------------------------------------------------------------------------------
-- --
-- GNAT COMPILER COMPONENTS --
-- --
-- N A M E T --
-- --
-- S p e c --
-- --
-- Copyright (C) 1992-2013, Free Software Foundation, Inc. --
-- --
-- GNAT is free software; you can redistribute it and/or modify it under --
-- terms of the GNU General Public License as published by the Free Soft- --
-- ware Foundation; either version 3, or (at your option) any later ver- --
-- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
-- or FITNESS FOR A PARTICULAR PURPOSE. --
-- --
-- As a special exception under Section 7 of GPL version 3, you are granted --
-- additional permissions described in the GCC Runtime Library Exception, --
-- version 3.1, as published by the Free Software Foundation. --
-- --
-- You should have received a copy of the GNU General Public License and --
-- a copy of the GCC Runtime Library Exception along with this program; --
-- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
-- . --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
-- --
------------------------------------------------------------------------------
with Alloc;
with Table;
with Hostparm; use Hostparm;
with System; use System;
with Types; use Types;
package Namet is
-- WARNING: There is a C version of this package. Any changes to this
-- source file must be properly reflected in the C header file namet.h
-- which is created manually from namet.ads and namet.adb.
-- This package contains routines for handling the names table. The table
-- is used to store character strings for identifiers and operator symbols,
-- as well as other string values such as unit names and file names.
-- The forms of the entries are as follows:
-- Identifiers Stored with upper case letters folded to lower case.
-- Upper half (16#80# bit set) and wide characters are
-- stored in an encoded form (Uhh for upper half char,
-- Whhhh for wide characters, WWhhhhhhhh as provided by
-- the routine Store_Encoded_Character, where hh are hex
-- digits for the character code using lower case a-f).
-- Normally the use of U or W in other internal names is
-- avoided, but these letters may be used in internal
-- names (without this special meaning), if they appear
-- as the last character of the name, or they are
-- followed by an upper case letter (other than the WW
-- sequence), or an underscore.
-- Operator symbols Stored with an initial letter O, and the remainder
-- of the name is the lower case characters XXX where
-- the name is Name_Op_XXX, see Snames spec for a full
-- list of the operator names. Normally the use of O
-- in other internal names is avoided, but it may be
-- used in internal names (without this special meaning)
-- if it is the last character of the name, or if it is
-- followed by an upper case letter or an underscore.
-- Character literals Character literals have names that are used only for
-- debugging and error message purposes. The form is an
-- upper case Q followed by a single lower case letter,
-- or by a Uxx/Wxxxx/WWxxxxxxx encoding as described for
-- identifiers. The Set_Character_Literal_Name procedure
-- should be used to construct these encodings. Normally
-- the use of O in other internal names is avoided, but
-- it may be used in internal names (without this special
-- meaning) if it is the last character of the name, or
-- if it is followed by an upper case letter or an
-- underscore.
-- Unit names Stored with upper case letters folded to lower case,
-- using Uhh/Whhhh/WWhhhhhhhh encoding as described for
-- identifiers, and a %s or %b suffix for specs/bodies.
-- See package Uname for further details.
-- File names Are stored in the form provided by Osint. Typically
-- they may include wide character escape sequences and
-- upper case characters (in non-encoded form). Casing
-- is also derived from the external environment. Note
-- that file names provided by Osint must generally be
-- consistent with the names from Fname.Get_File_Name.
-- Other strings The names table is also used as a convenient storage
-- location for other variable length strings such as
-- error messages etc. There are no restrictions on what
-- characters may appear for such entries.
-- Note: the encodings Uhh (upper half characters), Whhhh (wide characters),
-- WWhhhhhhhh (wide wide characters) and Qx (character literal names) are
-- described in the spec, since they are visible throughout the system (e.g.
-- in debugging output). However, no code should depend on these particular
-- encodings, so it should be possible to change the encodings by making
-- changes only to the Namet specification (to change these comments) and the
-- body (which actually implements the encodings).
-- The names are hashed so that a given name appears only once in the table,
-- except that names entered with Name_Enter as opposed to Name_Find are
-- omitted from the hash table.
-- The first 26 entries in the names table (with Name_Id values in the range
-- First_Name_Id .. First_Name_Id + 25) represent names which are the one
-- character lower case letters in the range a-z, and these names are created
-- and initialized by the Initialize procedure.
-- Two values, one of type Int and one of type Byte, are stored with each
-- names table entry and subprograms are provided for setting and retrieving
-- these associated values. The usage of these values is up to the client. In
-- the compiler, the Int field is used to point to a chain of potentially
-- visible entities (see Sem.Ch8 for details), and the Byte field is used to
-- hold the Token_Type value for reserved words (see Sem for details). In the
-- binder, the Byte field is unused, and the Int field is used in various
-- ways depending on the name involved (see binder documentation).
Name_Buffer : String (1 .. 4 * Max_Line_Length);
-- This buffer is used to set the name to be stored in the table for the
-- Name_Find call, and to retrieve the name for the Get_Name_String call.
-- The limit here is intended to be an infinite value that ensures that we
-- never overflow the buffer (names this long are too absurd to worry).
Name_Len : Natural := 0;
-- Length of name stored in Name_Buffer. Used as an input parameter for
-- Name_Find, and as an output value by Get_Name_String, or Write_Name.
-- Note: in normal usage, all users of Name_Buffer/Name_Len are expected
-- to initialize Name_Len appropriately. The reason we preinitialize to
-- zero here is that some circuitry (e.g. Osint.Write_Program_Name) does
-- a save/restore on Name_Len and Name_Buffer (1 .. Name_Len), and we do
-- not want some arbitrary junk value to result in saving an arbitrarily
-- long slice which would waste time and blow the stack.
-----------------------------
-- Types for Namet Package --
-----------------------------
-- Name_Id values are used to identify entries in the names table. Except
-- for the special values No_Name and Error_Name, they are subscript values
-- for the Names table defined in this package.
-- Note that with only a few exceptions, which are clearly documented, the
-- type Name_Id should be regarded as a private type. In particular it is
-- never appropriate to perform arithmetic operations using this type.
type Name_Id is range Names_Low_Bound .. Names_High_Bound;
for Name_Id'Size use 32;
-- Type used to identify entries in the names table
No_Name : constant Name_Id := Names_Low_Bound;
-- The special Name_Id value No_Name is used in the parser to indicate
-- a situation where no name is present (e.g. on a loop or block).
Error_Name : constant Name_Id := Names_Low_Bound + 1;
-- The special Name_Id value Error_Name is used in the parser to
-- indicate that some kind of error was encountered in scanning out
-- the relevant name, so it does not have a representable label.
subtype Error_Name_Or_No_Name is Name_Id range No_Name .. Error_Name;
-- Used to test for either error name or no name
First_Name_Id : constant Name_Id := Names_Low_Bound + 2;
-- Subscript of first entry in names table
------------------------------
-- Name_Id Membership Tests --
------------------------------
-- The following functions allow a convenient notation for testing whether
-- a Name_Id value matches any one of a list of possible values. In each
-- case True is returned if the given T argument is equal to any of the V
-- arguments. These essentially duplicate the Ada 2012 membership tests,
-- but we cannot use the latter (yet) in the compiler front end, because
-- of bootstrap considerations
function Nam_In
(T : Name_Id;
V1 : Name_Id;
V2 : Name_Id) return Boolean;
function Nam_In
(T : Name_Id;
V1 : Name_Id;
V2 : Name_Id;
V3 : Name_Id) return Boolean;
function Nam_In
(T : Name_Id;
V1 : Name_Id;
V2 : Name_Id;
V3 : Name_Id;
V4 : Name_Id) return Boolean;
function Nam_In
(T : Name_Id;
V1 : Name_Id;
V2 : Name_Id;
V3 : Name_Id;
V4 : Name_Id;
V5 : Name_Id) return Boolean;
function Nam_In
(T : Name_Id;
V1 : Name_Id;
V2 : Name_Id;
V3 : Name_Id;
V4 : Name_Id;
V5 : Name_Id;
V6 : Name_Id) return Boolean;
function Nam_In
(T : Name_Id;
V1 : Name_Id;
V2 : Name_Id;
V3 : Name_Id;
V4 : Name_Id;
V5 : Name_Id;
V6 : Name_Id;
V7 : Name_Id) return Boolean;
pragma Inline (Nam_In);
-- Inline all above functions
-----------------
-- Subprograms --
-----------------
procedure Finalize;
-- Called at the end of a use of the Namet package (before a subsequent
-- call to Initialize). Currently this routine is only used to generate
-- debugging output.
procedure Get_Name_String (Id : Name_Id);
-- Get_Name_String is used to retrieve the string associated with an entry
-- in the names table. The resulting string is stored in Name_Buffer and
-- Name_Len is set. It is an error to call Get_Name_String with one of the
-- special name Id values (No_Name or Error_Name).
function Get_Name_String (Id : Name_Id) return String;
-- This functional form returns the result as a string without affecting
-- the contents of either Name_Buffer or Name_Len. The lower bound is 1.
procedure Get_Unqualified_Name_String (Id : Name_Id);
-- Similar to the above except that qualification (as defined in unit
-- Exp_Dbug) is removed (including both preceding __ delimited names, and
-- also the suffixes used to indicate package body entities and to
-- distinguish between overloaded entities). Note that names are not
-- qualified until just before the call to gigi, so this routine is only
-- needed by processing that occurs after gigi has been called. This
-- includes all ASIS processing, since ASIS works on the tree written
-- after gigi has been called.
procedure Get_Name_String_And_Append (Id : Name_Id);
-- Like Get_Name_String but the resulting characters are appended to the
-- current contents of the entry stored in Name_Buffer, and Name_Len is
-- incremented to include the added characters.
procedure Get_Decoded_Name_String (Id : Name_Id);
-- Same calling sequence an interface as Get_Name_String, except that the
-- result is decoded, so that upper half characters and wide characters
-- appear as originally found in the source program text, operators have
-- their source forms (special characters and enclosed in quotes), and
-- character literals appear surrounded by apostrophes.
procedure Get_Unqualified_Decoded_Name_String (Id : Name_Id);
-- Similar to the above except that qualification (as defined in unit
-- Exp_Dbug) is removed (including both preceding __ delimited names, and
-- also the suffix used to indicate package body entities). Note that
-- names are not qualified until just before the call to gigi, so this
-- routine is only needed by processing that occurs after gigi has been
-- called. This includes all ASIS processing, since ASIS works on the tree
-- written after gigi has been called.
procedure Get_Decoded_Name_String_With_Brackets (Id : Name_Id);
-- This routine is similar to Decoded_Name, except that the brackets
-- notation (Uhh replaced by ["hh"], Whhhh replaced by ["hhhh"],
-- WWhhhhhhhh replaced by ["hhhhhhhh"]) is used for all non-lower half
-- characters, regardless of how Opt.Wide_Character_Encoding_Method is
-- set, and also in that characters in the range 16#80# .. 16#FF# are
-- converted to brackets notation in all cases. This routine can be used
-- when there is a requirement for a canonical representation not affected
-- by the character set options (e.g. in the binder generation of
-- symbols).
function Get_Name_Table_Byte (Id : Name_Id) return Byte;
pragma Inline (Get_Name_Table_Byte);
-- Fetches the Byte value associated with the given name
function Get_Name_Table_Info (Id : Name_Id) return Int;
pragma Inline (Get_Name_Table_Info);
-- Fetches the Int value associated with the given name
function Is_Operator_Name (Id : Name_Id) return Boolean;
-- Returns True if name given is of the form of an operator (that
-- is, it starts with an upper case O).
procedure Initialize;
-- This is a dummy procedure. It is retained for easy compatibility with
-- clients who used to call Initialize when this call was required. Now
-- initialization is performed automatically during package elaboration.
-- Note that this change fixes problems which existed prior to the change
-- of Initialize being called more than once. See also Reinitialize which
-- allows reinitialization of the tables.
procedure Lock;
-- Lock name tables before calling back end. We reserve some extra space
-- before locking to avoid unnecessary inefficiencies when we unlock.
procedure Reinitialize;
-- Clears the name tables and removes all existing entries from the table.
procedure Unlock;
-- Unlocks the name table to allow use of the extra space reserved by the
-- call to Lock. See gnat1drv for details of the need for this.
function Length_Of_Name (Id : Name_Id) return Nat;
pragma Inline (Length_Of_Name);
-- Returns length of given name in characters. This is the length of the
-- encoded name, as stored in the names table, the result is equivalent to
-- calling Get_Name_String and reading Name_Len, except that a call to
-- Length_Of_Name does not affect the contents of Name_Len and Name_Buffer.
function Name_Chars_Address return System.Address;
-- Return starting address of name characters table (used in Back_End call
-- to Gigi).
function Name_Find return Name_Id;
-- Name_Find is called with a string stored in Name_Buffer whose length is
-- in Name_Len (i.e. the characters of the name are in subscript positions
-- 1 to Name_Len in Name_Buffer). It searches the names table to see if
-- the string has already been stored. If so the Id of the existing entry
-- is returned. Otherwise a new entry is created with its Name_Table_Info
-- field set to zero. The contents of Name_Buffer and Name_Len are not
-- modified by this call. Note that it is permissible for Name_Len to be
-- set to zero to lookup the null name string.
function Name_Enter return Name_Id;
-- Name_Enter has the same calling interface as Name_Find. The difference
-- is that it does not search the table for an existing match, and also
-- subsequent Name_Find calls using the same name will not locate the
-- entry created by this call. Thus multiple calls to Name_Enter with the
-- same name will create multiple entries in the name table with different
-- Name_Id values. This is useful in the case of created names, which are
-- never expected to be looked up. Note: Name_Enter should never be used
-- for one character names, since these are efficiently located without
-- hashing by Name_Find in any case.
function Name_Entries_Address return System.Address;
-- Return starting address of Names table (used in Back_End call to Gigi)
function Name_Entries_Count return Nat;
-- Return current number of entries in the names table
function Is_OK_Internal_Letter (C : Character) return Boolean;
pragma Inline (Is_OK_Internal_Letter);
-- Returns true if C is a suitable character for using as a prefix or a
-- suffix of an internally generated name, i.e. it is an upper case letter
-- other than one of the ones used for encoding source names (currently
-- the set of reserved letters is O, Q, U, W) and also returns False for
-- the letter X, which is reserved for debug output (see Exp_Dbug).
function Is_Internal_Name (Id : Name_Id) return Boolean;
-- Returns True if the name is an internal name (i.e. contains a character
-- for which Is_OK_Internal_Letter is true, or if the name starts or ends
-- with an underscore. This call destroys the value of Name_Len and
-- Name_Buffer (it loads these as for Get_Name_String).
--
-- Note: if the name is qualified (has a double underscore), then only the
-- final entity name is considered, not the qualifying names. Consider for
-- example that the name:
--
-- pkg__B_1__xyz
--
-- is not an internal name, because the B comes from the internal name of
-- a qualifying block, but the xyz means that this was indeed a declared
-- identifier called "xyz" within this block and there is nothing internal
-- about that name.
function Is_Internal_Name return Boolean;
-- Like the form with an Id argument, except that the name to be tested is
-- passed in Name_Buffer and Name_Len (which are not affected by the call).
-- Name_Buffer (it loads these as for Get_Name_String).
function Is_Valid_Name (Id : Name_Id) return Boolean;
-- True if Id is a valid name -- points to a valid entry in the
-- Name_Entries table.
procedure Reset_Name_Table;
-- This procedure is used when there are multiple source files to reset
-- the name table info entries associated with current entries in the
-- names table. There is no harm in keeping the names entries themselves
-- from one compilation to another, but we can't keep the entity info,
-- since this refers to tree nodes, which are destroyed between each main
-- source file.
procedure Add_Char_To_Name_Buffer (C : Character);
pragma Inline (Add_Char_To_Name_Buffer);
-- Add given character to the end of the string currently stored in the
-- Name_Buffer, incrementing Name_Len.
procedure Add_Nat_To_Name_Buffer (V : Nat);
-- Add decimal representation of given value to the end of the string
-- currently stored in Name_Buffer, incrementing Name_Len as required.
procedure Add_Str_To_Name_Buffer (S : String);
-- Add characters of string S to the end of the string currently stored
-- in the Name_Buffer, incrementing Name_Len by the length of the string.
procedure Insert_Str_In_Name_Buffer (S : String; Index : Positive);
-- Inserts given string in name buffer, starting at Index. Any existing
-- characters at or past this location get moved beyond the inserted string
-- and Name_Len is incremented by the length of the string.
procedure Set_Character_Literal_Name (C : Char_Code);
-- This procedure sets the proper encoded name for the character literal
-- for the given character code. On return Name_Buffer and Name_Len are
-- set to reflect the stored name.
procedure Set_Name_Table_Info (Id : Name_Id; Val : Int);
pragma Inline (Set_Name_Table_Info);
-- Sets the Int value associated with the given name
procedure Set_Name_Table_Byte (Id : Name_Id; Val : Byte);
pragma Inline (Set_Name_Table_Byte);
-- Sets the Byte value associated with the given name
procedure Store_Encoded_Character (C : Char_Code);
-- Stores given character code at the end of Name_Buffer, updating the
-- value in Name_Len appropriately. Lower case letters and digits are
-- stored unchanged. Other 8-bit characters are stored using the Uhh
-- encoding (hh = hex code), other 16-bit wide character values are stored
-- using the Whhhh (hhhh = hex code) encoding, and other 32-bit wide wide
-- character values are stored using the WWhhhhhhhh (hhhhhhhh = hex code).
-- Note that this procedure does not fold upper case letters (they are
-- stored using the Uhh encoding). If folding is required, it must be done
-- by the caller prior to the call.
procedure Tree_Read;
-- Initializes internal tables from current tree file using the relevant
-- Table.Tree_Read routines. Note that Initialize should not be called if
-- Tree_Read is used. Tree_Read includes all necessary initialization.
procedure Tree_Write;
-- Writes out internal tables to current tree file using the relevant
-- Table.Tree_Write routines.
procedure Get_Last_Two_Chars (N : Name_Id; C1, C2 : out Character);
-- Obtains last two characters of a name. C1 is last but one character
-- and C2 is last character. If name is less than two characters long,
-- then both C1 and C2 are set to ASCII.NUL on return.
procedure Write_Name (Id : Name_Id);
-- Write_Name writes the characters of the specified name using the
-- standard output procedures in package Output. No end of line is
-- written, just the characters of the name. On return Name_Buffer and
-- Name_Len are set as for a call to Get_Name_String. The name is written
-- in encoded form (i.e. including Uhh, Whhh, Qx, _op as they appear in
-- the name table). If Id is Error_Name, or No_Name, no text is output.
procedure Write_Name_Decoded (Id : Name_Id);
-- Like Write_Name, except that the name written is the decoded name, as
-- described for Get_Decoded_Name_String, and the resulting value stored
-- in Name_Len and Name_Buffer is the decoded name.
------------------------------
-- File and Unit Name Types --
------------------------------
-- These are defined here in Namet rather than Fname and Uname to avoid
-- problems with dependencies, and to avoid dragging in Fname and Uname
-- into many more files, but it would be cleaner to move to Fname/Uname.
type File_Name_Type is new Name_Id;
-- File names are stored in the names table and this type is used to
-- indicate that a Name_Id value is being used to hold a simple file name
-- (which does not include any directory information).
No_File : constant File_Name_Type := File_Name_Type (No_Name);
-- Constant used to indicate no file is present (this is used for example
-- when a search for a file indicates that no file of the name exists).
Error_File_Name : constant File_Name_Type := File_Name_Type (Error_Name);
-- The special File_Name_Type value Error_File_Name is used to indicate
-- a unit name where some previous processing has found an error.
subtype Error_File_Name_Or_No_File is
File_Name_Type range No_File .. Error_File_Name;
-- Used to test for either error file name or no file
type Path_Name_Type is new Name_Id;
-- Path names are stored in the names table and this type is used to
-- indicate that a Name_Id value is being used to hold a path name (that
-- may contain directory information).
No_Path : constant Path_Name_Type := Path_Name_Type (No_Name);
-- Constant used to indicate no path name is present
type Unit_Name_Type is new Name_Id;
-- Unit names are stored in the names table and this type is used to
-- indicate that a Name_Id value is being used to hold a unit name, which
-- terminates in %b for a body or %s for a spec.
No_Unit_Name : constant Unit_Name_Type := Unit_Name_Type (No_Name);
-- Constant used to indicate no file name present
Error_Unit_Name : constant Unit_Name_Type := Unit_Name_Type (Error_Name);
-- The special Unit_Name_Type value Error_Unit_Name is used to indicate
-- a unit name where some previous processing has found an error.
subtype Error_Unit_Name_Or_No_Unit_Name is
Unit_Name_Type range No_Unit_Name .. Error_Unit_Name;
------------------------
-- Debugging Routines --
------------------------
procedure wn (Id : Name_Id);
pragma Export (Ada, wn);
-- This routine is intended for debugging use only (i.e. it is intended to
-- be called from the debugger). It writes the characters of the specified
-- name using the standard output procedures in package Output, followed by
-- a new line. The name is written in encoded form (i.e. including Uhh,
-- Whhh, Qx, _op as they appear in the name table). If Id is Error_Name,
-- No_Name, or invalid an appropriate string is written (,
-- , ). Unlike Write_Name, this call does not affect
-- the contents of Name_Buffer or Name_Len.
---------------------------
-- Table Data Structures --
---------------------------
-- The following declarations define the data structures used to store
-- names. The definitions are in the private part of the package spec,
-- rather than the body, since they are referenced directly by gigi.
private
-- This table stores the actual string names. Although logically there is
-- no need for a terminating character (since the length is stored in the
-- name entry table), we still store a NUL character at the end of every
-- name (for convenience in interfacing to the C world).
package Name_Chars is new Table.Table (
Table_Component_Type => Character,
Table_Index_Type => Int,
Table_Low_Bound => 0,
Table_Initial => Alloc.Name_Chars_Initial,
Table_Increment => Alloc.Name_Chars_Increment,
Table_Name => "Name_Chars");
type Name_Entry is record
Name_Chars_Index : Int;
-- Starting location of characters in the Name_Chars table minus one
-- (i.e. pointer to character just before first character). The reason
-- for the bias of one is that indexes in Name_Buffer are one's origin,
-- so this avoids unnecessary adds and subtracts of 1.
Name_Len : Short;
-- Length of this name in characters
Byte_Info : Byte;
-- Byte value associated with this name
Name_Has_No_Encodings : Boolean;
-- This flag is set True if the name entry is known not to contain any
-- special character encodings. This is used to speed up repeated calls
-- to Get_Decoded_Name_String. A value of False means that it is not
-- known whether the name contains any such encodings.
Hash_Link : Name_Id;
-- Link to next entry in names table for same hash code
Int_Info : Int;
-- Int Value associated with this name
end record;
for Name_Entry use record
Name_Chars_Index at 0 range 0 .. 31;
Name_Len at 4 range 0 .. 15;
Byte_Info at 6 range 0 .. 7;
Name_Has_No_Encodings at 7 range 0 .. 7;
Hash_Link at 8 range 0 .. 31;
Int_Info at 12 range 0 .. 31;
end record;
for Name_Entry'Size use 16 * 8;
-- This ensures that we did not leave out any fields
-- This is the table that is referenced by Name_Id entries.
-- It contains one entry for each unique name in the table.
package Name_Entries is new Table.Table (
Table_Component_Type => Name_Entry,
Table_Index_Type => Name_Id'Base,
Table_Low_Bound => First_Name_Id,
Table_Initial => Alloc.Names_Initial,
Table_Increment => Alloc.Names_Increment,
Table_Name => "Name_Entries");
end Namet;