gcc/ada/exp_ch6.ads

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT COMPILER COMPONENTS                         --
   4 --                                                                          --
   5 --                              E X P _ C H 6                               --
   6 --                                                                          --
   7 --                                 S p e c                                  --
   8 --                                                                          --
   9 --          Copyright (C) 1992-2007, Free Software Foundation, Inc.         --
  10 --                                                                          --
  11 -- GNAT is free software;  you can  redistribute it  and/or modify it under --
  12 -- terms of the  GNU General Public License as published  by the Free Soft- --
  13 -- ware  Foundation;  either version 3,  or (at your option) any later ver- --
  14 -- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
  15 -- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
  16 -- or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License --
  17 -- for  more details.  You should have  received  a copy of the GNU General --
  18 -- Public License  distributed with GNAT; see file COPYING3.  If not, go to --
  19 -- http://www.gnu.org/licenses for a complete copy of the license.          --
  20 --                                                                          --
  21 -- GNAT was originally developed  by the GNAT team at  New York University. --
  22 -- Extensive contributions were provided by Ada Core Technologies Inc.      --
  23 --                                                                          --
  24 ------------------------------------------------------------------------------
  25
  26 --  Expand routines for chapter 6 constructs
  27
  28 with Types; use Types;
  29
  30 package Exp_Ch6 is
  31
  32    procedure Expand_N_Function_Call            (N : Node_Id);
  33    procedure Expand_N_Subprogram_Body          (N : Node_Id);
  34    procedure Expand_N_Subprogram_Body_Stub     (N : Node_Id);
  35    procedure Expand_N_Subprogram_Declaration   (N : Node_Id);
  36    procedure Expand_N_Procedure_Call_Statement (N : Node_Id);
  37
  38    procedure Expand_Call (N : Node_Id);
  39    --  This procedure contains common processing for Expand_N_Function_Call,
  40    --  Expand_N_Procedure_Statement, and Expand_N_Entry_Call.
  41
  42    procedure Freeze_Subprogram (N : Node_Id);
  43    --  generate the appropriate expansions related to Subprogram freeze
  44    --  nodes (e.g. the filling of the corresponding Dispatch Table for
  45    --  Primitive Operations)
  46
  47    --  The following type defines the various forms of allocation used for the
  48    --  results of build-in-place function calls.
  49
  50    type BIP_Allocation_Form is
  51      (Unspecified,
  52       Caller_Allocation,
  53       Secondary_Stack,
  54       Global_Heap,
  55       User_Storage_Pool);
  56
  57    type BIP_Formal_Kind is
  58    --  Ada 2005 (AI-318-02): This type defines the kinds of implicit extra
  59    --  formals created for build-in-place functions. The order of the above
  60    --  enumeration literals matches the order in which the formals are
  61    --  declared. See Sem_Ch6.Create_Extra_Formals.
  62      (BIP_Alloc_Form,
  63       --  Present if result subtype is unconstrained, or if the result type
  64       --  is tagged. Indicates whether the return object is allocated by the
  65       --  caller or callee, and if the callee, whether to use the secondary
  66       --  stack or the heap. See Create_Extra_Formals.
  67       BIP_Final_List,
  68       --  Present if result type has controlled parts. Pointer to caller's
  69       --  finalization list.
  70       BIP_Master,
  71       --  Present if result type contains tasks. Master associated with
  72       --  calling context.
  73       BIP_Activation_Chain,
  74       --  Present if result type contains tasks. Caller's activation chain
  75       BIP_Object_Access);
  76       --  Present for all build-in-place functions. Address at which to place
  77       --  the return object, or null if BIP_Alloc_Form indicates
  78       --  allocated by callee.
  79       --  ??? We also need to be able to pass in some way to access a
  80       --  user-defined storage pool at some point. And perhaps a constrained
  81       --  flag.
  82
  83    function BIP_Formal_Suffix (Kind : BIP_Formal_Kind) return String;
  84    --  Ada 2005 (AI-318-02): Returns a string to be used as the suffix of names
  85    --  for build-in-place formal parameters of the given kind.
  86
  87    function Build_In_Place_Formal
  88      (Func : Entity_Id;
  89       Kind : BIP_Formal_Kind) return Entity_Id;
  90    --  Ada 2005 (AI-318-02): Locates and returns the entity for the implicit
  91    --  build-in-place formal parameter of the given kind associated with the
  92    --  function Func, and returns its Entity_Id. It is a bug if not found; the
  93    --  caller should ensure this is called only when the extra formal exists.
  94
  95    function Is_Build_In_Place_Function (E : Entity_Id) return Boolean;
  96    --  Ada 2005 (AI-318-02): Returns True if E denotes a function, generic
  97    --  function, or access-to-function type whose result must be built in
  98    --  place; otherwise returns False. For Ada 2005, this is currently
  99    --  restricted to the set of functions whose result subtype is an inherently
 100    --  limited type. In Ada 95, this must be False for inherently limited
 101    --  result types (but currently returns False for all Ada 95 functions).
 102    --  Eventually we plan to support build-in-place for nonlimited types.
 103    --  Build-in-place is usually more efficient for large things, and less
 104    --  efficient for small things. However, we never use build-in-place if the
 105    --  convention is other than Ada, because that would disturb mixed-language
 106    --  programs. Note that for the non-inherently-limited cases, we must make
 107    --  the same decision for Ada 95 and 2005, so that mixed-dialect programs
 108    --  will work.
 109
 110    function Is_Build_In_Place_Function_Call (N : Node_Id) return Boolean;
 111    --  Ada 2005 (AI-318-02): Returns True if N denotes a call to a function
 112    --  that requires handling as a build-in-place call or is a qualified
 113    --  expression applied to such a call; otherwise returns False.
 114
 115    function Is_Build_In_Place_Function_Return (N : Node_Id) return Boolean;
 116    --  Ada 2005 (AI-318-02): Returns True if N is an N_Simple_Return_Statement
 117    --  or N_Extended_Return_Statement and it applies to a build-in-place
 118    --  function or generic function.
 119
 120    procedure Make_Build_In_Place_Call_In_Allocator
 121      (Allocator     : Node_Id;
 122       Function_Call : Node_Id);
 123    --  Ada 2005 (AI-318-02): Handle a call to a build-in-place function that
 124    --  occurs as the expression initializing an allocator, by passing access
 125    --  to the allocated object as an additional parameter of the function call.
 126    --  A new access object is declared that is initialized to the result of the
 127    --  allocator, passed to the function, and the allocator is rewritten to
 128    --  refer to that access object. Function_Call must denote either an
 129    --  N_Function_Call node for which Is_Build_In_Place_Call is True, or else
 130    --  an N_Qualified_Expression node applied to such a function call.
 131
 132    procedure Make_Build_In_Place_Call_In_Anonymous_Context
 133      (Function_Call : Node_Id);
 134    --  Ada 2005 (AI-318-02): Handle a call to a build-in-place function that
 135    --  occurs in a context that does not provide a separate object. A temporary
 136    --  object is created to act as the return object and an access to the
 137    --  temporary is passed as an additional parameter of the call. This occurs
 138    --  in contexts such as subprogram call actuals and object renamings.
 139    --  Function_Call must denote either an N_Function_Call node for which
 140    --  Is_Build_In_Place_Call is True, or else an N_Qualified_Expression node
 141    --  applied to such a function call.
 142
 143    procedure Make_Build_In_Place_Call_In_Assignment
 144      (Assign        : Node_Id;
 145       Function_Call : Node_Id);
 146    --  Ada 2005 (AI-318-02): Handle a call to a build-in-place function that
 147    --  occurs as the right-hand side of an assignment statement by passing
 148    --  access to the left-hand side as an additional parameter of the function
 149    --  call. Assign must denote a N_Assignment_Statement. Function_Call must
 150    --  denote either an N_Function_Call node for which Is_Build_In_Place_Call
 151    --  is True, or an N_Qualified_Expression node applied to such a function
 152    --  call.
 153
 154    procedure Make_Build_In_Place_Call_In_Object_Declaration
 155      (Object_Decl   : Node_Id;
 156       Function_Call : Node_Id);
 157    --  Ada 2005 (AI-318-02): Handle a call to a build-in-place function that
 158    --  occurs as the expression initializing an object declaration by
 159    --  passing access to the declared object as an additional parameter of the
 160    --  function call. Function_Call must denote either an N_Function_Call node
 161    --  for which Is_Build_In_Place_Call is True, or an N_Qualified_Expression
 162    --  node applied to such a function call.
 163
 164 end Exp_Ch6;