gcc/ada/contracts.ads

   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) 2015-2020, 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
  29 with Types; use Types;
  30
  31 package 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, task unit, or type denoted by Id.
  37    --  The following are 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    --    No_Caching
  54    --    Part_Of
  55    --    Postcondition
  56    --    Precondition
  57    --    Refined_Depends
  58    --    Refined_Global
  59    --    Refined_Post
  60    --    Refined_States
  61    --    Test_Case
  62    --    Volatile_Function
  63
  64    procedure Analyze_Contracts (L : List_Id);
  65    --  Analyze the contracts of all eligible constructs found in list L
  66
  67    procedure Analyze_Entry_Or_Subprogram_Body_Contract (Body_Id : Entity_Id);
  68    --  Analyze all delayed pragmas chained on the contract of entry or
  69    --  subprogram body Body_Id as if they appeared at the end of a declarative
  70    --  region. Pragmas in question are:
  71    --
  72    --    Contract_Cases     (stand alone subprogram body)
  73    --    Depends            (stand alone subprogram body)
  74    --    Global             (stand alone subprogram body)
  75    --    Postcondition      (stand alone subprogram body)
  76    --    Precondition       (stand alone subprogram body)
  77    --    Refined_Depends
  78    --    Refined_Global
  79    --    Refined_Post
  80    --    Subprogram_Variant (stand alone subprogram body)
  81    --    Test_Case          (stand alone subprogram body)
  82
  83    procedure Analyze_Entry_Or_Subprogram_Contract
  84      (Subp_Id   : Entity_Id;
  85       Freeze_Id : Entity_Id := Empty);
  86    --  Analyze all delayed pragmas chained on the contract of entry or
  87    --  subprogram Subp_Id as if they appeared at the end of a declarative
  88    --  region. The pragmas in question are:
  89    --
  90    --    Contract_Cases
  91    --    Depends
  92    --    Global
  93    --    Postcondition
  94    --    Precondition
  95    --    Subprogram_Variant
  96    --    Test_Case
  97    --
  98    --  Freeze_Id is the entity of a [generic] package body or a [generic]
  99    --  subprogram body which "freezes" the contract of Subp_Id.
 100
 101    procedure Analyze_Object_Contract
 102      (Obj_Id    : Entity_Id;
 103       Freeze_Id : Entity_Id := Empty);
 104    --  Analyze all delayed pragmas chained on the contract of object Obj_Id as
 105    --  if they appeared at the end of the declarative region. The pragmas to be
 106    --  considered are:
 107    --
 108    --    Async_Readers
 109    --    Async_Writers
 110    --    Depends           (single concurrent object)
 111    --    Effective_Reads
 112    --    Effective_Writes
 113    --    Global            (single concurrent object)
 114    --    Part_Of
 115    --
 116    --  Freeze_Id is the entity of a [generic] package body or a [generic]
 117    --  subprogram body which "freezes" the contract of Obj_Id.
 118
 119    procedure Analyze_Type_Contract (Type_Id : Entity_Id);
 120    --  Analyze all delayed pragmas chained on the contract of object Obj_Id as
 121    --  if they appeared at the end of the declarative region. The pragmas to be
 122    --  considered are:
 123    --
 124    --    Async_Readers
 125    --    Async_Writers
 126    --    Effective_Reads
 127    --    Effective_Writes
 128    --
 129    --  In the case of a protected or task type, there will also be
 130    --  a call to Analyze_Protected_Contract or Analyze_Task_Contract.
 131
 132    procedure Analyze_Package_Body_Contract
 133      (Body_Id   : Entity_Id;
 134       Freeze_Id : Entity_Id := Empty);
 135    --  Analyze all delayed pragmas chained on the contract of package body
 136    --  Body_Id as if they appeared at the end of a declarative region. The
 137    --  pragmas that are considered are:
 138    --
 139    --    Refined_State
 140    --
 141    --  Freeze_Id is the entity of a [generic] package body or a [generic]
 142    --  subprogram body which "freezes" the contract of Body_Id.
 143
 144    procedure Analyze_Package_Contract (Pack_Id : Entity_Id);
 145    --  Analyze all delayed pragmas chained on the contract of package Pack_Id
 146    --  as if they appeared at the end of a declarative region. The pragmas
 147    --  that are considered are:
 148    --
 149    --    Initial_Condition
 150    --    Initializes
 151
 152    procedure Analyze_Protected_Contract (Prot_Id : Entity_Id);
 153    --  Analyze all delayed pragmas chained on the contract of protected unit
 154    --  Prot_Id if they appeared at the end of a declarative region. Currently
 155    --  there are no such pragmas.
 156
 157    procedure Analyze_Subprogram_Body_Stub_Contract (Stub_Id : Entity_Id);
 158    --  Analyze all delayed pragmas chained on the contract of subprogram body
 159    --  stub Stub_Id as if they appeared at the end of a declarative region. The
 160    --  pragmas in question are:
 161    --
 162    --    Contract_Cases
 163    --    Depends
 164    --    Global
 165    --    Postcondition
 166    --    Precondition
 167    --    Refined_Depends
 168    --    Refined_Global
 169    --    Refined_Post
 170    --    Test_Case
 171
 172    procedure Analyze_Task_Contract (Task_Id : Entity_Id);
 173    --  Analyze all delayed pragmas chained on the contract of task unit Task_Id
 174    --  as if they appeared at the end of a declarative region. The pragmas in
 175    --  question are:
 176    --
 177    --    Depends
 178    --    Global
 179
 180    procedure Create_Generic_Contract (Unit : Node_Id);
 181    --  Create a contract node for a generic package, generic subprogram, or a
 182    --  generic body denoted by Unit by collecting all source contract-related
 183    --  pragmas in the contract of the unit.
 184
 185    procedure Freeze_Previous_Contracts (Body_Decl : Node_Id);
 186    --  Freeze the contracts of all source constructs found in the declarative
 187    --  list which contains entry, package, protected, subprogram, or task body
 188    --  denoted by Body_Decl. In addition, freeze the contract of the nearest
 189    --  enclosing package body.
 190
 191    function Get_Postcond_Enabled (Subp : Entity_Id) return Entity_Id;
 192    --  Get the defining identifier for a subprogram's Postcond_Enabled
 193    --  object created during the expansion of the subprogram's postconditions.
 194
 195    function Get_Result_Object_For_Postcond (Subp : Entity_Id) return Entity_Id;
 196    --  Get the defining identifier for a subprogram's
 197    --  Result_Object_For_Postcond object created during the expansion of the
 198    --  subprogram's postconditions.
 199
 200    function Get_Return_Success_For_Postcond
 201      (Subp : Entity_Id) return Entity_Id;
 202    --  Get the defining identifier for a subprogram's
 203    --  Return_Success_For_Postcond object created during the expansion of the
 204    --  subprogram's postconditions.
 205
 206    procedure Inherit_Subprogram_Contract
 207      (Subp      : Entity_Id;
 208       From_Subp : Entity_Id);
 209    --  Inherit relevant contract items from source subprogram From_Subp. Subp
 210    --  denotes the destination subprogram. The inherited items are:
 211    --    Extensions_Visible
 212    --  ??? it would be nice if this routine handles Pre'Class and Post'Class
 213
 214    procedure Instantiate_Subprogram_Contract (Templ : Node_Id; L : List_Id);
 215    --  Instantiate all source pragmas found in the contract of the generic
 216    --  subprogram declaration template denoted by Templ. The instantiated
 217    --  pragmas are added to list L.
 218
 219    procedure Save_Global_References_In_Contract
 220      (Templ  : Node_Id;
 221       Gen_Id : Entity_Id);
 222    --  Save all global references found within the aspect specifications and
 223    --  the contract-related source pragmas assocated with generic template
 224    --  Templ. Gen_Id denotes the entity of the analyzed generic copy.
 225
 226 end Contracts;