1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2008, 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 -- This package contains various utility procedures to assist in
27 -- building specific types of tree nodes.
29 with Namet; use Namet;
30 with Types; use Types;
34 function Checks_Off (N : Node_Id) return Node_Id;
35 pragma Inline (Checks_Off);
36 -- Returns an N_Unchecked_Expression node whose expression is the given
37 -- argument. The results is a subexpression identical to the argument,
38 -- except that it will be analyzed and resolved with checks off.
40 function Convert_To (Typ : Entity_Id; Expr : Node_Id) return Node_Id;
41 -- Returns an expression that represents the result of a checked convert
42 -- of expression Exp to type T. If the base type of Exp is T, then no
43 -- conversion is required, and Exp is returned unchanged. Otherwise an
44 -- N_Type_Conversion node is constructed to convert the expression.
45 -- If an N_Type_Conversion node is required, Relocate_Node is used on
46 -- Exp. This means that it is safe to replace a node by a Convert_To
47 -- of itself to some other type.
49 procedure Discard_Node (N : Node_Or_Entity_Id);
50 pragma Inline (Discard_Node);
51 -- This is a dummy procedure that simply returns and does nothing. It is
52 -- used when a function returning a Node_Id value is called for its side
53 -- effect (e.g. a call to Make to construct a node) but the Node_Id value
56 procedure Discard_List (L : List_Id);
57 pragma Inline (Discard_List);
58 -- This is a dummy procedure that simply returns and does nothing. It is
59 -- used when a function returning a Node_Id value is called for its side
60 -- effect (e.g. a call to the parser to parse a list of compilation
61 -- units), but the List_Id value is not required.
63 function Make_Byte_Aligned_Attribute_Reference
66 Attribute_Name : Name_Id) return Node_Id;
67 pragma Inline (Make_Byte_Aligned_Attribute_Reference);
68 -- Like the standard Make_Attribute_Reference but the special flag
69 -- Must_Be_Byte_Aligned is set in the attribute reference node. The
70 -- Attribute_Name must be Name_Address or Name_Unrestricted_Access.
72 function Make_DT_Access
73 (Loc : Source_Ptr; Rec : Node_Id; Typ : Entity_Id) return Node_Id;
74 -- Create an access to the Dispatch Table by using the Tag field of a
75 -- tagged record : Acc_Dt (Rec.tag).all
77 function Make_Implicit_Exception_Handler
79 Choice_Parameter : Node_Id := Empty;
80 Exception_Choices : List_Id;
81 Statements : List_Id) return Node_Id;
82 pragma Inline (Make_Implicit_Exception_Handler);
83 -- This is just like Make_Exception_Handler, except that it also sets the
84 -- Local_Raise_Statements field to No_Elist, ensuring that it is properly
85 -- initialized. This should always be used when creating implicit exception
86 -- handlers during expansion (i.e. handlers that do not correspond to user
87 -- source program exception handlers).
89 function Make_Implicit_If_Statement
92 Then_Statements : List_Id;
93 Elsif_Parts : List_Id := No_List;
94 Else_Statements : List_Id := No_List) return Node_Id;
95 pragma Inline (Make_Implicit_If_Statement);
96 -- This function makes an N_If_Statement node whose fields are filled
97 -- in with the indicated values (see Sinfo), and whose Sloc field is
98 -- is set to Sloc (Node). The effect is identical to calling function
99 -- Nmake.Make_If_Statement except that there is a check for restriction
100 -- No_Implicit_Conditionals, and if this restriction is being violated,
101 -- an error message is posted on Node.
103 function Make_Implicit_Label_Declaration
105 Defining_Identifier : Node_Id;
106 Label_Construct : Node_Id) return Node_Id;
107 -- Used to construct an implicit label declaration node, including setting
108 -- the proper Label_Construct field (since Label_Construct is a semantic
109 -- field, the normal call to Make_Implicit_Label_Declaration does not
112 function Make_Implicit_Loop_Statement
114 Statements : List_Id;
115 Identifier : Node_Id := Empty;
116 Iteration_Scheme : Node_Id := Empty;
117 Has_Created_Identifier : Boolean := False;
118 End_Label : Node_Id := Empty) return Node_Id;
119 -- This function makes an N_Loop_Statement node whose fields are filled
120 -- in with the indicated values (see Sinfo), and whose Sloc field is
121 -- is set to Sloc (Node). The effect is identical to calling function
122 -- Nmake.Make_Loop_Statement except that there is a check for restrictions
123 -- No_Implicit_Loops and No_Implicit_Conditionals (the first applying in
124 -- all cases, and the second only for while loops), and if one of these
125 -- restrictions is being violated, an error message is posted on Node.
127 function Make_Integer_Literal
129 Intval : Int) return Node_Id;
130 pragma Inline (Make_Integer_Literal);
131 -- A convenient form of Make_Integer_Literal taking Int instead of Uint
133 function Make_Linker_Section_Pragma
136 Sec : String) return Node_Id;
137 -- Construct a Linker_Section pragma for entity Ent, using string Sec as
138 -- the section name. Loc is the Sloc value to use in building the pragma.
143 Pragma_Argument_Associations : List_Id := No_List;
144 Debug_Statement : Node_Id := Empty) return Node_Id;
145 -- A convenient form of Make_Pragma not requiring a Pragma_Identifier
146 -- argument (this argument is built from the value given for Chars).
148 function Make_Raise_Constraint_Error
150 Condition : Node_Id := Empty;
151 Reason : RT_Exception_Code) return Node_Id;
152 pragma Inline (Make_Raise_Constraint_Error);
153 -- A convenient form of Make_Raise_Constraint_Error where the Reason
154 -- is given simply as an enumeration value, rather than a Uint code.
156 function Make_Raise_Program_Error
158 Condition : Node_Id := Empty;
159 Reason : RT_Exception_Code) return Node_Id;
160 pragma Inline (Make_Raise_Program_Error);
161 -- A convenient form of Make_Raise_Program_Error where the Reason
162 -- is given simply as an enumeration value, rather than a Uint code.
164 function Make_Raise_Storage_Error
166 Condition : Node_Id := Empty;
167 Reason : RT_Exception_Code) return Node_Id;
168 pragma Inline (Make_Raise_Storage_Error);
169 -- A convenient form of Make_Raise_Storage_Error where the Reason
170 -- is given simply as an enumeration value, rather than a Uint code.
172 function Make_String_Literal
174 Strval : String) return Node_Id;
175 -- A convenient form of Make_String_Literal, where the string value
176 -- is given as a normal string instead of a String_Id value.
178 function Make_Unsuppress_Block
181 Stmts : List_Id) return Node_Id;
182 -- Build a block with a pragma Suppress on 'Check'. Stmts is the
183 -- statements list that needs protection against the check
185 function New_Constraint_Error (Loc : Source_Ptr) return Node_Id;
186 -- This function builds a tree corresponding to the Ada statement
187 -- "raise Constraint_Error" and returns the root of this tree,
188 -- the N_Raise_Statement node.
190 function New_External_Name
191 (Related_Id : Name_Id;
192 Suffix : Character := ' ';
193 Suffix_Index : Int := 0;
194 Prefix : Character := ' ') return Name_Id;
195 function New_External_Name
196 (Related_Id : Name_Id;
198 Suffix_Index : Int := 0;
199 Prefix : Character := ' ') return Name_Id;
200 -- Builds a new entry in the names table of the form:
202 -- [Prefix &] Related_Id [& Suffix] [& Suffix_Index]
204 -- Prefix is prepended only if Prefix is non-blank (in which case it
205 -- must be an upper case letter other than O,Q,U,W (which are used for
206 -- identifier encoding, see Namet), or an underscore, and T is reserved for
207 -- use by implicit types, and X is reserved for use by debug type encoding
208 -- (see package Exp_Dbug). Note: the reason that Prefix is last is that it
209 -- is almost always omitted. The notable case of Prefix being non-null is
210 -- when it is 'T' for an implicit type.
212 -- Suffix_Index'Image is appended only if the value of Suffix_Index is
213 -- positive, or if Suffix_Index is negative 1, then a unique serialized
214 -- suffix is added. If Suffix_Index is zero, then no index is appended.
216 -- Suffix is also a single upper case letter other than O,Q,U,W,X and is a
217 -- required parameter (T is permitted). The constructed name is stored
218 -- using Name_Find so that it can be located using a subsequent Name_Find
219 -- operation (i.e. it is properly hashed into the names table). The upper
220 -- case letter given as the Suffix argument ensures that the name does
221 -- not clash with any Ada identifier name. These generated names are
222 -- permitted, but not required, to be made public by setting the flag
223 -- Is_Public in the associated entity.
225 function New_External_Name
227 Suffix_Index : Nat) return Name_Id;
228 -- Builds a new entry in the names table of the form
229 -- Suffix & Suffix_Index'Image
230 -- where Suffix is a single upper case letter other than O,Q,U,W,X and is
231 -- a required parameter (T is permitted). The constructed name is stored
232 -- using Name_Find so that it can be located using a subsequent Name_Find
233 -- operation (i.e. it is properly hashed into the names table). The upper
234 -- case letter given as the Suffix argument ensures that the name does
235 -- not clash with any Ada identifier name. These generated names are
236 -- permitted, but not required, to be made public by setting the flag
237 -- Is_Public in the associated entity.
239 function New_Internal_Name (Id_Char : Character) return Name_Id;
240 -- Id_Char is an upper case letter other than O,Q,U,W (which are reserved
241 -- for identifier encoding (see Namet package for details) and X which is
242 -- used for debug encoding (see Exp_Dbug). The letter T is permitted, but
243 -- is reserved by convention for the case of internally generated types.
244 -- The result of the call is a new generated unique name of the form XyyyU
245 -- where X is Id_Char, yyy is a unique serial number, and U is either a
246 -- lower case s or b indicating if the current unit is a spec or a body.
248 -- The name is entered into the names table using Name_Enter rather than
249 -- Name_Find, because there can never be a need to locate the entry using
250 -- the Name_Find procedure later on. Names created by New_Internal_Name
251 -- are guaranteed to be consistent from one compilation to another (i.e.
252 -- if the identical unit is compiled with a semantically consistent set
253 -- of sources, the numbers will be consistent. This means that it is fine
254 -- to use these as public symbols.
256 function New_Occurrence_Of
258 Loc : Source_Ptr) return Node_Id;
259 -- New_Occurrence_Of creates an N_Identifier node which is an
260 -- occurrence of the defining identifier which is passed as its
261 -- argument. The Entity and Etype of the result are set from
262 -- the given defining identifier as follows: Entity is simply
263 -- a copy of Def_Id. Etype is a copy of Def_Id for types, and
264 -- a copy of the Etype of Def_Id for other entities.
266 function New_Reference_To
268 Loc : Source_Ptr) return Node_Id;
269 -- This is like New_Occurrence_Of, but it does not set the Etype field.
270 -- It is used from the expander, where Etype fields are generally not set,
271 -- since they are set when the expanded tree is reanalyzed.
273 function New_Suffixed_Name
274 (Related_Id : Name_Id;
275 Suffix : String) return Name_Id;
276 -- This function is used to create special suffixed names used by the
277 -- debugger. Suffix is a string of upper case letters, used to construct
278 -- the required name. For instance, the special type used to record the
279 -- fixed-point small is called typ_SMALL where typ is the name of the
280 -- fixed-point type (as passed in Related_Id), and Suffix is "SMALL".
282 function OK_Convert_To (Typ : Entity_Id; Expr : Node_Id) return Node_Id;
283 -- Like Convert_To, except that a conversion node is always generated,
284 -- and the Conversion_OK flag is set on this conversion node.
286 function Unchecked_Convert_To
288 Expr : Node_Id) return Node_Id;
289 -- Like Convert_To, but if a conversion is actually needed, constructs
290 -- an N_Unchecked_Type_Conversion node to do the required conversion.