gdb/m2-exp.y

   1 /* YACC grammar for Modula-2 expressions, for GDB.
   2    Copyright (C) 1986, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1999,
   3    2000, 2007, 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
   4    Generated from expread.y (now c-exp.y) and contributed by the Department
   5    of Computer Science at the State University of New York at Buffalo, 1991.
   6
   7    This file is part of GDB.
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  21
  22 /* Parse a Modula-2 expression from text in a string,
  23    and return the result as a  struct expression  pointer.
  24    That structure contains arithmetic operations in reverse polish,
  25    with constants represented by operations that are followed by special data.
  26    See expression.h for the details of the format.
  27    What is important here is that it can be built up sequentially
  28    during the process of parsing; the lower levels of the tree always
  29    come first in the result.
  30
  31    Note that malloc's and realloc's in this file are transformed to
  32    xmalloc and xrealloc respectively by the same sed command in the
  33    makefile that remaps any other malloc/realloc inserted by the parser
  34    generator.  Doing this with #defines and trying to control the interaction
  35    with include files (<malloc.h> and <stdlib.h> for example) just became
  36    too messy, particularly when such includes can be inserted at random
  37    times by the parser generator. */
  38
  39 %{
  40
  41 #include "defs.h"
  42 #include "gdb_string.h"
  43 #include "expression.h"
  44 #include "language.h"
  45 #include "value.h"
  46 #include "parser-defs.h"
  47 #include "m2-lang.h"
  48 #include "bfd.h" /* Required by objfiles.h.  */
  49 #include "symfile.h" /* Required by objfiles.h.  */
  50 #include "objfiles.h" /* For have_full_symbols and have_partial_symbols */
  51 #include "block.h"
  52
  53 #define parse_type builtin_type (parse_gdbarch)
  54 #define parse_m2_type builtin_m2_type (parse_gdbarch)
  55
  56 /* Remap normal yacc parser interface names (yyparse, yylex, yyerror, etc),
  57    as well as gratuitiously global symbol names, so we can have multiple
  58    yacc generated parsers in gdb.  Note that these are only the variables
  59    produced by yacc.  If other parser generators (bison, byacc, etc) produce
  60    additional global names that conflict at link time, then those parser
  61    generators need to be fixed instead of adding those names to this list. */
  62
  63 #define yymaxdepth m2_maxdepth
  64 #define yyparse m2_parse
  65 #define yylex   m2_lex
  66 #define yyerror m2_error
  67 #define yylval  m2_lval
  68 #define yychar  m2_char
  69 #define yydebug m2_debug
  70 #define yypact  m2_pact
  71 #define yyr1    m2_r1
  72 #define yyr2    m2_r2
  73 #define yydef   m2_def
  74 #define yychk   m2_chk
  75 #define yypgo   m2_pgo
  76 #define yyact   m2_act
  77 #define yyexca  m2_exca
  78 #define yyerrflag m2_errflag
  79 #define yynerrs m2_nerrs
  80 #define yyps    m2_ps
  81 #define yypv    m2_pv
  82 #define yys     m2_s
  83 #define yy_yys  m2_yys
  84 #define yystate m2_state
  85 #define yytmp   m2_tmp
  86 #define yyv     m2_v
  87 #define yy_yyv  m2_yyv
  88 #define yyval   m2_val
  89 #define yylloc  m2_lloc
  90 #define yyreds  m2_reds         /* With YYDEBUG defined */
  91 #define yytoks  m2_toks         /* With YYDEBUG defined */
  92 #define yyname  m2_name         /* With YYDEBUG defined */
  93 #define yyrule  m2_rule         /* With YYDEBUG defined */
  94 #define yylhs   m2_yylhs
  95 #define yylen   m2_yylen
  96 #define yydefred m2_yydefred
  97 #define yydgoto m2_yydgoto
  98 #define yysindex m2_yysindex
  99 #define yyrindex m2_yyrindex
 100 #define yygindex m2_yygindex
 101 #define yytable  m2_yytable
 102 #define yycheck  m2_yycheck
 103
 104 #ifndef YYDEBUG
 105 #define YYDEBUG 1               /* Default to yydebug support */
 106 #endif
 107
 108 #define YYFPRINTF parser_fprintf
 109
 110 int yyparse (void);
 111
 112 static int yylex (void);
 113
 114 void yyerror (char *);
 115
 116 #if 0
 117 static char *make_qualname (char *, char *);
 118 #endif
 119
 120 static int parse_number (int);
 121
 122 /* The sign of the number being parsed. */
 123 static int number_sign = 1;
 124
 125 /* The block that the module specified by the qualifer on an identifer is
 126    contained in, */
 127 #if 0
 128 static struct block *modblock=0;
 129 #endif
 130
 131 %}
 132
 133 /* Although the yacc "value" of an expression is not used,
 134    since the result is stored in the structure being created,
 135    other node types do have values.  */
 136
 137 %union
 138   {
 139     LONGEST lval;
 140     ULONGEST ulval;
 141     DOUBLEST dval;
 142     struct symbol *sym;
 143     struct type *tval;
 144     struct stoken sval;
 145     int voidval;
 146     struct block *bval;
 147     enum exp_opcode opcode;
 148     struct internalvar *ivar;
 149
 150     struct type **tvec;
 151     int *ivec;
 152   }
 153
 154 %type <voidval> exp type_exp start set
 155 %type <voidval> variable
 156 %type <tval> type
 157 %type <bval> block
 158 %type <sym> fblock
 159
 160 %token <lval> INT HEX ERROR
 161 %token <ulval> UINT M2_TRUE M2_FALSE CHAR
 162 %token <dval> FLOAT
 163
 164 /* Both NAME and TYPENAME tokens represent symbols in the input,
 165    and both convey their data as strings.
 166    But a TYPENAME is a string that happens to be defined as a typedef
 167    or builtin type name (such as int or char)
 168    and a NAME is any other symbol.
 169
 170    Contexts where this distinction is not important can use the
 171    nonterminal "name", which matches either NAME or TYPENAME.  */
 172
 173 %token <sval> STRING
 174 %token <sval> NAME BLOCKNAME IDENT VARNAME
 175 %token <sval> TYPENAME
 176
 177 %token SIZE CAP ORD HIGH ABS MIN_FUNC MAX_FUNC FLOAT_FUNC VAL CHR ODD TRUNC
 178 %token TSIZE
 179 %token INC DEC INCL EXCL
 180
 181 /* The GDB scope operator */
 182 %token COLONCOLON
 183
 184 %token <voidval> INTERNAL_VAR
 185
 186 /* M2 tokens */
 187 %left ','
 188 %left ABOVE_COMMA
 189 %nonassoc ASSIGN
 190 %left '<' '>' LEQ GEQ '=' NOTEQUAL '#' IN
 191 %left OROR
 192 %left LOGICAL_AND '&'
 193 %left '@'
 194 %left '+' '-'
 195 %left '*' '/' DIV MOD
 196 %right UNARY
 197 %right '^' DOT '[' '('
 198 %right NOT '~'
 199 %left COLONCOLON QID
 200 /* This is not an actual token ; it is used for precedence.
 201 %right QID
 202 */
 203
 204 \f
 205 %%
 206
 207 start   :       exp
 208         |       type_exp
 209         ;
 210
 211 type_exp:       type
 212                 { write_exp_elt_opcode(OP_TYPE);
 213                   write_exp_elt_type($1);
 214                   write_exp_elt_opcode(OP_TYPE);
 215                 }
 216         ;
 217
 218 /* Expressions */
 219
 220 exp     :       exp '^'   %prec UNARY
 221                         { write_exp_elt_opcode (UNOP_IND); }
 222         ;
 223
 224 exp     :       '-'
 225                         { number_sign = -1; }
 226                 exp    %prec UNARY
 227                         { number_sign = 1;
 228                           write_exp_elt_opcode (UNOP_NEG); }
 229         ;
 230
 231 exp     :       '+' exp    %prec UNARY
 232                 { write_exp_elt_opcode(UNOP_PLUS); }
 233         ;
 234
 235 exp     :       not_exp exp %prec UNARY
 236                         { write_exp_elt_opcode (UNOP_LOGICAL_NOT); }
 237         ;
 238
 239 not_exp :       NOT
 240         |       '~'
 241         ;
 242
 243 exp     :       CAP '(' exp ')'
 244                         { write_exp_elt_opcode (UNOP_CAP); }
 245         ;
 246
 247 exp     :       ORD '(' exp ')'
 248                         { write_exp_elt_opcode (UNOP_ORD); }
 249         ;
 250
 251 exp     :       ABS '(' exp ')'
 252                         { write_exp_elt_opcode (UNOP_ABS); }
 253         ;
 254
 255 exp     :       HIGH '(' exp ')'
 256                         { write_exp_elt_opcode (UNOP_HIGH); }
 257         ;
 258
 259 exp     :       MIN_FUNC '(' type ')'
 260                         { write_exp_elt_opcode (UNOP_MIN);
 261                           write_exp_elt_type ($3);
 262                           write_exp_elt_opcode (UNOP_MIN); }
 263         ;
 264
 265 exp     :       MAX_FUNC '(' type ')'
 266                         { write_exp_elt_opcode (UNOP_MAX);
 267                           write_exp_elt_type ($3);
 268                           write_exp_elt_opcode (UNOP_MAX); }
 269         ;
 270
 271 exp     :       FLOAT_FUNC '(' exp ')'
 272                         { write_exp_elt_opcode (UNOP_FLOAT); }
 273         ;
 274
 275 exp     :       VAL '(' type ',' exp ')'
 276                         { write_exp_elt_opcode (BINOP_VAL);
 277                           write_exp_elt_type ($3);
 278                           write_exp_elt_opcode (BINOP_VAL); }
 279         ;
 280
 281 exp     :       CHR '(' exp ')'
 282                         { write_exp_elt_opcode (UNOP_CHR); }
 283         ;
 284
 285 exp     :       ODD '(' exp ')'
 286                         { write_exp_elt_opcode (UNOP_ODD); }
 287         ;
 288
 289 exp     :       TRUNC '(' exp ')'
 290                         { write_exp_elt_opcode (UNOP_TRUNC); }
 291         ;
 292
 293 exp     :       TSIZE '(' exp ')'
 294                         { write_exp_elt_opcode (UNOP_SIZEOF); }
 295         ;
 296
 297 exp     :       SIZE exp       %prec UNARY
 298                         { write_exp_elt_opcode (UNOP_SIZEOF); }
 299         ;
 300
 301
 302 exp     :       INC '(' exp ')'
 303                         { write_exp_elt_opcode(UNOP_PREINCREMENT); }
 304         ;
 305
 306 exp     :       INC '(' exp ',' exp ')'
 307                         { write_exp_elt_opcode(BINOP_ASSIGN_MODIFY);
 308                           write_exp_elt_opcode(BINOP_ADD);
 309                           write_exp_elt_opcode(BINOP_ASSIGN_MODIFY); }
 310         ;
 311
 312 exp     :       DEC '(' exp ')'
 313                         { write_exp_elt_opcode(UNOP_PREDECREMENT);}
 314         ;
 315
 316 exp     :       DEC '(' exp ',' exp ')'
 317                         { write_exp_elt_opcode(BINOP_ASSIGN_MODIFY);
 318                           write_exp_elt_opcode(BINOP_SUB);
 319                           write_exp_elt_opcode(BINOP_ASSIGN_MODIFY); }
 320         ;
 321
 322 exp     :       exp DOT NAME
 323                         { write_exp_elt_opcode (STRUCTOP_STRUCT);
 324                           write_exp_string ($3);
 325                           write_exp_elt_opcode (STRUCTOP_STRUCT); }
 326         ;
 327
 328 exp     :       set
 329         ;
 330
 331 exp     :       exp IN set
 332                         { error("Sets are not implemented.");}
 333         ;
 334
 335 exp     :       INCL '(' exp ',' exp ')'
 336                         { error("Sets are not implemented.");}
 337         ;
 338
 339 exp     :       EXCL '(' exp ',' exp ')'
 340                         { error("Sets are not implemented.");}
 341         ;
 342
 343 set     :       '{' arglist '}'
 344                         { error("Sets are not implemented.");}
 345         |       type '{' arglist '}'
 346                         { error("Sets are not implemented.");}
 347         ;
 348
 349
 350 /* Modula-2 array subscript notation [a,b,c...] */
 351 exp     :       exp '['
 352                         /* This function just saves the number of arguments
 353                            that follow in the list.  It is *not* specific to
 354                            function types */
 355                         { start_arglist(); }
 356                 non_empty_arglist ']'  %prec DOT
 357                         { write_exp_elt_opcode (MULTI_SUBSCRIPT);
 358                           write_exp_elt_longcst ((LONGEST) end_arglist());
 359                           write_exp_elt_opcode (MULTI_SUBSCRIPT); }
 360         ;
 361
 362 exp     :       exp '[' exp ']'
 363                         { write_exp_elt_opcode (BINOP_SUBSCRIPT); }
 364         ;
 365
 366 exp     :       exp '('
 367                         /* This is to save the value of arglist_len
 368                            being accumulated by an outer function call.  */
 369                         { start_arglist (); }
 370                 arglist ')'     %prec DOT
 371                         { write_exp_elt_opcode (OP_FUNCALL);
 372                           write_exp_elt_longcst ((LONGEST) end_arglist ());
 373                           write_exp_elt_opcode (OP_FUNCALL); }
 374         ;
 375
 376 arglist :
 377         ;
 378
 379 arglist :       exp
 380                         { arglist_len = 1; }
 381         ;
 382
 383 arglist :       arglist ',' exp   %prec ABOVE_COMMA
 384                         { arglist_len++; }
 385         ;
 386
 387 non_empty_arglist
 388         :       exp
 389                         { arglist_len = 1; }
 390         ;
 391
 392 non_empty_arglist
 393         :       non_empty_arglist ',' exp %prec ABOVE_COMMA
 394                         { arglist_len++; }
 395         ;
 396
 397 /* GDB construct */
 398 exp     :       '{' type '}' exp  %prec UNARY
 399                         { write_exp_elt_opcode (UNOP_MEMVAL);
 400                           write_exp_elt_type ($2);
 401                           write_exp_elt_opcode (UNOP_MEMVAL); }
 402         ;
 403
 404 exp     :       type '(' exp ')' %prec UNARY
 405                         { write_exp_elt_opcode (UNOP_CAST);
 406                           write_exp_elt_type ($1);
 407                           write_exp_elt_opcode (UNOP_CAST); }
 408         ;
 409
 410 exp     :       '(' exp ')'
 411                         { }
 412         ;
 413
 414 /* Binary operators in order of decreasing precedence.  Note that some
 415    of these operators are overloaded!  (ie. sets) */
 416
 417 /* GDB construct */
 418 exp     :       exp '@' exp
 419                         { write_exp_elt_opcode (BINOP_REPEAT); }
 420         ;
 421
 422 exp     :       exp '*' exp
 423                         { write_exp_elt_opcode (BINOP_MUL); }
 424         ;
 425
 426 exp     :       exp '/' exp
 427                         { write_exp_elt_opcode (BINOP_DIV); }
 428         ;
 429
 430 exp     :       exp DIV exp
 431                         { write_exp_elt_opcode (BINOP_INTDIV); }
 432         ;
 433
 434 exp     :       exp MOD exp
 435                         { write_exp_elt_opcode (BINOP_REM); }
 436         ;
 437
 438 exp     :       exp '+' exp
 439                         { write_exp_elt_opcode (BINOP_ADD); }
 440         ;
 441
 442 exp     :       exp '-' exp
 443                         { write_exp_elt_opcode (BINOP_SUB); }
 444         ;
 445
 446 exp     :       exp '=' exp
 447                         { write_exp_elt_opcode (BINOP_EQUAL); }
 448         ;
 449
 450 exp     :       exp NOTEQUAL exp
 451                         { write_exp_elt_opcode (BINOP_NOTEQUAL); }
 452         |       exp '#' exp
 453                         { write_exp_elt_opcode (BINOP_NOTEQUAL); }
 454         ;
 455
 456 exp     :       exp LEQ exp
 457                         { write_exp_elt_opcode (BINOP_LEQ); }
 458         ;
 459
 460 exp     :       exp GEQ exp
 461                         { write_exp_elt_opcode (BINOP_GEQ); }
 462         ;
 463
 464 exp     :       exp '<' exp
 465                         { write_exp_elt_opcode (BINOP_LESS); }
 466         ;
 467
 468 exp     :       exp '>' exp
 469                         { write_exp_elt_opcode (BINOP_GTR); }
 470         ;
 471
 472 exp     :       exp LOGICAL_AND exp
 473                         { write_exp_elt_opcode (BINOP_LOGICAL_AND); }
 474         ;
 475
 476 exp     :       exp OROR exp
 477                         { write_exp_elt_opcode (BINOP_LOGICAL_OR); }
 478         ;
 479
 480 exp     :       exp ASSIGN exp
 481                         { write_exp_elt_opcode (BINOP_ASSIGN); }
 482         ;
 483
 484
 485 /* Constants */
 486
 487 exp     :       M2_TRUE
 488                         { write_exp_elt_opcode (OP_BOOL);
 489                           write_exp_elt_longcst ((LONGEST) $1);
 490                           write_exp_elt_opcode (OP_BOOL); }
 491         ;
 492
 493 exp     :       M2_FALSE
 494                         { write_exp_elt_opcode (OP_BOOL);
 495                           write_exp_elt_longcst ((LONGEST) $1);
 496                           write_exp_elt_opcode (OP_BOOL); }
 497         ;
 498
 499 exp     :       INT
 500                         { write_exp_elt_opcode (OP_LONG);
 501                           write_exp_elt_type (parse_m2_type->builtin_int);
 502                           write_exp_elt_longcst ((LONGEST) $1);
 503                           write_exp_elt_opcode (OP_LONG); }
 504         ;
 505
 506 exp     :       UINT
 507                         {
 508                           write_exp_elt_opcode (OP_LONG);
 509                           write_exp_elt_type (parse_m2_type->builtin_card);
 510                           write_exp_elt_longcst ((LONGEST) $1);
 511                           write_exp_elt_opcode (OP_LONG);
 512                         }
 513         ;
 514
 515 exp     :       CHAR
 516                         { write_exp_elt_opcode (OP_LONG);
 517                           write_exp_elt_type (parse_m2_type->builtin_char);
 518                           write_exp_elt_longcst ((LONGEST) $1);
 519                           write_exp_elt_opcode (OP_LONG); }
 520         ;
 521
 522
 523 exp     :       FLOAT
 524                         { write_exp_elt_opcode (OP_DOUBLE);
 525                           write_exp_elt_type (parse_m2_type->builtin_real);
 526                           write_exp_elt_dblcst ($1);
 527                           write_exp_elt_opcode (OP_DOUBLE); }
 528         ;
 529
 530 exp     :       variable
 531         ;
 532
 533 exp     :       SIZE '(' type ')'       %prec UNARY
 534                         { write_exp_elt_opcode (OP_LONG);
 535                           write_exp_elt_type (parse_type->builtin_int);
 536                           write_exp_elt_longcst ((LONGEST) TYPE_LENGTH ($3));
 537                           write_exp_elt_opcode (OP_LONG); }
 538         ;
 539
 540 exp     :       STRING
 541                         { write_exp_elt_opcode (OP_M2_STRING);
 542                           write_exp_string ($1);
 543                           write_exp_elt_opcode (OP_M2_STRING); }
 544         ;
 545
 546 /* This will be used for extensions later.  Like adding modules. */
 547 block   :       fblock
 548                         { $$ = SYMBOL_BLOCK_VALUE($1); }
 549         ;
 550
 551 fblock  :       BLOCKNAME
 552                         { struct symbol *sym
 553                             = lookup_symbol (copy_name ($1), expression_context_block,
 554                                              VAR_DOMAIN, 0);
 555                           $$ = sym;}
 556         ;
 557
 558
 559 /* GDB scope operator */
 560 fblock  :       block COLONCOLON BLOCKNAME
 561                         { struct symbol *tem
 562                             = lookup_symbol (copy_name ($3), $1,
 563                                              VAR_DOMAIN, 0);
 564                           if (!tem || SYMBOL_CLASS (tem) != LOC_BLOCK)
 565                             error ("No function \"%s\" in specified context.",
 566                                    copy_name ($3));
 567                           $$ = tem;
 568                         }
 569         ;
 570
 571 /* Useful for assigning to PROCEDURE variables */
 572 variable:       fblock
 573                         { write_exp_elt_opcode(OP_VAR_VALUE);
 574                           write_exp_elt_block (NULL);
 575                           write_exp_elt_sym ($1);
 576                           write_exp_elt_opcode (OP_VAR_VALUE); }
 577         ;
 578
 579 /* GDB internal ($foo) variable */
 580 variable:       INTERNAL_VAR
 581         ;
 582
 583 /* GDB scope operator */
 584 variable:       block COLONCOLON NAME
 585                         { struct symbol *sym;
 586                           sym = lookup_symbol (copy_name ($3), $1,
 587                                                VAR_DOMAIN, 0);
 588                           if (sym == 0)
 589                             error ("No symbol \"%s\" in specified context.",
 590                                    copy_name ($3));
 591
 592                           write_exp_elt_opcode (OP_VAR_VALUE);
 593                           /* block_found is set by lookup_symbol.  */
 594                           write_exp_elt_block (block_found);
 595                           write_exp_elt_sym (sym);
 596                           write_exp_elt_opcode (OP_VAR_VALUE); }
 597         ;
 598
 599 /* Base case for variables. */
 600 variable:       NAME
 601                         { struct symbol *sym;
 602                           int is_a_field_of_this;
 603
 604                           sym = lookup_symbol (copy_name ($1),
 605                                                expression_context_block,
 606                                                VAR_DOMAIN,
 607                                                &is_a_field_of_this);
 608                           if (sym)
 609                             {
 610                               if (symbol_read_needs_frame (sym))
 611                                 {
 612                                   if (innermost_block == 0 ||
 613                                       contained_in (block_found,
 614                                                     innermost_block))
 615                                     innermost_block = block_found;
 616                                 }
 617
 618                               write_exp_elt_opcode (OP_VAR_VALUE);
 619                               /* We want to use the selected frame, not
 620                                  another more inner frame which happens to
 621                                  be in the same block.  */
 622                               write_exp_elt_block (NULL);
 623                               write_exp_elt_sym (sym);
 624                               write_exp_elt_opcode (OP_VAR_VALUE);
 625                             }
 626                           else
 627                             {
 628                               struct minimal_symbol *msymbol;
 629                               char *arg = copy_name ($1);
 630
 631                               msymbol =
 632                                 lookup_minimal_symbol (arg, NULL, NULL);
 633                               if (msymbol != NULL)
 634                                 write_exp_msymbol (msymbol);
 635                               else if (!have_full_symbols () && !have_partial_symbols ())
 636                                 error ("No symbol table is loaded.  Use the \"symbol-file\" command.");
 637                               else
 638                                 error ("No symbol \"%s\" in current context.",
 639                                        copy_name ($1));
 640                             }
 641                         }
 642         ;
 643
 644 type
 645         :       TYPENAME
 646                         { $$ = lookup_typename (parse_language, parse_gdbarch,
 647                                                 copy_name ($1),
 648                                                 expression_context_block, 0); }
 649
 650         ;
 651
 652 %%
 653
 654 /* Take care of parsing a number (anything that starts with a digit).
 655    Set yylval and return the token type; update lexptr.
 656    LEN is the number of characters in it.  */
 657
 658 /*** Needs some error checking for the float case ***/
 659
 660 static int
 661 parse_number (olen)
 662      int olen;
 663 {
 664   char *p = lexptr;
 665   LONGEST n = 0;
 666   LONGEST prevn = 0;
 667   int c,i,ischar=0;
 668   int base = input_radix;
 669   int len = olen;
 670   int unsigned_p = number_sign == 1 ? 1 : 0;
 671
 672   if(p[len-1] == 'H')
 673   {
 674      base = 16;
 675      len--;
 676   }
 677   else if(p[len-1] == 'C' || p[len-1] == 'B')
 678   {
 679      base = 8;
 680      ischar = p[len-1] == 'C';
 681      len--;
 682   }
 683
 684   /* Scan the number */
 685   for (c = 0; c < len; c++)
 686   {
 687     if (p[c] == '.' && base == 10)
 688       {
 689         /* It's a float since it contains a point.  */
 690         yylval.dval = atof (p);
 691         lexptr += len;
 692         return FLOAT;
 693       }
 694     if (p[c] == '.' && base != 10)
 695        error("Floating point numbers must be base 10.");
 696     if (base == 10 && (p[c] < '0' || p[c] > '9'))
 697        error("Invalid digit \'%c\' in number.",p[c]);
 698  }
 699
 700   while (len-- > 0)
 701     {
 702       c = *p++;
 703       n *= base;
 704       if( base == 8 && (c == '8' || c == '9'))
 705          error("Invalid digit \'%c\' in octal number.",c);
 706       if (c >= '0' && c <= '9')
 707         i = c - '0';
 708       else
 709         {
 710           if (base == 16 && c >= 'A' && c <= 'F')
 711             i = c - 'A' + 10;
 712           else
 713              return ERROR;
 714         }
 715       n+=i;
 716       if(i >= base)
 717          return ERROR;
 718       if(!unsigned_p && number_sign == 1 && (prevn >= n))
 719          unsigned_p=1;          /* Try something unsigned */
 720       /* Don't do the range check if n==i and i==0, since that special
 721          case will give an overflow error. */
 722       if(RANGE_CHECK && n!=i && i)
 723       {
 724          if((unsigned_p && (unsigned)prevn >= (unsigned)n) ||
 725             ((!unsigned_p && number_sign==-1) && -prevn <= -n))
 726             range_error("Overflow on numeric constant.");
 727       }
 728          prevn=n;
 729     }
 730
 731   lexptr = p;
 732   if(*p == 'B' || *p == 'C' || *p == 'H')
 733      lexptr++;                  /* Advance past B,C or H */
 734
 735   if (ischar)
 736   {
 737      yylval.ulval = n;
 738      return CHAR;
 739   }
 740   else if ( unsigned_p && number_sign == 1)
 741   {
 742      yylval.ulval = n;
 743      return UINT;
 744   }
 745   else if((unsigned_p && (n<0))) {
 746      range_error("Overflow on numeric constant -- number too large.");
 747      /* But, this can return if range_check == range_warn.  */
 748   }
 749   yylval.lval = n;
 750   return INT;
 751 }
 752
 753
 754 /* Some tokens */
 755
 756 static struct
 757 {
 758    char name[2];
 759    int token;
 760 } tokentab2[] =
 761 {
 762     { {'<', '>'},    NOTEQUAL   },
 763     { {':', '='},    ASSIGN     },
 764     { {'<', '='},    LEQ        },
 765     { {'>', '='},    GEQ        },
 766     { {':', ':'},    COLONCOLON },
 767
 768 };
 769
 770 /* Some specific keywords */
 771
 772 struct keyword {
 773    char keyw[10];
 774    int token;
 775 };
 776
 777 static struct keyword keytab[] =
 778 {
 779     {"OR" ,   OROR       },
 780     {"IN",    IN         },/* Note space after IN */
 781     {"AND",   LOGICAL_AND},
 782     {"ABS",   ABS        },
 783     {"CHR",   CHR        },
 784     {"DEC",   DEC        },
 785     {"NOT",   NOT        },
 786     {"DIV",   DIV        },
 787     {"INC",   INC        },
 788     {"MAX",   MAX_FUNC   },
 789     {"MIN",   MIN_FUNC   },
 790     {"MOD",   MOD        },
 791     {"ODD",   ODD        },
 792     {"CAP",   CAP        },
 793     {"ORD",   ORD        },
 794     {"VAL",   VAL        },
 795     {"EXCL",  EXCL       },
 796     {"HIGH",  HIGH       },
 797     {"INCL",  INCL       },
 798     {"SIZE",  SIZE       },
 799     {"FLOAT", FLOAT_FUNC },
 800     {"TRUNC", TRUNC      },
 801     {"TSIZE", SIZE       },
 802 };
 803
 804
 805 /* Read one token, getting characters through lexptr.  */
 806
 807 /* This is where we will check to make sure that the language and the operators used are
 808    compatible  */
 809
 810 static int
 811 yylex ()
 812 {
 813   int c;
 814   int namelen;
 815   int i;
 816   char *tokstart;
 817   char quote;
 818
 819  retry:
 820
 821   prev_lexptr = lexptr;
 822
 823   tokstart = lexptr;
 824
 825
 826   /* See if it is a special token of length 2 */
 827   for( i = 0 ; i < (int) (sizeof tokentab2 / sizeof tokentab2[0]) ; i++)
 828      if (strncmp (tokentab2[i].name, tokstart, 2) == 0)
 829      {
 830         lexptr += 2;
 831         return tokentab2[i].token;
 832      }
 833
 834   switch (c = *tokstart)
 835     {
 836     case 0:
 837       return 0;
 838
 839     case ' ':
 840     case '\t':
 841     case '\n':
 842       lexptr++;
 843       goto retry;
 844
 845     case '(':
 846       paren_depth++;
 847       lexptr++;
 848       return c;
 849
 850     case ')':
 851       if (paren_depth == 0)
 852         return 0;
 853       paren_depth--;
 854       lexptr++;
 855       return c;
 856
 857     case ',':
 858       if (comma_terminates && paren_depth == 0)
 859         return 0;
 860       lexptr++;
 861       return c;
 862
 863     case '.':
 864       /* Might be a floating point number.  */
 865       if (lexptr[1] >= '0' && lexptr[1] <= '9')
 866         break;                  /* Falls into number code.  */
 867       else
 868       {
 869          lexptr++;
 870          return DOT;
 871       }
 872
 873 /* These are character tokens that appear as-is in the YACC grammar */
 874     case '+':
 875     case '-':
 876     case '*':
 877     case '/':
 878     case '^':
 879     case '<':
 880     case '>':
 881     case '[':
 882     case ']':
 883     case '=':
 884     case '{':
 885     case '}':
 886     case '#':
 887     case '@':
 888     case '~':
 889     case '&':
 890       lexptr++;
 891       return c;
 892
 893     case '\'' :
 894     case '"':
 895       quote = c;
 896       for (namelen = 1; (c = tokstart[namelen]) != quote && c != '\0'; namelen++)
 897         if (c == '\\')
 898           {
 899             c = tokstart[++namelen];
 900             if (c >= '0' && c <= '9')
 901               {
 902                 c = tokstart[++namelen];
 903                 if (c >= '0' && c <= '9')
 904                   c = tokstart[++namelen];
 905               }
 906           }
 907       if(c != quote)
 908          error("Unterminated string or character constant.");
 909       yylval.sval.ptr = tokstart + 1;
 910       yylval.sval.length = namelen - 1;
 911       lexptr += namelen + 1;
 912
 913       if(namelen == 2)          /* Single character */
 914       {
 915            yylval.ulval = tokstart[1];
 916            return CHAR;
 917       }
 918       else
 919          return STRING;
 920     }
 921
 922   /* Is it a number?  */
 923   /* Note:  We have already dealt with the case of the token '.'.
 924      See case '.' above.  */
 925   if ((c >= '0' && c <= '9'))
 926     {
 927       /* It's a number.  */
 928       int got_dot = 0, got_e = 0;
 929       char *p = tokstart;
 930       int toktype;
 931
 932       for (++p ;; ++p)
 933         {
 934           if (!got_e && (*p == 'e' || *p == 'E'))
 935             got_dot = got_e = 1;
 936           else if (!got_dot && *p == '.')
 937             got_dot = 1;
 938           else if (got_e && (p[-1] == 'e' || p[-1] == 'E')
 939                    && (*p == '-' || *p == '+'))
 940             /* This is the sign of the exponent, not the end of the
 941                number.  */
 942             continue;
 943           else if ((*p < '0' || *p > '9') &&
 944                    (*p < 'A' || *p > 'F') &&
 945                    (*p != 'H'))  /* Modula-2 hexadecimal number */
 946             break;
 947         }
 948         toktype = parse_number (p - tokstart);
 949         if (toktype == ERROR)
 950           {
 951             char *err_copy = (char *) alloca (p - tokstart + 1);
 952
 953             memcpy (err_copy, tokstart, p - tokstart);
 954             err_copy[p - tokstart] = 0;
 955             error ("Invalid number \"%s\".", err_copy);
 956           }
 957         lexptr = p;
 958         return toktype;
 959     }
 960
 961   if (!(c == '_' || c == '$'
 962         || (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z')))
 963     /* We must have come across a bad character (e.g. ';').  */
 964     error ("Invalid character '%c' in expression.", c);
 965
 966   /* It's a name.  See how long it is.  */
 967   namelen = 0;
 968   for (c = tokstart[namelen];
 969        (c == '_' || c == '$' || (c >= '0' && c <= '9')
 970         || (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z'));
 971        c = tokstart[++namelen])
 972     ;
 973
 974   /* The token "if" terminates the expression and is NOT
 975      removed from the input stream.  */
 976   if (namelen == 2 && tokstart[0] == 'i' && tokstart[1] == 'f')
 977     {
 978       return 0;
 979     }
 980
 981   lexptr += namelen;
 982
 983   /*  Lookup special keywords */
 984   for(i = 0 ; i < (int) (sizeof(keytab) / sizeof(keytab[0])) ; i++)
 985      if (namelen == strlen (keytab[i].keyw)
 986          && strncmp (tokstart, keytab[i].keyw, namelen) == 0)
 987            return keytab[i].token;
 988
 989   yylval.sval.ptr = tokstart;
 990   yylval.sval.length = namelen;
 991
 992   if (*tokstart == '$')
 993     {
 994       write_dollar_variable (yylval.sval);
 995       return INTERNAL_VAR;
 996     }
 997
 998   /* Use token-type BLOCKNAME for symbols that happen to be defined as
 999      functions.  If this is not so, then ...
1000      Use token-type TYPENAME for symbols that happen to be defined
1001      currently as names of types; NAME for other symbols.
1002      The caller is not constrained to care about the distinction.  */
1003  {
1004
1005
1006     char *tmp = copy_name (yylval.sval);
1007     struct symbol *sym;
1008
1009     if (lookup_symtab (tmp))
1010       return BLOCKNAME;
1011     sym = lookup_symbol (tmp, expression_context_block, VAR_DOMAIN, 0);
1012     if (sym && SYMBOL_CLASS (sym) == LOC_BLOCK)
1013       return BLOCKNAME;
1014     if (lookup_typename (parse_language, parse_gdbarch,
1015                          copy_name (yylval.sval), expression_context_block, 1))
1016       return TYPENAME;
1017
1018     if(sym)
1019     {
1020       switch(SYMBOL_CLASS (sym))
1021        {
1022        case LOC_STATIC:
1023        case LOC_REGISTER:
1024        case LOC_ARG:
1025        case LOC_REF_ARG:
1026        case LOC_REGPARM_ADDR:
1027        case LOC_LOCAL:
1028        case LOC_CONST:
1029        case LOC_CONST_BYTES:
1030        case LOC_OPTIMIZED_OUT:
1031        case LOC_COMPUTED:
1032           return NAME;
1033
1034        case LOC_TYPEDEF:
1035           return TYPENAME;
1036
1037        case LOC_BLOCK:
1038           return BLOCKNAME;
1039
1040        case LOC_UNDEF:
1041           error("internal:  Undefined class in m2lex()");
1042
1043        case LOC_LABEL:
1044        case LOC_UNRESOLVED:
1045           error("internal:  Unforseen case in m2lex()");
1046
1047        default:
1048           error ("unhandled token in m2lex()");
1049           break;
1050        }
1051     }
1052     else
1053     {
1054        /* Built-in BOOLEAN type.  This is sort of a hack. */
1055        if (strncmp (tokstart, "TRUE", 4) == 0)
1056        {
1057           yylval.ulval = 1;
1058           return M2_TRUE;
1059        }
1060        else if (strncmp (tokstart, "FALSE", 5) == 0)
1061        {
1062           yylval.ulval = 0;
1063           return M2_FALSE;
1064        }
1065     }
1066
1067     /* Must be another type of name... */
1068     return NAME;
1069  }
1070 }
1071
1072 #if 0           /* Unused */
1073 static char *
1074 make_qualname(mod,ident)
1075    char *mod, *ident;
1076 {
1077    char *new = malloc(strlen(mod)+strlen(ident)+2);
1078
1079    strcpy(new,mod);
1080    strcat(new,".");
1081    strcat(new,ident);
1082    return new;
1083 }
1084 #endif  /* 0 */
1085
1086 void
1087 yyerror (msg)
1088      char *msg;
1089 {
1090   if (prev_lexptr)
1091     lexptr = prev_lexptr;
1092
1093   error ("A %s in expression, near `%s'.", (msg ? msg : "error"), lexptr);
1094 }