gcc/m2/gm2-compiler/M2Bitset.mod

   1 (* M2Bitset.mod provides the BITSET type.
   2
   3 Copyright (C) 2003-2022 Free Software Foundation, Inc.
   4 Contributed by Gaius Mulley <gaius.mulley@southwales.ac.uk>.
   5
   6 This file is part of GNU Modula-2.
   7
   8 GNU Modula-2 is free software; you can redistribute it and/or modify
   9 it under the terms of the GNU General Public License as published by
  10 the Free Software Foundation; either version 3, or (at your option)
  11 any later version.
  12
  13 GNU Modula-2 is distributed in the hope that it will be useful, but
  14 WITHOUT ANY WARRANTY; without even the implied warranty of
  15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16 General Public License for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with GNU Modula-2; see the file COPYING3.  If not see
  20 <http://www.gnu.org/licenses/>.  *)
  21
  22 IMPLEMENTATION MODULE M2Bitset ;
  23
  24
  25 FROM M2Debug IMPORT Assert ;
  26 FROM m2tree IMPORT Tree ;
  27 FROM m2linemap IMPORT BuiltinsLocation ;
  28 FROM m2type IMPORT GetWordType ;
  29 FROM m2decl IMPORT GetBitsPerBitset ;
  30 FROM m2expr IMPORT GetSizeOf ;
  31 FROM M2ALU IMPORT PushCard, PushIntegerTree ;
  32 FROM NameKey IMPORT MakeKey ;
  33 FROM M2System IMPORT Word ;
  34 FROM M2Base IMPORT Cardinal ;
  35 FROM M2LexBuf IMPORT BuiltinTokenNo ;
  36
  37 FROM SymbolTable IMPORT NulSym,
  38                         MakeConstLit,
  39                         MakeConstVar,
  40                         MakeSet,
  41                         MakeSubrange,
  42                         PutSet,
  43                         PutSubrange,
  44                         PopValue,
  45                         PopSize ;
  46
  47
  48 VAR
  49    MinBitset, MaxBitset : CARDINAL ;
  50
  51
  52 (*
  53    MakeBitset - creates and declares the type BITSET.
  54 *)
  55
  56 PROCEDURE MakeBitset ;
  57 BEGIN
  58    Bitset := MakeSet (BuiltinTokenNo, MakeKey('BITSET')) ;     (* Base Type       *)
  59
  60    (* MinBitset *)
  61    MinBitset := MakeConstLit (BuiltinTokenNo, MakeKey('0'), Cardinal) ;
  62
  63    (* MaxBitset *)
  64    MaxBitset := MakeConstVar (BuiltinTokenNo, MakeKey('MaxBitset')) ;
  65    PushCard (GetBitsPerBitset()-1) ;
  66    PopValue (MaxBitset) ;
  67
  68    Assert (Word#NulSym) ;
  69    Bitnum := MakeSubrange (BuiltinTokenNo, MakeKey('BITNUM')) ;
  70    PutSubrange (Bitnum, MinBitset, MaxBitset, Cardinal) ;
  71    PutSet (Bitset, Bitnum, FALSE) ;
  72
  73    PushIntegerTree (GetSizeOf(BuiltinsLocation(), GetWordType())) ;
  74    PopSize (Bitset)
  75 END MakeBitset ;
  76
  77
  78 (*
  79    GetBitsetMinMax - assigns min and max to the minimum and maximum values of BITSET.
  80 *)
  81
  82 PROCEDURE GetBitsetMinMax (VAR min, max: CARDINAL) ;
  83 BEGIN
  84    min := MinBitset ;
  85    max := MaxBitset
  86 END GetBitsetMinMax ;
  87
  88
  89 END M2Bitset.