gdb/ch-exp.y

   1 /* YACC grammar for Chill expressions, for GDB.
   2    Copyright 1992, 1993 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 #include "bfd.h" /* Required by objfiles.h.  */
  64 #include "symfile.h" /* Required by objfiles.h.  */
  65 #include "objfiles.h" /* For have_full_symbols and have_partial_symbols */
  66
  67 /* Remap normal yacc parser interface names (yyparse, yylex, yyerror, etc),
  68    as well as gratuitiously global symbol names, so we can have multiple
  69    yacc generated parsers in gdb.  Note that these are only the variables
  70    produced by yacc.  If other parser generators (bison, byacc, etc) produce
  71    additional global names that conflict at link time, then those parser
  72    generators need to be fixed instead of adding those names to this list. */
  73
  74 #define yymaxdepth chill_maxdepth
  75 #define yyparse chill_parse
  76 #define yylex   chill_lex
  77 #define yyerror chill_error
  78 #define yylval  chill_lval
  79 #define yychar  chill_char
  80 #define yydebug chill_debug
  81 #define yypact  chill_pact
  82 #define yyr1    chill_r1
  83 #define yyr2    chill_r2
  84 #define yydef   chill_def
  85 #define yychk   chill_chk
  86 #define yypgo   chill_pgo
  87 #define yyact   chill_act
  88 #define yyexca  chill_exca
  89 #define yyerrflag chill_errflag
  90 #define yynerrs chill_nerrs
  91 #define yyps    chill_ps
  92 #define yypv    chill_pv
  93 #define yys     chill_s
  94 #define yy_yys  chill_yys
  95 #define yystate chill_state
  96 #define yytmp   chill_tmp
  97 #define yyv     chill_v
  98 #define yy_yyv  chill_yyv
  99 #define yyval   chill_val
 100 #define yylloc  chill_lloc
 101 #define yyreds  chill_reds              /* With YYDEBUG defined */
 102 #define yytoks  chill_toks              /* With YYDEBUG defined */
 103
 104 #ifndef YYDEBUG
 105 #define YYDEBUG 0               /* Default to no yydebug support */
 106 #endif
 107
 108 int
 109 yyparse PARAMS ((void));
 110
 111 static int
 112 yylex PARAMS ((void));
 113
 114 void
 115 yyerror PARAMS ((char *));
 116
 117 %}
 118
 119 /* Although the yacc "value" of an expression is not used,
 120    since the result is stored in the structure being created,
 121    other node types do have values.  */
 122
 123 %union
 124   {
 125     LONGEST lval;
 126     unsigned LONGEST ulval;
 127     struct {
 128       LONGEST val;
 129       struct type *type;
 130     } typed_val;
 131     double dval;
 132     struct symbol *sym;
 133     struct type *tval;
 134     struct stoken sval;
 135     struct ttype tsym;
 136     struct symtoken ssym;
 137     int voidval;
 138     struct block *bval;
 139     enum exp_opcode opcode;
 140     struct internalvar *ivar;
 141
 142     struct type **tvec;
 143     int *ivec;
 144   }
 145
 146 %token <voidval> FIXME_01
 147 %token <voidval> FIXME_02
 148 %token <voidval> FIXME_03
 149 %token <voidval> FIXME_04
 150 %token <voidval> FIXME_05
 151 %token <voidval> FIXME_06
 152 %token <voidval> FIXME_07
 153 %token <voidval> FIXME_08
 154 %token <voidval> FIXME_09
 155 %token <voidval> FIXME_10
 156 %token <voidval> FIXME_11
 157 %token <voidval> FIXME_12
 158 %token <voidval> FIXME_13
 159 %token <voidval> FIXME_14
 160 %token <voidval> FIXME_15
 161 %token <voidval> FIXME_16
 162 %token <voidval> FIXME_17
 163 %token <voidval> FIXME_18
 164 %token <voidval> FIXME_19
 165 %token <voidval> FIXME_20
 166 %token <voidval> FIXME_21
 167 %token <voidval> FIXME_22
 168 %token <voidval> FIXME_24
 169 %token <voidval> FIXME_25
 170 %token <voidval> FIXME_26
 171 %token <voidval> FIXME_27
 172 %token <voidval> FIXME_28
 173 %token <voidval> FIXME_29
 174 %token <voidval> FIXME_30
 175
 176 %token <typed_val>      INTEGER_LITERAL
 177 %token <ulval>          BOOLEAN_LITERAL
 178 %token <typed_val>      CHARACTER_LITERAL
 179 %token <dval>           FLOAT_LITERAL
 180 %token <ssym>           GENERAL_PROCEDURE_NAME
 181 %token <ssym>           LOCATION_NAME
 182 %token <voidval>        SET_LITERAL
 183 %token <voidval>        EMPTINESS_LITERAL
 184 %token <sval>           CHARACTER_STRING_LITERAL
 185 %token <sval>           BIT_STRING_LITERAL
 186 %token <tsym>           TYPENAME
 187 %token <sval>           FIELD_NAME
 188
 189 %token <voidval>        '.'
 190 %token <voidval>        ';'
 191 %token <voidval>        ':'
 192 %token <voidval>        CASE
 193 %token <voidval>        OF
 194 %token <voidval>        ESAC
 195 %token <voidval>        LOGIOR
 196 %token <voidval>        ORIF
 197 %token <voidval>        LOGXOR
 198 %token <voidval>        LOGAND
 199 %token <voidval>        ANDIF
 200 %token <voidval>        '='
 201 %token <voidval>        NOTEQUAL
 202 %token <voidval>        '>'
 203 %token <voidval>        GTR
 204 %token <voidval>        '<'
 205 %token <voidval>        LEQ
 206 %token <voidval>        IN
 207 %token <voidval>        '+'
 208 %token <voidval>        '-'
 209 %token <voidval>        '*'
 210 %token <voidval>        '/'
 211 %token <voidval>        SLASH_SLASH
 212 %token <voidval>        MOD
 213 %token <voidval>        REM
 214 %token <voidval>        NOT
 215 %token <voidval>        POINTER
 216 %token <voidval>        RECEIVE
 217 %token <voidval>        '['
 218 %token <voidval>        ']'
 219 %token <voidval>        '('
 220 %token <voidval>        ')'
 221 %token <voidval>        UP
 222 %token <voidval>        IF
 223 %token <voidval>        THEN
 224 %token <voidval>        ELSE
 225 %token <voidval>        FI
 226 %token <voidval>        ELSIF
 227 %token <voidval>        ILLEGAL_TOKEN
 228 %token <voidval>        NUM
 229 %token <voidval>        PRED
 230 %token <voidval>        SUCC
 231 %token <voidval>        ABS
 232 %token <voidval>        CARD
 233 %token <voidval>        MAX_TOKEN
 234 %token <voidval>        MIN_TOKEN
 235 %token <voidval>        SIZE
 236 %token <voidval>        UPPER
 237 %token <voidval>        LOWER
 238 %token <voidval>        LENGTH
 239
 240 /* Tokens which are not Chill tokens used in expressions, but rather GDB
 241    specific things that we recognize in the same context as Chill tokens
 242    (register names for example). */
 243
 244 %token <lval>           GDB_REGNAME     /* Machine register name */
 245 %token <lval>           GDB_LAST        /* Value history */
 246 %token <ivar>           GDB_VARIABLE    /* Convenience variable */
 247 %token <voidval>        GDB_ASSIGNMENT  /* Assign value to somewhere */
 248
 249 %type <voidval>         location
 250 %type <voidval>         access_name
 251 %type <voidval>         primitive_value
 252 %type <voidval>         location_contents
 253 %type <voidval>         value_name
 254 %type <voidval>         literal
 255 %type <voidval>         tuple
 256 %type <voidval>         value_string_element
 257 %type <voidval>         value_string_slice
 258 %type <voidval>         value_array_element
 259 %type <voidval>         value_array_slice
 260 %type <voidval>         value_structure_field
 261 %type <voidval>         expression_conversion
 262 %type <voidval>         value_procedure_call
 263 %type <voidval>         value_built_in_routine_call
 264 %type <voidval>         chill_value_built_in_routine_call
 265 %type <voidval>         start_expression
 266 %type <voidval>         zero_adic_operator
 267 %type <voidval>         parenthesised_expression
 268 %type <voidval>         value
 269 %type <voidval>         undefined_value
 270 %type <voidval>         expression
 271 %type <voidval>         conditional_expression
 272 %type <voidval>         then_alternative
 273 %type <voidval>         else_alternative
 274 %type <voidval>         sub_expression
 275 %type <voidval>         value_case_alternative
 276 %type <voidval>         operand_0
 277 %type <voidval>         operand_1
 278 %type <voidval>         operand_2
 279 %type <voidval>         operand_3
 280 %type <voidval>         operand_4
 281 %type <voidval>         operand_5
 282 %type <voidval>         operand_6
 283 %type <voidval>         synonym_name
 284 %type <voidval>         value_enumeration_name
 285 %type <voidval>         value_do_with_name
 286 %type <voidval>         value_receive_name
 287 %type <voidval>         string_primitive_value
 288 %type <voidval>         start_element
 289 %type <voidval>         left_element
 290 %type <voidval>         right_element
 291 %type <voidval>         slice_size
 292 %type <voidval>         array_primitive_value
 293 %type <voidval>         expression_list
 294 %type <voidval>         lower_element
 295 %type <voidval>         upper_element
 296 %type <voidval>         first_element
 297 %type <voidval>         mode_argument
 298 %type <voidval>         upper_lower_argument
 299 %type <voidval>         length_argument
 300 %type <voidval>         array_mode_name
 301 %type <voidval>         string_mode_name
 302 %type <voidval>         variant_structure_mode_name
 303 %type <voidval>         boolean_expression
 304 %type <voidval>         case_selector_list
 305 %type <voidval>         subexpression
 306 %type <voidval>         case_label_specification
 307 %type <voidval>         buffer_location
 308 %type <voidval>         single_assignment_action
 309 %type <tsym>            mode_name
 310
 311 %%
 312
 313 /* Z.200, 5.3.1 */
 314
 315 start   :       value { }
 316         |       mode_name
 317                         { write_exp_elt_opcode(OP_TYPE);
 318                           write_exp_elt_type($1.type);
 319                           write_exp_elt_opcode(OP_TYPE);}
 320         ;
 321
 322 value           :       expression
 323                         {
 324                           $$ = 0;       /* FIXME */
 325                         }
 326                 |       undefined_value
 327                         {
 328                           $$ = 0;       /* FIXME */
 329                         }
 330                 ;
 331
 332 undefined_value :       FIXME_01
 333                         {
 334                           $$ = 0;       /* FIXME */
 335                         }
 336                 ;
 337
 338 /* Z.200, 4.2.1 */
 339
 340 location        :       access_name
 341                 |       primitive_value POINTER
 342                         {
 343                           write_exp_elt_opcode (UNOP_IND);
 344                         }
 345                 ;
 346
 347 /* Z.200, 4.2.2 */
 348
 349 access_name     :       LOCATION_NAME
 350                         {
 351                           write_exp_elt_opcode (OP_VAR_VALUE);
 352                           write_exp_elt_block (NULL);
 353                           write_exp_elt_sym ($1.sym);
 354                           write_exp_elt_opcode (OP_VAR_VALUE);
 355                         }
 356                 |       GDB_LAST                /* gdb specific */
 357                         {
 358                           write_exp_elt_opcode (OP_LAST);
 359                           write_exp_elt_longcst ($1);
 360                           write_exp_elt_opcode (OP_LAST);
 361                         }
 362                 |       GDB_REGNAME             /* gdb specific */
 363                         {
 364                           write_exp_elt_opcode (OP_REGISTER);
 365                           write_exp_elt_longcst ($1);
 366                           write_exp_elt_opcode (OP_REGISTER);
 367                         }
 368                 |       GDB_VARIABLE    /* gdb specific */
 369                         {
 370                           write_exp_elt_opcode (OP_INTERNALVAR);
 371                           write_exp_elt_intern ($1);
 372                           write_exp_elt_opcode (OP_INTERNALVAR);
 373                         }
 374                 |       FIXME_03
 375                         {
 376                           $$ = 0;       /* FIXME */
 377                         }
 378                 ;
 379
 380 /* Z.200, 4.2.8 */
 381
 382 expression_list :       expression
 383                         {
 384                           arglist_len = 1;
 385                         }
 386                 |       expression_list ',' expression
 387                         {
 388                           arglist_len++;
 389                         }
 390
 391 /* Z.200, 5.2.1 */
 392
 393 primitive_value :       location_contents
 394                         {
 395                           $$ = 0;       /* FIXME */
 396                         }
 397                 |       value_name
 398                         {
 399                           $$ = 0;       /* FIXME */
 400                         }
 401                 |       literal
 402                         {
 403                           $$ = 0;       /* FIXME */
 404                         }
 405                 |       tuple
 406                         {
 407                           $$ = 0;       /* FIXME */
 408                         }
 409                 |       value_string_element
 410                         {
 411                           $$ = 0;       /* FIXME */
 412                         }
 413                 |       value_string_slice
 414                         {
 415                           $$ = 0;       /* FIXME */
 416                         }
 417                 |       value_array_element
 418                         {
 419                           $$ = 0;       /* FIXME */
 420                         }
 421                 |       value_array_slice
 422                         {
 423                           $$ = 0;       /* FIXME */
 424                         }
 425                 |       value_structure_field
 426                         {
 427                           $$ = 0;       /* FIXME */
 428                         }
 429                 |       expression_conversion
 430                         {
 431                           $$ = 0;       /* FIXME */
 432                         }
 433                 |       value_procedure_call
 434                         {
 435                           $$ = 0;       /* FIXME */
 436                         }
 437                 |       value_built_in_routine_call
 438                         {
 439                           $$ = 0;       /* FIXME */
 440                         }
 441                 |       start_expression
 442                         {
 443                           $$ = 0;       /* FIXME */
 444                         }
 445                 |       zero_adic_operator
 446                         {
 447                           $$ = 0;       /* FIXME */
 448                         }
 449                 |       parenthesised_expression
 450                         {
 451                           $$ = 0;       /* FIXME */
 452                         }
 453                 ;
 454
 455 /* Z.200, 5.2.2 */
 456
 457 location_contents:      location
 458                         {
 459                           $$ = 0;       /* FIXME */
 460                         }
 461                 ;
 462
 463 /* Z.200, 5.2.3 */
 464
 465 value_name      :       synonym_name
 466                         {
 467                           $$ = 0;       /* FIXME */
 468                         }
 469                 |       value_enumeration_name
 470                         {
 471                           $$ = 0;       /* FIXME */
 472                         }
 473                 |       value_do_with_name
 474                         {
 475                           $$ = 0;       /* FIXME */
 476                         }
 477                 |       value_receive_name
 478                         {
 479                           $$ = 0;       /* FIXME */
 480                         }
 481                 |       GENERAL_PROCEDURE_NAME
 482                         {
 483                           write_exp_elt_opcode (OP_VAR_VALUE);
 484                           write_exp_elt_block (NULL);
 485                           write_exp_elt_sym ($1.sym);
 486                           write_exp_elt_opcode (OP_VAR_VALUE);
 487                         }
 488                 ;
 489
 490 /* Z.200, 5.2.4.1 */
 491
 492 literal         :       INTEGER_LITERAL
 493                         {
 494                           write_exp_elt_opcode (OP_LONG);
 495                           write_exp_elt_type ($1.type);
 496                           write_exp_elt_longcst ((LONGEST) ($1.val));
 497                           write_exp_elt_opcode (OP_LONG);
 498                         }
 499                 |       BOOLEAN_LITERAL
 500                         {
 501                           write_exp_elt_opcode (OP_BOOL);
 502                           write_exp_elt_longcst ((LONGEST) $1);
 503                           write_exp_elt_opcode (OP_BOOL);
 504                         }
 505                 |       CHARACTER_LITERAL
 506                         {
 507                           write_exp_elt_opcode (OP_LONG);
 508                           write_exp_elt_type ($1.type);
 509                           write_exp_elt_longcst ((LONGEST) ($1.val));
 510                           write_exp_elt_opcode (OP_LONG);
 511                         }
 512                 |       FLOAT_LITERAL
 513                         {
 514                           write_exp_elt_opcode (OP_DOUBLE);
 515                           write_exp_elt_type (builtin_type_double);
 516                           write_exp_elt_dblcst ($1);
 517                           write_exp_elt_opcode (OP_DOUBLE);
 518                         }
 519                 |       SET_LITERAL
 520                         {
 521                           $$ = 0;       /* FIXME */
 522                         }
 523                 |       EMPTINESS_LITERAL
 524                         {
 525                           $$ = 0;       /* FIXME */
 526                         }
 527                 |       CHARACTER_STRING_LITERAL
 528                         {
 529                           write_exp_elt_opcode (OP_STRING);
 530                           write_exp_string ($1);
 531                           write_exp_elt_opcode (OP_STRING);
 532                         }
 533                 |       BIT_STRING_LITERAL
 534                         {
 535                           write_exp_elt_opcode (OP_BITSTRING);
 536                           write_exp_bitstring ($1);
 537                           write_exp_elt_opcode (OP_BITSTRING);
 538                         }
 539                 ;
 540
 541 /* Z.200, 5.2.5 */
 542
 543 tuple           :       FIXME_04
 544                         {
 545                           $$ = 0;       /* FIXME */
 546                         }
 547                 ;
 548
 549
 550 /* Z.200, 5.2.6 */
 551
 552 value_string_element:   string_primitive_value '(' start_element ')'
 553                         {
 554                           $$ = 0;       /* FIXME */
 555                         }
 556                 ;
 557
 558 /* Z.200, 5.2.7 */
 559
 560 value_string_slice:     string_primitive_value '(' left_element ':' right_element ')'
 561                         {
 562                           $$ = 0;       /* FIXME */
 563                         }
 564                 |       string_primitive_value '(' start_element UP slice_size ')'
 565                         {
 566                           $$ = 0;       /* FIXME */
 567                         }
 568                 ;
 569
 570 /* Z.200, 5.2.8 */
 571
 572 value_array_element:    array_primitive_value '('
 573                                 /* This is to save the value of arglist_len
 574                                    being accumulated for each dimension. */
 575                                 { start_arglist (); }
 576                         expression_list ')'
 577                         {
 578                           write_exp_elt_opcode (MULTI_SUBSCRIPT);
 579                           write_exp_elt_longcst ((LONGEST) end_arglist ());
 580                           write_exp_elt_opcode (MULTI_SUBSCRIPT);
 581                         }
 582                 ;
 583
 584 /* Z.200, 5.2.9 */
 585
 586 value_array_slice:      array_primitive_value '(' lower_element ':' upper_element ')'
 587                         {
 588                           $$ = 0;       /* FIXME */
 589                         }
 590                 |       array_primitive_value '(' first_element UP slice_size ')'
 591                         {
 592                           $$ = 0;       /* FIXME */
 593                         }
 594                 ;
 595
 596 /* Z.200, 5.2.10 */
 597
 598 value_structure_field:  primitive_value FIELD_NAME
 599                         { write_exp_elt_opcode (STRUCTOP_STRUCT);
 600                           write_exp_string ($2);
 601                           write_exp_elt_opcode (STRUCTOP_STRUCT);
 602                         }
 603                 ;
 604
 605 /* Z.200, 5.2.11 */
 606
 607 expression_conversion:  mode_name parenthesised_expression
 608                         {
 609                           write_exp_elt_opcode (UNOP_CAST);
 610                           write_exp_elt_type ($1.type);
 611                           write_exp_elt_opcode (UNOP_CAST);
 612                         }
 613                 ;
 614
 615 /* Z.200, 5.2.12 */
 616
 617 value_procedure_call:   FIXME_05
 618                         {
 619                           $$ = 0;       /* FIXME */
 620                         }
 621                 ;
 622
 623 /* Z.200, 5.2.13 */
 624
 625 value_built_in_routine_call:    chill_value_built_in_routine_call
 626                         {
 627                           $$ = 0;       /* FIXME */
 628                         }
 629                 ;
 630
 631 /* Z.200, 5.2.14 */
 632
 633 start_expression:       FIXME_06
 634                         {
 635                           $$ = 0;       /* FIXME */
 636                         }       /* Not in GNU-Chill */
 637                 ;
 638
 639 /* Z.200, 5.2.15 */
 640
 641 zero_adic_operator:     FIXME_07
 642                         {
 643                           $$ = 0;       /* FIXME */
 644                         }
 645                 ;
 646
 647 /* Z.200, 5.2.16 */
 648
 649 parenthesised_expression:       '(' expression ')'
 650                         {
 651                           $$ = 0;       /* FIXME */
 652                         }
 653                 ;
 654
 655 /* Z.200, 5.3.2 */
 656
 657 expression      :       operand_0
 658                         {
 659                           $$ = 0;       /* FIXME */
 660                         }
 661                 |       single_assignment_action
 662                         {
 663                           $$ = 0;       /* FIXME */
 664                         }
 665                 |       conditional_expression
 666                         {
 667                           $$ = 0;       /* FIXME */
 668                         }
 669                 ;
 670
 671 conditional_expression : IF boolean_expression then_alternative else_alternative FI
 672                         {
 673                           $$ = 0;       /* FIXME */
 674                         }
 675                 |       CASE case_selector_list OF value_case_alternative '[' ELSE sub_expression ']' ESAC
 676                         {
 677                           $$ = 0;       /* FIXME */
 678                         }
 679                 ;
 680
 681 then_alternative:       THEN subexpression
 682                         {
 683                           $$ = 0;       /* FIXME */
 684                         }
 685                 ;
 686
 687 else_alternative:       ELSE subexpression
 688                         {
 689                           $$ = 0;       /* FIXME */
 690                         }
 691                 |       ELSIF boolean_expression then_alternative else_alternative
 692                         {
 693                           $$ = 0;       /* FIXME */
 694                         }
 695                 ;
 696
 697 sub_expression  :       expression
 698                         {
 699                           $$ = 0;       /* FIXME */
 700                         }
 701                 ;
 702
 703 value_case_alternative: case_label_specification ':' sub_expression ';'
 704                         {
 705                           $$ = 0;       /* FIXME */
 706                         }
 707                 ;
 708
 709 /* Z.200, 5.3.3 */
 710
 711 operand_0       :       operand_1
 712                         {
 713                           $$ = 0;       /* FIXME */
 714                         }
 715                 |       operand_0 LOGIOR operand_1
 716                         {
 717                           write_exp_elt_opcode (BINOP_BITWISE_IOR);
 718                         }
 719                 |       operand_0 ORIF operand_1
 720                         {
 721                           $$ = 0;       /* FIXME */
 722                         }
 723                 |       operand_0 LOGXOR operand_1
 724                         {
 725                           write_exp_elt_opcode (BINOP_BITWISE_XOR);
 726                         }
 727                 ;
 728
 729 /* Z.200, 5.3.4 */
 730
 731 operand_1       :       operand_2
 732                         {
 733                           $$ = 0;       /* FIXME */
 734                         }
 735                 |       operand_1 LOGAND operand_2
 736                         {
 737                           write_exp_elt_opcode (BINOP_BITWISE_AND);
 738                         }
 739                 |       operand_1 ANDIF operand_2
 740                         {
 741                           $$ = 0;       /* FIXME */
 742                         }
 743                 ;
 744
 745 /* Z.200, 5.3.5 */
 746
 747 operand_2       :       operand_3
 748                         {
 749                           $$ = 0;       /* FIXME */
 750                         }
 751                 |       operand_2 '=' operand_3
 752                         {
 753                           write_exp_elt_opcode (BINOP_EQUAL);
 754                         }
 755                 |       operand_2 NOTEQUAL operand_3
 756                         {
 757                           write_exp_elt_opcode (BINOP_NOTEQUAL);
 758                         }
 759                 |       operand_2 '>' operand_3
 760                         {
 761                           write_exp_elt_opcode (BINOP_GTR);
 762                         }
 763                 |       operand_2 GTR operand_3
 764                         {
 765                           write_exp_elt_opcode (BINOP_GEQ);
 766                         }
 767                 |       operand_2 '<' operand_3
 768                         {
 769                           write_exp_elt_opcode (BINOP_LESS);
 770                         }
 771                 |       operand_2 LEQ operand_3
 772                         {
 773                           write_exp_elt_opcode (BINOP_LEQ);
 774                         }
 775                 |       operand_2 IN operand_3
 776                         {
 777                           write_exp_elt_opcode (BINOP_IN);
 778                         }
 779                 ;
 780
 781
 782 /* Z.200, 5.3.6 */
 783
 784 operand_3       :       operand_4
 785                         {
 786                           $$ = 0;       /* FIXME */
 787                         }
 788                 |       operand_3 '+' operand_4
 789                         {
 790                           write_exp_elt_opcode (BINOP_ADD);
 791                         }
 792                 |       operand_3 '-' operand_4
 793                         {
 794                           write_exp_elt_opcode (BINOP_SUB);
 795                         }
 796                 |       operand_3 SLASH_SLASH operand_4
 797                         {
 798                           write_exp_elt_opcode (BINOP_CONCAT);
 799                         }
 800                 ;
 801
 802 /* Z.200, 5.3.7 */
 803
 804 operand_4       :       operand_5
 805                         {
 806                           $$ = 0;       /* FIXME */
 807                         }
 808                 |       operand_4 '*' operand_5
 809                         {
 810                           write_exp_elt_opcode (BINOP_MUL);
 811                         }
 812                 |       operand_4 '/' operand_5
 813                         {
 814                           write_exp_elt_opcode (BINOP_DIV);
 815                         }
 816                 |       operand_4 MOD operand_5
 817                         {
 818                           write_exp_elt_opcode (BINOP_MOD);
 819                         }
 820                 |       operand_4 REM operand_5
 821                         {
 822                           write_exp_elt_opcode (BINOP_REM);
 823                         }
 824                 ;
 825
 826 /* Z.200, 5.3.8 */
 827
 828 operand_5       :       operand_6
 829                         {
 830                           $$ = 0;       /* FIXME */
 831                         }
 832                 |       '-' operand_6
 833                         {
 834                           write_exp_elt_opcode (UNOP_NEG);
 835                         }
 836                 |       NOT operand_6
 837                         {
 838                           write_exp_elt_opcode (UNOP_LOGICAL_NOT);
 839                         }
 840                 |       parenthesised_expression literal
 841 /* We require the string operand to be a literal, to avoid some
 842    nasty parsing ambiguities. */
 843                         {
 844                           write_exp_elt_opcode (BINOP_CONCAT);
 845                         }
 846                 ;
 847
 848 /* Z.200, 5.3.9 */
 849
 850 operand_6       :       POINTER location
 851                         {
 852                           write_exp_elt_opcode (UNOP_ADDR);
 853                         }
 854                 |       RECEIVE buffer_location
 855                         {
 856                           $$ = 0;       /* FIXME */
 857                         }
 858                 |       primitive_value
 859                         {
 860                           $$ = 0;       /* FIXME */
 861                         }
 862                 ;
 863
 864
 865 /* Z.200, 6.2 */
 866
 867 single_assignment_action :
 868                         location GDB_ASSIGNMENT value
 869                         {
 870                           write_exp_elt_opcode (BINOP_ASSIGN);
 871                         }
 872                 ;
 873
 874 /* Z.200, 6.20.3 */
 875
 876 chill_value_built_in_routine_call :
 877                         NUM '(' expression ')'
 878                         {
 879                           $$ = 0;       /* FIXME */
 880                         }
 881                 |       PRED '(' expression ')'
 882                         {
 883                           $$ = 0;       /* FIXME */
 884                         }
 885                 |       SUCC '(' expression ')'
 886                         {
 887                           $$ = 0;       /* FIXME */
 888                         }
 889                 |       ABS '(' expression ')'
 890                         {
 891                           $$ = 0;       /* FIXME */
 892                         }
 893                 |       CARD '(' expression ')'
 894                         {
 895                           $$ = 0;       /* FIXME */
 896                         }
 897                 |       MAX_TOKEN '(' expression ')'
 898                         {
 899                           $$ = 0;       /* FIXME */
 900                         }
 901                 |       MIN_TOKEN '(' expression ')'
 902                         {
 903                           $$ = 0;       /* FIXME */
 904                         }
 905                 |       SIZE '(' location ')'
 906                         {
 907                           $$ = 0;       /* FIXME */
 908                         }
 909                 |       SIZE '(' mode_argument ')'
 910                         {
 911                           $$ = 0;       /* FIXME */
 912                         }
 913                 |       UPPER '(' upper_lower_argument ')'
 914                         {
 915                           $$ = 0;       /* FIXME */
 916                         }
 917                 |       LOWER '(' upper_lower_argument ')'
 918                         {
 919                           $$ = 0;       /* FIXME */
 920                         }
 921                 |       LENGTH '(' length_argument ')'
 922                         {
 923                           $$ = 0;       /* FIXME */
 924                         }
 925                 ;
 926
 927 mode_argument :         mode_name
 928                         {
 929                           $$ = 0;       /* FIXME */
 930                         }
 931                 |       array_mode_name '(' expression ')'
 932                         {
 933                           $$ = 0;       /* FIXME */
 934                         }
 935                 |       string_mode_name '(' expression ')'
 936                         {
 937                           $$ = 0;       /* FIXME */
 938                         }
 939                 |       variant_structure_mode_name '(' expression_list ')'
 940                         {
 941                           $$ = 0;       /* FIXME */
 942                         }
 943                 ;
 944
 945 mode_name :             TYPENAME
 946                 ;
 947
 948 upper_lower_argument :  expression
 949                         {
 950                           $$ = 0;       /* FIXME */
 951                         }
 952                 |       mode_name
 953                         {
 954                           $$ = 0;       /* FIXME */
 955                         }
 956                 ;
 957
 958 length_argument :       expression
 959                         {
 960                           $$ = 0;       /* FIXME */
 961                         }
 962                 ;
 963
 964 /* Z.200, 12.4.3 */
 965
 966 array_primitive_value : primitive_value
 967                         {
 968                           $$ = 0;
 969                         }
 970                 ;
 971
 972
 973 /* Things which still need productions... */
 974
 975 array_mode_name         :       FIXME_08 { $$ = 0; }
 976 string_mode_name        :       FIXME_09 { $$ = 0; }
 977 variant_structure_mode_name:    FIXME_10 { $$ = 0; }
 978 synonym_name            :       FIXME_11 { $$ = 0; }
 979 value_enumeration_name  :       FIXME_12 { $$ = 0; }
 980 value_do_with_name      :       FIXME_13 { $$ = 0; }
 981 value_receive_name      :       FIXME_14 { $$ = 0; }
 982 string_primitive_value  :       FIXME_15 { $$ = 0; }
 983 start_element           :       FIXME_16 { $$ = 0; }
 984 left_element            :       FIXME_17 { $$ = 0; }
 985 right_element           :       FIXME_18 { $$ = 0; }
 986 slice_size              :       FIXME_19 { $$ = 0; }
 987 lower_element           :       FIXME_20 { $$ = 0; }
 988 upper_element           :       FIXME_21 { $$ = 0; }
 989 first_element           :       FIXME_22 { $$ = 0; }
 990 boolean_expression      :       FIXME_26 { $$ = 0; }
 991 case_selector_list      :       FIXME_27 { $$ = 0; }
 992 subexpression           :       FIXME_28 { $$ = 0; }
 993 case_label_specification:       FIXME_29 { $$ = 0; }
 994 buffer_location         :       FIXME_30 { $$ = 0; }
 995
 996 %%
 997
 998 /* Implementation of a dynamically expandable buffer for processing input
 999    characters acquired through lexptr and building a value to return in
1000    yylval. */
1001
1002 static char *tempbuf;           /* Current buffer contents */
1003 static int tempbufsize;         /* Size of allocated buffer */
1004 static int tempbufindex;        /* Current index into buffer */
1005
1006 #define GROWBY_MIN_SIZE 64      /* Minimum amount to grow buffer by */
1007
1008 #define CHECKBUF(size) \
1009   do { \
1010     if (tempbufindex + (size) >= tempbufsize) \
1011       { \
1012         growbuf_by_size (size); \
1013       } \
1014   } while (0);
1015
1016 /* Grow the static temp buffer if necessary, including allocating the first one
1017    on demand. */
1018
1019 static void
1020 growbuf_by_size (count)
1021      int count;
1022 {
1023   int growby;
1024
1025   growby = max (count, GROWBY_MIN_SIZE);
1026   tempbufsize += growby;
1027   if (tempbuf == NULL)
1028     {
1029       tempbuf = (char *) malloc (tempbufsize);
1030     }
1031   else
1032     {
1033       tempbuf = (char *) realloc (tempbuf, tempbufsize);
1034     }
1035 }
1036
1037 /* Try to consume a simple name string token.  If successful, returns
1038    a pointer to a nullbyte terminated copy of the name that can be used
1039    in symbol table lookups.  If not successful, returns NULL. */
1040
1041 static char *
1042 match_simple_name_string ()
1043 {
1044   char *tokptr = lexptr;
1045
1046   if (isalpha (*tokptr))
1047     {
1048       char *result;
1049       do {
1050         tokptr++;
1051       } while (isalnum (*tokptr) || (*tokptr == '_'));
1052       yylval.sval.ptr = lexptr;
1053       yylval.sval.length = tokptr - lexptr;
1054       lexptr = tokptr;
1055       result = copy_name (yylval.sval);
1056       for (tokptr = result; *tokptr; tokptr++)
1057         if (isupper (*tokptr))
1058           *tokptr = tolower(*tokptr);
1059       return result;
1060     }
1061   return (NULL);
1062 }
1063
1064 /* Start looking for a value composed of valid digits as set by the base
1065    in use.  Note that '_' characters are valid anywhere, in any quantity,
1066    and are simply ignored.  Since we must find at least one valid digit,
1067    or reject this token as an integer literal, we keep track of how many
1068    digits we have encountered. */
1069
1070 static int
1071 decode_integer_value (base, tokptrptr, ivalptr)
1072   int base;
1073   char **tokptrptr;
1074   int *ivalptr;
1075 {
1076   char *tokptr = *tokptrptr;
1077   int temp;
1078   int digits = 0;
1079
1080   while (*tokptr != '\0')
1081     {
1082       temp = tolower (*tokptr);
1083       tokptr++;
1084       switch (temp)
1085         {
1086         case '_':
1087           continue;
1088         case '0':  case '1':  case '2':  case '3':  case '4':
1089         case '5':  case '6':  case '7':  case '8':  case '9':
1090           temp -= '0';
1091           break;
1092         case 'a':  case 'b':  case 'c':  case 'd':  case 'e': case 'f':
1093           temp -= 'a';
1094           temp += 10;
1095           break;
1096         default:
1097           temp = base;
1098           break;
1099         }
1100       if (temp < base)
1101         {
1102           digits++;
1103           *ivalptr *= base;
1104           *ivalptr += temp;
1105         }
1106       else
1107         {
1108           /* Found something not in domain for current base. */
1109           tokptr--;     /* Unconsume what gave us indigestion. */
1110           break;
1111         }
1112     }
1113
1114   /* If we didn't find any digits, then we don't have a valid integer
1115      value, so reject the entire token.  Otherwise, update the lexical
1116      scan pointer, and return non-zero for success. */
1117
1118   if (digits == 0)
1119     {
1120       return (0);
1121     }
1122   else
1123     {
1124       *tokptrptr = tokptr;
1125       return (1);
1126     }
1127 }
1128
1129 static int
1130 decode_integer_literal (valptr, tokptrptr)
1131   int *valptr;
1132   char **tokptrptr;
1133 {
1134   char *tokptr = *tokptrptr;
1135   int base = 0;
1136   int ival = 0;
1137   int explicit_base = 0;
1138
1139   /* Look for an explicit base specifier, which is optional. */
1140
1141   switch (*tokptr)
1142     {
1143     case 'd':
1144     case 'D':
1145       explicit_base++;
1146       base = 10;
1147       tokptr++;
1148       break;
1149     case 'b':
1150     case 'B':
1151       explicit_base++;
1152       base = 2;
1153       tokptr++;
1154       break;
1155     case 'h':
1156     case 'H':
1157       explicit_base++;
1158       base = 16;
1159       tokptr++;
1160       break;
1161     case 'o':
1162     case 'O':
1163       explicit_base++;
1164       base = 8;
1165       tokptr++;
1166       break;
1167     default:
1168       base = 10;
1169       break;
1170     }
1171
1172   /* If we found an explicit base ensure that the character after the
1173      explicit base is a single quote. */
1174
1175   if (explicit_base && (*tokptr++ != '\''))
1176     {
1177       return (0);
1178     }
1179
1180   /* Attempt to decode whatever follows as an integer value in the
1181      indicated base, updating the token pointer in the process and
1182      computing the value into ival.  Also, if we have an explicit
1183      base, then the next character must not be a single quote, or we
1184      have a bitstring literal, so reject the entire token in this case.
1185      Otherwise, update the lexical scan pointer, and return non-zero
1186      for success. */
1187
1188   if (!decode_integer_value (base, &tokptr, &ival))
1189     {
1190       return (0);
1191     }
1192   else if (explicit_base && (*tokptr == '\''))
1193     {
1194       return (0);
1195     }
1196   else
1197     {
1198       *valptr = ival;
1199       *tokptrptr = tokptr;
1200       return (1);
1201     }
1202 }
1203
1204 /*  If it wasn't for the fact that floating point values can contain '_'
1205     characters, we could just let strtod do all the hard work by letting it
1206     try to consume as much of the current token buffer as possible and
1207     find a legal conversion.  Unfortunately we need to filter out the '_'
1208     characters before calling strtod, which we do by copying the other
1209     legal chars to a local buffer to be converted.  However since we also
1210     need to keep track of where the last unconsumed character in the input
1211     buffer is, we have transfer only as many characters as may compose a
1212     legal floating point value. */
1213
1214 static int
1215 match_float_literal ()
1216 {
1217   char *tokptr = lexptr;
1218   char *buf;
1219   char *copy;
1220   double dval;
1221   extern double strtod ();
1222
1223   /* Make local buffer in which to build the string to convert.  This is
1224      required because underscores are valid in chill floating point numbers
1225      but not in the string passed to strtod to convert.  The string will be
1226      no longer than our input string. */
1227
1228   copy = buf = (char *) alloca (strlen (tokptr) + 1);
1229
1230   /* Transfer all leading digits to the conversion buffer, discarding any
1231      underscores. */
1232
1233   while (isdigit (*tokptr) || *tokptr == '_')
1234     {
1235       if (*tokptr != '_')
1236         {
1237           *copy++ = *tokptr;
1238         }
1239       tokptr++;
1240     }
1241
1242   /* Now accept either a '.', or one of [eEdD].  Dot is legal regardless
1243      of whether we found any leading digits, and we simply accept it and
1244      continue on to look for the fractional part and/or exponent.  One of
1245      [eEdD] is legal only if we have seen digits, and means that there
1246      is no fractional part.  If we find neither of these, then this is
1247      not a floating point number, so return failure. */
1248
1249   switch (*tokptr++)
1250     {
1251       case '.':
1252         /* Accept and then look for fractional part and/or exponent. */
1253         *copy++ = '.';
1254         break;
1255
1256       case 'e':
1257       case 'E':
1258       case 'd':
1259       case 'D':
1260         if (copy == buf)
1261           {
1262             return (0);
1263           }
1264         *copy++ = 'e';
1265         goto collect_exponent;
1266         break;
1267
1268       default:
1269         return (0);
1270         break;
1271     }
1272
1273   /* We found a '.', copy any fractional digits to the conversion buffer, up
1274      to the first nondigit, non-underscore character. */
1275
1276   while (isdigit (*tokptr) || *tokptr == '_')
1277     {
1278       if (*tokptr != '_')
1279         {
1280           *copy++ = *tokptr;
1281         }
1282       tokptr++;
1283     }
1284
1285   /* Look for an exponent, which must start with one of [eEdD].  If none
1286      is found, jump directly to trying to convert what we have collected
1287      so far. */
1288
1289   switch (*tokptr)
1290     {
1291       case 'e':
1292       case 'E':
1293       case 'd':
1294       case 'D':
1295         *copy++ = 'e';
1296         tokptr++;
1297         break;
1298       default:
1299         goto convert_float;
1300         break;
1301     }
1302
1303   /* Accept an optional '-' or '+' following one of [eEdD]. */
1304
1305   collect_exponent:
1306   if (*tokptr == '+' || *tokptr == '-')
1307     {
1308       *copy++ = *tokptr++;
1309     }
1310
1311   /* Now copy an exponent into the conversion buffer.  Note that at the
1312      moment underscores are *not* allowed in exponents. */
1313
1314   while (isdigit (*tokptr))
1315     {
1316       *copy++ = *tokptr++;
1317     }
1318
1319   /* If we transfered any chars to the conversion buffer, try to interpret its
1320      contents as a floating point value.  If any characters remain, then we
1321      must not have a valid floating point string. */
1322
1323   convert_float:
1324   *copy = '\0';
1325   if (copy != buf)
1326       {
1327         dval = strtod (buf, &copy);
1328         if (*copy == '\0')
1329           {
1330             yylval.dval = dval;
1331             lexptr = tokptr;
1332             return (FLOAT_LITERAL);
1333           }
1334       }
1335   return (0);
1336 }
1337
1338 /* Recognize a string literal.  A string literal is a sequence
1339    of characters enclosed in matching single or double quotes, except that
1340    a single character inside single quotes is a character literal, which
1341    we reject as a string literal.  To embed the terminator character inside
1342    a string, it is simply doubled (I.E. "this""is""one""string") */
1343
1344 static int
1345 match_string_literal ()
1346 {
1347   char *tokptr = lexptr;
1348
1349   for (tempbufindex = 0, tokptr++; *tokptr != '\0'; tokptr++)
1350     {
1351       CHECKBUF (1);
1352       if (*tokptr == *lexptr)
1353         {
1354           if (*(tokptr + 1) == *lexptr)
1355             {
1356               tokptr++;
1357             }
1358           else
1359             {
1360               break;
1361             }
1362         }
1363       tempbuf[tempbufindex++] = *tokptr;
1364     }
1365   if (*tokptr == '\0'                                   /* no terminator */
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;
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_TOKEN },
1746     { "min", MIN_TOKEN },
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
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     if (simplename != NULL)
1890       {
1891         /* See if it is a reserved identifier. */
1892         for (i = 0; i < sizeof (idtokentab) / sizeof (idtokentab[0]); i++)
1893             {
1894                 if (STREQ (simplename, idtokentab[i].operator))
1895                     {
1896                         return (idtokentab[i].token);
1897                     }
1898             }
1899
1900         /* Look for other special tokens. */
1901         if (STREQ (simplename, "true"))
1902             {
1903                 yylval.ulval = 1;
1904                 return (BOOLEAN_LITERAL);
1905             }
1906         if (STREQ (simplename, "false"))
1907             {
1908                 yylval.ulval = 0;
1909                 return (BOOLEAN_LITERAL);
1910             }
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_REGPARM_ADDR:
1934               case LOC_LOCAL:
1935               case LOC_LOCAL_ARG:
1936               case LOC_BASEREG:
1937               case LOC_BASEREG_ARG:
1938                 if (innermost_block == NULL
1939                     || contained_in (block_found, innermost_block))
1940                   {
1941                     innermost_block = block_found;
1942                   }
1943                 return (LOCATION_NAME);
1944                 break;
1945               case LOC_CONST:
1946               case LOC_LABEL:
1947                 return (LOCATION_NAME);
1948                 break;
1949               case LOC_TYPEDEF:
1950                 yylval.tsym.type = SYMBOL_TYPE (sym);
1951                 return TYPENAME;
1952               case LOC_UNDEF:
1953               case LOC_CONST_BYTES:
1954               case LOC_OPTIMIZED_OUT:
1955                 error ("Symbol \"%s\" names no location.", simplename);
1956                 break;
1957               }
1958           }
1959         else if (!have_full_symbols () && !have_partial_symbols ())
1960           {
1961             error ("No symbol table is loaded.  Use the \"file\" command.");
1962           }
1963         else
1964           {
1965             error ("No symbol \"%s\" in current context.", simplename);
1966           }
1967       }
1968
1969     /* Catch single character tokens which are not part of some
1970        longer token. */
1971
1972     switch (*lexptr)
1973       {
1974         case '.':                       /* Not float for example. */
1975           lexptr++;
1976           while (isspace (*lexptr)) lexptr++;
1977           simplename = match_simple_name_string ();
1978           if (!simplename)
1979             return '.';
1980           return FIELD_NAME;
1981       }
1982
1983     return (ILLEGAL_TOKEN);
1984 }
1985
1986 void
1987 yyerror (msg)
1988      char *msg; /* unused */
1989 {
1990   printf_unfiltered ("Parsing:  %s\n", lexptr);
1991   if (yychar < 256)
1992     {
1993       error ("Invalid syntax in expression near character '%c'.", yychar);
1994     }
1995   else
1996     {
1997       error ("Invalid syntax in expression");
1998     }
1999 }