1------------------------------------------------------------------------------
2--                                                                          --
3--                         GNAT COMPILER COMPONENTS                         --
4--                                                                          --
5--                            C O N T R A C T S                             --
6--                                                                          --
7--                                 S p e c                                  --
8--                                                                          --
9--          Copyright (C) 2015-2019, 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------------------------------------------------------------------------------
25
26--  This package contains routines that perform analysis and expansion of
27--  various contracts.
28
29with Types; use Types;
30
31package Contracts is
32
33   procedure Add_Contract_Item (Prag : Node_Id; Id : Entity_Id);
34   --  Add pragma Prag to the contract of a constant, entry, entry family,
35   --  [generic] package, package body, protected unit, [generic] subprogram,
36   --  subprogram body, variable or task unit denoted by Id. The following are
37   --  valid pragmas:
38   --
39   --    Abstract_State
40   --    Async_Readers
41   --    Async_Writers
42   --    Attach_Handler
43   --    Constant_After_Elaboration
44   --    Contract_Cases
45   --    Depends
46   --    Effective_Reads
47   --    Effective_Writes
48   --    Extensions_Visible
49   --    Global
50   --    Initial_Condition
51   --    Initializes
52   --    Interrupt_Handler
53   --    Part_Of
54   --    Postcondition
55   --    Precondition
56   --    Refined_Depends
57   --    Refined_Global
58   --    Refined_Post
59   --    Refined_States
60   --    Test_Case
61   --    Volatile_Function
62
63   procedure Analyze_Contracts (L : List_Id);
64   --  Analyze the contracts of all eligible constructs found in list L
65
66   procedure Analyze_Entry_Or_Subprogram_Body_Contract (Body_Id : Entity_Id);
67   --  Analyze all delayed pragmas chained on the contract of entry or
68   --  subprogram body Body_Id as if they appeared at the end of a declarative
69   --  region. Pragmas in question are:
70   --
71   --    Contract_Cases   (stand alone subprogram body)
72   --    Depends          (stand alone subprogram body)
73   --    Global           (stand alone subprogram body)
74   --    Postcondition    (stand alone subprogram body)
75   --    Precondition     (stand alone subprogram body)
76   --    Refined_Depends
77   --    Refined_Global
78   --    Refined_Post
79   --    Test_Case        (stand alone subprogram body)
80
81   procedure Analyze_Entry_Or_Subprogram_Contract
82     (Subp_Id   : Entity_Id;
83      Freeze_Id : Entity_Id := Empty);
84   --  Analyze all delayed pragmas chained on the contract of entry or
85   --  subprogram Subp_Id as if they appeared at the end of a declarative
86   --  region. The pragmas in question are:
87   --
88   --    Contract_Cases
89   --    Depends
90   --    Global
91   --    Postcondition
92   --    Precondition
93   --    Test_Case
94   --
95   --  Freeze_Id is the entity of a [generic] package body or a [generic]
96   --  subprogram body which "freezes" the contract of Subp_Id.
97
98   procedure Analyze_Object_Contract
99     (Obj_Id    : Entity_Id;
100      Freeze_Id : Entity_Id := Empty);
101   --  Analyze all delayed pragmas chained on the contract of object Obj_Id as
102   --  if they appeared at the end of the declarative region. The pragmas to be
103   --  considered are:
104   --
105   --    Async_Readers
106   --    Async_Writers
107   --    Depends           (single concurrent object)
108   --    Effective_Reads
109   --    Effective_Writes
110   --    Global            (single concurrent object)
111   --    Part_Of
112   --
113   --  Freeze_Id is the entity of a [generic] package body or a [generic]
114   --  subprogram body which "freezes" the contract of Obj_Id.
115
116   procedure Analyze_Package_Body_Contract
117     (Body_Id   : Entity_Id;
118      Freeze_Id : Entity_Id := Empty);
119   --  Analyze all delayed pragmas chained on the contract of package body
120   --  Body_Id as if they appeared at the end of a declarative region. The
121   --  pragmas that are considered are:
122   --
123   --    Refined_State
124   --
125   --  Freeze_Id is the entity of a [generic] package body or a [generic]
126   --  subprogram body which "freezes" the contract of Body_Id.
127
128   procedure Analyze_Package_Contract (Pack_Id : Entity_Id);
129   --  Analyze all delayed pragmas chained on the contract of package Pack_Id
130   --  as if they appeared at the end of a declarative region. The pragmas
131   --  that are considered are:
132   --
133   --    Initial_Condition
134   --    Initializes
135
136   procedure Analyze_Protected_Contract (Prot_Id : Entity_Id);
137   --  Analyze all delayed pragmas chained on the contract of protected unit
138   --  Prot_Id if they appeared at the end of a declarative region. Currently
139   --  there are no such pragmas.
140
141   procedure Analyze_Subprogram_Body_Stub_Contract (Stub_Id : Entity_Id);
142   --  Analyze all delayed pragmas chained on the contract of subprogram body
143   --  stub Stub_Id as if they appeared at the end of a declarative region. The
144   --  pragmas in question are:
145   --
146   --    Contract_Cases
147   --    Depends
148   --    Global
149   --    Postcondition
150   --    Precondition
151   --    Refined_Depends
152   --    Refined_Global
153   --    Refined_Post
154   --    Test_Case
155
156   procedure Analyze_Task_Contract (Task_Id : Entity_Id);
157   --  Analyze all delayed pragmas chained on the contract of task unit Task_Id
158   --  as if they appeared at the end of a declarative region. The pragmas in
159   --  question are:
160   --
161   --    Depends
162   --    Global
163
164   procedure Create_Generic_Contract (Unit : Node_Id);
165   --  Create a contract node for a generic package, generic subprogram, or a
166   --  generic body denoted by Unit by collecting all source contract-related
167   --  pragmas in the contract of the unit.
168
169   procedure Freeze_Previous_Contracts (Body_Decl : Node_Id);
170   --  Freeze the contracts of all source constructs found in the declarative
171   --  list which contains entry, package, protected, subprogram, or task body
172   --  denoted by Body_Decl. In addition, freeze the contract of the nearest
173   --  enclosing package body.
174
175   procedure Inherit_Subprogram_Contract
176     (Subp      : Entity_Id;
177      From_Subp : Entity_Id);
178   --  Inherit relevant contract items from source subprogram From_Subp. Subp
179   --  denotes the destination subprogram. The inherited items are:
180   --    Extensions_Visible
181   --  ??? it would be nice if this routine handles Pre'Class and Post'Class
182
183   procedure Instantiate_Subprogram_Contract (Templ : Node_Id; L : List_Id);
184   --  Instantiate all source pragmas found in the contract of the generic
185   --  subprogram declaration template denoted by Templ. The instantiated
186   --  pragmas are added to list L.
187
188   procedure Save_Global_References_In_Contract
189     (Templ  : Node_Id;
190      Gen_Id : Entity_Id);
191   --  Save all global references found within the aspect specifications and
192   --  the contract-related source pragmas assocated with generic template
193   --  Templ. Gen_Id denotes the entity of the analyzed generic copy.
194
195end Contracts;
196