1------------------------------------------------------------------------------
2--                                                                          --
3--                         GNAT COMPILER COMPONENTS                         --
4--                                                                          --
5--                                N A M E T                                 --
6--                                                                          --
7--                                 S p e c                                  --
8--                                                                          --
9--          Copyright (C) 1992-2013, 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.                                     --
17--                                                                          --
18-- As a special exception under Section 7 of GPL version 3, you are granted --
19-- additional permissions described in the GCC Runtime Library Exception,   --
20-- version 3.1, as published by the Free Software Foundation.               --
21--                                                                          --
22-- You should have received a copy of the GNU General Public License and    --
23-- a copy of the GCC Runtime Library Exception along with this program;     --
24-- see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see    --
25-- <http://www.gnu.org/licenses/>.                                          --
26--                                                                          --
27-- GNAT was originally developed  by the GNAT team at  New York University. --
28-- Extensive contributions were provided by Ada Core Technologies Inc.      --
29--                                                                          --
30------------------------------------------------------------------------------
31
32with Alloc;
33with Table;
34with Hostparm; use Hostparm;
35with System;   use System;
36with Types;    use Types;
37
38package Namet is
39
40--  WARNING: There is a C version of this package. Any changes to this
41--  source file must be properly reflected in the C header file namet.h
42--  which is created manually from namet.ads and namet.adb.
43
44--  This package contains routines for handling the names table. The table
45--  is used to store character strings for identifiers and operator symbols,
46--  as well as other string values such as unit names and file names.
47
48--  The forms of the entries are as follows:
49
50--    Identifiers        Stored with upper case letters folded to lower case.
51--                       Upper half (16#80# bit set) and wide characters are
52--                       stored in an encoded form (Uhh for upper half char,
53--                       Whhhh for wide characters, WWhhhhhhhh as provided by
54--                       the routine Store_Encoded_Character, where hh are hex
55--                       digits for the character code using lower case a-f).
56--                       Normally the use of U or W in other internal names is
57--                       avoided, but these letters may be used in internal
58--                       names (without this special meaning), if they appear
59--                       as the last character of the name, or they are
60--                       followed by an upper case letter (other than the WW
61--                       sequence), or an underscore.
62
63--    Operator symbols   Stored with an initial letter O, and the remainder
64--                       of the name is the lower case characters XXX where
65--                       the name is Name_Op_XXX, see Snames spec for a full
66--                       list of the operator names. Normally the use of O
67--                       in other internal names is avoided, but it may be
68--                       used in internal names (without this special meaning)
69--                       if it is the last character of the name, or if it is
70--                       followed by an upper case letter or an underscore.
71
72--    Character literals Character literals have names that are used only for
73--                       debugging and error message purposes. The form is an
74--                       upper case Q followed by a single lower case letter,
75--                       or by a Uxx/Wxxxx/WWxxxxxxx encoding as described for
76--                       identifiers. The Set_Character_Literal_Name procedure
77--                       should be used to construct these encodings. Normally
78--                       the use of O in other internal names is avoided, but
79--                       it may be used in internal names (without this special
80--                       meaning) if it is the last character of the name, or
81--                       if it is followed by an upper case letter or an
82--                       underscore.
83
84--    Unit names         Stored with upper case letters folded to lower case,
85--                       using Uhh/Whhhh/WWhhhhhhhh encoding as described for
86--                       identifiers, and a %s or %b suffix for specs/bodies.
87--                       See package Uname for further details.
88
89--    File names         Are stored in the form provided by Osint. Typically
90--                       they may include wide character escape sequences and
91--                       upper case characters (in non-encoded form). Casing
92--                       is also derived from the external environment. Note
93--                       that file names provided by Osint must generally be
94--                       consistent with the names from Fname.Get_File_Name.
95
96--    Other strings      The names table is also used as a convenient storage
97--                       location for other variable length strings such as
98--                       error messages etc. There are no restrictions on what
99--                       characters may appear for such entries.
100
101--  Note: the encodings Uhh (upper half characters), Whhhh (wide characters),
102--  WWhhhhhhhh (wide wide characters) and Qx (character literal names) are
103--  described in the spec, since they are visible throughout the system (e.g.
104--  in debugging output). However, no code should depend on these particular
105--  encodings, so it should be possible to change the encodings by making
106--  changes only to the Namet specification (to change these comments) and the
107--  body (which actually implements the encodings).
108
109--  The names are hashed so that a given name appears only once in the table,
110--  except that names entered with Name_Enter as opposed to Name_Find are
111--  omitted from the hash table.
112
113--  The first 26 entries in the names table (with Name_Id values in the range
114--  First_Name_Id .. First_Name_Id + 25) represent names which are the one
115--  character lower case letters in the range a-z, and these names are created
116--  and initialized by the Initialize procedure.
117
118--  Two values, one of type Int and one of type Byte, are stored with each
119--  names table entry and subprograms are provided for setting and retrieving
120--  these associated values. The usage of these values is up to the client. In
121--  the compiler, the Int field is used to point to a chain of potentially
122--  visible entities (see Sem.Ch8 for details), and the Byte field is used to
123--  hold the Token_Type value for reserved words (see Sem for details). In the
124--  binder, the Byte field is unused, and the Int field is used in various
125--  ways depending on the name involved (see binder documentation).
126
127   Name_Buffer : String (1 .. 4 * Max_Line_Length);
128   --  This buffer is used to set the name to be stored in the table for the
129   --  Name_Find call, and to retrieve the name for the Get_Name_String call.
130   --  The limit here is intended to be an infinite value that ensures that we
131   --  never overflow the buffer (names this long are too absurd to worry).
132
133   Name_Len : Natural := 0;
134   --  Length of name stored in Name_Buffer. Used as an input parameter for
135   --  Name_Find, and as an output value by Get_Name_String, or Write_Name.
136   --  Note: in normal usage, all users of Name_Buffer/Name_Len are expected
137   --  to initialize Name_Len appropriately. The reason we preinitialize to
138   --  zero here is that some circuitry (e.g. Osint.Write_Program_Name) does
139   --  a save/restore on Name_Len and Name_Buffer (1 .. Name_Len), and we do
140   --  not want some arbitrary junk value to result in saving an arbitrarily
141   --  long slice which would waste time and blow the stack.
142
143   -----------------------------
144   -- Types for Namet Package --
145   -----------------------------
146
147   --  Name_Id values are used to identify entries in the names table. Except
148   --  for the special values No_Name and Error_Name, they are subscript values
149   --  for the Names table defined in this package.
150
151   --  Note that with only a few exceptions, which are clearly documented, the
152   --  type Name_Id should be regarded as a private type. In particular it is
153   --  never appropriate to perform arithmetic operations using this type.
154
155   type Name_Id is range Names_Low_Bound .. Names_High_Bound;
156   for Name_Id'Size use 32;
157   --  Type used to identify entries in the names table
158
159   No_Name : constant Name_Id := Names_Low_Bound;
160   --  The special Name_Id value No_Name is used in the parser to indicate
161   --  a situation where no name is present (e.g. on a loop or block).
162
163   Error_Name : constant Name_Id := Names_Low_Bound +  1;
164   --  The special Name_Id value Error_Name is used in the parser to
165   --  indicate that some kind of error was encountered in scanning out
166   --  the relevant name, so it does not have a representable label.
167
168   subtype Error_Name_Or_No_Name is Name_Id range No_Name .. Error_Name;
169   --  Used to test for either error name or no name
170
171   First_Name_Id : constant Name_Id := Names_Low_Bound + 2;
172   --  Subscript of first entry in names table
173
174   ------------------------------
175   -- Name_Id Membership Tests --
176   ------------------------------
177
178   --  The following functions allow a convenient notation for testing whether
179   --  a Name_Id value matches any one of a list of possible values. In each
180   --  case True is returned if the given T argument is equal to any of the V
181   --  arguments. These essentially duplicate the Ada 2012 membership tests,
182   --  but we cannot use the latter (yet) in the compiler front end, because
183   --  of bootstrap considerations
184
185   function Nam_In
186     (T  : Name_Id;
187      V1 : Name_Id;
188      V2 : Name_Id) return Boolean;
189
190   function Nam_In
191     (T  : Name_Id;
192      V1 : Name_Id;
193      V2 : Name_Id;
194      V3 : Name_Id) return Boolean;
195
196   function Nam_In
197     (T  : Name_Id;
198      V1 : Name_Id;
199      V2 : Name_Id;
200      V3 : Name_Id;
201      V4 : Name_Id) return Boolean;
202
203   function Nam_In
204     (T  : Name_Id;
205      V1 : Name_Id;
206      V2 : Name_Id;
207      V3 : Name_Id;
208      V4 : Name_Id;
209      V5 : Name_Id) return Boolean;
210
211   function Nam_In
212     (T  : Name_Id;
213      V1 : Name_Id;
214      V2 : Name_Id;
215      V3 : Name_Id;
216      V4 : Name_Id;
217      V5 : Name_Id;
218      V6 : Name_Id) return Boolean;
219
220   function Nam_In
221     (T  : Name_Id;
222      V1 : Name_Id;
223      V2 : Name_Id;
224      V3 : Name_Id;
225      V4 : Name_Id;
226      V5 : Name_Id;
227      V6 : Name_Id;
228      V7 : Name_Id) return Boolean;
229
230   pragma Inline (Nam_In);
231   --  Inline all above functions
232
233   -----------------
234   -- Subprograms --
235   -----------------
236
237   procedure Finalize;
238   --  Called at the end of a use of the Namet package (before a subsequent
239   --  call to Initialize). Currently this routine is only used to generate
240   --  debugging output.
241
242   procedure Get_Name_String (Id : Name_Id);
243   --  Get_Name_String is used to retrieve the string associated with an entry
244   --  in the names table. The resulting string is stored in Name_Buffer and
245   --  Name_Len is set. It is an error to call Get_Name_String with one of the
246   --  special name Id values (No_Name or Error_Name).
247
248   function Get_Name_String (Id : Name_Id) return String;
249   --  This functional form returns the result as a string without affecting
250   --  the contents of either Name_Buffer or Name_Len. The lower bound is 1.
251
252   procedure Get_Unqualified_Name_String (Id : Name_Id);
253   --  Similar to the above except that qualification (as defined in unit
254   --  Exp_Dbug) is removed (including both preceding __ delimited names, and
255   --  also the suffixes used to indicate package body entities and to
256   --  distinguish between overloaded entities). Note that names are not
257   --  qualified until just before the call to gigi, so this routine is only
258   --  needed by processing that occurs after gigi has been called. This
259   --  includes all ASIS processing, since ASIS works on the tree written
260   --  after gigi has been called.
261
262   procedure Get_Name_String_And_Append (Id : Name_Id);
263   --  Like Get_Name_String but the resulting characters are appended to the
264   --  current contents of the entry stored in Name_Buffer, and Name_Len is
265   --  incremented to include the added characters.
266
267   procedure Get_Decoded_Name_String (Id : Name_Id);
268   --  Same calling sequence an interface as Get_Name_String, except that the
269   --  result is decoded, so that upper half characters and wide characters
270   --  appear as originally found in the source program text, operators have
271   --  their source forms (special characters and enclosed in quotes), and
272   --  character literals appear surrounded by apostrophes.
273
274   procedure Get_Unqualified_Decoded_Name_String (Id : Name_Id);
275   --  Similar to the above except that qualification (as defined in unit
276   --  Exp_Dbug) is removed (including both preceding __ delimited names, and
277   --  also the suffix used to indicate package body entities). Note that
278   --  names are not qualified until just before the call to gigi, so this
279   --  routine is only needed by processing that occurs after gigi has been
280   --  called. This includes all ASIS processing, since ASIS works on the tree
281   --  written after gigi has been called.
282
283   procedure Get_Decoded_Name_String_With_Brackets (Id : Name_Id);
284   --  This routine is similar to Decoded_Name, except that the brackets
285   --  notation (Uhh replaced by ["hh"], Whhhh replaced by ["hhhh"],
286   --  WWhhhhhhhh replaced by ["hhhhhhhh"]) is used for all non-lower half
287   --  characters, regardless of how Opt.Wide_Character_Encoding_Method is
288   --  set, and also in that characters in the range 16#80# .. 16#FF# are
289   --  converted to brackets notation in all cases. This routine can be used
290   --  when there is a requirement for a canonical representation not affected
291   --  by the character set options (e.g. in the binder generation of
292   --  symbols).
293
294   function Get_Name_Table_Byte (Id : Name_Id) return Byte;
295   pragma Inline (Get_Name_Table_Byte);
296   --  Fetches the Byte value associated with the given name
297
298   function Get_Name_Table_Info (Id : Name_Id) return Int;
299   pragma Inline (Get_Name_Table_Info);
300   --  Fetches the Int value associated with the given name
301
302   function Is_Operator_Name (Id : Name_Id) return Boolean;
303   --  Returns True if name given is of the form of an operator (that
304   --  is, it starts with an upper case O).
305
306   procedure Initialize;
307   --  This is a dummy procedure. It is retained for easy compatibility with
308   --  clients who used to call Initialize when this call was required. Now
309   --  initialization is performed automatically during package elaboration.
310   --  Note that this change fixes problems which existed prior to the change
311   --  of Initialize being called more than once. See also Reinitialize which
312   --  allows reinitialization of the tables.
313
314   procedure Lock;
315   --  Lock name tables before calling back end. We reserve some extra space
316   --  before locking to avoid unnecessary inefficiencies when we unlock.
317
318   procedure Reinitialize;
319   --  Clears the name tables and removes all existing entries from the table.
320
321   procedure Unlock;
322   --  Unlocks the name table to allow use of the extra space reserved by the
323   --  call to Lock. See gnat1drv for details of the need for this.
324
325   function Length_Of_Name (Id : Name_Id) return Nat;
326   pragma Inline (Length_Of_Name);
327   --  Returns length of given name in characters. This is the length of the
328   --  encoded name, as stored in the names table, the result is equivalent to
329   --  calling Get_Name_String and reading Name_Len, except that a call to
330   --  Length_Of_Name does not affect the contents of Name_Len and Name_Buffer.
331
332   function Name_Chars_Address return System.Address;
333   --  Return starting address of name characters table (used in Back_End call
334   --  to Gigi).
335
336   function Name_Find return Name_Id;
337   --  Name_Find is called with a string stored in Name_Buffer whose length is
338   --  in Name_Len (i.e. the characters of the name are in subscript positions
339   --  1 to Name_Len in Name_Buffer). It searches the names table to see if
340   --  the string has already been stored. If so the Id of the existing entry
341   --  is returned. Otherwise a new entry is created with its Name_Table_Info
342   --  field set to zero. The contents of Name_Buffer and Name_Len are not
343   --  modified by this call. Note that it is permissible for Name_Len to be
344   --  set to zero to lookup the null name string.
345
346   function Name_Enter return Name_Id;
347   --  Name_Enter has the same calling interface as Name_Find. The difference
348   --  is that it does not search the table for an existing match, and also
349   --  subsequent Name_Find calls using the same name will not locate the
350   --  entry created by this call. Thus multiple calls to Name_Enter with the
351   --  same name will create multiple entries in the name table with different
352   --  Name_Id values. This is useful in the case of created names, which are
353   --  never expected to be looked up. Note: Name_Enter should never be used
354   --  for one character names, since these are efficiently located without
355   --  hashing by Name_Find in any case.
356
357   function Name_Entries_Address return System.Address;
358   --  Return starting address of Names table (used in Back_End call to Gigi)
359
360   function Name_Entries_Count return Nat;
361   --  Return current number of entries in the names table
362
363   function Is_OK_Internal_Letter (C : Character) return Boolean;
364   pragma Inline (Is_OK_Internal_Letter);
365   --  Returns true if C is a suitable character for using as a prefix or a
366   --  suffix of an internally generated name, i.e. it is an upper case letter
367   --  other than one of the ones used for encoding source names (currently
368   --  the set of reserved letters is O, Q, U, W) and also returns False for
369   --  the letter X, which is reserved for debug output (see Exp_Dbug).
370
371   function Is_Internal_Name (Id : Name_Id) return Boolean;
372   --  Returns True if the name is an internal name (i.e. contains a character
373   --  for which Is_OK_Internal_Letter is true, or if the name starts or ends
374   --  with an underscore. This call destroys the value of Name_Len and
375   --  Name_Buffer (it loads these as for Get_Name_String).
376   --
377   --  Note: if the name is qualified (has a double underscore), then only the
378   --  final entity name is considered, not the qualifying names. Consider for
379   --  example that the name:
380   --
381   --    pkg__B_1__xyz
382   --
383   --  is not an internal name, because the B comes from the internal name of
384   --  a qualifying block, but the xyz means that this was indeed a declared
385   --  identifier called "xyz" within this block and there is nothing internal
386   --  about that name.
387
388   function Is_Internal_Name return Boolean;
389   --  Like the form with an Id argument, except that the name to be tested is
390   --  passed in Name_Buffer and Name_Len (which are not affected by the call).
391   --  Name_Buffer (it loads these as for Get_Name_String).
392
393   function Is_Valid_Name (Id : Name_Id) return Boolean;
394   --  True if Id is a valid name -- points to a valid entry in the
395   --  Name_Entries table.
396
397   procedure Reset_Name_Table;
398   --  This procedure is used when there are multiple source files to reset
399   --  the name table info entries associated with current entries in the
400   --  names table. There is no harm in keeping the names entries themselves
401   --  from one compilation to another, but we can't keep the entity info,
402   --  since this refers to tree nodes, which are destroyed between each main
403   --  source file.
404
405   procedure Add_Char_To_Name_Buffer (C : Character);
406   pragma Inline (Add_Char_To_Name_Buffer);
407   --  Add given character to the end of the string currently stored in the
408   --  Name_Buffer, incrementing Name_Len.
409
410   procedure Add_Nat_To_Name_Buffer (V : Nat);
411   --  Add decimal representation of given value to the end of the string
412   --  currently stored in Name_Buffer, incrementing Name_Len as required.
413
414   procedure Add_Str_To_Name_Buffer (S : String);
415   --  Add characters of string S to the end of the string currently stored
416   --  in the Name_Buffer, incrementing Name_Len by the length of the string.
417
418   procedure Insert_Str_In_Name_Buffer (S : String; Index : Positive);
419   --  Inserts given string in name buffer, starting at Index. Any existing
420   --  characters at or past this location get moved beyond the inserted string
421   --  and Name_Len is incremented by the length of the string.
422
423   procedure Set_Character_Literal_Name (C : Char_Code);
424   --  This procedure sets the proper encoded name for the character literal
425   --  for the given character code. On return Name_Buffer and Name_Len are
426   --  set to reflect the stored name.
427
428   procedure Set_Name_Table_Info (Id : Name_Id; Val : Int);
429   pragma Inline (Set_Name_Table_Info);
430   --  Sets the Int value associated with the given name
431
432   procedure Set_Name_Table_Byte (Id : Name_Id; Val : Byte);
433   pragma Inline (Set_Name_Table_Byte);
434   --  Sets the Byte value associated with the given name
435
436   procedure Store_Encoded_Character (C : Char_Code);
437   --  Stores given character code at the end of Name_Buffer, updating the
438   --  value in Name_Len appropriately. Lower case letters and digits are
439   --  stored unchanged. Other 8-bit characters are stored using the Uhh
440   --  encoding (hh = hex code), other 16-bit wide character values are stored
441   --  using the Whhhh (hhhh = hex code) encoding, and other 32-bit wide wide
442   --  character values are stored using the WWhhhhhhhh (hhhhhhhh = hex code).
443   --  Note that this procedure does not fold upper case letters (they are
444   --  stored using the Uhh encoding). If folding is required, it must be done
445   --  by the caller prior to the call.
446
447   procedure Tree_Read;
448   --  Initializes internal tables from current tree file using the relevant
449   --  Table.Tree_Read routines. Note that Initialize should not be called if
450   --  Tree_Read is used. Tree_Read includes all necessary initialization.
451
452   procedure Tree_Write;
453   --  Writes out internal tables to current tree file using the relevant
454   --  Table.Tree_Write routines.
455
456   procedure Get_Last_Two_Chars (N : Name_Id; C1, C2 : out Character);
457   --  Obtains last two characters of a name. C1 is last but one character
458   --  and C2 is last character. If name is less than two characters long,
459   --  then both C1 and C2 are set to ASCII.NUL on return.
460
461   procedure Write_Name (Id : Name_Id);
462   --  Write_Name writes the characters of the specified name using the
463   --  standard output procedures in package Output. No end of line is
464   --  written, just the characters of the name. On return Name_Buffer and
465   --  Name_Len are set as for a call to Get_Name_String. The name is written
466   --  in encoded form (i.e. including Uhh, Whhh, Qx, _op as they appear in
467   --  the name table). If Id is Error_Name, or No_Name, no text is output.
468
469   procedure Write_Name_Decoded (Id : Name_Id);
470   --  Like Write_Name, except that the name written is the decoded name, as
471   --  described for Get_Decoded_Name_String, and the resulting value stored
472   --  in Name_Len and Name_Buffer is the decoded name.
473
474   ------------------------------
475   -- File and Unit Name Types --
476   ------------------------------
477
478   --  These are defined here in Namet rather than Fname and Uname to avoid
479   --  problems with dependencies, and to avoid dragging in Fname and Uname
480   --  into many more files, but it would be cleaner to move to Fname/Uname.
481
482   type File_Name_Type is new Name_Id;
483   --  File names are stored in the names table and this type is used to
484   --  indicate that a Name_Id value is being used to hold a simple file name
485   --  (which does not include any directory information).
486
487   No_File : constant File_Name_Type := File_Name_Type (No_Name);
488   --  Constant used to indicate no file is present (this is used for example
489   --  when a search for a file indicates that no file of the name exists).
490
491   Error_File_Name : constant File_Name_Type := File_Name_Type (Error_Name);
492   --  The special File_Name_Type value Error_File_Name is used to indicate
493   --  a unit name where some previous processing has found an error.
494
495   subtype Error_File_Name_Or_No_File is
496     File_Name_Type range No_File .. Error_File_Name;
497   --  Used to test for either error file name or no file
498
499   type Path_Name_Type is new Name_Id;
500   --  Path names are stored in the names table and this type is used to
501   --  indicate that a Name_Id value is being used to hold a path name (that
502   --  may contain directory information).
503
504   No_Path : constant Path_Name_Type := Path_Name_Type (No_Name);
505   --  Constant used to indicate no path name is present
506
507   type Unit_Name_Type is new Name_Id;
508   --  Unit names are stored in the names table and this type is used to
509   --  indicate that a Name_Id value is being used to hold a unit name, which
510   --  terminates in %b for a body or %s for a spec.
511
512   No_Unit_Name : constant Unit_Name_Type := Unit_Name_Type (No_Name);
513   --  Constant used to indicate no file name present
514
515   Error_Unit_Name : constant Unit_Name_Type := Unit_Name_Type (Error_Name);
516   --  The special Unit_Name_Type value Error_Unit_Name is used to indicate
517   --  a unit name where some previous processing has found an error.
518
519   subtype Error_Unit_Name_Or_No_Unit_Name is
520     Unit_Name_Type range No_Unit_Name .. Error_Unit_Name;
521
522   ------------------------
523   -- Debugging Routines --
524   ------------------------
525
526   procedure wn (Id : Name_Id);
527   pragma Export (Ada, wn);
528   --  This routine is intended for debugging use only (i.e. it is intended to
529   --  be called from the debugger). It writes the characters of the specified
530   --  name using the standard output procedures in package Output, followed by
531   --  a new line. The name is written in encoded form (i.e. including Uhh,
532   --  Whhh, Qx, _op as they appear in the name table). If Id is Error_Name,
533   --  No_Name, or invalid an appropriate string is written (<Error_Name>,
534   --  <No_Name>, <invalid name>). Unlike Write_Name, this call does not affect
535   --  the contents of Name_Buffer or Name_Len.
536
537   ---------------------------
538   -- Table Data Structures --
539   ---------------------------
540
541   --  The following declarations define the data structures used to store
542   --  names. The definitions are in the private part of the package spec,
543   --  rather than the body, since they are referenced directly by gigi.
544
545private
546
547   --  This table stores the actual string names. Although logically there is
548   --  no need for a terminating character (since the length is stored in the
549   --  name entry table), we still store a NUL character at the end of every
550   --  name (for convenience in interfacing to the C world).
551
552   package Name_Chars is new Table.Table (
553     Table_Component_Type => Character,
554     Table_Index_Type     => Int,
555     Table_Low_Bound      => 0,
556     Table_Initial        => Alloc.Name_Chars_Initial,
557     Table_Increment      => Alloc.Name_Chars_Increment,
558     Table_Name           => "Name_Chars");
559
560   type Name_Entry is record
561      Name_Chars_Index : Int;
562      --  Starting location of characters in the Name_Chars table minus one
563      --  (i.e. pointer to character just before first character). The reason
564      --  for the bias of one is that indexes in Name_Buffer are one's origin,
565      --  so this avoids unnecessary adds and subtracts of 1.
566
567      Name_Len : Short;
568      --  Length of this name in characters
569
570      Byte_Info : Byte;
571      --  Byte value associated with this name
572
573      Name_Has_No_Encodings : Boolean;
574      --  This flag is set True if the name entry is known not to contain any
575      --  special character encodings. This is used to speed up repeated calls
576      --  to Get_Decoded_Name_String. A value of False means that it is not
577      --  known whether the name contains any such encodings.
578
579      Hash_Link : Name_Id;
580      --  Link to next entry in names table for same hash code
581
582      Int_Info : Int;
583      --  Int Value associated with this name
584   end record;
585
586   for Name_Entry use record
587      Name_Chars_Index      at  0 range 0 .. 31;
588      Name_Len              at  4 range 0 .. 15;
589      Byte_Info             at  6 range 0 .. 7;
590      Name_Has_No_Encodings at  7 range 0 .. 7;
591      Hash_Link             at  8 range 0 .. 31;
592      Int_Info              at 12 range 0 .. 31;
593   end record;
594
595   for Name_Entry'Size use 16 * 8;
596   --  This ensures that we did not leave out any fields
597
598   --  This is the table that is referenced by Name_Id entries.
599   --  It contains one entry for each unique name in the table.
600
601   package Name_Entries is new Table.Table (
602     Table_Component_Type => Name_Entry,
603     Table_Index_Type     => Name_Id'Base,
604     Table_Low_Bound      => First_Name_Id,
605     Table_Initial        => Alloc.Names_Initial,
606     Table_Increment      => Alloc.Names_Increment,
607     Table_Name           => "Name_Entries");
608
609end Namet;
610