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 2,  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 COPYING.  If not, write --
  19 -- to  the  Free Software Foundation,  51  Franklin  Street,  Fifth  Floor, --
  20 -- Boston, MA 02110-1301, USA.                                              --
  21 --                                                                          --
  22 -- GNAT was originally developed  by the GNAT team at  New York University. --
  23 -- Extensive contributions were provided by Ada Core Technologies Inc.      --
  24 --                                                                          --
  25 ------------------------------------------------------------------------------
  26
  27 --  Expand routines for chapter 6 constructs
  28
  29 with Types; use Types;
  30
  31 package Exp_Ch6 is
  32
  33    procedure Expand_N_Function_Call            (N : Node_Id);
  34    procedure Expand_N_Subprogram_Body          (N : Node_Id);
  35    procedure Expand_N_Subprogram_Body_Stub     (N : Node_Id);
  36    procedure Expand_N_Subprogram_Declaration   (N : Node_Id);
  37    procedure Expand_N_Procedure_Call_Statement (N : Node_Id);
  38
  39    procedure Expand_Call (N : Node_Id);
  40    --  This procedure contains common processing for Expand_N_Function_Call,
  41    --  Expand_N_Procedure_Statement, and Expand_N_Entry_Call.
  42
  43    procedure Freeze_Subprogram (N : Node_Id);
  44    --  generate the appropriate expansions related to Subprogram freeze
  45    --  nodes (e. g. the filling of the corresponding Dispatch Table for
  46    --  Primitive Operations)
  47
  48    --  The following type defines the various forms of allocation used for the
  49    --  results of build-in-place function calls.
  50
  51    type BIP_Allocation_Form is
  52      (Unspecified,
  53       Caller_Allocation,
  54       Secondary_Stack,
  55       Global_Heap,
  56       User_Storage_Pool);
  57
  58    type BIP_Formal_Kind is
  59    --  Ada 2005 (AI-318-02): This type defines the kinds of implicit extra
  60    --  formals created for build-in-place functions. The order of the above
  61    --  enumeration literals matches the order in which the formals are
  62    --  declared. See Sem_Ch6.Create_Extra_Formals.
  63      (BIP_Alloc_Form,
  64       --  Present if result subtype is unconstrained, or if the result type
  65       --  is tagged. Indicates whether the return object is allocated by the
  66       --  caller or callee, and if the callee, whether to use the secondary
  67       --  stack or the heap. See Create_Extra_Formals.
  68       BIP_Final_List,
  69       --  Present if result type has controlled parts. Pointer to caller's
  70       --  finalization list.
  71       BIP_Master,
  72       --  Present if result type contains tasks. Master associated with
  73       --  calling context.
  74       BIP_Activation_Chain,
  75       --  Present if result type contains tasks. Caller's activation chain.
  76       BIP_Object_Access);
  77       --  Present for all build-in-place functions. Address at which to place
  78       --  the return object, or null if BIP_Alloc_Form indicates
  79       --  allocated by callee.
  80       --  ??? We also need to be able to pass in some way to access a
  81       --  user-defined storage pool at some point. And perhaps a constrained
  82       --  flag.
  83
  84    function BIP_Formal_Suffix (Kind : BIP_Formal_Kind) return String;
  85    --  Ada 2005 (AI-318-02): Returns a string to be used as the suffix of names
  86    --  for build-in-place formal parameters of the given kind.
  87
  88    function Build_In_Place_Formal
  89      (Func : Entity_Id;
  90       Kind : BIP_Formal_Kind) return Entity_Id;
  91    --  Ada 2005 (AI-318-02): Locates and returns the entity for the implicit
  92    --  build-in-place formal parameter of the given kind associated with the
  93    --  function Func, and returns its Entity_Id. It is a bug if not found; the
  94    --  caller should ensure this is called only when the extra formal exists.
  95
  96    function Is_Build_In_Place_Function (E : Entity_Id) return Boolean;
  97    --  Ada 2005 (AI-318-02): Returns True if E denotes a function, generic
  98    --  function, or access-to-function type whose result must be built in
  99    --  place; otherwise returns False. For Ada 2005, this is currently
 100    --  restricted to the set of functions whose result subtype is an inherently
 101    --  limited type. In Ada 95, this must be False for inherently limited
 102    --  result types (but currently returns False for all Ada 95 functions).
 103    --  Eventually we plan to support build-in-place for nonlimited types.
 104    --  Build-in-place is usually more efficient for large things, and less
 105    --  efficient for small things. However, we never use build-in-place if the
 106    --  convention is other than Ada, because that would disturb mixed-language
 107    --  programs. Note that for the non-inherently-limited cases, we must make
 108    --  the same decision for Ada 95 and 2005, so that mixed-dialect programs
 109    --  will work.
 110
 111    function Is_Build_In_Place_Function_Call (N : Node_Id) return Boolean;
 112    --  Ada 2005 (AI-318-02): Returns True if N denotes a call to a function
 113    --  that requires handling as a build-in-place call or is a qualified
 114    --  expression applied to such a call; otherwise returns False.
 115
 116    function Is_Build_In_Place_Function_Return (N : Node_Id) return Boolean;
 117    --  Ada 2005 (AI-318-02): Returns True if N is an N_Return_Statement or
 118    --  N_Extended_Return_Statement and it applies to a build-in-place function
 119    --  or generic function.
 120
 121    procedure Make_Build_In_Place_Call_In_Allocator
 122      (Allocator     : Node_Id;
 123       Function_Call : Node_Id);
 124    --  Ada 2005 (AI-318-02): Handle a call to a build-in-place function that
 125    --  occurs as the expression initializing an allocator, by passing access
 126    --  to the allocated object as an additional parameter of the function call.
 127    --  A new access object is declared that is initialized to the result of the
 128    --  allocator, passed to the function, and the allocator is rewritten to
 129    --  refer to that access object. Function_Call must denote either an
 130    --  N_Function_Call node for which Is_Build_In_Place_Call is True, or else
 131    --  an N_Qualified_Expression node applied to such a function call.
 132
 133    procedure Make_Build_In_Place_Call_In_Anonymous_Context
 134      (Function_Call : Node_Id);
 135    --  Ada 2005 (AI-318-02): Handle a call to a build-in-place function that
 136    --  occurs in a context that does not provide a separate object. A temporary
 137    --  object is created to act as the return object and an access to the
 138    --  temporary is passed as an additional parameter of the call. This occurs
 139    --  in contexts such as subprogram call actuals and object renamings.
 140    --  Function_Call must denote either an N_Function_Call node for which
 141    --  Is_Build_In_Place_Call is True, or else an N_Qualified_Expression node
 142    --  applied to such a function call.
 143
 144    procedure Make_Build_In_Place_Call_In_Assignment
 145      (Assign        : Node_Id;
 146       Function_Call : Node_Id);
 147    --  Ada 2005 (AI-318-02): Handle a call to a build-in-place function that
 148    --  occurs as the right-hand side of an assignment statement by passing
 149    --  access to the left-hand side as an additional parameter of the function
 150    --  call. Assign must denote a N_Assignment_Statement. Function_Call must
 151    --  denote either an N_Function_Call node for which Is_Build_In_Place_Call
 152    --  is True, or an N_Qualified_Expression node applied to such a function
 153    --  call.
 154
 155    procedure Make_Build_In_Place_Call_In_Object_Declaration
 156      (Object_Decl   : Node_Id;
 157       Function_Call : Node_Id);
 158    --  Ada 2005 (AI-318-02): Handle a call to a build-in-place function that
 159    --  occurs as the expression initializing an object declaration by
 160    --  passing access to the declared object as an additional parameter of the
 161    --  function call. Function_Call must denote either an N_Function_Call node
 162    --  for which Is_Build_In_Place_Call is True, or an N_Qualified_Expression
 163    --  node applied to such a function call.
 164
 165 end Exp_Ch6;