1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
|
------------------------------------------------------------------------------
-- --
-- GNAT COMPILER COMPONENTS --
-- --
-- E X P _ C H 6 --
-- --
-- S p e c --
-- --
-- Copyright (C) 1992-2018, 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. --
-- --
------------------------------------------------------------------------------
-- Expand routines for chapter 6 constructs
with Types; use Types;
package Exp_Ch6 is
procedure Expand_N_Extended_Return_Statement (N : Node_Id);
procedure Expand_N_Function_Call (N : Node_Id);
procedure Expand_N_Procedure_Call_Statement (N : Node_Id);
procedure Expand_N_Simple_Return_Statement (N : Node_Id);
procedure Expand_N_Subprogram_Body (N : Node_Id);
procedure Expand_N_Subprogram_Body_Stub (N : Node_Id);
procedure Expand_N_Subprogram_Declaration (N : Node_Id);
procedure Expand_Call (N : Node_Id);
-- This procedure contains common processing for Expand_N_Function_Call,
-- Expand_N_Procedure_Statement, and Expand_N_Entry_Call.
procedure Freeze_Subprogram (N : Node_Id);
-- generate the appropriate expansions related to Subprogram freeze
-- nodes (e.g. the filling of the corresponding Dispatch Table for
-- Primitive Operations)
-- The following type defines the various forms of allocation used for the
-- results of build-in-place function calls.
type BIP_Allocation_Form is
(Unspecified,
Caller_Allocation,
Secondary_Stack,
Global_Heap,
User_Storage_Pool);
type BIP_Formal_Kind is
-- Ada 2005 (AI-318-02): This type defines the kinds of implicit extra
-- formals created for build-in-place functions. The order of these
-- enumeration literals matches the order in which the formals are
-- declared. See Sem_Ch6.Create_Extra_Formals.
(BIP_Alloc_Form,
-- Present if result subtype is unconstrained or tagged. Indicates
-- whether the return object is allocated by the caller or callee, and
-- if the callee, whether to use the secondary stack or the heap. See
-- Create_Extra_Formals.
BIP_Storage_Pool,
-- Present if result subtype is unconstrained or tagged. If
-- BIP_Alloc_Form = User_Storage_Pool, this is a pointer to the pool
-- (of type access to Root_Storage_Pool'Class). Otherwise null.
BIP_Finalization_Master,
-- Present if result type needs finalization. Pointer to caller's
-- finalization master.
BIP_Task_Master,
-- Present if result type contains tasks. Master associated with
-- calling context.
BIP_Activation_Chain,
-- Present if result type contains tasks. Caller's activation chain
BIP_Object_Access);
-- Present for all build-in-place functions. Address at which to place
-- the return object, or null if BIP_Alloc_Form indicates allocated by
-- callee.
--
-- ??? We might also need to be able to pass in a constrained flag.
procedure Add_Extra_Actual_To_Call
(Subprogram_Call : Node_Id;
Extra_Formal : Entity_Id;
Extra_Actual : Node_Id);
-- Adds Extra_Actual as a named parameter association for the formal
-- Extra_Formal in Subprogram_Call.
function BIP_Formal_Suffix (Kind : BIP_Formal_Kind) return String;
-- Ada 2005 (AI-318-02): Returns a string to be used as the suffix of names
-- for build-in-place formal parameters of the given kind.
function Build_In_Place_Formal
(Func : Entity_Id;
Kind : BIP_Formal_Kind) return Entity_Id;
-- Ada 2005 (AI-318-02): Locates and returns the entity for the implicit
-- build-in-place formal parameter of the given kind associated with the
-- function Func, and returns its Entity_Id. It is a bug if not found; the
-- caller should ensure this is called only when the extra formal exists.
function Build_Procedure_Body_Form
(Func_Id : Entity_Id; Func_Body : Node_Id) return Node_Id;
-- Create a procedure body which emulates the behavior of function Func_Id.
-- Func_Body is the root of the body of the function before its analysis.
-- The returned node is the root of the procedure body which will replace
-- the original function body, which is not needed for the C program.
function Is_Build_In_Place_Result_Type (Typ : Entity_Id) return Boolean;
-- Ada 2005 (AI-318-02): Returns True if functions returning the type use
-- build-in-place protocols. For inherently limited types, this must be
-- True in >= Ada 2005, and must be False in Ada 95. For other types, it
-- can be True or False, and the decision should be based on efficiency,
-- and should be the same for all language versions, so that mixed-dialect
-- programs will work.
--
-- For inherently limited types in Ada 2005, True means that calls will
-- actually be build-in-place in all cases. For other types, build-in-place
-- will be used when possible, but we need to make a copy at the call site
-- in some cases, notably assignment statements.
function Is_Build_In_Place_Function (E : Entity_Id) return Boolean;
-- Ada 2005 (AI-318-02): Returns True if E denotes a function, generic
-- function, or access-to-function type for which
-- Is_Build_In_Place_Result_Type is True. However, we never use
-- build-in-place if the convention is other than Ada, because that would
-- disturb mixed-language programs.
function Is_Build_In_Place_Function_Call (N : Node_Id) return Boolean;
-- Ada 2005 (AI-318-02): Returns True if N denotes a call to a function
-- that requires handling as a build-in-place call (possibly qualified or
-- converted).
function Is_Null_Procedure (Subp : Entity_Id) return Boolean;
-- Predicate to recognize stubbed procedures and null procedures, which
-- can be inlined unconditionally in all cases.
procedure Make_Build_In_Place_Call_In_Allocator
(Allocator : Node_Id;
Function_Call : Node_Id);
-- Ada 2005 (AI-318-02): Handle a call to a build-in-place function that
-- occurs as the expression initializing an allocator, by passing access
-- to the allocated object as an additional parameter of the function call.
-- A new access object is declared that is initialized to the result of the
-- allocator, passed to the function, and the allocator is rewritten to
-- refer to that access object. Function_Call must denote either an
-- N_Function_Call node for which Is_Build_In_Place_Call is True, or else
-- an N_Qualified_Expression node applied to such a function call.
procedure Make_Build_In_Place_Call_In_Anonymous_Context
(Function_Call : Node_Id);
-- Ada 2005 (AI-318-02): Handle a call to a build-in-place function that
-- occurs in a context that does not provide a separate object. A temporary
-- object is created to act as the return object and an access to the
-- temporary is passed as an additional parameter of the call. This occurs
-- in contexts such as subprogram call actuals and object renamings.
-- Function_Call must denote either an N_Function_Call node for which
-- Is_Build_In_Place_Call is True, or else an N_Qualified_Expression node
-- applied to such a function call.
procedure Make_Build_In_Place_Call_In_Assignment
(Assign : Node_Id;
Function_Call : Node_Id);
-- Ada 2005 (AI-318-02): Handle a call to a build-in-place function that
-- occurs as the right-hand side of an assignment statement by passing
-- access to the left-hand side as an additional parameter of the function
-- call. Assign must denote a N_Assignment_Statement. Function_Call must
-- denote either an N_Function_Call node for which Is_Build_In_Place_Call
-- is True, or an N_Qualified_Expression node applied to such a function
-- call.
procedure Make_Build_In_Place_Call_In_Object_Declaration
(Obj_Decl : Node_Id;
Function_Call : Node_Id);
-- Ada 2005 (AI-318-02): Handle a call to a build-in-place function that
-- occurs as the expression initializing an object declaration by
-- passing access to the declared object as an additional parameter of the
-- function call. Function_Call must denote either an N_Function_Call node
-- for which Is_Build_In_Place_Call is True, or an N_Qualified_Expression
-- node applied to such a function call.
procedure Make_Build_In_Place_Iface_Call_In_Allocator
(Allocator : Node_Id;
Function_Call : Node_Id);
-- Ada 2005 (AI-318-02): Handle a call to a build-in-place function that
-- occurs as the expression initializing an allocator, by passing access
-- to the allocated object as an additional parameter of the function call.
-- Function_Call must denote an expression containing a BIP function call
-- and an enclosing call to Ada.Tags.Displace to displace the pointer to
-- the returned BIP object to reference the secondary dispatch table of
-- an interface.
procedure Make_Build_In_Place_Iface_Call_In_Anonymous_Context
(Function_Call : Node_Id);
-- Ada 2005 (AI-318-02): Handle a call to a build-in-place function that
-- occurs in a context that does not provide a separate object. A temporary
-- object is created to act as the return object and an access to the
-- temporary is passed as an additional parameter of the call. This occurs
-- in contexts such as subprogram call actuals and object renamings.
-- Function_Call must denote an expression containing a BIP function call
-- and an enclosing call to Ada.Tags.Displace to displace the pointer to
-- the returned BIP object to reference the secondary dispatch table of
-- an interface.
procedure Make_Build_In_Place_Iface_Call_In_Object_Declaration
(Obj_Decl : Node_Id;
Function_Call : Node_Id);
-- Ada 2005 (AI-318-02): Handle a call to a build-in-place function that
-- occurs as the expression initializing an object declaration by passing
-- access to the declared object as an additional parameter of the function
-- call. Function_Call must denote an expression containing a BIP function
-- call and an enclosing call to Ada.Tags.Displace to displace the pointer
-- to the returned BIP object to reference the secondary dispatch table of
-- an interface.
procedure Make_CPP_Constructor_Call_In_Allocator
(Allocator : Node_Id;
Function_Call : Node_Id);
-- Handle a call to a CPP constructor that occurs as the expression that
-- initializes an allocator, by passing access to the allocated object as
-- an additional parameter of the constructor call. A new access object is
-- declared that is initialized to the result of the allocator, passed to
-- the constructor, and the allocator is rewritten to refer to that access
-- object. Function_Call must denote a call to a CPP_Constructor function.
function Needs_BIP_Alloc_Form (Func_Id : Entity_Id) return Boolean;
-- Ada 2005 (AI-318-02): Return True if the function needs an implicit
-- BIP_Alloc_Form parameter (see type BIP_Formal_Kind).
function Needs_BIP_Finalization_Master (Func_Id : Entity_Id) return Boolean;
-- Ada 2005 (AI-318-02): Return True if the result subtype of function
-- Func_Id might need finalization actions. This includes build-in-place
-- functions with tagged result types, since they can be invoked via
-- dispatching calls, and descendant types may require finalization.
function Needs_Result_Accessibility_Level
(Func_Id : Entity_Id) return Boolean;
-- Ada 2012 (AI05-0234): Return True if the function needs an implicit
-- parameter to identify the accessibility level of the function result
-- "determined by the point of call".
function Unqual_BIP_Iface_Function_Call (Expr : Node_Id) return Node_Id;
-- Return the inner BIP function call removing any qualification from Expr
-- including qualified expressions, type conversions, references, unchecked
-- conversions and calls to displace the pointer to the object, if Expr is
-- an expression containing a call displacing the pointer to the BIP object
-- to reference the secondary dispatch table of an interface; otherwise
-- return Empty.
end Exp_Ch6;
|
