1------------------------------------------------------------------------------ 2-- -- 3-- GNAT COMPILER COMPONENTS -- 4-- -- 5-- S E M _ C H 1 2 -- 6-- -- 7-- S p e c -- 8-- -- 9-- Copyright (C) 1992-2019, 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 26with Inline; use Inline; 27with Types; use Types; 28 29package Sem_Ch12 is 30 procedure Analyze_Generic_Package_Declaration (N : Node_Id); 31 procedure Analyze_Generic_Subprogram_Declaration (N : Node_Id); 32 procedure Analyze_Package_Instantiation (N : Node_Id); 33 procedure Analyze_Procedure_Instantiation (N : Node_Id); 34 procedure Analyze_Function_Instantiation (N : Node_Id); 35 procedure Analyze_Formal_Object_Declaration (N : Node_Id); 36 procedure Analyze_Formal_Type_Declaration (N : Node_Id); 37 procedure Analyze_Formal_Subprogram_Declaration (N : Node_Id); 38 procedure Analyze_Formal_Package_Declaration (N : Node_Id); 39 40 procedure Add_Pending_Instantiation (Inst : Node_Id; Act_Decl : Node_Id); 41 -- Add an entry in the table of instance bodies that must be analyzed 42 -- when inlining requires its body or the body of a nested instance. 43 44 function Build_Function_Wrapper 45 (Formal_Subp : Entity_Id; 46 Actual_Subp : Entity_Id) return Node_Id; 47 -- In GNATprove mode, create a wrapper function for actuals that are 48 -- functions with any number of formal parameters, in order to propagate 49 -- their contract to the renaming declarations generated for them. This 50 -- is called after the renaming declaration created for the formal in the 51 -- instance has been analyzed, and the actual is known. 52 53 function Build_Operator_Wrapper 54 (Formal_Subp : Entity_Id; 55 Actual_Subp : Entity_Id) return Node_Id; 56 -- In GNATprove mode, create a wrapper function for actuals that are 57 -- operators, in order to propagate their contract to the renaming 58 -- declarations generated for them. The types are (the instances of) 59 -- the types of the formal subprogram. 60 61 procedure Start_Generic; 62 -- Must be invoked before starting to process a generic spec or body 63 64 procedure End_Generic; 65 -- Must be invoked just at the end of the end of the processing of a 66 -- generic spec or body. 67 68 procedure Check_Generic_Child_Unit 69 (Gen_Id : Node_Id; 70 Parent_Installed : in out Boolean); 71 -- If the name of the generic unit in an instantiation or a renaming is a 72 -- selected component, then the prefix may be an instance and the selector 73 -- may designate a child unit. Retrieve the parent generic and search for 74 -- the child unit that must be declared within. Similarly, if this is the 75 -- name of a generic child unit within an instantiation of its own parent, 76 -- retrieve the parent generic. If the parent is installed as a result of 77 -- this call, then Parent_Installed is set True, otherwise Parent_Installed 78 -- is unchanged by the call. 79 80 function Copy_Generic_Node 81 (N : Node_Id; 82 Parent_Id : Node_Id; 83 Instantiating : Boolean) return Node_Id; 84 -- Copy the tree for a generic unit or its body. The unit is copied 85 -- repeatedly: once to produce a copy on which semantic analysis of 86 -- the generic is performed, and once for each instantiation. The tree 87 -- being copied is not semantically analyzed, except that references to 88 -- global entities are marked on terminal nodes. Note that this function 89 -- copies any aspect specifications from the input node N to the returned 90 -- node, as well as the setting of the Has_Aspects flag. 91 92 function Get_Instance_Of (A : Entity_Id) return Entity_Id; 93 -- Retrieve actual associated with given generic parameter. 94 -- If A is uninstantiated or not a generic parameter, return A. 95 96 function Get_Unit_Instantiation_Node (A : Entity_Id) return Node_Id; 97 -- Given the entity of a unit that is an instantiation, retrieve the 98 -- original instance node. This is used when loading the instantiations 99 -- of the ancestors of a child generic that is being instantiated. 100 101 procedure Instantiate_Package_Body 102 (Body_Info : Pending_Body_Info; 103 Inlined_Body : Boolean := False; 104 Body_Optional : Boolean := False); 105 -- Called after semantic analysis, to complete the instantiation of 106 -- package instances. The flag Inlined_Body is set if the body is 107 -- being instantiated on the fly for inlining purposes. 108 -- 109 -- The flag Body_Optional indicates that the call is for an instance 110 -- that precedes the current instance in the same declarative part. 111 -- This call is needed when instantiating a nested generic whose body 112 -- is to be found in the body of an instance. Normally we instantiate 113 -- package bodies only when they appear in the main unit, or when their 114 -- contents are needed for a nested generic G. If unit U contains several 115 -- instances I1, I2, etc. and I2 contains a nested generic, then when U 116 -- appears in the context of some other unit P that contains an instance 117 -- of G, we compile the body of I2, but not that of I1. However, when we 118 -- compile U as the main unit, we compile both bodies. This will lead to 119 -- link-time errors if the compilation of I1 generates public symbols, 120 -- because those in I2 will receive different names in both cases. This 121 -- forces us to analyze the body of I1 even when U is not the main unit. 122 -- We don't want this additional mechanism to generate an error when the 123 -- body of the generic for I1 is not present, and this is the reason for 124 -- the presence of the flag Body_Optional, which is exchanged between the 125 -- current procedure and Load_Parent_Of_Generic. 126 127 procedure Instantiate_Subprogram_Body 128 (Body_Info : Pending_Body_Info; 129 Body_Optional : Boolean := False); 130 -- Called after semantic analysis, to complete the instantiation of 131 -- function and procedure instances. The flag Body_Optional has the 132 -- same purpose as described for Instantiate_Package_Body. 133 134 function Need_Subprogram_Instance_Body 135 (N : Node_Id; 136 Subp : Entity_Id) return Boolean; 137 -- If a subprogram instance is inlined, indicate that the body of it 138 -- must be created, to be used in inlined calls by the back-end. The 139 -- subprogram may be inlined because the generic itself carries the 140 -- pragma, or because a pragma appears for the instance in the scope. 141 -- of the instance. 142 143 procedure Save_Global_References (Templ : Node_Id); 144 -- Traverse the original generic unit, and capture all references to 145 -- entities that are defined outside of the generic in the analyzed tree 146 -- for the template. These references are copied into the original tree, 147 -- so that they appear automatically in every instantiation. A critical 148 -- invariant in this approach is that if an id in the generic resolves to 149 -- a local entity, the corresponding id in the instance will resolve to 150 -- the homologous entity in the instance, even though the enclosing context 151 -- for resolution is different, as long as the global references have been 152 -- captured as described here. 153 154 -- Because instantiations can be nested, the environment of the instance, 155 -- involving the actuals and other data-structures, must be saved and 156 -- restored in stack-like fashion. Front-end inlining also uses these 157 -- structures for the management of private/full views. 158 159 procedure Save_Global_References_In_Aspects (N : Node_Id); 160 -- Save all global references found within the expressions of all aspects 161 -- that appear on node N. 162 163 procedure Set_Copied_Sloc_For_Inlined_Body (N : Node_Id; E : Entity_Id); 164 -- This procedure is used when a subprogram body is inlined. This process 165 -- shares the same circuitry as the creation of an instantiated copy of 166 -- a generic template. The call to this procedure establishes a new source 167 -- file entry representing the inlined body as an instantiation, marked as 168 -- an inlined body (so that errout can distinguish cases for generating 169 -- error messages, otherwise the treatment is identical). In this call 170 -- N is the subprogram body and E is the defining identifier of the 171 -- subprogram in question. The resulting Sloc adjustment factor is 172 -- saved as part of the internal state of the Sem_Ch12 package for use 173 -- in subsequent calls to copy nodes. 174 175 procedure Set_Copied_Sloc_For_Inherited_Pragma 176 (N : Node_Id; 177 E : Entity_Id); 178 -- This procedure is used when a class-wide pre- or postcondition is 179 -- inherited. This process shares the same circuitry as the creation of 180 -- an instantiated copy of a generic template. The call to this procedure 181 -- establishes a new source file entry representing the inherited pragma 182 -- as an instantiation, marked as an inherited pragma (so that errout can 183 -- distinguish cases for generating error messages, otherwise the treatment 184 -- is identical). In this call, N is the subprogram declaration from 185 -- which the pragma is inherited and E is the defining identifier of 186 -- the overriding subprogram (when the subprogram is redefined) or the 187 -- defining identifier of the extension type (when the subprogram is 188 -- inherited). The resulting Sloc adjustment factor is saved as part of the 189 -- internal state of the Sem_Ch12 package for use in subsequent calls to 190 -- copy nodes. 191 192 procedure Adjust_Inherited_Pragma_Sloc (N : Node_Id); 193 -- This procedure is used when a class-wide pre- or postcondition 194 -- is inherited. It is called on each node of the pragma expression 195 -- to adjust its sloc. These call should be preceded by a call to 196 -- Set_Copied_Sloc_For_Inherited_Pragma that sets the required sloc 197 -- adjustment. This is done directly, instead of using Copy_Generic_Node 198 -- to copy nodes and adjust slocs, as Copy_Generic_Node expects a specific 199 -- structure to be in place, which is not the case for inherited pragmas. 200 201 procedure Save_Env 202 (Gen_Unit : Entity_Id; 203 Act_Unit : Entity_Id); 204 -- Because instantiations can be nested, the compiler maintains a stack 205 -- of environments that holds variables relevant to the current instance: 206 -- most importanty Instantiated_Parent, Exchanged_Views, Hidden_Entities, 207 -- and others (see full list in Instance_Env). 208 209 procedure Restore_Env; 210 -- After processing an instantiation, or aborting one because of semantic 211 -- errors, remove the current Instantiation_Env from Instantation_Envs. 212 213 procedure Initialize; 214 -- Initializes internal data structures 215 216 procedure Check_Private_View (N : Node_Id); 217 -- Check whether the type of a generic entity has a different view between 218 -- the point of generic analysis and the point of instantiation. If the 219 -- view has changed, then at the point of instantiation we restore the 220 -- correct view to perform semantic analysis of the instance, and reset 221 -- the current view after instantiation. The processing is driven by the 222 -- current private status of the type of the node, and Has_Private_View, 223 -- a flag that is set at the point of generic compilation. If view and 224 -- flag are inconsistent then the type is updated appropriately. 225 -- 226 -- This subprogram is used in Check_Generic_Actuals and Copy_Generic_Node, 227 -- and is exported here for the purpose of front-end inlining (see Exp_Ch6. 228 -- Expand_Inlined_Call.Process_Formals). 229 230end Sem_Ch12; 231