gcc/m2/gm2-compiler/M2Range.def

   1 (* M2Range.def exports procedures which maintain the range checking.
   2
   3 Copyright (C) 2008-2022 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 DEFINITION MODULE M2Range ;
  23
  24 (*
  25     Title      : M2Range
  26     Author     : Gaius Mulley
  27     System     : GNU Modula-2
  28     Date       : Thu Feb 28 10:18:55 2008
  29     Revision   : $Version$
  30     Description: exports procedures which maintain the range checking
  31                  state which is explored once all the subrange values
  32                  have been resolved by the front end (once
  33                  M2GCCDeclare has completed its task).  We cannot
  34                  perform this activity during M2Quads, as we dont
  35                  know the subrange values and also we can do so much
  36                  more once optimization has occurred.  It should be
  37                  possible to detect simple overflow errors at compile
  38                  time, post optimization.
  39 *)
  40
  41 FROM SYSTEM IMPORT ADDRESS ;
  42 FROM m2tree IMPORT Tree ;
  43 FROM m2linemap IMPORT location_t ;
  44 FROM DynamicStrings IMPORT String ;
  45
  46 EXPORT QUALIFIED InitAssignmentRangeCheck,
  47                  InitReturnRangeCheck,
  48                  InitSubrangeRangeCheck,
  49                  InitStaticArraySubscriptRangeCheck,
  50                  InitDynamicArraySubscriptRangeCheck,
  51                  InitIncRangeCheck,
  52                  InitDecRangeCheck,
  53                  InitInclCheck,
  54                  InitExclCheck,
  55                  InitRotateCheck,
  56                  InitShiftCheck,
  57                  InitTypesExpressionCheck,
  58                  InitTypesAssignmentCheck,
  59                  InitTypesParameterCheck,
  60                  InitParameterRangeCheck,
  61                  InitForLoopBeginRangeCheck,
  62                  InitForLoopToRangeCheck,
  63                  InitForLoopEndRangeCheck,
  64                  InitPointerRangeCheck,
  65                  InitNoReturnRangeCheck,
  66                  InitNoElseRangeCheck,
  67                  InitCaseBounds,
  68                  InitWholeNonPosDivCheck,
  69                  InitWholeNonPosModCheck,
  70                  InitWholeZeroDivisionCheck,
  71                  InitWholeZeroRemainderCheck,
  72                  CodeRangeCheck, FoldRangeCheck, CodeErrorCheck,
  73                  (* CheckRangeAddVariableRead,  *)
  74                  (* CheckRangeRemoveVariableRead,  *)
  75                  WriteRangeCheck,
  76                  OverlapsRange,
  77                  IsEqual, IsGreaterOrEqual, IsGreater,
  78                  BuildIfCallRealHandlerLoc,
  79                  BuildIfCallWholeHandlerLoc,
  80                  GetMinMax ;
  81
  82
  83 (*
  84    InitAssignmentRangeCheck - returns a range check node which
  85                               remembers the information necessary
  86                               so that a range check for d := e
  87                               can be generated later on.
  88 *)
  89
  90 PROCEDURE InitAssignmentRangeCheck (tokno: CARDINAL; d, e: CARDINAL) : CARDINAL ;
  91
  92
  93 (*
  94    InitReturnRangeCheck - returns a range check node which
  95                            remembers the information necessary
  96                            so that a range check for RETURN e
  97                            from procedure, d, can be generated later on.
  98 *)
  99
 100 PROCEDURE InitReturnRangeCheck (tokno: CARDINAL; d, e: CARDINAL) : CARDINAL ;
 101
 102
 103 (*
 104    InitSubrangeRangeCheck - returns a range check node which
 105                             remembers the information necessary
 106                             so that a range check for d := e
 107                             can be generated later on.
 108 *)
 109
 110 PROCEDURE InitSubrangeRangeCheck (d, e: CARDINAL) : CARDINAL ;
 111
 112
 113 (*
 114    InitStaticArraySubscriptRangeCheck - returns a range check node which
 115                                         remembers the information necessary
 116                                         so that a range check for d[e]
 117                                         can be generated later on.
 118 *)
 119
 120 PROCEDURE InitStaticArraySubscriptRangeCheck (d, e, dim: CARDINAL) : CARDINAL ;
 121
 122
 123 (*
 124    InitDynamicArraySubscriptRangeCheck - returns a range check node which
 125                                          remembers the information necessary
 126                                          so that a range check for d[e]
 127                                          can be generated later on.
 128 *)
 129
 130 PROCEDURE InitDynamicArraySubscriptRangeCheck (d, e, dim: CARDINAL) : CARDINAL ;
 131
 132
 133 (*
 134    InitIncRangeCheck - returns a range check node which
 135                        remembers the information necessary
 136                        so that a range check for INC(d, e)
 137                        can be generated later on.
 138 *)
 139
 140 PROCEDURE InitIncRangeCheck (d, e: CARDINAL) : CARDINAL ;
 141
 142
 143 (*
 144    InitDecRangeCheck - returns a range check node which
 145                        remembers the information necessary
 146                        so that a range check for DEC(d, e)
 147                        can be generated later on.
 148 *)
 149
 150 PROCEDURE InitDecRangeCheck (d, e: CARDINAL) : CARDINAL ;
 151
 152
 153 (*
 154    InitForLoopBeginRangeCheck - returns a range check node which
 155                                 remembers the information necessary
 156                                 so that a range check for FOR d := e TO .. DO
 157                                 can be generated later on.
 158 *)
 159
 160 PROCEDURE InitForLoopBeginRangeCheck (d, e: CARDINAL) : CARDINAL ;
 161
 162
 163 (*
 164    InitForLoopToRangeCheck - returns a range check node which
 165                              remembers the information necessary
 166                              so that a range check for the final value
 167                              implied by ... e1 TO e2 BY e3 DO
 168                              can be generated later on.
 169 *)
 170
 171 PROCEDURE InitForLoopToRangeCheck (d, e: CARDINAL) : CARDINAL ;
 172
 173
 174 (*
 175    InitForLoopEndRangeCheck - returns a range check node which
 176                               remembers the information necessary
 177                               so that a range check for
 178                               INC or DEC(d, e)
 179                               can be generated later on.
 180 *)
 181
 182 PROCEDURE InitForLoopEndRangeCheck (d, e: CARDINAL) : CARDINAL ;
 183
 184
 185 (*
 186    InitPointerRangeCheck - creates a pointer # NIL check.
 187 *)
 188
 189 PROCEDURE InitPointerRangeCheck (tokno: CARDINAL;
 190                                  d: CARDINAL; isLeft: BOOLEAN) : CARDINAL ;
 191
 192
 193 (*
 194    InitNoReturnRangeCheck - creates a check held in the function
 195                             to detect the absence of a RETURN
 196                             statement at runtime.
 197 *)
 198
 199 PROCEDURE InitNoReturnRangeCheck () : CARDINAL ;
 200
 201
 202 (*
 203    InitNoElseRangeCheck - creates a check held at the end of
 204                           a CASE statement without an ELSE
 205                           clause to detect its absence
 206                           at runtime.
 207 *)
 208
 209 PROCEDURE InitNoElseRangeCheck () : CARDINAL ;
 210
 211
 212 (*
 213    InitWholeNonPosDivCheck - creates a check expression for non positive
 214                              or zero 2nd operand to division.
 215 *)
 216
 217 PROCEDURE InitWholeNonPosDivCheck (tokno: CARDINAL; d, e: CARDINAL) : CARDINAL ;
 218
 219
 220 (*
 221    InitWholeNonPosModCheck - creates a check expression for non positive
 222                              or zero 2nd operand to modulus.
 223 *)
 224
 225 PROCEDURE InitWholeNonPosModCheck (tokno: CARDINAL; d, e: CARDINAL) : CARDINAL ;
 226
 227
 228 (*
 229    InitWholeZeroDivisionCheck - creates a check expression for zero 2nd
 230                                 operand for division.
 231 *)
 232
 233 PROCEDURE InitWholeZeroDivisionCheck (tokno: CARDINAL; d, e: CARDINAL) : CARDINAL ;
 234
 235
 236 (*
 237    InitWholeZeroRemainderCheck - creates a check expression for zero 2nd
 238                                  operand for remainder.
 239 *)
 240
 241 PROCEDURE InitWholeZeroRemainderCheck (tokno: CARDINAL; d, e: CARDINAL) : CARDINAL ;
 242
 243
 244 (*
 245    InitInclCheck - checks to see that bit, e, is type compatible with
 246                    d and also in range.
 247 *)
 248
 249 PROCEDURE InitInclCheck (d, e: CARDINAL) : CARDINAL ;
 250
 251
 252 (*
 253    InitExclCheck - checks to see that bit, e, is type compatible with
 254                    d and also in range.
 255 *)
 256
 257 PROCEDURE InitExclCheck (d, e: CARDINAL) : CARDINAL ;
 258
 259
 260 (*
 261    InitShiftCheck - checks to see that bit, e, is type compatible with
 262                     d and also in range.
 263 *)
 264
 265 PROCEDURE InitShiftCheck (d, e: CARDINAL) : CARDINAL ;
 266
 267
 268 (*
 269    InitRotateCheck - checks to see that bit, e, is type compatible with
 270                      d and also in range.
 271 *)
 272
 273 PROCEDURE InitRotateCheck (d, e: CARDINAL) : CARDINAL ;
 274
 275
 276 (*
 277    InitTypesAssignmentCheck - checks to see that the types of, d, and, e,
 278                               are assignment compatible.
 279 *)
 280
 281 PROCEDURE InitTypesAssignmentCheck (tokno: CARDINAL; d, e: CARDINAL) : CARDINAL ;
 282
 283
 284 (*
 285    InitTypesParameterCheck - checks to see that the types of, d, and, e,
 286                              are parameter compatible.
 287 *)
 288
 289 PROCEDURE InitTypesParameterCheck (proc: CARDINAL; i: CARDINAL;
 290                                    formal, actual: CARDINAL) : CARDINAL ;
 291
 292
 293 (*
 294    InitParameterRangeCheck - checks to see that the types of, d, and, e,
 295                              are parameter compatible.
 296 *)
 297
 298 PROCEDURE InitParameterRangeCheck (proc: CARDINAL; i: CARDINAL;
 299                                    formal, actual: CARDINAL) : CARDINAL ;
 300
 301
 302 (*
 303    InitTypesExpressionCheck - checks to see that the types of, d, and, e,
 304                               are expression compatible.
 305 *)
 306
 307 PROCEDURE InitTypesExpressionCheck (tokno: CARDINAL; d, e: CARDINAL;
 308                                     strict, isin: BOOLEAN) : CARDINAL ;
 309
 310
 311 (*
 312    InitCaseBounds - creates a case bound range check.
 313 *)
 314
 315 PROCEDURE InitCaseBounds (b: CARDINAL) : CARDINAL ;
 316
 317
 318 (*
 319    CodeRangeCheck - creates a sequence of Trees representing the code for a
 320                     range test defined by, r.
 321 *)
 322
 323 PROCEDURE CodeRangeCheck (r: CARDINAL; function: String) ;
 324
 325
 326 (*
 327    FoldRangeCheck - returns a Tree representing the code for a
 328                     range test defined by, r.
 329 *)
 330
 331 PROCEDURE FoldRangeCheck (tokenno: CARDINAL; q: CARDINAL; r: CARDINAL) ;
 332
 333
 334 (*
 335    CodeErrorCheck - returns a Tree calling the approprate exception handler.
 336 *)
 337
 338 PROCEDURE CodeErrorCheck (r: CARDINAL; function, message: String) : Tree ;
 339
 340
 341 (*
 342    CheckRangeAddVariableRead - ensures that any references to reading
 343                                variables used by this range check, r,
 344                                at this, quadNo, are recorded in the
 345                                symbol table.
 346 *)
 347
 348 (* PROCEDURE CheckRangeAddVariableRead (r: CARDINAL; quadNo: CARDINAL) ; *)
 349
 350
 351 (*
 352    CheckRangeRemoveVariableRead - ensures that any references to reading
 353                                   variable at this quadNo are removed from
 354                                   the symbol table.
 355 *)
 356
 357 (* PROCEDURE CheckRangeRemoveVariableRead (r: CARDINAL; quadNo: CARDINAL) ; *)
 358
 359
 360 (*
 361    WriteRangeCheck - displays debugging information about range, r.
 362 *)
 363
 364 PROCEDURE WriteRangeCheck (r: CARDINAL) ;
 365
 366
 367 (*
 368    OverlapsRange - returns TRUE if a1..a2 overlaps with b1..b2.
 369 *)
 370
 371 PROCEDURE OverlapsRange (a1, a2, b1, b2: Tree) : BOOLEAN ;
 372
 373
 374 (*
 375    IsEqual - returns TRUE if a=b.
 376 *)
 377
 378 PROCEDURE IsEqual (a, b: Tree) : BOOLEAN ;
 379
 380
 381 (*
 382    IsGreaterOrEqual - returns TRUE if a>=b.
 383 *)
 384
 385 PROCEDURE IsGreaterOrEqual (a, b: Tree) : BOOLEAN ;
 386
 387
 388 (*
 389    IsGreater - returns TRUE if a>b.
 390 *)
 391
 392 PROCEDURE IsGreater (a, b: Tree) : BOOLEAN ;
 393
 394
 395 (*
 396    BuildIfCallWholeHandlerLoc - return a Tree containing a runtime test whether, condition, is true.
 397 *)
 398
 399 PROCEDURE BuildIfCallWholeHandlerLoc (location: location_t; condition: Tree;
 400                                       scope, message: ADDRESS) : Tree ;
 401
 402
 403 (*
 404    BuildIfCallRealHandlerLoc - return a Tree containing a runtime test whether, condition, is true.
 405 *)
 406
 407 PROCEDURE BuildIfCallRealHandlerLoc (location: location_t; condition: Tree;
 408                                      scope, message: ADDRESS) : Tree ;
 409
 410
 411 (*
 412    GetMinMax - returns TRUE if we know the max and min of a type, t.
 413 *)
 414
 415 PROCEDURE GetMinMax (tokenno: CARDINAL; type: CARDINAL; VAR min, max: Tree) : BOOLEAN ;
 416
 417
 418 END M2Range.