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Diffstat (limited to 'gcc-4.2.1/gcc/ada/sem_ch13.ads')
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diff --git a/gcc-4.2.1/gcc/ada/sem_ch13.ads b/gcc-4.2.1/gcc/ada/sem_ch13.ads new file mode 100644 index 000000000..f15601a1c --- /dev/null +++ b/gcc-4.2.1/gcc/ada/sem_ch13.ads @@ -0,0 +1,158 @@ +------------------------------------------------------------------------------ +-- -- +-- GNAT COMPILER COMPONENTS -- +-- -- +-- S E M _ C H 1 3 -- +-- -- +-- S p e c -- +-- -- +-- Copyright (C) 1992-2004 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. -- +-- -- +------------------------------------------------------------------------------ + +with Types; use Types; +with Uintp; use Uintp; + +package Sem_Ch13 is + procedure Analyze_At_Clause (N : Node_Id); + procedure Analyze_Attribute_Definition_Clause (N : Node_Id); + procedure Analyze_Enumeration_Representation_Clause (N : Node_Id); + procedure Analyze_Free_Statement (N : Node_Id); + procedure Analyze_Record_Representation_Clause (N : Node_Id); + procedure Analyze_Code_Statement (N : Node_Id); + + procedure Initialize; + -- Initialize internal tables for new compilation + + procedure Set_Enum_Esize (T : Entity_Id); + -- This routine sets the Esize field for an enumeration type T, based + -- on the current representation information available for T. Note that + -- the setting of the RM_Size field is not affected. This routine also + -- initializes the alignment field to zero. + + function Minimum_Size + (T : Entity_Id; + Biased : Boolean := False) return Nat; + -- Given an elementary type, determines the minimum number of bits required + -- to represent all values of the type. This function may not be called + -- with any other types. If the flag Biased is set True, then the minimum + -- size calculation that biased representation is used in the case of a + -- discrete type, e.g. the range 7..8 gives a minimum size of 4 with + -- Biased set to False, and 1 with Biased set to True. Note that the + -- biased parameter only has an effect if the type is not biased, it + -- causes Minimum_Size to indicate the minimum size of an object with + -- the given type, of the size the type would have if it were biased. If + -- the type is already biased, then Minimum_Size returns the biased size, + -- regardless of the setting of Biased. Also, fixed-point types are never + -- biased in the current implementation. + + procedure Check_Constant_Address_Clause (Expr : Node_Id; U_Ent : Entity_Id); + -- Expr is an expression for an address clause. This procedure checks + -- that the expression is constant, in the limited sense that it is safe + -- to evaluate it at the point the object U_Ent is declared, rather than + -- at the point of the address clause. The condition for this to be true + -- is that the expression has no variables, no constants declared after + -- U_Ent, and no calls to non-pure functions. If this condition is not + -- met, then an appropriate error message is posted. This check is applied + -- at the point an object with an address clause is frozen, as well as for + -- address clauses for tasks and entries. + + procedure Check_Size + (N : Node_Id; + T : Entity_Id; + Siz : Uint; + Biased : out Boolean); + -- Called when size Siz is specified for subtype T. This subprogram checks + -- that the size is appropriate, posting errors on node N as required. + -- This check is effective for elementary types and bit-packed arrays. + -- For other non-elementary types, a check is only made if an explicit + -- size has been given for the type (and the specified size must match). + -- The parameter Biased is set False if the size specified did not require + -- the use of biased representation, and True if biased representation + -- was required to meet the size requirement. Note that Biased is only + -- set if the type is not currently biased, but biasing it is the only + -- way to meet the requirement. If the type is currently biased, then + -- this biased size is used in the initial check, and Biased is False. + -- If the size is too small, and an error message is given, then both + -- Esize and RM_Size are reset to the allowed minimum value in T. + + function Rep_Item_Too_Early (T : Entity_Id; N : Node_Id) return Boolean; + -- Called at the start of processing a representation clause or a + -- representation pragma. Used to check that the representation item + -- is not being applied to an incompleted type or to a generic formal + -- type or a type derived from a generic formal type. Returns False if + -- no such error occurs. If this error does occur, appropriate error + -- messages are posted on node N, and True is returned. + + function Rep_Item_Too_Late + (T : Entity_Id; + N : Node_Id; + FOnly : Boolean := False) return Boolean; + -- Called at the start of processing a representation clause or a + -- representation pragma. Used to check that a representation item + -- for entity T does not appear too late (according to the rules in + -- RM 13.1(9) and RM 13.1(10)). N is the associated node, which in + -- the pragma case is the pragma or representation clause itself, used + -- for placing error messages if the item is too late. + -- + -- Fonly is a flag that causes only the freezing rule (para 9) to be + -- applied, and the tests of para 10 are skipped. This is appropriate + -- for both subtype related attributes (Alignment and Size) and for + -- stream attributes, which, although certainly not subtype related + -- attributes, clearly should not be subject to the para 10 restrictions + -- (see AI95-00137). Similarly, we also skip the para 10 restrictions for + -- the Storage_Size case where they also clearly do not apply. + -- + -- If the rep item is too late, an appropriate message is output and + -- True is returned, which is a signal that the caller should abandon + -- processing for the item. If the item is not too late, then False + -- is returned, and the caller can continue processing the item. + -- + -- If no error is detected, this call also as a side effect links the + -- representation item onto the head of the representation item chain + -- (referenced by the First_Rep_Item field of the entity). + -- + -- Note: Rep_Item_Too_Late must be called with the underlying type in + -- the case of a private or incomplete type. The protocol is to first + -- check for Rep_Item_Too_Early using the initial entity, then take the + -- underlying type, then call Rep_Item_Too_Late on the result. + + function Same_Representation (Typ1, Typ2 : Entity_Id) return Boolean; + -- Given two types, where the two types are related by possible derivation, + -- determines if the two types have the same representation, or different + -- representations, requiring the special processing for representation + -- change. A False result is possible only for array, enumeration or + -- record types. + + procedure Validate_Unchecked_Conversion + (N : Node_Id; + Act_Unit : Entity_Id); + -- Validate a call to unchecked conversion. N is the node for the actual + -- instantiation, which is used only for error messages. Act_Unit is the + -- entity for the instantiation, from which the actual types etc for this + -- instantiation can be determined. This procedure makes an entry in a + -- table and/or generates an N_Validate_Unchecked_Conversion node. The + -- actual checking is done in Validate_Unchecked_Conversions or in the + -- back end as required. + + procedure Validate_Unchecked_Conversions; + -- This routine is called after calling the backend to validate + -- unchecked conversions for size and alignment appropriateness. + -- The reason it is called that late is to take advantage of any + -- back-annotation of size and alignment performed by the backend. + +end Sem_Ch13; |