gdb/ch-exp.y

   1 /* YACC grammar for Chill expressions, for GDB.
   2    Copyright (C) 1992 Free Software Foundation, Inc.
   3
   4 This file is part of GDB.
   5
   6 This program is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2 of the License, or
   9 (at your option) any later version.
  10
  11 This program is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with this program; if not, write to the Free Software
  18 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  19
  20 /* Parse a Chill expression from text in a string,
  21    and return the result as a  struct expression  pointer.
  22    That structure contains arithmetic operations in reverse polish,
  23    with constants represented by operations that are followed by special data.
  24    See expression.h for the details of the format.
  25    What is important here is that it can be built up sequentially
  26    during the process of parsing; the lower levels of the tree always
  27    come first in the result.
  28
  29    Note that malloc's and realloc's in this file are transformed to
  30    xmalloc and xrealloc respectively by the same sed command in the
  31    makefile that remaps any other malloc/realloc inserted by the parser
  32    generator.  Doing this with #defines and trying to control the interaction
  33    with include files (<malloc.h> and <stdlib.h> for example) just became
  34    too messy, particularly when such includes can be inserted at random
  35    times by the parser generator.
  36
  37    Also note that the language accepted by this parser is more liberal
  38    than the one accepted by an actual Chill compiler.  For example, the
  39    language rule that a simple name string can not be one of the reserved
  40    simple name strings is not enforced (e.g "case" is not treated as a
  41    reserved name).  Another example is that Chill is a strongly typed
  42    language, and certain expressions that violate the type constraints
  43    may still be evaluated if gdb can do so in a meaningful manner, while
  44    such expressions would be rejected by the compiler.  The reason for
  45    this more liberal behavior is the philosophy that the debugger
  46    is intended to be a tool that is used by the programmer when things
  47    go wrong, and as such, it should provide as few artificial barriers
  48    to it's use as possible.  If it can do something meaningful, even
  49    something that violates language contraints that are enforced by the
  50    compiler, it should do so without complaint.
  51
  52  */
  53
  54 %{
  55
  56 #include "defs.h"
  57 #include "expression.h"
  58 #include "language.h"
  59 #include "value.h"
  60 #include "parser-defs.h"
  61 #include "ch-lang.h"
  62
  63 /* Remap normal yacc parser interface names (yyparse, yylex, yyerror, etc),
  64    as well as gratuitiously global symbol names, so we can have multiple
  65    yacc generated parsers in gdb.  Note that these are only the variables
  66    produced by yacc.  If other parser generators (bison, byacc, etc) produce
  67    additional global names that conflict at link time, then those parser
  68    generators need to be fixed instead of adding those names to this list. */
  69
  70 #define yymaxdepth chill_maxdepth
  71 #define yyparse chill_parse
  72 #define yylex   chill_lex
  73 #define yyerror chill_error
  74 #define yylval  chill_lval
  75 #define yychar  chill_char
  76 #define yydebug chill_debug
  77 #define yypact  chill_pact
  78 #define yyr1    chill_r1
  79 #define yyr2    chill_r2
  80 #define yydef   chill_def
  81 #define yychk   chill_chk
  82 #define yypgo   chill_pgo
  83 #define yyact   chill_act
  84 #define yyexca  chill_exca
  85 #define yyerrflag chill_errflag
  86 #define yynerrs chill_nerrs
  87 #define yyps    chill_ps
  88 #define yypv    chill_pv
  89 #define yys     chill_s
  90 #define yy_yys  chill_yys
  91 #define yystate chill_state
  92 #define yytmp   chill_tmp
  93 #define yyv     chill_v
  94 #define yy_yyv  chill_yyv
  95 #define yyval   chill_val
  96 #define yylloc  chill_lloc
  97 #define yyreds  chill_reds              /* With YYDEBUG defined */
  98 #define yytoks  chill_toks              /* With YYDEBUG defined */
  99
 100 #ifndef YYDEBUG
 101 #define YYDEBUG 0               /* Default to no yydebug support */
 102 #endif
 103
 104 int
 105 yyparse PARAMS ((void));
 106
 107 static int
 108 yylex PARAMS ((void));
 109
 110 void
 111 yyerror PARAMS ((char *));
 112
 113 %}
 114
 115 /* Although the yacc "value" of an expression is not used,
 116    since the result is stored in the structure being created,
 117    other node types do have values.  */
 118
 119 %union
 120   {
 121     LONGEST lval;
 122     unsigned LONGEST ulval;
 123     struct {
 124       LONGEST val;
 125       struct type *type;
 126     } typed_val;
 127     double dval;
 128     struct symbol *sym;
 129     struct type *tval;
 130     struct stoken sval;
 131     struct ttype tsym;
 132     struct symtoken ssym;
 133     int voidval;
 134     struct block *bval;
 135     enum exp_opcode opcode;
 136     struct internalvar *ivar;
 137
 138     struct type **tvec;
 139     int *ivec;
 140   }
 141
 142 %token <voidval> FIXME_01
 143 %token <voidval> FIXME_02
 144 %token <voidval> FIXME_03
 145 %token <voidval> FIXME_04
 146 %token <voidval> FIXME_05
 147 %token <voidval> FIXME_06
 148 %token <voidval> FIXME_07
 149 %token <voidval> FIXME_08
 150 %token <voidval> FIXME_09
 151 %token <voidval> FIXME_10
 152 %token <voidval> FIXME_11
 153 %token <voidval> FIXME_12
 154 %token <voidval> FIXME_13
 155 %token <voidval> FIXME_14
 156 %token <voidval> FIXME_15
 157 %token <voidval> FIXME_16
 158 %token <voidval> FIXME_17
 159 %token <voidval> FIXME_18
 160 %token <voidval> FIXME_19
 161 %token <voidval> FIXME_20
 162 %token <voidval> FIXME_21
 163 %token <voidval> FIXME_22
 164 %token <voidval> FIXME_23
 165 %token <voidval> FIXME_24
 166 %token <voidval> FIXME_25
 167 %token <voidval> FIXME_26
 168 %token <voidval> FIXME_27
 169 %token <voidval> FIXME_28
 170 %token <voidval> FIXME_29
 171 %token <voidval> FIXME_30
 172
 173 %token <typed_val>      INTEGER_LITERAL
 174 %token <ulval>          BOOLEAN_LITERAL
 175 %token <typed_val>      CHARACTER_LITERAL
 176 %token <dval>           FLOAT_LITERAL
 177 %token <ssym>           GENERAL_PROCEDURE_NAME
 178 %token <ssym>           LOCATION_NAME
 179 %token <voidval>        SET_LITERAL
 180 %token <voidval>        EMPTINESS_LITERAL
 181 %token <sval>           CHARACTER_STRING_LITERAL
 182 %token <sval>           BIT_STRING_LITERAL
 183
 184 %token <voidval>        '.'
 185 %token <voidval>        ';'
 186 %token <voidval>        ':'
 187 %token <voidval>        CASE
 188 %token <voidval>        OF
 189 %token <voidval>        ESAC
 190 %token <voidval>        LOGIOR
 191 %token <voidval>        ORIF
 192 %token <voidval>        LOGXOR
 193 %token <voidval>        LOGAND
 194 %token <voidval>        ANDIF
 195 %token <voidval>        '='
 196 %token <voidval>        NOTEQUAL
 197 %token <voidval>        '>'
 198 %token <voidval>        GTR
 199 %token <voidval>        '<'
 200 %token <voidval>        LEQ
 201 %token <voidval>        IN
 202 %token <voidval>        '+'
 203 %token <voidval>        '-'
 204 %token <voidval>        '*'
 205 %token <voidval>        '/'
 206 %token <voidval>        SLASH_SLASH
 207 %token <voidval>        MOD
 208 %token <voidval>        REM
 209 %token <voidval>        NOT
 210 %token <voidval>        POINTER
 211 %token <voidval>        RECEIVE
 212 %token <voidval>        '['
 213 %token <voidval>        ']'
 214 %token <voidval>        '('
 215 %token <voidval>        ')'
 216 %token <voidval>        UP
 217 %token <voidval>        IF
 218 %token <voidval>        THEN
 219 %token <voidval>        ELSE
 220 %token <voidval>        FI
 221 %token <voidval>        ELSIF
 222 %token <voidval>        ILLEGAL_TOKEN
 223 %token <voidval>        NUM
 224 %token <voidval>        PRED
 225 %token <voidval>        SUCC
 226 %token <voidval>        ABS
 227 %token <voidval>        CARD
 228 %token <voidval>        MAX
 229 %token <voidval>        MIN
 230 %token <voidval>        SIZE
 231 %token <voidval>        UPPER
 232 %token <voidval>        LOWER
 233 %token <voidval>        LENGTH
 234
 235 /* Tokens which are not Chill tokens used in expressions, but rather GDB
 236    specific things that we recognize in the same context as Chill tokens
 237    (register names for example). */
 238
 239 %token <lval>           GDB_REGNAME     /* Machine register name */
 240 %token <lval>           GDB_LAST        /* Value history */
 241 %token <ivar>           GDB_VARIABLE    /* Convenience variable */
 242 %token <voidval>        GDB_ASSIGNMENT  /* Assign value to somewhere */
 243
 244 %type <voidval>         location
 245 %type <voidval>         access_name
 246 %type <voidval>         primitive_value
 247 %type <voidval>         location_contents
 248 %type <voidval>         value_name
 249 %type <voidval>         literal
 250 %type <voidval>         tuple
 251 %type <voidval>         value_string_element
 252 %type <voidval>         value_string_slice
 253 %type <voidval>         value_array_element
 254 %type <voidval>         value_array_slice
 255 %type <voidval>         value_structure_field
 256 %type <voidval>         expression_conversion
 257 %type <voidval>         value_procedure_call
 258 %type <voidval>         value_built_in_routine_call
 259 %type <voidval>         chill_value_built_in_routine_call
 260 %type <voidval>         start_expression
 261 %type <voidval>         zero_adic_operator
 262 %type <voidval>         parenthesised_expression
 263 %type <voidval>         value
 264 %type <voidval>         undefined_value
 265 %type <voidval>         expression
 266 %type <voidval>         conditional_expression
 267 %type <voidval>         then_alternative
 268 %type <voidval>         else_alternative
 269 %type <voidval>         sub_expression
 270 %type <voidval>         value_case_alternative
 271 %type <voidval>         operand_0
 272 %type <voidval>         operand_1
 273 %type <voidval>         operand_2
 274 %type <voidval>         operand_3
 275 %type <voidval>         operand_4
 276 %type <voidval>         operand_5
 277 %type <voidval>         operand_6
 278 %type <voidval>         synonym_name
 279 %type <voidval>         value_enumeration_name
 280 %type <voidval>         value_do_with_name
 281 %type <voidval>         value_receive_name
 282 %type <voidval>         string_primitive_value
 283 %type <voidval>         start_element
 284 %type <voidval>         left_element
 285 %type <voidval>         right_element
 286 %type <voidval>         slice_size
 287 %type <voidval>         array_primitive_value
 288 %type <voidval>         expression_list
 289 %type <voidval>         lower_element
 290 %type <voidval>         upper_element
 291 %type <voidval>         first_element
 292 %type <voidval>         structure_primitive_value
 293 %type <voidval>         field_name
 294 %type <voidval>         mode_argument
 295 %type <voidval>         upper_lower_argument
 296 %type <voidval>         length_argument
 297 %type <voidval>         mode_name
 298 %type <voidval>         array_mode_name
 299 %type <voidval>         string_mode_name
 300 %type <voidval>         variant_structure_mode_name
 301 %type <voidval>         boolean_expression
 302 %type <voidval>         case_selector_list
 303 %type <voidval>         subexpression
 304 %type <voidval>         case_label_specification
 305 %type <voidval>         buffer_location
 306
 307 %type <voidval>         single_assignment_action
 308
 309 %%
 310
 311 /* Z.200, 5.3.1 */
 312
 313 value           :       expression
 314                         {
 315                           $$ = 0;       /* FIXME */
 316                         }
 317                 |       undefined_value
 318                         {
 319                           $$ = 0;       /* FIXME */
 320                         }
 321                 ;
 322
 323 undefined_value :       FIXME_01
 324                         {
 325                           $$ = 0;       /* FIXME */
 326                         }
 327                 ;
 328
 329 /* Z.200, 4.2.1 */
 330
 331 location        :       access_name
 332                         {
 333                           $$ = 0;       /* FIXME */
 334                         }
 335                 |       FIXME_02
 336                         {
 337                           $$ = 0;       /* FIXME */
 338                         }
 339                 ;
 340
 341 /* Z.200, 4.2.2 */
 342
 343 access_name     :       LOCATION_NAME
 344                         {
 345                           write_exp_elt_opcode (OP_VAR_VALUE);
 346                           write_exp_elt_sym ($1.sym);
 347                           write_exp_elt_opcode (OP_VAR_VALUE);
 348                         }
 349                 |       GDB_LAST                /* gdb specific */
 350                         {
 351                           write_exp_elt_opcode (OP_LAST);
 352                           write_exp_elt_longcst ($1);
 353                           write_exp_elt_opcode (OP_LAST);
 354                         }
 355                 |       GDB_REGNAME             /* gdb specific */
 356                         {
 357                           write_exp_elt_opcode (OP_REGISTER);
 358                           write_exp_elt_longcst ($1);
 359                           write_exp_elt_opcode (OP_REGISTER);
 360                         }
 361                 |       GDB_VARIABLE    /* gdb specific */
 362                         {
 363                           write_exp_elt_opcode (OP_INTERNALVAR);
 364                           write_exp_elt_intern ($1);
 365                           write_exp_elt_opcode (OP_INTERNALVAR);
 366                         }
 367                 |       FIXME_03
 368                         {
 369                           $$ = 0;       /* FIXME */
 370                         }
 371                 ;
 372
 373 /* Z.200, 4.2.8 */
 374
 375 expression_list :       expression
 376                         {
 377                           arglist_len = 1;
 378                         }
 379                 |       expression_list ',' expression
 380                         {
 381                           arglist_len++;
 382                         }
 383
 384 /* Z.200, 5.2.1 */
 385
 386 primitive_value :       location_contents
 387                         {
 388                           $$ = 0;       /* FIXME */
 389                         }
 390                 |       value_name
 391                         {
 392                           $$ = 0;       /* FIXME */
 393                         }
 394                 |       literal
 395                         {
 396                           $$ = 0;       /* FIXME */
 397                         }
 398                 |       tuple
 399                         {
 400                           $$ = 0;       /* FIXME */
 401                         }
 402                 |       value_string_element
 403                         {
 404                           $$ = 0;       /* FIXME */
 405                         }
 406                 |       value_string_slice
 407                         {
 408                           $$ = 0;       /* FIXME */
 409                         }
 410                 |       value_array_element
 411                         {
 412                           $$ = 0;       /* FIXME */
 413                         }
 414                 |       value_array_slice
 415                         {
 416                           $$ = 0;       /* FIXME */
 417                         }
 418                 |       value_structure_field
 419                         {
 420                           $$ = 0;       /* FIXME */
 421                         }
 422                 |       expression_conversion
 423                         {
 424                           $$ = 0;       /* FIXME */
 425                         }
 426                 |       value_procedure_call
 427                         {
 428                           $$ = 0;       /* FIXME */
 429                         }
 430                 |       value_built_in_routine_call
 431                         {
 432                           $$ = 0;       /* FIXME */
 433                         }
 434                 |       start_expression
 435                         {
 436                           $$ = 0;       /* FIXME */
 437                         }
 438                 |       zero_adic_operator
 439                         {
 440                           $$ = 0;       /* FIXME */
 441                         }
 442                 |       parenthesised_expression
 443                         {
 444                           $$ = 0;       /* FIXME */
 445                         }
 446                 ;
 447
 448 /* Z.200, 5.2.2 */
 449
 450 location_contents:      location
 451                         {
 452                           $$ = 0;       /* FIXME */
 453                         }
 454                 ;
 455
 456 /* Z.200, 5.2.3 */
 457
 458 value_name      :       synonym_name
 459                         {
 460                           $$ = 0;       /* FIXME */
 461                         }
 462                 |       value_enumeration_name
 463                         {
 464                           $$ = 0;       /* FIXME */
 465                         }
 466                 |       value_do_with_name
 467                         {
 468                           $$ = 0;       /* FIXME */
 469                         }
 470                 |       value_receive_name
 471                         {
 472                           $$ = 0;       /* FIXME */
 473                         }
 474                 |       GENERAL_PROCEDURE_NAME
 475                         {
 476                           write_exp_elt_opcode (OP_VAR_VALUE);
 477                           write_exp_elt_sym ($1.sym);
 478                           write_exp_elt_opcode (OP_VAR_VALUE);
 479                         }
 480                 ;
 481
 482 /* Z.200, 5.2.4.1 */
 483
 484 literal         :       INTEGER_LITERAL
 485                         {
 486                           write_exp_elt_opcode (OP_LONG);
 487                           write_exp_elt_type ($1.type);
 488                           write_exp_elt_longcst ((LONGEST) ($1.val));
 489                           write_exp_elt_opcode (OP_LONG);
 490                         }
 491                 |       BOOLEAN_LITERAL
 492                         {
 493                           write_exp_elt_opcode (OP_BOOL);
 494                           write_exp_elt_longcst ((LONGEST) $1);
 495                           write_exp_elt_opcode (OP_BOOL);
 496                         }
 497                 |       CHARACTER_LITERAL
 498                         {
 499                           write_exp_elt_opcode (OP_LONG);
 500                           write_exp_elt_type ($1.type);
 501                           write_exp_elt_longcst ((LONGEST) ($1.val));
 502                           write_exp_elt_opcode (OP_LONG);
 503                         }
 504                 |       FLOAT_LITERAL
 505                         {
 506                           write_exp_elt_opcode (OP_DOUBLE);
 507                           write_exp_elt_type (builtin_type_double);
 508                           write_exp_elt_dblcst ($1);
 509                           write_exp_elt_opcode (OP_DOUBLE);
 510                         }
 511                 |       SET_LITERAL
 512                         {
 513                           $$ = 0;       /* FIXME */
 514                         }
 515                 |       EMPTINESS_LITERAL
 516                         {
 517                           $$ = 0;       /* FIXME */
 518                         }
 519                 |       CHARACTER_STRING_LITERAL
 520                         {
 521                           write_exp_elt_opcode (OP_STRING);
 522                           write_exp_string ($1);
 523                           write_exp_elt_opcode (OP_STRING);
 524                         }
 525                 |       BIT_STRING_LITERAL
 526                         {
 527                           write_exp_elt_opcode (OP_BITSTRING);
 528                           write_exp_bitstring ($1);
 529                           write_exp_elt_opcode (OP_BITSTRING);
 530                         }
 531                 ;
 532
 533 /* Z.200, 5.2.5 */
 534
 535 tuple           :       FIXME_04
 536                         {
 537                           $$ = 0;       /* FIXME */
 538                         }
 539                 ;
 540
 541
 542 /* Z.200, 5.2.6 */
 543
 544 value_string_element:   string_primitive_value '(' start_element ')'
 545                         {
 546                           $$ = 0;       /* FIXME */
 547                         }
 548                 ;
 549
 550 /* Z.200, 5.2.7 */
 551
 552 value_string_slice:     string_primitive_value '(' left_element ':' right_element ')'
 553                         {
 554                           $$ = 0;       /* FIXME */
 555                         }
 556                 |       string_primitive_value '(' start_element UP slice_size ')'
 557                         {
 558                           $$ = 0;       /* FIXME */
 559                         }
 560                 ;
 561
 562 /* Z.200, 5.2.8 */
 563
 564 value_array_element:    array_primitive_value '('
 565                                 /* This is to save the value of arglist_len
 566                                    being accumulated for each dimension. */
 567                                 { start_arglist (); }
 568                         expression_list ')'
 569                         {
 570                           write_exp_elt_opcode (MULTI_SUBSCRIPT);
 571                           write_exp_elt_longcst ((LONGEST) end_arglist ());
 572                           write_exp_elt_opcode (MULTI_SUBSCRIPT);
 573                         }
 574                 ;
 575
 576 /* Z.200, 5.2.9 */
 577
 578 value_array_slice:      array_primitive_value '(' lower_element ':' upper_element ')'
 579                         {
 580                           $$ = 0;       /* FIXME */
 581                         }
 582                 |       array_primitive_value '(' first_element UP slice_size ')'
 583                         {
 584                           $$ = 0;       /* FIXME */
 585                         }
 586                 ;
 587
 588 /* Z.200, 5.2.10 */
 589
 590 value_structure_field:  structure_primitive_value '.' field_name
 591                         {
 592                           $$ = 0;       /* FIXME */
 593                         }
 594                 ;
 595
 596 /* Z.200, 5.2.11 */
 597
 598 expression_conversion:  mode_name parenthesised_expression
 599                         {
 600                           $$ = 0;       /* FIXME */
 601                         }
 602                 ;
 603
 604 /* Z.200, 5.2.12 */
 605
 606 value_procedure_call:   FIXME_05
 607                         {
 608                           $$ = 0;       /* FIXME */
 609                         }
 610                 ;
 611
 612 /* Z.200, 5.2.13 */
 613
 614 value_built_in_routine_call:    chill_value_built_in_routine_call
 615                         {
 616                           $$ = 0;       /* FIXME */
 617                         }
 618                 ;
 619
 620 /* Z.200, 5.2.14 */
 621
 622 start_expression:       FIXME_06
 623                         {
 624                           $$ = 0;       /* FIXME */
 625                         }       /* Not in GNU-Chill */
 626                 ;
 627
 628 /* Z.200, 5.2.15 */
 629
 630 zero_adic_operator:     FIXME_07
 631                         {
 632                           $$ = 0;       /* FIXME */
 633                         }
 634                 ;
 635
 636 /* Z.200, 5.2.16 */
 637
 638 parenthesised_expression:       '(' expression ')'
 639                         {
 640                           $$ = 0;       /* FIXME */
 641                         }
 642                 ;
 643
 644 /* Z.200, 5.3.2 */
 645
 646 expression      :       operand_0
 647                         {
 648                           $$ = 0;       /* FIXME */
 649                         }
 650                 |       conditional_expression
 651                         {
 652                           $$ = 0;       /* FIXME */
 653                         }
 654                 ;
 655
 656 conditional_expression : IF boolean_expression then_alternative else_alternative FI
 657                         {
 658                           $$ = 0;       /* FIXME */
 659                         }
 660                 |       CASE case_selector_list OF value_case_alternative '[' ELSE sub_expression ']' ESAC
 661                         {
 662                           $$ = 0;       /* FIXME */
 663                         }
 664                 ;
 665
 666 then_alternative:       THEN subexpression
 667                         {
 668                           $$ = 0;       /* FIXME */
 669                         }
 670                 ;
 671
 672 else_alternative:       ELSE subexpression
 673                         {
 674                           $$ = 0;       /* FIXME */
 675                         }
 676                 |       ELSIF boolean_expression then_alternative else_alternative
 677                         {
 678                           $$ = 0;       /* FIXME */
 679                         }
 680                 ;
 681
 682 sub_expression  :       expression
 683                         {
 684                           $$ = 0;       /* FIXME */
 685                         }
 686                 ;
 687
 688 value_case_alternative: case_label_specification ':' sub_expression ';'
 689                         {
 690                           $$ = 0;       /* FIXME */
 691                         }
 692                 ;
 693
 694 /* Z.200, 5.3.3 */
 695
 696 operand_0       :       operand_1
 697                         {
 698                           $$ = 0;       /* FIXME */
 699                         }
 700                 |       operand_0 LOGIOR operand_1
 701                         {
 702                           write_exp_elt_opcode (BINOP_BITWISE_IOR);
 703                         }
 704                 |       operand_0 ORIF operand_1
 705                         {
 706                           $$ = 0;       /* FIXME */
 707                         }
 708                 |       operand_0 LOGXOR operand_1
 709                         {
 710                           write_exp_elt_opcode (BINOP_BITWISE_XOR);
 711                         }
 712                 |       single_assignment_action
 713                         {
 714                           $$ = 0;       /* FIXME */
 715                         }
 716                 ;
 717
 718 /* Z.200, 5.3.4 */
 719
 720 operand_1       :       operand_2
 721                         {
 722                           $$ = 0;       /* FIXME */
 723                         }
 724                 |       operand_1 LOGAND operand_2
 725                         {
 726                           write_exp_elt_opcode (BINOP_BITWISE_AND);
 727                         }
 728                 |       operand_1 ANDIF operand_2
 729                         {
 730                           $$ = 0;       /* FIXME */
 731                         }
 732                 ;
 733
 734 /* Z.200, 5.3.5 */
 735
 736 operand_2       :       operand_3
 737                         {
 738                           $$ = 0;       /* FIXME */
 739                         }
 740                 |       operand_2 '=' operand_3
 741                         {
 742                           write_exp_elt_opcode (BINOP_EQUAL);
 743                         }
 744                 |       operand_2 NOTEQUAL operand_3
 745                         {
 746                           write_exp_elt_opcode (BINOP_NOTEQUAL);
 747                         }
 748                 |       operand_2 '>' operand_3
 749                         {
 750                           write_exp_elt_opcode (BINOP_GTR);
 751                         }
 752                 |       operand_2 GTR operand_3
 753                         {
 754                           write_exp_elt_opcode (BINOP_GEQ);
 755                         }
 756                 |       operand_2 '<' operand_3
 757                         {
 758                           write_exp_elt_opcode (BINOP_LESS);
 759                         }
 760                 |       operand_2 LEQ operand_3
 761                         {
 762                           write_exp_elt_opcode (BINOP_LEQ);
 763                         }
 764                 |       operand_2 IN operand_3
 765                         {
 766                           $$ = 0;       /* FIXME */
 767                         }
 768                 ;
 769
 770
 771 /* Z.200, 5.3.6 */
 772
 773 operand_3       :       operand_4
 774                         {
 775                           $$ = 0;       /* FIXME */
 776                         }
 777                 |       operand_3 '+' operand_4
 778                         {
 779                           write_exp_elt_opcode (BINOP_ADD);
 780                         }
 781                 |       operand_3 '-' operand_4
 782                         {
 783                           write_exp_elt_opcode (BINOP_SUB);
 784                         }
 785                 |       operand_3 SLASH_SLASH operand_4
 786                         {
 787                           write_exp_elt_opcode (BINOP_CONCAT);
 788                         }
 789                 ;
 790
 791 /* Z.200, 5.3.7 */
 792
 793 operand_4       :       operand_5
 794                         {
 795                           $$ = 0;       /* FIXME */
 796                         }
 797                 |       operand_4 '*' operand_5
 798                         {
 799                           write_exp_elt_opcode (BINOP_MUL);
 800                         }
 801                 |       operand_4 '/' operand_5
 802                         {
 803                           write_exp_elt_opcode (BINOP_DIV);
 804                         }
 805                 |       operand_4 MOD operand_5
 806                         {
 807                           write_exp_elt_opcode (BINOP_MOD);
 808                         }
 809                 |       operand_4 REM operand_5
 810                         {
 811                           write_exp_elt_opcode (BINOP_REM);
 812                         }
 813                 ;
 814
 815 /* Z.200, 5.3.8 */
 816 /* Note that we accept any expression for BINOP_CONCAT, not just
 817    integer literal expressions. (FIXME?) */
 818
 819 operand_5       :       operand_6
 820                         {
 821                           $$ = 0;       /* FIXME */
 822                         }
 823                 |       '-' operand_6
 824                         {
 825                           write_exp_elt_opcode (UNOP_NEG);
 826                         }
 827                 |       NOT operand_6
 828                         {
 829                           write_exp_elt_opcode (UNOP_LOGICAL_NOT);
 830                         }
 831                 |       parenthesised_expression operand_6
 832                         {
 833                           write_exp_elt_opcode (BINOP_CONCAT);
 834                         }
 835                 ;
 836
 837 /* Z.200, 5.3.9 */
 838
 839 operand_6       :       POINTER location
 840                         {
 841                           $$ = 0;       /* FIXME */
 842                         }
 843                 |       RECEIVE buffer_location
 844                         {
 845                           $$ = 0;       /* FIXME */
 846                         }
 847                 |       primitive_value
 848                         {
 849                           $$ = 0;       /* FIXME */
 850                         }
 851                 ;
 852
 853
 854 /* Z.200, 6.2 */
 855
 856 single_assignment_action :
 857                         location GDB_ASSIGNMENT value
 858                         {
 859                           write_exp_elt_opcode (BINOP_ASSIGN);
 860                         }
 861                 ;
 862
 863 /* Z.200, 6.20.3 */
 864
 865 chill_value_built_in_routine_call :
 866                         NUM '(' expression ')'
 867                         {
 868                           $$ = 0;       /* FIXME */
 869                         }
 870                 |       PRED '(' expression ')'
 871                         {
 872                           $$ = 0;       /* FIXME */
 873                         }
 874                 |       SUCC '(' expression ')'
 875                         {
 876                           $$ = 0;       /* FIXME */
 877                         }
 878                 |       ABS '(' expression ')'
 879                         {
 880                           $$ = 0;       /* FIXME */
 881                         }
 882                 |       CARD '(' expression ')'
 883                         {
 884                           $$ = 0;       /* FIXME */
 885                         }
 886                 |       MAX '(' expression ')'
 887                         {
 888                           $$ = 0;       /* FIXME */
 889                         }
 890                 |       MIN '(' expression ')'
 891                         {
 892                           $$ = 0;       /* FIXME */
 893                         }
 894                 |       SIZE '(' location ')'
 895                         {
 896                           $$ = 0;       /* FIXME */
 897                         }
 898                 |       SIZE '(' mode_argument ')'
 899                         {
 900                           $$ = 0;       /* FIXME */
 901                         }
 902                 |       UPPER '(' upper_lower_argument ')'
 903                         {
 904                           $$ = 0;       /* FIXME */
 905                         }
 906                 |       LOWER '(' upper_lower_argument ')'
 907                         {
 908                           $$ = 0;       /* FIXME */
 909                         }
 910                 |       LENGTH '(' length_argument ')'
 911                         {
 912                           $$ = 0;       /* FIXME */
 913                         }
 914                 ;
 915
 916 mode_argument :         mode_name
 917                         {
 918                           $$ = 0;       /* FIXME */
 919                         }
 920                 |       array_mode_name '(' expression ')'
 921                         {
 922                           $$ = 0;       /* FIXME */
 923                         }
 924                 |       string_mode_name '(' expression ')'
 925                         {
 926                           $$ = 0;       /* FIXME */
 927                         }
 928                 |       variant_structure_mode_name '(' expression_list ')'
 929                         {
 930                           $$ = 0;       /* FIXME */
 931                         }
 932                 ;
 933
 934 upper_lower_argument :  location
 935                         {
 936                           $$ = 0;       /* FIXME */
 937                         }
 938                 |       expression
 939                         {
 940                           $$ = 0;       /* FIXME */
 941                         }
 942                 |       mode_name
 943                         {
 944                           $$ = 0;       /* FIXME */
 945                         }
 946                 ;
 947
 948 length_argument :       location
 949                         {
 950                           $$ = 0;       /* FIXME */
 951                         }
 952                 |       expression
 953                         {
 954                           $$ = 0;       /* FIXME */
 955                         }
 956                 ;
 957
 958 /* Z.200, 12.4.3 */
 959
 960 array_primitive_value : primitive_value
 961                         {
 962                           $$ = 0;
 963                         }
 964                 ;
 965
 966
 967 /* Things which still need productions... */
 968
 969 array_mode_name         :       FIXME_08 { $$ = 0; }
 970 string_mode_name        :       FIXME_09 { $$ = 0; }
 971 variant_structure_mode_name:    FIXME_10 { $$ = 0; }
 972 synonym_name            :       FIXME_11 { $$ = 0; }
 973 value_enumeration_name  :       FIXME_12 { $$ = 0; }
 974 value_do_with_name      :       FIXME_13 { $$ = 0; }
 975 value_receive_name      :       FIXME_14 { $$ = 0; }
 976 string_primitive_value  :       FIXME_15 { $$ = 0; }
 977 start_element           :       FIXME_16 { $$ = 0; }
 978 left_element            :       FIXME_17 { $$ = 0; }
 979 right_element           :       FIXME_18 { $$ = 0; }
 980 slice_size              :       FIXME_19 { $$ = 0; }
 981 lower_element           :       FIXME_20 { $$ = 0; }
 982 upper_element           :       FIXME_21 { $$ = 0; }
 983 first_element           :       FIXME_22 { $$ = 0; }
 984 structure_primitive_value:      FIXME_23 { $$ = 0; }
 985 field_name              :       FIXME_24 { $$ = 0; }
 986 mode_name               :       FIXME_25 { $$ = 0; }
 987 boolean_expression      :       FIXME_26 { $$ = 0; }
 988 case_selector_list      :       FIXME_27 { $$ = 0; }
 989 subexpression           :       FIXME_28 { $$ = 0; }
 990 case_label_specification:       FIXME_29 { $$ = 0; }
 991 buffer_location         :       FIXME_30 { $$ = 0; }
 992
 993 %%
 994
 995 /* Implementation of a dynamically expandable buffer for processing input
 996    characters acquired through lexptr and building a value to return in
 997    yylval. */
 998
 999 static char *tempbuf;           /* Current buffer contents */
1000 static int tempbufsize;         /* Size of allocated buffer */
1001 static int tempbufindex;        /* Current index into buffer */
1002
1003 #define GROWBY_MIN_SIZE 64      /* Minimum amount to grow buffer by */
1004
1005 #define CHECKBUF(size) \
1006   do { \
1007     if (tempbufindex + (size) >= tempbufsize) \
1008       { \
1009         growbuf_by_size (size); \
1010       } \
1011   } while (0);
1012
1013 /* Grow the static temp buffer if necessary, including allocating the first one
1014    on demand. */
1015
1016 static void
1017 growbuf_by_size (count)
1018      int count;
1019 {
1020   int growby;
1021
1022   growby = max (count, GROWBY_MIN_SIZE);
1023   tempbufsize += growby;
1024   if (tempbuf == NULL)
1025     {
1026       tempbuf = (char *) malloc (tempbufsize);
1027     }
1028   else
1029     {
1030       tempbuf = (char *) realloc (tempbuf, tempbufsize);
1031     }
1032 }
1033
1034 /* Try to consume a simple name string token.  If successful, returns
1035    a pointer to a nullbyte terminated copy of the name that can be used
1036    in symbol table lookups.  If not successful, returns NULL. */
1037
1038 static char *
1039 match_simple_name_string ()
1040 {
1041   char *tokptr = lexptr;
1042
1043   if (isalpha (*tokptr))
1044     {
1045       do {
1046         tokptr++;
1047       } while (isalpha (*tokptr) || isdigit (*tokptr) || (*tokptr == '_'));
1048       yylval.sval.ptr = lexptr;
1049       yylval.sval.length = tokptr - lexptr;
1050       lexptr = tokptr;
1051       return (copy_name (yylval.sval));
1052     }
1053   return (NULL);
1054 }
1055
1056 /* Start looking for a value composed of valid digits as set by the base
1057    in use.  Note that '_' characters are valid anywhere, in any quantity,
1058    and are simply ignored.  Since we must find at least one valid digit,
1059    or reject this token as an integer literal, we keep track of how many
1060    digits we have encountered. */
1061
1062 static int
1063 decode_integer_value (base, tokptrptr, ivalptr)
1064   int base;
1065   char **tokptrptr;
1066   int *ivalptr;
1067 {
1068   char *tokptr = *tokptrptr;
1069   int temp;
1070   int digits = 0;
1071
1072   while (*tokptr != '\0')
1073     {
1074       temp = tolower (*tokptr);
1075       tokptr++;
1076       switch (temp)
1077         {
1078         case '_':
1079           continue;
1080         case '0':  case '1':  case '2':  case '3':  case '4':
1081         case '5':  case '6':  case '7':  case '8':  case '9':
1082           temp -= '0';
1083           break;
1084         case 'a':  case 'b':  case 'c':  case 'd':  case 'e': case 'f':
1085           temp -= 'a';
1086           temp += 10;
1087           break;
1088         default:
1089           temp = base;
1090           break;
1091         }
1092       if (temp < base)
1093         {
1094           digits++;
1095           *ivalptr *= base;
1096           *ivalptr += temp;
1097         }
1098       else
1099         {
1100           /* Found something not in domain for current base. */
1101           tokptr--;     /* Unconsume what gave us indigestion. */
1102           break;
1103         }
1104     }
1105
1106   /* If we didn't find any digits, then we don't have a valid integer
1107      value, so reject the entire token.  Otherwise, update the lexical
1108      scan pointer, and return non-zero for success. */
1109
1110   if (digits == 0)
1111     {
1112       return (0);
1113     }
1114   else
1115     {
1116       *tokptrptr = tokptr;
1117       return (1);
1118     }
1119 }
1120
1121 static int
1122 decode_integer_literal (valptr, tokptrptr)
1123   int *valptr;
1124   char **tokptrptr;
1125 {
1126   char *tokptr = *tokptrptr;
1127   int base = 0;
1128   int ival = 0;
1129   int explicit_base = 0;
1130
1131   /* Look for an explicit base specifier, which is optional. */
1132
1133   switch (*tokptr)
1134     {
1135     case 'd':
1136     case 'D':
1137       explicit_base++;
1138       base = 10;
1139       tokptr++;
1140       break;
1141     case 'b':
1142     case 'B':
1143       explicit_base++;
1144       base = 2;
1145       tokptr++;
1146       break;
1147     case 'h':
1148     case 'H':
1149       explicit_base++;
1150       base = 16;
1151       tokptr++;
1152       break;
1153     case 'o':
1154     case 'O':
1155       explicit_base++;
1156       base = 8;
1157       tokptr++;
1158       break;
1159     default:
1160       base = 10;
1161       break;
1162     }
1163
1164   /* If we found an explicit base ensure that the character after the
1165      explicit base is a single quote. */
1166
1167   if (explicit_base && (*tokptr++ != '\''))
1168     {
1169       return (0);
1170     }
1171
1172   /* Attempt to decode whatever follows as an integer value in the
1173      indicated base, updating the token pointer in the process and
1174      computing the value into ival.  Also, if we have an explicit
1175      base, then the next character must not be a single quote, or we
1176      have a bitstring literal, so reject the entire token in this case.
1177      Otherwise, update the lexical scan pointer, and return non-zero
1178      for success. */
1179
1180   if (!decode_integer_value (base, &tokptr, &ival))
1181     {
1182       return (0);
1183     }
1184   else if (explicit_base && (*tokptr == '\''))
1185     {
1186       return (0);
1187     }
1188   else
1189     {
1190       *valptr = ival;
1191       *tokptrptr = tokptr;
1192       return (1);
1193     }
1194 }
1195
1196 /*  If it wasn't for the fact that floating point values can contain '_'
1197     characters, we could just let strtod do all the hard work by letting it
1198     try to consume as much of the current token buffer as possible and
1199     find a legal conversion.  Unfortunately we need to filter out the '_'
1200     characters before calling strtod, which we do by copying the other
1201     legal chars to a local buffer to be converted.  However since we also
1202     need to keep track of where the last unconsumed character in the input
1203     buffer is, we have transfer only as many characters as may compose a
1204     legal floating point value. */
1205
1206 static int
1207 match_float_literal ()
1208 {
1209   char *tokptr = lexptr;
1210   char *buf;
1211   char *copy;
1212   char ch;
1213   double dval;
1214   extern double strtod ();
1215
1216   /* Make local buffer in which to build the string to convert.  This is
1217      required because underscores are valid in chill floating point numbers
1218      but not in the string passed to strtod to convert.  The string will be
1219      no longer than our input string. */
1220
1221   copy = buf = (char *) alloca (strlen (tokptr) + 1);
1222
1223   /* Transfer all leading digits to the conversion buffer, discarding any
1224      underscores. */
1225
1226   while (isdigit (*tokptr) || *tokptr == '_')
1227     {
1228       if (*tokptr != '_')
1229         {
1230           *copy++ = *tokptr;
1231         }
1232       tokptr++;
1233     }
1234
1235   /* Now accept either a '.', or one of [eEdD].  Dot is legal regardless
1236      of whether we found any leading digits, and we simply accept it and
1237      continue on to look for the fractional part and/or exponent.  One of
1238      [eEdD] is legal only if we have seen digits, and means that there
1239      is no fractional part.  If we find neither of these, then this is
1240      not a floating point number, so return failure. */
1241
1242   switch (*tokptr++)
1243     {
1244       case '.':
1245         /* Accept and then look for fractional part and/or exponent. */
1246         *copy++ = '.';
1247         break;
1248
1249       case 'e':
1250       case 'E':
1251       case 'd':
1252       case 'D':
1253         if (copy == buf)
1254           {
1255             return (0);
1256           }
1257         *copy++ = 'e';
1258         goto collect_exponent;
1259         break;
1260
1261       default:
1262         return (0);
1263         break;
1264     }
1265
1266   /* We found a '.', copy any fractional digits to the conversion buffer, up
1267      to the first nondigit, non-underscore character. */
1268
1269   while (isdigit (*tokptr) || *tokptr == '_')
1270     {
1271       if (*tokptr != '_')
1272         {
1273           *copy++ = *tokptr;
1274         }
1275       tokptr++;
1276     }
1277
1278   /* Look for an exponent, which must start with one of [eEdD].  If none
1279      is found, jump directly to trying to convert what we have collected
1280      so far. */
1281
1282   switch (*tokptr)
1283     {
1284       case 'e':
1285       case 'E':
1286       case 'd':
1287       case 'D':
1288         *copy++ = 'e';
1289         tokptr++;
1290         break;
1291       default:
1292         goto convert_float;
1293         break;
1294     }
1295
1296   /* Accept an optional '-' or '+' following one of [eEdD]. */
1297
1298   collect_exponent:
1299   if (*tokptr == '+' || *tokptr == '-')
1300     {
1301       *copy++ = *tokptr++;
1302     }
1303
1304   /* Now copy an exponent into the conversion buffer.  Note that at the
1305      moment underscores are *not* allowed in exponents. */
1306
1307   while (isdigit (*tokptr))
1308     {
1309       *copy++ = *tokptr++;
1310     }
1311
1312   /* If we transfered any chars to the conversion buffer, try to interpret its
1313      contents as a floating point value.  If any characters remain, then we
1314      must not have a valid floating point string. */
1315
1316   convert_float:
1317   *copy = '\0';
1318   if (copy != buf)
1319       {
1320         dval = strtod (buf, &copy);
1321         if (*copy == '\0')
1322           {
1323             yylval.dval = dval;
1324             lexptr = tokptr;
1325             return (FLOAT_LITERAL);
1326           }
1327       }
1328   return (0);
1329 }
1330
1331 /* Recognize a string literal.  A string literal is a nonzero sequence
1332    of characters enclosed in matching single or double quotes, except that
1333    a single character inside single quotes is a character literal, which
1334    we reject as a string literal.  To embed the terminator character inside
1335    a string, it is simply doubled (I.E. "this""is""one""string") */
1336
1337 static int
1338 match_string_literal ()
1339 {
1340   char *tokptr = lexptr;
1341
1342   for (tempbufindex = 0, tokptr++; *tokptr != '\0'; tokptr++)
1343     {
1344       CHECKBUF (1);
1345       if (*tokptr == *lexptr)
1346         {
1347           if (*(tokptr + 1) == *lexptr)
1348             {
1349               tokptr++;
1350             }
1351           else
1352             {
1353               break;
1354             }
1355         }
1356       tempbuf[tempbufindex++] = *tokptr;
1357     }
1358   if (*tokptr == '\0'                                   /* no terminator */
1359       || tempbufindex == 0                              /* no string */
1360       || (tempbufindex == 1 && *tokptr == '\''))        /* char literal */
1361     {
1362       return (0);
1363     }
1364   else
1365     {
1366       tempbuf[tempbufindex] = '\0';
1367       yylval.sval.ptr = tempbuf;
1368       yylval.sval.length = tempbufindex;
1369       lexptr = ++tokptr;
1370       return (CHARACTER_STRING_LITERAL);
1371     }
1372 }
1373
1374 /* Recognize a character literal.  A character literal is single character
1375    or a control sequence, enclosed in single quotes.  A control sequence
1376    is a comma separated list of one or more integer literals, enclosed
1377    in parenthesis and introduced with a circumflex character.
1378
1379    EX:  'a'  '^(7)'  '^(7,8)'
1380
1381    As a GNU chill extension, the syntax C'xx' is also recognized as a
1382    character literal, where xx is a hex value for the character.
1383
1384    Note that more than a single character, enclosed in single quotes, is
1385    a string literal.
1386
1387    Also note that the control sequence form is not in GNU Chill since it
1388    is ambiguous with the string literal form using single quotes.  I.E.
1389    is '^(7)' a character literal or a string literal.  In theory it it
1390    possible to tell by context, but GNU Chill doesn't accept the control
1391    sequence form, so neither do we (for now the code is disabled).
1392
1393    Returns CHARACTER_LITERAL if a match is found.
1394    */
1395
1396 static int
1397 match_character_literal ()
1398 {
1399   char *tokptr = lexptr;
1400   int ival = 0;
1401
1402   if ((tolower (*tokptr) == 'c') && (*(tokptr + 1) == '\''))
1403     {
1404       /* We have a GNU chill extension form, so skip the leading "C'",
1405          decode the hex value, and then ensure that we have a trailing
1406          single quote character. */
1407       tokptr += 2;
1408       if (!decode_integer_value (16, &tokptr, &ival) || (*tokptr != '\''))
1409         {
1410           return (0);
1411         }
1412       tokptr++;
1413     }
1414   else if (*tokptr == '\'')
1415     {
1416       tokptr++;
1417
1418       /* Determine which form we have, either a control sequence or the
1419          single character form. */
1420
1421       if ((*tokptr == '^') && (*(tokptr + 1) == '('))
1422         {
1423           return (0);  /* Disable, see note above. */
1424           /* Match and decode a control sequence.  Return zero if we don't
1425              find a valid integer literal, or if the next unconsumed character
1426              after the integer literal is not the trailing ')'.
1427              FIXME:  We currently don't handle the multiple integer literal
1428              form. */
1429           tokptr += 2;
1430           if (!decode_integer_literal (&ival, &tokptr) || (*tokptr++ != ')'))
1431             {
1432               return (0);
1433             }
1434         }
1435       else
1436         {
1437           ival = *tokptr++;
1438         }
1439
1440       /* The trailing quote has not yet been consumed.  If we don't find
1441          it, then we have no match. */
1442
1443       if (*tokptr++ != '\'')
1444         {
1445           return (0);
1446         }
1447     }
1448   else
1449     {
1450       /* Not a character literal. */
1451       return (0);
1452     }
1453   yylval.typed_val.val = ival;
1454   yylval.typed_val.type = builtin_type_chill_char;
1455   lexptr = tokptr;
1456   return (CHARACTER_LITERAL);
1457 }
1458
1459 /* Recognize an integer literal, as specified in Z.200 sec 5.2.4.2.
1460    Note that according to 5.2.4.2, a single "_" is also a valid integer
1461    literal, however GNU-chill requires there to be at least one "digit"
1462    in any integer literal. */
1463
1464 static int
1465 match_integer_literal ()
1466 {
1467   char *tokptr = lexptr;
1468   int ival;
1469
1470   if (!decode_integer_literal (&ival, &tokptr))
1471     {
1472       return (0);
1473     }
1474   else
1475     {
1476       yylval.typed_val.val = ival;
1477       yylval.typed_val.type = builtin_type_int;
1478       lexptr = tokptr;
1479       return (INTEGER_LITERAL);
1480     }
1481 }
1482
1483 /* Recognize a bit-string literal, as specified in Z.200 sec 5.2.4.8
1484    Note that according to 5.2.4.8, a single "_" is also a valid bit-string
1485    literal, however GNU-chill requires there to be at least one "digit"
1486    in any bit-string literal. */
1487
1488 static int
1489 match_bitstring_literal ()
1490 {
1491   char *tokptr = lexptr;
1492   int mask;
1493   int bitoffset = 0;
1494   int bitcount = 0;
1495   int base;
1496   int digit;
1497
1498   tempbufindex = 0;
1499
1500   /* Look for the required explicit base specifier. */
1501
1502   switch (*tokptr++)
1503     {
1504     case 'b':
1505     case 'B':
1506       base = 2;
1507       break;
1508     case 'o':
1509     case 'O':
1510       base = 8;
1511       break;
1512     case 'h':
1513     case 'H':
1514       base = 16;
1515       break;
1516     default:
1517       return (0);
1518       break;
1519     }
1520
1521   /* Ensure that the character after the explicit base is a single quote. */
1522
1523   if (*tokptr++ != '\'')
1524     {
1525       return (0);
1526     }
1527
1528   while (*tokptr != '\0' && *tokptr != '\'')
1529     {
1530       digit = tolower (*tokptr);
1531       tokptr++;
1532       switch (digit)
1533         {
1534           case '_':
1535             continue;
1536           case '0':  case '1':  case '2':  case '3':  case '4':
1537           case '5':  case '6':  case '7':  case '8':  case '9':
1538             digit -= '0';
1539             break;
1540           case 'a':  case 'b':  case 'c':  case 'd':  case 'e': case 'f':
1541             digit -= 'a';
1542             digit += 10;
1543             break;
1544           default:
1545             return (0);
1546             break;
1547         }
1548       if (digit >= base)
1549         {
1550           /* Found something not in domain for current base. */
1551           return (0);
1552         }
1553       else
1554         {
1555           /* Extract bits from digit, starting with the msbit appropriate for
1556              the current base, and packing them into the bitstring byte,
1557              starting at the lsbit. */
1558           for (mask = (base >> 1); mask > 0; mask >>= 1)
1559             {
1560               bitcount++;
1561               CHECKBUF (1);
1562               if (digit & mask)
1563                 {
1564                   tempbuf[tempbufindex] |= (1 << bitoffset);
1565                 }
1566               bitoffset++;
1567               if (bitoffset == HOST_CHAR_BIT)
1568                 {
1569                   bitoffset = 0;
1570                   tempbufindex++;
1571                 }
1572             }
1573         }
1574     }
1575
1576   /* Verify that we consumed everything up to the trailing single quote,
1577      and that we found some bits (IE not just underbars). */
1578
1579   if (*tokptr++ != '\'')
1580     {
1581       return (0);
1582     }
1583   else
1584     {
1585       yylval.sval.ptr = tempbuf;
1586       yylval.sval.length = bitcount;
1587       lexptr = tokptr;
1588       return (BIT_STRING_LITERAL);
1589     }
1590 }
1591
1592 /* Recognize tokens that start with '$'.  These include:
1593
1594         $regname        A native register name or a "standard
1595                         register name".
1596                         Return token GDB_REGNAME.
1597
1598         $variable       A convenience variable with a name chosen
1599                         by the user.
1600                         Return token GDB_VARIABLE.
1601
1602         $digits         Value history with index <digits>, starting
1603                         from the first value which has index 1.
1604                         Return GDB_LAST.
1605
1606         $$digits        Value history with index <digits> relative
1607                         to the last value.  I.E. $$0 is the last
1608                         value, $$1 is the one previous to that, $$2
1609                         is the one previous to $$1, etc.
1610                         Return token GDB_LAST.
1611
1612         $ | $0 | $$0    The last value in the value history.
1613                         Return token GDB_LAST.
1614
1615         $$              An abbreviation for the second to the last
1616                         value in the value history, I.E. $$1
1617                         Return token GDB_LAST.
1618
1619     Note that we currently assume that register names and convenience
1620     variables follow the convention of starting with a letter or '_'.
1621
1622    */
1623
1624 static int
1625 match_dollar_tokens ()
1626 {
1627   char *tokptr;
1628   int regno;
1629   int namelength;
1630   int negate;
1631   int ival;
1632
1633   /* We will always have a successful match, even if it is just for
1634      a single '$', the abbreviation for $$0.  So advance lexptr. */
1635
1636   tokptr = ++lexptr;
1637
1638   if (*tokptr == '_' || isalpha (*tokptr))
1639     {
1640       /* Look for a match with a native register name, usually something
1641          like "r0" for example. */
1642
1643       for (regno = 0; regno < NUM_REGS; regno++)
1644         {
1645           namelength = strlen (reg_names[regno]);
1646           if (STREQN (tokptr, reg_names[regno], namelength)
1647               && !isalnum (tokptr[namelength]))
1648             {
1649               yylval.lval = regno;
1650               lexptr += namelength + 1;
1651               return (GDB_REGNAME);
1652             }
1653         }
1654
1655       /* Look for a match with a standard register name, usually something
1656          like "pc", which gdb always recognizes as the program counter
1657          regardless of what the native register name is. */
1658
1659       for (regno = 0; regno < num_std_regs; regno++)
1660         {
1661           namelength = strlen (std_regs[regno].name);
1662           if (STREQN (tokptr, std_regs[regno].name, namelength)
1663               && !isalnum (tokptr[namelength]))
1664             {
1665               yylval.lval = std_regs[regno].regnum;
1666               lexptr += namelength;
1667               return (GDB_REGNAME);
1668             }
1669         }
1670
1671       /* Attempt to match against a convenience variable.  Note that
1672          this will always succeed, because if no variable of that name
1673          already exists, the lookup_internalvar will create one for us.
1674          Also note that both lexptr and tokptr currently point to the
1675          start of the input string we are trying to match, and that we
1676          have already tested the first character for non-numeric, so we
1677          don't have to treat it specially. */
1678
1679       while (*tokptr == '_' || isalnum (*tokptr))
1680         {
1681           tokptr++;
1682         }
1683       yylval.sval.ptr = lexptr;
1684       yylval.sval.length = tokptr - lexptr;
1685       yylval.ivar = lookup_internalvar (copy_name (yylval.sval));
1686       lexptr = tokptr;
1687       return (GDB_VARIABLE);
1688     }
1689
1690   /* Since we didn't match against a register name or convenience
1691      variable, our only choice left is a history value. */
1692
1693   if (*tokptr == '$')
1694     {
1695       negate = 1;
1696       ival = 1;
1697       tokptr++;
1698     }
1699   else
1700     {
1701       negate = 0;
1702       ival = 0;
1703     }
1704
1705   /* Attempt to decode more characters as an integer value giving
1706      the index in the history list.  If successful, the value will
1707      overwrite ival (currently 0 or 1), and if not, ival will be
1708      left alone, which is good since it is currently correct for
1709      the '$' or '$$' case. */
1710
1711   decode_integer_literal (&ival, &tokptr);
1712   yylval.lval = negate ? -ival : ival;
1713   lexptr = tokptr;
1714   return (GDB_LAST);
1715 }
1716
1717 struct token
1718 {
1719   char *operator;
1720   int token;
1721 };
1722
1723 static const struct token tokentab6[] =
1724 {
1725     { "LENGTH", LENGTH }
1726 };
1727
1728 static const struct token tokentab5[] =
1729 {
1730     { "LOWER", LOWER },
1731     { "UPPER", UPPER },
1732     { "ANDIF", ANDIF }
1733 };
1734
1735 static const struct token tokentab4[] =
1736 {
1737     { "PRED", PRED },
1738     { "SUCC", SUCC },
1739     { "CARD", CARD },
1740     { "SIZE", SIZE },
1741     { "ORIF", ORIF }
1742 };
1743
1744 static const struct token tokentab3[] =
1745 {
1746     { "NUM", NUM },
1747     { "ABS", ABS },
1748     { "MAX", MAX },
1749     { "MIN", MIN },
1750     { "MOD", MOD },
1751     { "REM", REM },
1752     { "NOT", NOT },
1753     { "XOR", LOGXOR },
1754     { "AND", LOGAND }
1755 };
1756
1757 static const struct token tokentab2[] =
1758 {
1759     { ":=", GDB_ASSIGNMENT },
1760     { "//", SLASH_SLASH },
1761     { "/=", NOTEQUAL },
1762     { "<=", LEQ },
1763     { ">=", GTR },
1764     { "IN", IN },
1765     { "OR", LOGIOR }
1766 };
1767
1768 /* Read one token, getting characters through lexptr.  */
1769 /* This is where we will check to make sure that the language and the
1770    operators used are compatible.  */
1771
1772 static int
1773 yylex ()
1774 {
1775     unsigned int i;
1776     int token;
1777     char *simplename;
1778     struct symbol *sym;
1779
1780     /* Skip over any leading whitespace. */
1781     while (isspace (*lexptr))
1782         {
1783             lexptr++;
1784         }
1785     /* Look for special single character cases which can't be the first
1786        character of some other multicharacter token. */
1787     switch (*lexptr)
1788         {
1789             case '\0':
1790                 return (0);
1791             case ',':
1792             case '=':
1793             case ';':
1794             case '!':
1795             case '+':
1796             case '-':
1797             case '*':
1798             case '(':
1799             case ')':
1800             case '[':
1801             case ']':
1802                 return (*lexptr++);
1803         }
1804     /* Look for characters which start a particular kind of multicharacter
1805        token, such as a character literal, register name, convenience
1806        variable name, string literal, etc. */
1807     switch (*lexptr)
1808       {
1809         case '\'':
1810         case '\"':
1811           /* First try to match a string literal, which is any nonzero
1812              sequence of characters enclosed in matching single or double
1813              quotes, except that a single character inside single quotes
1814              is a character literal, so we have to catch that case also. */
1815           token = match_string_literal ();
1816           if (token != 0)
1817             {
1818               return (token);
1819             }
1820           if (*lexptr == '\'')
1821             {
1822               token = match_character_literal ();
1823               if (token != 0)
1824                 {
1825                   return (token);
1826                 }
1827             }
1828           break;
1829         case 'C':
1830         case 'c':
1831           token = match_character_literal ();
1832           if (token != 0)
1833             {
1834               return (token);
1835             }
1836           break;
1837         case '$':
1838           token = match_dollar_tokens ();
1839           if (token != 0)
1840             {
1841               return (token);
1842             }
1843           break;
1844       }
1845     /* See if it is a special token of length 6.  */
1846     for (i = 0; i < sizeof (tokentab6) / sizeof (tokentab6[0]); i++)
1847         {
1848             if (STREQN (lexptr, tokentab6[i].operator, 6))
1849                 {
1850                     lexptr += 6;
1851                     return (tokentab6[i].token);
1852                 }
1853         }
1854     /* See if it is a special token of length 5.  */
1855     for (i = 0; i < sizeof (tokentab5) / sizeof (tokentab5[0]); i++)
1856         {
1857             if (STREQN (lexptr, tokentab5[i].operator, 5))
1858                 {
1859                     lexptr += 5;
1860                     return (tokentab5[i].token);
1861                 }
1862         }
1863     /* See if it is a special token of length 4.  */
1864     for (i = 0; i < sizeof (tokentab4) / sizeof (tokentab4[0]); i++)
1865         {
1866             if (STREQN (lexptr, tokentab4[i].operator, 4))
1867                 {
1868                     lexptr += 4;
1869                     return (tokentab4[i].token);
1870                 }
1871         }
1872     /* See if it is a special token of length 3.  */
1873     for (i = 0; i < sizeof (tokentab3) / sizeof (tokentab3[0]); i++)
1874         {
1875             if (STREQN (lexptr, tokentab3[i].operator, 3))
1876                 {
1877                     lexptr += 3;
1878                     return (tokentab3[i].token);
1879                 }
1880         }
1881     /* See if it is a special token of length 2.  */
1882     for (i = 0; i < sizeof (tokentab2) / sizeof (tokentab2[0]); i++)
1883         {
1884             if (STREQN (lexptr, tokentab2[i].operator, 2))
1885                 {
1886                     lexptr += 2;
1887                     return (tokentab2[i].token);
1888                 }
1889         }
1890     /* Look for single character cases which which could be the first
1891        character of some other multicharacter token, but aren't, or we
1892        would already have found it. */
1893     switch (*lexptr)
1894         {
1895             case ':':
1896             case '/':
1897             case '<':
1898             case '>':
1899                 return (*lexptr++);
1900         }
1901     /* Look for other special tokens. */
1902     if (STREQN (lexptr, "TRUE", 4)) /* FIXME:  What about lowercase? */
1903         {
1904             yylval.ulval = 1;
1905             lexptr += 4;
1906             return (BOOLEAN_LITERAL);
1907         }
1908     if (STREQN (lexptr, "FALSE", 5)) /* FIXME:  What about lowercase? */
1909         {
1910             yylval.ulval = 0;
1911             lexptr += 5;
1912             return (BOOLEAN_LITERAL);
1913         }
1914     /* Look for a float literal before looking for an integer literal, so
1915        we match as much of the input stream as possible. */
1916     token = match_float_literal ();
1917     if (token != 0)
1918         {
1919             return (token);
1920         }
1921     token = match_bitstring_literal ();
1922     if (token != 0)
1923         {
1924             return (token);
1925         }
1926     token = match_integer_literal ();
1927     if (token != 0)
1928         {
1929             return (token);
1930         }
1931
1932     /* Try to match a simple name string, and if a match is found, then
1933        further classify what sort of name it is and return an appropriate
1934        token.  Note that attempting to match a simple name string consumes
1935        the token from lexptr, so we can't back out if we later find that
1936        we can't classify what sort of name it is. */
1937
1938     simplename = match_simple_name_string ();
1939     if (simplename != NULL)
1940       {
1941         sym = lookup_symbol (simplename, expression_context_block,
1942                              VAR_NAMESPACE, (int *) NULL,
1943                              (struct symtab **) NULL);
1944         if (sym != NULL)
1945           {
1946             yylval.ssym.stoken.ptr = NULL;
1947             yylval.ssym.stoken.length = 0;
1948             yylval.ssym.sym = sym;
1949             yylval.ssym.is_a_field_of_this = 0; /* FIXME, C++'ism */
1950             switch (SYMBOL_CLASS (sym))
1951               {
1952               case LOC_BLOCK:
1953                 /* Found a procedure name. */
1954                 return (GENERAL_PROCEDURE_NAME);
1955               case LOC_STATIC:
1956                 /* Found a global or local static variable. */
1957                 return (LOCATION_NAME);
1958               case LOC_REGISTER:
1959               case LOC_ARG:
1960               case LOC_REF_ARG:
1961               case LOC_REGPARM:
1962               case LOC_LOCAL:
1963               case LOC_LOCAL_ARG:
1964                 if (innermost_block == NULL
1965                     || contained_in (block_found, innermost_block))
1966                   {
1967                     innermost_block = block_found;
1968                   }
1969                 return (LOCATION_NAME);
1970                 break;
1971               case LOC_CONST:
1972               case LOC_LABEL:
1973                 return (LOCATION_NAME);
1974                 break;
1975               case LOC_UNDEF:
1976               case LOC_TYPEDEF:
1977               case LOC_CONST_BYTES:
1978                 error ("Symbol \"%s\" names no location.", simplename);
1979                 break;
1980               }
1981           }
1982         else if (!have_full_symbols () && !have_partial_symbols ())
1983           {
1984             error ("No symbol table is loaded.  Use the \"file\" command.");
1985           }
1986         else
1987           {
1988             error ("No symbol \"%s\" in current context.", simplename);
1989           }
1990       }
1991
1992     /* Catch single character tokens which are not part of some
1993        longer token. */
1994
1995     switch (*lexptr)
1996       {
1997         case '.':                       /* Not float for example. */
1998           return (*lexptr++);
1999       }
2000
2001     return (ILLEGAL_TOKEN);
2002 }
2003
2004 void
2005 yyerror (msg)
2006      char *msg; /* unused */
2007 {
2008   printf ("Parsing:  %s\n", lexptr);
2009   if (yychar < 256)
2010     {
2011       error ("Invalid syntax in expression near character '%c'.", yychar);
2012     }
2013   else
2014     {
2015       error ("Invalid syntax in expression");
2016     }
2017 }