absolutely nothing. Can be used + -- in the following generic for the parameter Process_Empty_Choice. + + generic + with function Get_Alternatives (N : Node_Id) return List_Id; + -- Function needed to get to the actual list of case statement + -- alternatives, or array aggregate component associations or + -- record variants from which we can then access the actual lists + -- of discrete choices. N is the node for the original construct + -- i.e. a case statement, an array aggregate or a record variant. + + with function Get_Choices (A : Node_Id) return List_Id; + -- Given a case statement alternative, array aggregate component + -- association or record variant A we need different access functions + -- to get to the actual list of discrete choices. + + with procedure Process_Empty_Choice (Choice : Node_Id); + -- Processing to carry out for an empty Choice + + with procedure Process_Non_Static_Choice (Choice : Node_Id); + -- Processing to carry out for a non static Choice + + with procedure Process_Associated_Node (A : Node_Id); + -- Associated to each case alternative, aggregate component + -- association or record variant A there is a node or list of nodes + -- that need semantic processing. This routine implements that + -- processing. + + package Generic_Choices_Processing is + + function Number_Of_Choices (N : Node_Id) return Nat; + -- Iterates through the choices of N, (N can be a case statement, + -- array aggregate or record variant), counting all the Choice nodes + -- except for the Others choice. + + procedure Analyze_Choices + (N : Node_Id; + Subtyp : Entity_Id; + Choice_Table : out Choice_Table_Type; + Last_Choice : out Nat; + Raises_CE : out Boolean; + Others_Present : out Boolean); + -- From a case statement, array aggregate or record variant N, this + -- routine analyzes the corresponding list of discrete choices. + -- Subtyp is the subtype of the discrete choices. The type against + -- which the discrete choices must be resolved is its base type. + -- + -- On entry Choice_Table must be big enough to contain all the discrete + -- choices encountered. The lower bound of Choice_Table must be one. + -- + -- On exit Choice_Table contains all the static and non empty discrete + -- choices in sorted order. Last_Choice gives the position of the last + -- valid choice in Choice_Table, Choice_Table'First contains the first. + -- We can have Last_Choice < Choice_Table'Last for one (or several) of + -- the following reasons: + -- + -- (a) The list of choices contained a non static choice + -- + -- (b) The list of choices contained an empty choice + -- (something like "1 .. 0 => ") + -- + -- (c) One of the bounds of a discrete choice contains an + -- error or raises constraint error. + -- + -- In one of the bounds of a discrete choice raises a constraint + -- error the flag Raise_CE is set. + -- + -- Finally Others_Present is set to True if an Others choice is present + -- in the list of choices, and in this case the call also sets + -- Others_Discrete_Choices in the N_Others_Choice node. + + end Generic_Choices_Processing; + +end Sem_Case; |