1------------------------------------------------------------------------------ 2-- -- 3-- GNAT COMPILER COMPONENTS -- 4-- -- 5-- E X P _ C H 6 -- 6-- -- 7-- S p e c -- 8-- -- 9-- Copyright (C) 1992-2021, 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-- Expand routines for chapter 6 constructs 27 28with Types; use Types; 29 30package Exp_Ch6 is 31 32 procedure Expand_N_Extended_Return_Statement (N : Node_Id); 33 procedure Expand_N_Function_Call (N : Node_Id); 34 procedure Expand_N_Procedure_Call_Statement (N : Node_Id); 35 procedure Expand_N_Return_When_Statement (N : Node_Id); 36 procedure Expand_N_Simple_Return_Statement (N : Node_Id); 37 procedure Expand_N_Subprogram_Body (N : Node_Id); 38 procedure Expand_N_Subprogram_Body_Stub (N : Node_Id); 39 procedure Expand_N_Subprogram_Declaration (N : Node_Id); 40 41 procedure Expand_Call (N : Node_Id); 42 -- This procedure contains common processing for Expand_N_Function_Call, 43 -- Expand_N_Procedure_Statement, and Expand_N_Entry_Call. 44 45 procedure Freeze_Subprogram (N : Node_Id); 46 -- generate the appropriate expansions related to Subprogram freeze 47 -- nodes (e.g. the filling of the corresponding Dispatch Table for 48 -- Primitive Operations) 49 50 -- The following type defines the various forms of allocation used for the 51 -- results of build-in-place function calls. 52 53 type BIP_Allocation_Form is 54 (Unspecified, 55 Caller_Allocation, 56 Secondary_Stack, 57 Global_Heap, 58 User_Storage_Pool); 59 60 type BIP_Formal_Kind is 61 -- Ada 2005 (AI-318-02): This type defines the kinds of implicit extra 62 -- formals created for build-in-place functions. The order of these 63 -- enumeration literals matches the order in which the formals are 64 -- declared. See Sem_Ch6.Create_Extra_Formals. 65 66 (BIP_Alloc_Form, 67 -- Present if result subtype is unconstrained or tagged. Indicates 68 -- whether the return object is allocated by the caller or callee, and 69 -- if the callee, whether to use the secondary stack or the heap. See 70 -- Create_Extra_Formals. 71 72 BIP_Storage_Pool, 73 -- Present if result subtype is unconstrained or tagged. If 74 -- BIP_Alloc_Form = User_Storage_Pool, this is a pointer to the pool 75 -- (of type access to Root_Storage_Pool'Class). Otherwise null. 76 77 BIP_Finalization_Master, 78 -- Present if result type needs finalization. Pointer to caller's 79 -- finalization master. 80 81 BIP_Task_Master, 82 -- Present if result type contains tasks. Master associated with 83 -- calling context. 84 85 BIP_Activation_Chain, 86 -- Present if result type contains tasks. Caller's activation chain 87 88 BIP_Object_Access); 89 -- Present for all build-in-place functions. Address at which to place 90 -- the return object, or null if BIP_Alloc_Form indicates allocated by 91 -- callee. 92 -- 93 -- ??? We might also need to be able to pass in a constrained flag. 94 95 procedure Add_Extra_Actual_To_Call 96 (Subprogram_Call : Node_Id; 97 Extra_Formal : Entity_Id; 98 Extra_Actual : Node_Id); 99 -- Adds Extra_Actual as a named parameter association for the formal 100 -- Extra_Formal in Subprogram_Call. 101 102 function BIP_Formal_Suffix (Kind : BIP_Formal_Kind) return String; 103 -- Ada 2005 (AI-318-02): Returns a string to be used as the suffix of names 104 -- for build-in-place formal parameters of the given kind. 105 106 function BIP_Suffix_Kind (E : Entity_Id) return BIP_Formal_Kind; 107 -- Ada 2005 (AI-318-02): Returns the kind of the given BIP extra formal. 108 109 function Build_In_Place_Formal 110 (Func : Entity_Id; 111 Kind : BIP_Formal_Kind) return Entity_Id; 112 -- Ada 2005 (AI-318-02): Locates and returns the entity for the implicit 113 -- build-in-place formal parameter of the given kind associated with the 114 -- function Func, and returns its Entity_Id. It is a bug if not found; the 115 -- caller should ensure this is called only when the extra formal exists. 116 117 function Build_Procedure_Body_Form 118 (Func_Id : Entity_Id; Func_Body : Node_Id) return Node_Id; 119 -- Create a procedure body which emulates the behavior of function Func_Id. 120 -- Func_Body is the root of the body of the function before its analysis. 121 -- The returned node is the root of the procedure body which will replace 122 -- the original function body, which is not needed for the C program. 123 124 procedure Install_Class_Preconditions_Check (Call_Node : Node_Id); 125 -- Install check of class-wide preconditions on the caller. 126 127 function Is_Build_In_Place_Entity (E : Entity_Id) return Boolean; 128 -- Ada 2005 (AI-318-02): Returns True if E is a BIP entity. 129 130 function Is_Build_In_Place_Result_Type (Typ : Entity_Id) return Boolean; 131 -- Ada 2005 (AI-318-02): Returns True if functions returning the type use 132 -- build-in-place protocols. For inherently limited types, this must be 133 -- True in >= Ada 2005, and must be False in Ada 95. For other types, it 134 -- can be True or False, and the decision should be based on efficiency, 135 -- and should be the same for all language versions, so that mixed-dialect 136 -- programs will work. 137 -- 138 -- For inherently limited types in Ada 2005, True means that calls will 139 -- actually be build-in-place in all cases. For other types, build-in-place 140 -- will be used when possible, but we need to make a copy in some 141 -- cases. For example, for "X := F(...);" if F can see X, or if F can 142 -- propagate exceptions, we need to store its result in a temp in general, 143 -- and copy the temp into X. Also, for "return Global_Var;" Global_Var 144 -- needs to be copied into the function result object. 145 146 function Is_Build_In_Place_Function (E : Entity_Id) return Boolean; 147 -- Ada 2005 (AI-318-02): Returns True if E denotes a function, generic 148 -- function, or access-to-function type for which 149 -- Is_Build_In_Place_Result_Type is True. However, we never use 150 -- build-in-place if the convention is other than Ada, because that would 151 -- disturb mixed-language programs. 152 153 function Is_Build_In_Place_Function_Call (N : Node_Id) return Boolean; 154 -- Ada 2005 (AI-318-02): Returns True if N denotes a call to a function 155 -- that requires handling as a build-in-place call (possibly qualified or 156 -- converted). 157 158 function Is_Null_Procedure (Subp : Entity_Id) return Boolean; 159 -- Predicate to recognize stubbed procedures and null procedures, which 160 -- can be inlined unconditionally in all cases. 161 162 procedure Make_Build_In_Place_Call_In_Allocator 163 (Allocator : Node_Id; 164 Function_Call : Node_Id); 165 -- Ada 2005 (AI-318-02): Handle a call to a build-in-place function that 166 -- occurs as the expression initializing an allocator, by passing access 167 -- to the allocated object as an additional parameter of the function call. 168 -- A new access object is declared that is initialized to the result of the 169 -- allocator, passed to the function, and the allocator is rewritten to 170 -- refer to that access object. Function_Call must denote either an 171 -- N_Function_Call node for which Is_Build_In_Place_Call is True, or else 172 -- an N_Qualified_Expression node applied to such a function call. 173 174 procedure Make_Build_In_Place_Call_In_Anonymous_Context 175 (Function_Call : Node_Id); 176 -- Ada 2005 (AI-318-02): Handle a call to a build-in-place function that 177 -- occurs in a context that does not provide a separate object. A temporary 178 -- object is created to act as the return object and an access to the 179 -- temporary is passed as an additional parameter of the call. This occurs 180 -- in contexts such as subprogram call actuals and object renamings. 181 -- Function_Call must denote either an N_Function_Call node for which 182 -- Is_Build_In_Place_Call is True, or else an N_Qualified_Expression node 183 -- applied to such a function call. 184 185 procedure Make_Build_In_Place_Call_In_Assignment 186 (Assign : Node_Id; 187 Function_Call : Node_Id); 188 -- Ada 2005 (AI-318-02): Handle a call to a build-in-place function that 189 -- occurs as the right-hand side of an assignment statement by passing 190 -- access to the left-hand side as an additional parameter of the function 191 -- call. Assign must denote a N_Assignment_Statement. Function_Call must 192 -- denote either an N_Function_Call node for which Is_Build_In_Place_Call 193 -- is True, or an N_Qualified_Expression node applied to such a function 194 -- call. 195 196 procedure Make_Build_In_Place_Call_In_Object_Declaration 197 (Obj_Decl : Node_Id; 198 Function_Call : Node_Id); 199 -- Ada 2005 (AI-318-02): Handle a call to a build-in-place function that 200 -- occurs as the expression initializing an object declaration by 201 -- passing access to the declared object as an additional parameter of the 202 -- function call. Function_Call must denote either an N_Function_Call node 203 -- for which Is_Build_In_Place_Call is True, or an N_Qualified_Expression 204 -- node applied to such a function call. 205 206 procedure Make_Build_In_Place_Iface_Call_In_Allocator 207 (Allocator : Node_Id; 208 Function_Call : Node_Id); 209 -- Ada 2005 (AI-318-02): Handle a call to a build-in-place function that 210 -- occurs as the expression initializing an allocator, by passing access 211 -- to the allocated object as an additional parameter of the function call. 212 -- Function_Call must denote an expression containing a BIP function call 213 -- and an enclosing call to Ada.Tags.Displace to displace the pointer to 214 -- the returned BIP object to reference the secondary dispatch table of 215 -- an interface. 216 217 procedure Make_Build_In_Place_Iface_Call_In_Anonymous_Context 218 (Function_Call : Node_Id); 219 -- Ada 2005 (AI-318-02): Handle a call to a build-in-place function that 220 -- occurs in a context that does not provide a separate object. A temporary 221 -- object is created to act as the return object and an access to the 222 -- temporary is passed as an additional parameter of the call. This occurs 223 -- in contexts such as subprogram call actuals and object renamings. 224 -- Function_Call must denote an expression containing a BIP function call 225 -- and an enclosing call to Ada.Tags.Displace to displace the pointer to 226 -- the returned BIP object to reference the secondary dispatch table of 227 -- an interface. 228 229 procedure Make_Build_In_Place_Iface_Call_In_Object_Declaration 230 (Obj_Decl : Node_Id; 231 Function_Call : Node_Id); 232 -- Ada 2005 (AI-318-02): Handle a call to a build-in-place function that 233 -- occurs as the expression initializing an object declaration by passing 234 -- access to the declared object as an additional parameter of the function 235 -- call. Function_Call must denote an expression containing a BIP function 236 -- call and an enclosing call to Ada.Tags.Displace to displace the pointer 237 -- to the returned BIP object to reference the secondary dispatch table of 238 -- an interface. 239 240 procedure Make_CPP_Constructor_Call_In_Allocator 241 (Allocator : Node_Id; 242 Function_Call : Node_Id); 243 -- Handle a call to a CPP constructor that occurs as the expression that 244 -- initializes an allocator, by passing access to the allocated object as 245 -- an additional parameter of the constructor call. A new access object is 246 -- declared that is initialized to the result of the allocator, passed to 247 -- the constructor, and the allocator is rewritten to refer to that access 248 -- object. Function_Call must denote a call to a CPP_Constructor function. 249 250 function Might_Have_Tasks (Typ : Entity_Id) return Boolean; 251 -- Return True when type Typ has tasks or when it is a limited class-wide 252 -- type (or subtype), since it might have task components. 253 254 function Needs_BIP_Alloc_Form (Func_Id : Entity_Id) return Boolean; 255 -- Ada 2005 (AI-318-02): Return True if the function needs an implicit 256 -- BIP_Alloc_Form parameter (see type BIP_Formal_Kind). 257 258 function Needs_BIP_Finalization_Master (Func_Id : Entity_Id) return Boolean; 259 -- Ada 2005 (AI-318-02): Return True if the result subtype of function 260 -- Func_Id might need finalization actions. This includes build-in-place 261 -- functions with tagged result types, since they can be invoked via 262 -- dispatching calls, and descendant types may require finalization. 263 264 function Needs_BIP_Task_Actuals (Func_Id : Entity_Id) return Boolean; 265 -- Return True if the function returns an object of a type that has tasks. 266 267 function Unqual_BIP_Iface_Function_Call (Expr : Node_Id) return Node_Id; 268 -- Return the inner BIP function call removing any qualification from Expr 269 -- including qualified expressions, type conversions, references, unchecked 270 -- conversions and calls to displace the pointer to the object, if Expr is 271 -- an expression containing a call displacing the pointer to the BIP object 272 -- to reference the secondary dispatch table of an interface; otherwise 273 -- return Empty. 274 275end Exp_Ch6; 276