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Diffstat (limited to 'gcc-4.7/gcc/ada/layout.ads')
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diff --git a/gcc-4.7/gcc/ada/layout.ads b/gcc-4.7/gcc/ada/layout.ads new file mode 100644 index 000000000..c20458768 --- /dev/null +++ b/gcc-4.7/gcc/ada/layout.ads @@ -0,0 +1,83 @@ +------------------------------------------------------------------------------ +-- -- +-- GNAT COMPILER COMPONENTS -- +-- -- +-- L A Y O U T -- +-- -- +-- S p e c -- +-- -- +-- Copyright (C) 2000-2007, 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 package does front-end layout of types and objects. The result is +-- to annotate the tree with information on size and alignment of types +-- and objects. How much layout is performed depends on the setting of the +-- target dependent parameter Backend_Layout. + +with Types; use Types; + +package Layout is + + -- The following procedures are called from Freeze, so all entities + -- for types and objects that get frozen (which should be all such + -- entities which are seen by the back end) will get layed out by one + -- of these two procedures. + + procedure Layout_Type (E : Entity_Id); + -- This procedure may set or adjust the fields Esize, RM_Size and + -- Alignment in the non-generic type or subtype entity E. If the + -- Backend_Layout switch is False, then it is guaranteed that all + -- three fields will be properly set on return. Regardless of the + -- Backend_Layout value, it is guaranteed that all discrete types + -- will have both Esize and RM_Size fields set on return (since + -- these are static values). Note that Layout_Type is not called + -- for generic types, since these play no part in code generation, + -- and hence representation aspects are irrelevant. + + procedure Layout_Object (E : Entity_Id); + -- E is either a variable (E_Variable), a constant (E_Constant), + -- a loop parameter (E_Loop_Parameter), or a formal parameter of + -- a non-generic subprogram (E_In_Parameter, E_In_Out_Parameter, + -- or E_Out_Parameter). This procedure may set or adjust the + -- Esize and Alignment fields of E. If Backend_Layout is False, + -- then it is guaranteed that both fields will be properly set + -- on return. If the Esize is still unknown in the latter case, + -- it means that the object must be allocated dynamically, since + -- its length is not known at compile time. + + -- The following are utility routines, called from various places + + procedure Adjust_Esize_Alignment (E : Entity_Id); + -- E is the entity for a type or object. This procedure checks that the + -- size and alignment are compatible, and if not either gives an error + -- message if they cannot be adjusted or else adjusts them appropriately. + + procedure Set_Discrete_RM_Size (Def_Id : Entity_Id); + -- Set proper RM_Size for discrete size, this is normally the minimum + -- number of bits to accommodate the range given, except in the case + -- where the subtype statically matches the first subtype, in which + -- case the size must be copied from the first subtype. For generic + -- types, the RM_Size is simply set to zero. This routine also sets + -- the Is_Constrained flag in Def_Id. + + procedure Set_Elem_Alignment (E : Entity_Id); + -- The front end always sets alignments for elementary types by calling + -- this procedure. Note that we have to do this for discrete types (since + -- the Alignment attribute is static), so we might as well do it for all + -- elementary types, since the processing is the same. + +end Layout; |