1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2011, Free Software Foundation, Inc. --
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. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 -- Expand routines for chapter 6 constructs
28 with Types; use Types;
32 procedure Expand_N_Extended_Return_Statement (N : Node_Id);
33 procedure Expand_N_Function_Call (N : Node_Id);
34 procedure Expand_N_Procedure_Call_Statement (N : Node_Id);
35 procedure Expand_N_Simple_Return_Statement (N : Node_Id);
36 procedure Expand_N_Subprogram_Body (N : Node_Id);
37 procedure Expand_N_Subprogram_Body_Stub (N : Node_Id);
38 procedure Expand_N_Subprogram_Declaration (N : Node_Id);
40 procedure Expand_Actuals (N : Node_Id; Subp : Entity_Id);
41 -- For each actual of an in-out or out parameter which is a numeric
42 -- (view) conversion of the form T (A), where A denotes a variable,
43 -- we insert the declaration:
45 -- Temp : T[ := T (A)];
47 -- prior to the call. Then we replace the actual with a reference to Temp,
48 -- and append the assignment:
52 -- after the call. Here TypeA is the actual type of variable A. For out
53 -- parameters, the initial declaration has no expression. If A is not an
54 -- entity name, we generate instead:
56 -- Var : TypeA renames A;
57 -- Temp : T := Var; -- omitting expression for out parameter.
59 -- Var := TypeA (Temp);
61 -- For other in-out parameters, we emit the required constraint checks
62 -- before and/or after the call.
64 -- For all parameter modes, actuals that denote components and slices of
65 -- packed arrays are expanded into suitable temporaries.
67 -- For non-scalar objects that are possibly unaligned, add call by copy
68 -- code (copy in for IN and IN OUT, copy out for OUT and IN OUT).
70 procedure Expand_Call (N : Node_Id);
71 -- This procedure contains common processing for Expand_N_Function_Call,
72 -- Expand_N_Procedure_Statement, and Expand_N_Entry_Call.
74 procedure Freeze_Subprogram (N : Node_Id);
75 -- generate the appropriate expansions related to Subprogram freeze
76 -- nodes (e.g. the filling of the corresponding Dispatch Table for
77 -- Primitive Operations)
79 -- The following type defines the various forms of allocation used for the
80 -- results of build-in-place function calls.
82 type BIP_Allocation_Form is
89 type BIP_Formal_Kind is
90 -- Ada 2005 (AI-318-02): This type defines the kinds of implicit extra
91 -- formals created for build-in-place functions. The order of the above
92 -- enumeration literals matches the order in which the formals are
93 -- declared. See Sem_Ch6.Create_Extra_Formals.
96 -- Present if result subtype is unconstrained, or if the result type
97 -- is tagged. Indicates whether the return object is allocated by the
98 -- caller or callee, and if the callee, whether to use the secondary
99 -- stack or the heap. See Create_Extra_Formals.
101 BIP_Finalization_Master,
102 -- Present if result type needs finalization. Pointer to caller's
103 -- finalization master.
106 -- Present if result type contains tasks. Master associated with
109 BIP_Activation_Chain,
110 -- Present if result type contains tasks. Caller's activation chain
113 -- Present for all build-in-place functions. Address at which to place
114 -- the return object, or null if BIP_Alloc_Form indicates allocated by
117 -- ??? We also need to be able to pass in some way to access a user-
118 -- defined storage pool at some point. And perhaps a constrained flag.
120 function BIP_Formal_Suffix (Kind : BIP_Formal_Kind) return String;
121 -- Ada 2005 (AI-318-02): Returns a string to be used as the suffix of names
122 -- for build-in-place formal parameters of the given kind.
124 function Build_In_Place_Formal
126 Kind : BIP_Formal_Kind) return Entity_Id;
127 -- Ada 2005 (AI-318-02): Locates and returns the entity for the implicit
128 -- build-in-place formal parameter of the given kind associated with the
129 -- function Func, and returns its Entity_Id. It is a bug if not found; the
130 -- caller should ensure this is called only when the extra formal exists.
132 function Is_Build_In_Place_Function (E : Entity_Id) return Boolean;
133 -- Ada 2005 (AI-318-02): Returns True if E denotes a function, generic
134 -- function, or access-to-function type whose result must be built in
135 -- place; otherwise returns False. For Ada 2005, this is currently
136 -- restricted to the set of functions whose result subtype is an inherently
137 -- limited type. In Ada 95, this must be False for inherently limited
138 -- result types (but currently returns False for all Ada 95 functions).
139 -- Eventually we plan to support build-in-place for nonlimited types.
140 -- Build-in-place is usually more efficient for large things, and less
141 -- efficient for small things. However, we never use build-in-place if the
142 -- convention is other than Ada, because that would disturb mixed-language
143 -- programs. Note that for the non-inherently-limited cases, we must make
144 -- the same decision for Ada 95 and 2005, so that mixed-dialect programs
147 function Is_Build_In_Place_Function_Call (N : Node_Id) return Boolean;
148 -- Ada 2005 (AI-318-02): Returns True if N denotes a call to a function
149 -- that requires handling as a build-in-place call or is a qualified
150 -- expression applied to such a call; otherwise returns False.
152 function Is_Null_Procedure (Subp : Entity_Id) return Boolean;
153 -- Predicate to recognize stubbed procedures and null procedures, which
154 -- can be inlined unconditionally in all cases.
156 procedure Make_Build_In_Place_Call_In_Allocator
157 (Allocator : Node_Id;
158 Function_Call : Node_Id);
159 -- Ada 2005 (AI-318-02): Handle a call to a build-in-place function that
160 -- occurs as the expression initializing an allocator, by passing access
161 -- to the allocated object as an additional parameter of the function call.
162 -- A new access object is declared that is initialized to the result of the
163 -- allocator, passed to the function, and the allocator is rewritten to
164 -- refer to that access object. Function_Call must denote either an
165 -- N_Function_Call node for which Is_Build_In_Place_Call is True, or else
166 -- an N_Qualified_Expression node applied to such a function call.
168 procedure Make_Build_In_Place_Call_In_Anonymous_Context
169 (Function_Call : Node_Id);
170 -- Ada 2005 (AI-318-02): Handle a call to a build-in-place function that
171 -- occurs in a context that does not provide a separate object. A temporary
172 -- object is created to act as the return object and an access to the
173 -- temporary is passed as an additional parameter of the call. This occurs
174 -- in contexts such as subprogram call actuals and object renamings.
175 -- Function_Call must denote either an N_Function_Call node for which
176 -- Is_Build_In_Place_Call is True, or else an N_Qualified_Expression node
177 -- applied to such a function call.
179 procedure Make_Build_In_Place_Call_In_Assignment
181 Function_Call : Node_Id);
182 -- Ada 2005 (AI-318-02): Handle a call to a build-in-place function that
183 -- occurs as the right-hand side of an assignment statement by passing
184 -- access to the left-hand side as an additional parameter of the function
185 -- call. Assign must denote a N_Assignment_Statement. Function_Call must
186 -- denote either an N_Function_Call node for which Is_Build_In_Place_Call
187 -- is True, or an N_Qualified_Expression node applied to such a function
190 procedure Make_Build_In_Place_Call_In_Object_Declaration
191 (Object_Decl : Node_Id;
192 Function_Call : Node_Id);
193 -- Ada 2005 (AI-318-02): Handle a call to a build-in-place function that
194 -- occurs as the expression initializing an object declaration by
195 -- passing access to the declared object as an additional parameter of the
196 -- function call. Function_Call must denote either an N_Function_Call node
197 -- for which Is_Build_In_Place_Call is True, or an N_Qualified_Expression
198 -- node applied to such a function call.
200 function Needs_BIP_Finalization_Master (Func_Id : Entity_Id) return Boolean;
201 -- Ada 2005 (AI-318-02): Return True if the function needs an implicit
202 -- finalization master implicit parameter.
204 function Needs_BIP_Alloc_Form (Func_Id : Entity_Id) return Boolean;
205 -- Ada 2005 (AI-318-02): Return True if the function needs an implicit
206 -- BIP_Alloc_Form parameter (see type BIP_Formal_Kind).
208 function Needs_Result_Accessibility_Level
209 (Func_Id : Entity_Id) return Boolean;
210 -- Ada 2012 (AI05-0234): Return True if the function needs an implicit
211 -- parameter to identify the accessibility level of the function result
212 -- "determined by the point of call".
214 procedure Add_Extra_Actual_To_Call
215 (Subprogram_Call : Node_Id;
216 Extra_Formal : Entity_Id;
217 Extra_Actual : Node_Id);
218 -- Adds Extra_Actual as a named parameter association for the formal
219 -- Extra_Formal in Subprogram_Call.