1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2002, 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 2, 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 COPYING. If not, write --
19 -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
20 -- MA 02111-1307, USA. --
22 -- GNAT was originally developed by the GNAT team at New York University. --
23 -- Extensive contributions were provided by Ada Core Technologies Inc. --
25 ------------------------------------------------------------------------------
27 -- This package contains various utility procedures to assist in
28 -- building specific types of tree nodes.
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 function Make_Byte_Aligned_Attribute_Reference
52 Attribute_Name
: Name_Id
)
54 pragma Inline
(Make_Byte_Aligned_Attribute_Reference
);
55 -- Like the standard Make_Attribute_Reference but the special flag
56 -- Must_Be_Byte_Aligned is set in the attribute reference node. The
57 -- Attribute_Name must be Name_Address or Name_Unrestricted_Access.
59 function Make_DT_Component
64 -- Gives a reference to the Ith component of the Dispatch Table of
65 -- a given Tagged Type.
67 -- I = 1 --> Inheritance_Depth
68 -- I = 2 --> Tags (array of ancestors)
69 -- I = 3, 4 --> predefined primitive
70 -- function _Size (X : Typ) return Long_Long_Integer;
71 -- function _Equality (X : Typ; Y : Typ'Class) return Boolean;
72 -- I >= 5 --> User-Defined Primitive Operations
74 function Make_DT_Access
75 (Loc
: Source_Ptr
; Rec
: Node_Id
; Typ
: Entity_Id
) return Node_Id
;
76 -- Create an access to the Dispatch Table by using the Tag field
77 -- of a tagged record : Acc_Dt (Rec.tag).all
79 function Make_Implicit_If_Statement
82 Then_Statements
: List_Id
;
83 Elsif_Parts
: List_Id
:= No_List
;
84 Else_Statements
: List_Id
:= No_List
)
86 pragma Inline
(Make_Implicit_If_Statement
);
87 -- This function makes an N_If_Statement node whose fields are filled
88 -- in with the indicated values (see Sinfo), and whose Sloc field is
89 -- is set to Sloc (Node). The effect is identical to calling function
90 -- Nmake.Make_If_Statement except that there is a check for restriction
91 -- No_Implicit_Conditionals, and if this restriction is being violated,
92 -- an error message is posted on Node.
94 function Make_Implicit_Label_Declaration
96 Defining_Identifier
: Node_Id
;
97 Label_Construct
: Node_Id
)
99 -- Used to construct an implicit label declaration node, including setting
100 -- the proper Label_Construct field (since Label_Construct is a semantic
101 -- field, the normal call to Make_Implicit_Label_Declaration does not
104 function Make_Implicit_Loop_Statement
106 Statements
: List_Id
;
107 Identifier
: Node_Id
:= Empty
;
108 Iteration_Scheme
: Node_Id
:= Empty
;
109 Has_Created_Identifier
: Boolean := False;
110 End_Label
: Node_Id
:= Empty
)
112 -- This function makes an N_Loop_Statement node whose fields are filled
113 -- in with the indicated values (see Sinfo), and whose Sloc field is
114 -- is set to Sloc (Node). The effect is identical to calling function
115 -- Nmake.Make_Loop_Statement except that there is a check for restrictions
116 -- No_Implicit_Loops and No_Implicit_Conditionals (the first applying in
117 -- all cases, and the second only for while loops), and if one of these
118 -- restrictions is being violated, an error message is posted on Node.
120 function Make_Integer_Literal
124 pragma Inline
(Make_Integer_Literal
);
125 -- A convenient form of Make_Integer_Literal taking Int instead of Uint
127 function Make_Raise_Constraint_Error
129 Condition
: Node_Id
:= Empty
;
130 Reason
: RT_Exception_Code
)
132 pragma Inline
(Make_Raise_Constraint_Error
);
133 -- A convenient form of Make_Raise_Constraint_Error where the Reason
134 -- is given simply as an enumeration value, rather than a Uint code.
136 function Make_Raise_Program_Error
138 Condition
: Node_Id
:= Empty
;
139 Reason
: RT_Exception_Code
)
141 pragma Inline
(Make_Raise_Program_Error
);
142 -- A convenient form of Make_Raise_Program_Error where the Reason
143 -- is given simply as an enumeration value, rather than a Uint code.
145 function Make_Raise_Storage_Error
147 Condition
: Node_Id
:= Empty
;
148 Reason
: RT_Exception_Code
)
150 pragma Inline
(Make_Raise_Storage_Error
);
151 -- A convenient form of Make_Raise_Storage_Error where the Reason
152 -- is given simply as an enumeration value, rather than a Uint code.
154 function Make_Unsuppress_Block
159 -- Build a block with a pragma Suppress on 'Check'. Stmts is the
160 -- statements list that needs protection against the check
162 function New_Constraint_Error
(Loc
: Source_Ptr
) return Node_Id
;
163 -- This function builds a tree corresponding to the Ada statement
164 -- "raise Constraint_Error" and returns the root of this tree,
165 -- the N_Raise_Statement node.
167 function New_External_Name
168 (Related_Id
: Name_Id
;
169 Suffix
: Character := ' ';
170 Suffix_Index
: Int
:= 0;
171 Prefix
: Character := ' ')
173 function New_External_Name
174 (Related_Id
: Name_Id
;
176 Suffix_Index
: Int
:= 0;
177 Prefix
: Character := ' ')
179 -- Builds a new entry in the names table of the form:
181 -- [Prefix &] Related_Id [& Suffix] [& Suffix_Index]
183 -- Prefix is prepended only if Prefix is non-blank (in which case it
184 -- must be an upper case letter other than O,Q,U,W (which are used for
185 -- identifier encoding, see Namet), and T is reserved for use by implicit
186 -- types. and X is reserved for use by debug type encoding (see package
187 -- Exp_Dbug). Note: the reason that Prefix is last is that it is almost
188 -- always omitted. The notable case of Prefix being non-null is when
189 -- it is 'T' for an implicit type.
191 -- Suffix_Index'Image is appended only if the value of Suffix_Index is
192 -- positive, or if Suffix_Index is negative 1, then a unique serialized
193 -- suffix is added. If Suffix_Index is zero, then no index is appended.
195 -- Suffix is also a single upper case letter other than O,Q,U,W,X and is a
196 -- required parameter (T is permitted). The constructed name is stored
197 -- using Find_Name so that it can be located using a subsequent Find_Name
198 -- operation (i.e. it is properly hashed into the names table). The upper
199 -- case letter given as the Suffix argument ensures that the name does
200 -- not clash with any Ada identifier name. These generated names are
201 -- permitted, but not required, to be made public by setting the flag
202 -- Is_Public in the associated entity.
204 function New_External_Name
208 -- Builds a new entry in the names table of the form
209 -- Suffix & Suffix_Index'Image
210 -- where Suffix is a single upper case letter other than O,Q,U,W,X and is
211 -- a required parameter (T is permitted). The constructed name is stored
212 -- using Find_Name so that it can be located using a subsequent Find_Name
213 -- operation (i.e. it is properly hashed into the names table). The upper
214 -- case letter given as the Suffix argument ensures that the name does
215 -- not clash with any Ada identifier name. These generated names are
216 -- permitted, but not required, to be made public by setting the flag
217 -- Is_Public in the associated entity.
219 function New_Internal_Name
(Id_Char
: Character) return Name_Id
;
220 -- Id_Char is an upper case letter other than O,Q,U,W (which are reserved
221 -- for identifier encoding (see Namet package for details) and X which is
222 -- used for debug encoding (see Exp_Dbug). The letter T is permitted, but
223 -- is reserved by convention for the case of internally generated types.
224 -- The result of the call is a new generated unique name of the form XyyyU
225 -- where X is Id_Char, yyy is a unique serial number, and U is either a
226 -- lower case s or b indicating if the current unit is a spec or a body.
228 -- The name is entered into the names table using Name_Enter rather than
229 -- Name_Find, because there can never be a need to locate the entry using
230 -- the Name_Find procedure later on. Names created by New_Internal_Name
231 -- are guaranteed to be consistent from one compilation to another (i.e.
232 -- if the identical unit is compiled with a semantically consistent set
233 -- of sources, the numbers will be consistent. This means that it is fine
234 -- to use these as public symbols.
236 function New_Occurrence_Of
240 -- New_Occurrence_Of creates an N_Identifier node which is an
241 -- occurrence of the defining identifier which is passed as its
242 -- argument. The Entity and Etype of the result are set from
243 -- the given defining identifier as follows: Entity is simply
244 -- a copy of Def_Id. Etype is a copy of Def_Id for types, and
245 -- a copy of the Etype of Def_Id for other entities.
247 function New_Reference_To
251 -- This is like New_Occurrence_Of, but it does not set the Etype field.
252 -- It is used from the expander, where Etype fields are generally not set,
253 -- since they are set when the expanded tree is reanalyzed.
255 function New_Suffixed_Name
256 (Related_Id
: Name_Id
;
259 -- This function is used to create special suffixed names used by the
260 -- debugger. Suffix is a string of upper case letters, used to construct
261 -- the required name. For instance, the special type used to record the
262 -- fixed-point small is called typ_SMALL where typ is the name of the
263 -- fixed-point type (as passed in Related_Id), and Suffix is "SMALL".
265 function OK_Convert_To
(Typ
: Entity_Id
; Expr
: Node_Id
) return Node_Id
;
266 -- Like Convert_To, except that a conversion node is always generated,
267 -- and the Conversion_OK flag is set on this conversion node.
269 function Unchecked_Convert_To
273 -- Like Convert_To, but if a conversion is actually needed, constructs
274 -- an N_Unchecked_Type_Conversion node to do the required conversion.