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