gdb/ch-exp.y

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