1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2014, 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 -- Pragma handling is isolated in a separate package
27 -- (logically this processing belongs in chapter 4)
29 with Namet
; use Namet
;
31 with Snames
; use Snames
;
32 with Types
; use Types
;
36 -- The following table lists all pragmas that act as an assertion
39 Assertion_Expression_Pragma
: constant array (Pragma_Id
) of Boolean :=
40 (Pragma_Assert
=> True,
41 Pragma_Assert_And_Cut
=> True,
42 Pragma_Assume
=> True,
44 Pragma_Contract_Cases
=> True,
45 Pragma_Initial_Condition
=> True,
46 Pragma_Invariant
=> True,
47 Pragma_Loop_Invariant
=> True,
48 Pragma_Loop_Variant
=> True,
50 Pragma_Post_Class
=> True,
51 Pragma_Postcondition
=> True,
53 Pragma_Pre_Class
=> True,
54 Pragma_Precondition
=> True,
55 Pragma_Predicate
=> True,
56 Pragma_Refined_Post
=> True,
57 Pragma_Test_Case
=> True,
58 Pragma_Type_Invariant
=> True,
59 Pragma_Type_Invariant_Class
=> True,
62 -- The following table lists all the implementation-defined pragmas that
63 -- may apply to a body stub (no language defined pragmas apply). The table
64 -- should be synchronized with Aspect_On_Body_Or_Stub_OK in unit Aspects if
65 -- the pragmas below implement an aspect.
67 Pragma_On_Body_Or_Stub_OK
: constant array (Pragma_Id
) of Boolean :=
68 (Pragma_Refined_Depends
=> True,
69 Pragma_Refined_Global
=> True,
70 Pragma_Refined_Post
=> True,
71 Pragma_SPARK_Mode
=> True,
72 Pragma_Warnings
=> True,
79 procedure Analyze_Pragma
(N
: Node_Id
);
80 -- Analyze procedure for pragma reference node N
82 procedure Analyze_Contract_Cases_In_Decl_Part
(N
: Node_Id
);
83 -- Perform full analysis and expansion of delayed pragma Contract_Cases
85 procedure Analyze_Depends_In_Decl_Part
(N
: Node_Id
);
86 -- Perform full analysis of delayed pragma Depends. This routine is also
87 -- capable of performing basic analysis of pragma Refined_Depends.
89 procedure Analyze_External_Property_In_Decl_Part
91 Expr_Val
: out Boolean);
92 -- Perform full analysis of delayed pragmas Async_Readers, Async_Writers,
93 -- Effective_Reads and Effective_Writes. Flag Expr_Val contains the Boolean
94 -- argument of the pragma or a default True if no argument is present.
96 procedure Analyze_Global_In_Decl_Part
(N
: Node_Id
);
97 -- Perform full analysis of delayed pragma Global. This routine is also
98 -- capable of performing basic analysis of pragma Refind_Global.
100 procedure Analyze_Initial_Condition_In_Decl_Part
(N
: Node_Id
);
101 -- Perform full analysis of delayed pragma Initial_Condition
103 procedure Analyze_Initializes_In_Decl_Part
(N
: Node_Id
);
104 -- Perform full analysis of delayed pragma Initializes
106 procedure Analyze_Pre_Post_Condition_In_Decl_Part
108 Subp_Id
: Entity_Id
);
109 -- Perform preanalysis of a [refined] precondition or postcondition that
110 -- appears on a subprogram declaration or body [stub]. Prag denotes the
111 -- pragma, Subp_Id is the entity of the related subprogram. The preanalysis
112 -- of the expression is done as "spec expression" (see section "Handling
113 -- of Default and Per-Object Expressions in Sem).
115 procedure Analyze_Refined_Depends_In_Decl_Part
(N
: Node_Id
);
116 -- Preform full analysis of delayed pragma Refined_Depends. This routine
117 -- uses Analyze_Depends_In_Decl_Part as a starting point, then performs
118 -- various consistency checks between Depends and Refined_Depends.
120 procedure Analyze_Refined_Global_In_Decl_Part
(N
: Node_Id
);
121 -- Perform full analysis of delayed pragma Refined_Global. This routine
122 -- uses Analyze_Global_In_Decl_Part as a starting point, then performs
123 -- various consistency checks between Global and Refined_Global.
125 procedure Analyze_Refined_State_In_Decl_Part
(N
: Node_Id
);
126 -- Perform full analysis of delayed pragma Refined_State
128 procedure Analyze_Test_Case_In_Decl_Part
(N
: Node_Id
; S
: Entity_Id
);
129 -- Perform preanalysis of pragma Test_Case that applies to a subprogram
130 -- declaration. Parameter N denotes the pragma, S is the entity of the
131 -- related subprogram. The preanalysis of the expression is done as "spec
132 -- expression" (see section "Handling of Default and Per-Object Expressions
135 procedure Check_Applicable_Policy
(N
: Node_Id
);
136 -- N is either an N_Aspect or an N_Pragma node. There are two cases. If
137 -- the name of the aspect or pragma is not one of those recognized as
138 -- an assertion kind by an Assertion_Policy pragma, then the call has
139 -- no effect. Note that in the case of a pragma derived from an aspect,
140 -- the name we use for the purpose of this procedure is the aspect name,
141 -- which may be different from the pragma name (e.g. Precondition for
142 -- Pre aspect). In addition, 'Class aspects are recognized (and the
143 -- corresponding special names used in the processing).
145 -- If the name is a valid assertion kind name, then the Check_Policy pragma
146 -- chain is checked for a matching entry (or for an Assertion entry which
147 -- matches all possibilities). If a matching entry is found then the policy
148 -- is checked. If it is On or Check, then the Is_Checked flag is set in
149 -- the aspect or pragma node. If it is Off, Ignore, or Disable, then the
150 -- Is_Ignored flag is set in the aspect or pragma node. Additionally for
151 -- policy Disable, the Is_Disabled flag is set.
153 -- If no matching Check_Policy pragma is found then the effect depends on
154 -- whether -gnata was used, if so, then the call has no effect, otherwise
155 -- Is_Ignored (but not Is_Disabled) is set True.
157 procedure Check_External_Properties
163 -- Flags AR, AW, ER and EW denote the static values of external properties
164 -- Async_Readers, Async_Writers, Effective_Reads and Effective_Writes. Item
165 -- is the related variable or state. Ensure legality of the combination and
166 -- issue an error for an illegal combination.
168 procedure Check_Missing_Part_Of
(Item_Id
: Entity_Id
);
169 -- Determine whether the placement within the state space of an abstract
170 -- state, variable or package instantiation denoted by Item_Id requires the
171 -- use of indicator/option Part_Of. If this is the case, emit an error.
173 procedure Collect_Subprogram_Inputs_Outputs
174 (Subp_Id
: Entity_Id
;
175 Subp_Inputs
: in out Elist_Id
;
176 Subp_Outputs
: in out Elist_Id
;
177 Global_Seen
: out Boolean);
178 -- Used during the analysis of pragmas Depends, Global, Refined_Depends,
179 -- and Refined_Global. Also used by GNATprove. Gathers all inputs and
180 -- outputs of subprogram Subp_Id in lists Subp_Inputs and Subp_Outputs.
181 -- If subprogram has no inputs and/or outputs, then the returned list
182 -- is No_Elist. Global_Seen is set when the related subprogram has
183 -- pragma [Refined_]Global.
185 function Delay_Config_Pragma_Analyze
(N
: Node_Id
) return Boolean;
186 -- N is a pragma appearing in a configuration pragma file. Most such
187 -- pragmas are analyzed when the file is read, before parsing and analyzing
188 -- the main unit. However, the analysis of certain pragmas results in
189 -- adding information to the compiled main unit, and this cannot be done
190 -- till the main unit is processed. Such pragmas return True from this
191 -- function and in Frontend pragmas where Delay_Config_Pragma_Analyze is
192 -- True have their analysis delayed until after the main program is parsed
195 function Get_SPARK_Mode_From_Pragma
(N
: Node_Id
) return SPARK_Mode_Type
;
196 -- Given a pragma SPARK_Mode node, return corresponding mode id
198 procedure Initialize
;
199 -- Initializes data structures used for pragma processing. Must be called
200 -- before analyzing each new main source program.
202 function Is_Config_Static_String
(Arg
: Node_Id
) return Boolean;
203 -- This is called for a configuration pragma that requires either string
204 -- literal or a concatenation of string literals. We cannot use normal
205 -- static string processing because it is too early in the case of the
206 -- pragma appearing in a configuration pragmas file. If Arg is of an
207 -- appropriate form, then this call obtains the string (doing any necessary
208 -- concatenations) and places it in Name_Buffer, setting Name_Len to its
209 -- length, and then returns True. If it is not of the correct form, then an
210 -- appropriate error message is posted, and False is returned.
212 function Is_Elaboration_SPARK_Mode
(N
: Node_Id
) return Boolean;
213 -- Determine whether pragma SPARK_Mode appears in the statement part of a
216 function Is_Non_Significant_Pragma_Reference
(N
: Node_Id
) return Boolean;
217 -- The node N is a node for an entity and the issue is whether the
218 -- occurrence is a reference for the purposes of giving warnings about
219 -- unreferenced variables. This function returns True if the reference is
220 -- not a reference from this point of view (e.g. the occurrence in a pragma
221 -- Pack) and False if it is a real reference (e.g. the occurrence in a
224 function Is_Pragma_String_Literal
(Par
: Node_Id
) return Boolean;
225 -- Given an N_Pragma_Argument_Association node, Par, which has the form of
226 -- an operator symbol, determines whether or not it should be treated as an
227 -- string literal. This is called by Sem_Ch6.Analyze_Operator_Symbol. If
228 -- True is returned, the argument is converted to a string literal. If
229 -- False is returned, then the argument is treated as an entity reference
232 function Is_Private_SPARK_Mode
(N
: Node_Id
) return Boolean;
233 -- Determine whether pragma SPARK_Mode appears in the private part of a
236 function Is_Valid_Assertion_Kind
(Nam
: Name_Id
) return Boolean;
237 -- Returns True if Nam is one of the names recognized as a valid assertion
238 -- kind by the Assertion_Policy pragma. Note that the 'Class cases are
239 -- represented by the corresponding special names Name_uPre, Name_uPost,
240 -- Name_uInviarnat, and Name_uType_Invariant (_Pre, _Post, _Invariant,
241 -- and _Type_Invariant).
243 procedure Make_Aspect_For_PPC_In_Gen_Sub_Decl
(Decl
: Node_Id
);
244 -- This routine makes aspects from precondition or postcondition pragmas
245 -- that appear within a generic subprogram declaration. Decl is the generic
246 -- subprogram declaration node. Note that the aspects are attached to the
247 -- generic copy and also to the orginal tree.
249 procedure Process_Compilation_Unit_Pragmas
(N
: Node_Id
);
250 -- Called at the start of processing compilation unit N to deal with any
251 -- special issues regarding pragmas. In particular, we have to deal with
252 -- Suppress_All at this stage, since it can appear after the unit instead
253 -- of before (actually we allow it to appear anywhere).
255 procedure Relocate_Pragmas_To_Body
256 (Subp_Body
: Node_Id
;
257 Target_Body
: Node_Id
:= Empty
);
258 -- Resocate all pragmas that follow and apply to subprogram body Subp_Body
259 -- to its own declaration list. Candidate pragmas are classified in table
260 -- Pragma_On_Body_Or_Stub_OK. If Target_Body is set, the pragma are moved
261 -- to the declarations of Target_Body. This formal should be set when
262 -- dealing with subprogram body stubs or expression functions.
264 procedure Set_Encoded_Interface_Name
(E
: Entity_Id
; S
: Node_Id
);
265 -- This routine is used to set an encoded interface name. The node S is
266 -- an N_String_Literal node for the external name to be set, and E is an
267 -- entity whose Interface_Name field is to be set. In the normal case where
268 -- S contains a name that is a valid C identifier, then S is simply set as
269 -- the value of the Interface_Name. Otherwise it is encoded as needed by
270 -- particular operating systems. See the body for details of the encoding.