PR c++/86728 - C variadic generic lambda.
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1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT COMPILER COMPONENTS --
4 -- --
5 -- E X P _ C H 6 --
6 -- --
7 -- S p e c --
8 -- --
9 -- Copyright (C) 1992-2018, 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 ------------------------------------------------------------------------------
26 -- Expand routines for chapter 6 constructs
28 with Types; use Types;
30 package Exp_Ch6 is
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_Call (N : Node_Id);
41 -- This procedure contains common processing for Expand_N_Function_Call,
42 -- Expand_N_Procedure_Statement, and Expand_N_Entry_Call.
44 procedure Freeze_Subprogram (N : Node_Id);
45 -- generate the appropriate expansions related to Subprogram freeze
46 -- nodes (e.g. the filling of the corresponding Dispatch Table for
47 -- Primitive Operations)
49 -- The following type defines the various forms of allocation used for the
50 -- results of build-in-place function calls.
52 type BIP_Allocation_Form is
53 (Unspecified,
54 Caller_Allocation,
55 Secondary_Stack,
56 Global_Heap,
57 User_Storage_Pool);
59 type BIP_Formal_Kind is
60 -- Ada 2005 (AI-318-02): This type defines the kinds of implicit extra
61 -- formals created for build-in-place functions. The order of these
62 -- enumeration literals matches the order in which the formals are
63 -- declared. See Sem_Ch6.Create_Extra_Formals.
65 (BIP_Alloc_Form,
66 -- Present if result subtype is unconstrained or tagged. Indicates
67 -- whether the return object is allocated by the caller or callee, and
68 -- if the callee, whether to use the secondary stack or the heap. See
69 -- Create_Extra_Formals.
71 BIP_Storage_Pool,
72 -- Present if result subtype is unconstrained or tagged. If
73 -- BIP_Alloc_Form = User_Storage_Pool, this is a pointer to the pool
74 -- (of type access to Root_Storage_Pool'Class). Otherwise null.
76 BIP_Finalization_Master,
77 -- Present if result type needs finalization. Pointer to caller's
78 -- finalization master.
80 BIP_Task_Master,
81 -- Present if result type contains tasks. Master associated with
82 -- calling context.
84 BIP_Activation_Chain,
85 -- Present if result type contains tasks. Caller's activation chain
87 BIP_Object_Access);
88 -- Present for all build-in-place functions. Address at which to place
89 -- the return object, or null if BIP_Alloc_Form indicates allocated by
90 -- callee.
92 -- ??? We might also need to be able to pass in a constrained flag.
94 procedure Add_Extra_Actual_To_Call
95 (Subprogram_Call : Node_Id;
96 Extra_Formal : Entity_Id;
97 Extra_Actual : Node_Id);
98 -- Adds Extra_Actual as a named parameter association for the formal
99 -- Extra_Formal in Subprogram_Call.
101 function BIP_Formal_Suffix (Kind : BIP_Formal_Kind) return String;
102 -- Ada 2005 (AI-318-02): Returns a string to be used as the suffix of names
103 -- for build-in-place formal parameters of the given kind.
105 function Build_In_Place_Formal
106 (Func : Entity_Id;
107 Kind : BIP_Formal_Kind) return Entity_Id;
108 -- Ada 2005 (AI-318-02): Locates and returns the entity for the implicit
109 -- build-in-place formal parameter of the given kind associated with the
110 -- function Func, and returns its Entity_Id. It is a bug if not found; the
111 -- caller should ensure this is called only when the extra formal exists.
113 function Build_Procedure_Body_Form
114 (Func_Id : Entity_Id; Func_Body : Node_Id) return Node_Id;
115 -- Create a procedure body which emulates the behavior of function Func_Id.
116 -- Func_Body is the root of the body of the function before its analysis.
117 -- The returned node is the root of the procedure body which will replace
118 -- the original function body, which is not needed for the C program.
120 function Is_Build_In_Place_Result_Type (Typ : Entity_Id) return Boolean;
121 -- Ada 2005 (AI-318-02): Returns True if functions returning the type use
122 -- build-in-place protocols. For inherently limited types, this must be
123 -- True in >= Ada 2005, and must be False in Ada 95. For other types, it
124 -- can be True or False, and the decision should be based on efficiency,
125 -- and should be the same for all language versions, so that mixed-dialect
126 -- programs will work.
128 -- For inherently limited types in Ada 2005, True means that calls will
129 -- actually be build-in-place in all cases. For other types, build-in-place
130 -- will be used when possible, but we need to make a copy at the call site
131 -- in some cases, notably assignment statements.
133 function Is_Build_In_Place_Function (E : Entity_Id) return Boolean;
134 -- Ada 2005 (AI-318-02): Returns True if E denotes a function, generic
135 -- function, or access-to-function type for which
136 -- Is_Build_In_Place_Result_Type is True. However, we never use
137 -- build-in-place if the convention is other than Ada, because that would
138 -- disturb mixed-language programs.
140 function Is_Build_In_Place_Function_Call (N : Node_Id) return Boolean;
141 -- Ada 2005 (AI-318-02): Returns True if N denotes a call to a function
142 -- that requires handling as a build-in-place call (possibly qualified or
143 -- converted).
145 function Is_Null_Procedure (Subp : Entity_Id) return Boolean;
146 -- Predicate to recognize stubbed procedures and null procedures, which
147 -- can be inlined unconditionally in all cases.
149 procedure Make_Build_In_Place_Call_In_Allocator
150 (Allocator : Node_Id;
151 Function_Call : Node_Id);
152 -- Ada 2005 (AI-318-02): Handle a call to a build-in-place function that
153 -- occurs as the expression initializing an allocator, by passing access
154 -- to the allocated object as an additional parameter of the function call.
155 -- A new access object is declared that is initialized to the result of the
156 -- allocator, passed to the function, and the allocator is rewritten to
157 -- refer to that access object. Function_Call must denote either an
158 -- N_Function_Call node for which Is_Build_In_Place_Call is True, or else
159 -- an N_Qualified_Expression node applied to such a function call.
161 procedure Make_Build_In_Place_Call_In_Anonymous_Context
162 (Function_Call : Node_Id);
163 -- Ada 2005 (AI-318-02): Handle a call to a build-in-place function that
164 -- occurs in a context that does not provide a separate object. A temporary
165 -- object is created to act as the return object and an access to the
166 -- temporary is passed as an additional parameter of the call. This occurs
167 -- in contexts such as subprogram call actuals and object renamings.
168 -- Function_Call must denote either an N_Function_Call node for which
169 -- Is_Build_In_Place_Call is True, or else an N_Qualified_Expression node
170 -- applied to such a function call.
172 procedure Make_Build_In_Place_Call_In_Assignment
173 (Assign : Node_Id;
174 Function_Call : Node_Id);
175 -- Ada 2005 (AI-318-02): Handle a call to a build-in-place function that
176 -- occurs as the right-hand side of an assignment statement by passing
177 -- access to the left-hand side as an additional parameter of the function
178 -- call. Assign must denote a N_Assignment_Statement. Function_Call must
179 -- denote either an N_Function_Call node for which Is_Build_In_Place_Call
180 -- is True, or an N_Qualified_Expression node applied to such a function
181 -- call.
183 procedure Make_Build_In_Place_Call_In_Object_Declaration
184 (Obj_Decl : Node_Id;
185 Function_Call : Node_Id);
186 -- Ada 2005 (AI-318-02): Handle a call to a build-in-place function that
187 -- occurs as the expression initializing an object declaration by
188 -- passing access to the declared object as an additional parameter of the
189 -- function call. Function_Call must denote either an N_Function_Call node
190 -- for which Is_Build_In_Place_Call is True, or an N_Qualified_Expression
191 -- node applied to such a function call.
193 procedure Make_Build_In_Place_Iface_Call_In_Allocator
194 (Allocator : Node_Id;
195 Function_Call : Node_Id);
196 -- Ada 2005 (AI-318-02): Handle a call to a build-in-place function that
197 -- occurs as the expression initializing an allocator, by passing access
198 -- to the allocated object as an additional parameter of the function call.
199 -- Function_Call must denote an expression containing a BIP function call
200 -- and an enclosing call to Ada.Tags.Displace to displace the pointer to
201 -- the returned BIP object to reference the secondary dispatch table of
202 -- an interface.
204 procedure Make_Build_In_Place_Iface_Call_In_Anonymous_Context
205 (Function_Call : Node_Id);
206 -- Ada 2005 (AI-318-02): Handle a call to a build-in-place function that
207 -- occurs in a context that does not provide a separate object. A temporary
208 -- object is created to act as the return object and an access to the
209 -- temporary is passed as an additional parameter of the call. This occurs
210 -- in contexts such as subprogram call actuals and object renamings.
211 -- Function_Call must denote an expression containing a BIP function call
212 -- and an enclosing call to Ada.Tags.Displace to displace the pointer to
213 -- the returned BIP object to reference the secondary dispatch table of
214 -- an interface.
216 procedure Make_Build_In_Place_Iface_Call_In_Object_Declaration
217 (Obj_Decl : Node_Id;
218 Function_Call : Node_Id);
219 -- Ada 2005 (AI-318-02): Handle a call to a build-in-place function that
220 -- occurs as the expression initializing an object declaration by passing
221 -- access to the declared object as an additional parameter of the function
222 -- call. Function_Call must denote an expression containing a BIP function
223 -- call and an enclosing call to Ada.Tags.Displace to displace the pointer
224 -- to the returned BIP object to reference the secondary dispatch table of
225 -- an interface.
227 procedure Make_CPP_Constructor_Call_In_Allocator
228 (Allocator : Node_Id;
229 Function_Call : Node_Id);
230 -- Handle a call to a CPP constructor that occurs as the expression that
231 -- initializes an allocator, by passing access to the allocated object as
232 -- an additional parameter of the constructor call. A new access object is
233 -- declared that is initialized to the result of the allocator, passed to
234 -- the constructor, and the allocator is rewritten to refer to that access
235 -- object. Function_Call must denote a call to a CPP_Constructor function.
237 function Needs_BIP_Alloc_Form (Func_Id : Entity_Id) return Boolean;
238 -- Ada 2005 (AI-318-02): Return True if the function needs an implicit
239 -- BIP_Alloc_Form parameter (see type BIP_Formal_Kind).
241 function Needs_BIP_Finalization_Master (Func_Id : Entity_Id) return Boolean;
242 -- Ada 2005 (AI-318-02): Return True if the result subtype of function
243 -- Func_Id might need finalization actions. This includes build-in-place
244 -- functions with tagged result types, since they can be invoked via
245 -- dispatching calls, and descendant types may require finalization.
247 function Needs_Result_Accessibility_Level
248 (Func_Id : Entity_Id) return Boolean;
249 -- Ada 2012 (AI05-0234): Return True if the function needs an implicit
250 -- parameter to identify the accessibility level of the function result
251 -- "determined by the point of call".
253 function Unqual_BIP_Iface_Function_Call (Expr : Node_Id) return Node_Id;
254 -- Return the inner BIP function call removing any qualification from Expr
255 -- including qualified expressions, type conversions, references, unchecked
256 -- conversions and calls to displace the pointer to the object, if Expr is
257 -- an expression containing a call displacing the pointer to the BIP object
258 -- to reference the secondary dispatch table of an interface; otherwise
259 -- return Empty.
261 end Exp_Ch6;