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                           $$ = 0;       /* FIXME */
 510                         }
 511                 |       EMPTINESS_LITERAL
 512                         {
 513                           $$ = 0;       /* FIXME */
 514                         }
 515                 |       CHARACTER_STRING_LITERAL
 516                         {
 517                           write_exp_elt_opcode (OP_STRING);
 518                           write_exp_string ($1);
 519                           write_exp_elt_opcode (OP_STRING);
 520                         }
 521                 |       BIT_STRING_LITERAL
 522                         {
 523                           write_exp_elt_opcode (OP_BITSTRING);
 524                           write_exp_bitstring ($1);
 525                           write_exp_elt_opcode (OP_BITSTRING);
 526                         }
 527                 ;
 528
 529 /* Z.200, 5.2.5 */
 530
 531 tuple           :       FIXME_04
 532                         {
 533                           $$ = 0;       /* FIXME */
 534                         }
 535                 ;
 536
 537
 538 /* Z.200, 5.2.6 */
 539
 540 value_string_element:   string_primitive_value '(' start_element ')'
 541                         {
 542                           $$ = 0;       /* FIXME */
 543                         }
 544                 ;
 545
 546 /* Z.200, 5.2.7 */
 547
 548 value_string_slice:     string_primitive_value '(' left_element ':' right_element ')'
 549                         {
 550                           $$ = 0;       /* FIXME */
 551                         }
 552                 |       string_primitive_value '(' start_element UP slice_size ')'
 553                         {
 554                           $$ = 0;       /* FIXME */
 555                         }
 556                 ;
 557
 558 /* Z.200, 5.2.9 */
 559
 560 value_array_slice:      primitive_value '(' lower_element ':' upper_element ')'
 561                         {
 562                           $$ = 0;       /* FIXME */
 563                         }
 564                 |       primitive_value '(' first_element UP slice_size ')'
 565                         {
 566                           $$ = 0;       /* FIXME */
 567                         }
 568                 ;
 569
 570 /* Z.200, 5.2.11 */
 571
 572 expression_conversion:  mode_name parenthesised_expression
 573                         {
 574                           write_exp_elt_opcode (UNOP_CAST);
 575                           write_exp_elt_type ($1.type);
 576                           write_exp_elt_opcode (UNOP_CAST);
 577                         }
 578                 ;
 579
 580 /* Z.200, 5.2.12 */
 581
 582 value_procedure_call:   FIXME_05
 583                         {
 584                           $$ = 0;       /* FIXME */
 585                         }
 586                 ;
 587
 588 /* Z.200, 5.2.13 */
 589
 590 value_built_in_routine_call:    chill_value_built_in_routine_call
 591                         {
 592                           $$ = 0;       /* FIXME */
 593                         }
 594                 ;
 595
 596 /* Z.200, 5.2.14 */
 597
 598 start_expression:       FIXME_06
 599                         {
 600                           $$ = 0;       /* FIXME */
 601                         }       /* Not in GNU-Chill */
 602                 ;
 603
 604 /* Z.200, 5.2.15 */
 605
 606 zero_adic_operator:     FIXME_07
 607                         {
 608                           $$ = 0;       /* FIXME */
 609                         }
 610                 ;
 611
 612 /* Z.200, 5.2.16 */
 613
 614 parenthesised_expression:       '(' expression ')'
 615                         {
 616                           $$ = 0;       /* FIXME */
 617                         }
 618                 ;
 619
 620 /* Z.200, 5.3.2 */
 621
 622 expression      :       operand_0
 623                         {
 624                           $$ = 0;       /* FIXME */
 625                         }
 626                 |       single_assignment_action
 627                         {
 628                           $$ = 0;       /* FIXME */
 629                         }
 630                 |       conditional_expression
 631                         {
 632                           $$ = 0;       /* FIXME */
 633                         }
 634                 ;
 635
 636 conditional_expression : IF boolean_expression then_alternative else_alternative FI
 637                         {
 638                           $$ = 0;       /* FIXME */
 639                         }
 640                 |       CASE case_selector_list OF value_case_alternative '[' ELSE sub_expression ']' ESAC
 641                         {
 642                           $$ = 0;       /* FIXME */
 643                         }
 644                 ;
 645
 646 then_alternative:       THEN subexpression
 647                         {
 648                           $$ = 0;       /* FIXME */
 649                         }
 650                 ;
 651
 652 else_alternative:       ELSE subexpression
 653                         {
 654                           $$ = 0;       /* FIXME */
 655                         }
 656                 |       ELSIF boolean_expression then_alternative else_alternative
 657                         {
 658                           $$ = 0;       /* FIXME */
 659                         }
 660                 ;
 661
 662 sub_expression  :       expression
 663                         {
 664                           $$ = 0;       /* FIXME */
 665                         }
 666                 ;
 667
 668 value_case_alternative: case_label_specification ':' sub_expression ';'
 669                         {
 670                           $$ = 0;       /* FIXME */
 671                         }
 672                 ;
 673
 674 /* Z.200, 5.3.3 */
 675
 676 operand_0       :       operand_1
 677                         {
 678                           $$ = 0;       /* FIXME */
 679                         }
 680                 |       operand_0 LOGIOR operand_1
 681                         {
 682                           write_exp_elt_opcode (BINOP_BITWISE_IOR);
 683                         }
 684                 |       operand_0 ORIF operand_1
 685                         {
 686                           $$ = 0;       /* FIXME */
 687                         }
 688                 |       operand_0 LOGXOR operand_1
 689                         {
 690                           write_exp_elt_opcode (BINOP_BITWISE_XOR);
 691                         }
 692                 ;
 693
 694 /* Z.200, 5.3.4 */
 695
 696 operand_1       :       operand_2
 697                         {
 698                           $$ = 0;       /* FIXME */
 699                         }
 700                 |       operand_1 LOGAND operand_2
 701                         {
 702                           write_exp_elt_opcode (BINOP_BITWISE_AND);
 703                         }
 704                 |       operand_1 ANDIF operand_2
 705                         {
 706                           $$ = 0;       /* FIXME */
 707                         }
 708                 ;
 709
 710 /* Z.200, 5.3.5 */
 711
 712 operand_2       :       operand_3
 713                         {
 714                           $$ = 0;       /* FIXME */
 715                         }
 716                 |       operand_2 '=' operand_3
 717                         {
 718                           write_exp_elt_opcode (BINOP_EQUAL);
 719                         }
 720                 |       operand_2 NOTEQUAL operand_3
 721                         {
 722                           write_exp_elt_opcode (BINOP_NOTEQUAL);
 723                         }
 724                 |       operand_2 '>' operand_3
 725                         {
 726                           write_exp_elt_opcode (BINOP_GTR);
 727                         }
 728                 |       operand_2 GTR operand_3
 729                         {
 730                           write_exp_elt_opcode (BINOP_GEQ);
 731                         }
 732                 |       operand_2 '<' operand_3
 733                         {
 734                           write_exp_elt_opcode (BINOP_LESS);
 735                         }
 736                 |       operand_2 LEQ operand_3
 737                         {
 738                           write_exp_elt_opcode (BINOP_LEQ);
 739                         }
 740                 |       operand_2 IN operand_3
 741                         {
 742                           write_exp_elt_opcode (BINOP_IN);
 743                         }
 744                 ;
 745
 746
 747 /* Z.200, 5.3.6 */
 748
 749 operand_3       :       operand_4
 750                         {
 751                           $$ = 0;       /* FIXME */
 752                         }
 753                 |       operand_3 '+' operand_4
 754                         {
 755                           write_exp_elt_opcode (BINOP_ADD);
 756                         }
 757                 |       operand_3 '-' operand_4
 758                         {
 759                           write_exp_elt_opcode (BINOP_SUB);
 760                         }
 761                 |       operand_3 SLASH_SLASH operand_4
 762                         {
 763                           write_exp_elt_opcode (BINOP_CONCAT);
 764                         }
 765                 ;
 766
 767 /* Z.200, 5.3.7 */
 768
 769 operand_4       :       operand_5
 770                         {
 771                           $$ = 0;       /* FIXME */
 772                         }
 773                 |       operand_4 '*' operand_5
 774                         {
 775                           write_exp_elt_opcode (BINOP_MUL);
 776                         }
 777                 |       operand_4 '/' operand_5
 778                         {
 779                           write_exp_elt_opcode (BINOP_DIV);
 780                         }
 781                 |       operand_4 MOD operand_5
 782                         {
 783                           write_exp_elt_opcode (BINOP_MOD);
 784                         }
 785                 |       operand_4 REM operand_5
 786                         {
 787                           write_exp_elt_opcode (BINOP_REM);
 788                         }
 789                 ;
 790
 791 /* Z.200, 5.3.8 */
 792
 793 operand_5       :       operand_6
 794                         {
 795                           $$ = 0;       /* FIXME */
 796                         }
 797                 |       '-' operand_6
 798                         {
 799                           write_exp_elt_opcode (UNOP_NEG);
 800                         }
 801                 |       NOT operand_6
 802                         {
 803                           write_exp_elt_opcode (UNOP_LOGICAL_NOT);
 804                         }
 805                 |       parenthesised_expression literal
 806 /* We require the string operand to be a literal, to avoid some
 807    nasty parsing ambiguities. */
 808                         {
 809                           write_exp_elt_opcode (BINOP_CONCAT);
 810                         }
 811                 ;
 812
 813 /* Z.200, 5.3.9 */
 814
 815 operand_6       :       POINTER primitive_value
 816                         {
 817                           write_exp_elt_opcode (UNOP_ADDR);
 818                         }
 819                 |       RECEIVE buffer_location
 820                         {
 821                           $$ = 0;       /* FIXME */
 822                         }
 823                 |       primitive_value
 824                         {
 825                           $$ = 0;       /* FIXME */
 826                         }
 827                 ;
 828
 829
 830 /* Z.200, 6.2 */
 831
 832 single_assignment_action :
 833                         primitive_value GDB_ASSIGNMENT value
 834                         {
 835                           write_exp_elt_opcode (BINOP_ASSIGN);
 836                         }
 837                 ;
 838
 839 /* Z.200, 6.20.3 */
 840
 841 chill_value_built_in_routine_call :
 842                         NUM '(' expression ')'
 843                         {
 844                           $$ = 0;       /* FIXME */
 845                         }
 846                 |       PRED '(' expression ')'
 847                         {
 848                           $$ = 0;       /* FIXME */
 849                         }
 850                 |       SUCC '(' expression ')'
 851                         {
 852                           $$ = 0;       /* FIXME */
 853                         }
 854                 |       ABS '(' expression ')'
 855                         {
 856                           $$ = 0;       /* FIXME */
 857                         }
 858                 |       CARD '(' expression ')'
 859                         {
 860                           $$ = 0;       /* FIXME */
 861                         }
 862                 |       MAX_TOKEN '(' expression ')'
 863                         {
 864                           $$ = 0;       /* FIXME */
 865                         }
 866                 |       MIN_TOKEN '(' expression ')'
 867                         {
 868                           $$ = 0;       /* FIXME */
 869                         }
 870                 |       SIZE '(' expression ')'
 871                         { write_exp_elt_opcode (UNOP_SIZEOF); }
 872                 |       SIZE '(' mode_argument ')'
 873                         { write_exp_elt_opcode (OP_LONG);
 874                           write_exp_elt_type (builtin_type_int);
 875                           write_exp_elt_longcst ((LONGEST) TYPE_LENGTH ($3));
 876                           write_exp_elt_opcode (OP_LONG); }
 877                 |       UPPER '(' upper_lower_argument ')'
 878                         {
 879                           $$ = 0;       /* FIXME */
 880                         }
 881                 |       LOWER '(' upper_lower_argument ')'
 882                         {
 883                           $$ = 0;       /* FIXME */
 884                         }
 885                 |       LENGTH '(' length_argument ')'
 886                         {
 887                           $$ = 0;       /* FIXME */
 888                         }
 889                 ;
 890
 891 mode_argument :         mode_name
 892                         {
 893                           $$ = $1.type;
 894                         }
 895                 |       array_mode_name '(' expression ')'
 896                         {
 897                           $$ = 0;       /* FIXME */
 898                         }
 899                 |       string_mode_name '(' expression ')'
 900                         {
 901                           $$ = 0;       /* FIXME */
 902                         }
 903                 |       variant_structure_mode_name '(' expression_list ')'
 904                         {
 905                           $$ = 0;       /* FIXME */
 906                         }
 907                 ;
 908
 909 mode_name :             TYPENAME
 910                 ;
 911
 912 upper_lower_argument :  expression
 913                         {
 914                           $$ = 0;       /* FIXME */
 915                         }
 916                 |       mode_name
 917                         {
 918                           $$ = 0;       /* FIXME */
 919                         }
 920                 ;
 921
 922 length_argument :       expression
 923                         {
 924                           $$ = 0;       /* FIXME */
 925                         }
 926                 ;
 927
 928 /* Things which still need productions... */
 929
 930 array_mode_name         :       FIXME_08 { $$ = 0; }
 931 string_mode_name        :       FIXME_09 { $$ = 0; }
 932 variant_structure_mode_name:    FIXME_10 { $$ = 0; }
 933 synonym_name            :       FIXME_11 { $$ = 0; }
 934 value_enumeration_name  :       FIXME_12 { $$ = 0; }
 935 value_do_with_name      :       FIXME_13 { $$ = 0; }
 936 value_receive_name      :       FIXME_14 { $$ = 0; }
 937 string_primitive_value  :       FIXME_15 { $$ = 0; }
 938 start_element           :       FIXME_16 { $$ = 0; }
 939 left_element            :       FIXME_17 { $$ = 0; }
 940 right_element           :       FIXME_18 { $$ = 0; }
 941 slice_size              :       FIXME_19 { $$ = 0; }
 942 lower_element           :       FIXME_20 { $$ = 0; }
 943 upper_element           :       FIXME_21 { $$ = 0; }
 944 first_element           :       FIXME_22 { $$ = 0; }
 945 boolean_expression      :       FIXME_26 { $$ = 0; }
 946 case_selector_list      :       FIXME_27 { $$ = 0; }
 947 subexpression           :       FIXME_28 { $$ = 0; }
 948 case_label_specification:       FIXME_29 { $$ = 0; }
 949 buffer_location         :       FIXME_30 { $$ = 0; }
 950
 951 %%
 952
 953 /* Implementation of a dynamically expandable buffer for processing input
 954    characters acquired through lexptr and building a value to return in
 955    yylval. */
 956
 957 static char *tempbuf;           /* Current buffer contents */
 958 static int tempbufsize;         /* Size of allocated buffer */
 959 static int tempbufindex;        /* Current index into buffer */
 960
 961 #define GROWBY_MIN_SIZE 64      /* Minimum amount to grow buffer by */
 962
 963 #define CHECKBUF(size) \
 964   do { \
 965     if (tempbufindex + (size) >= tempbufsize) \
 966       { \
 967         growbuf_by_size (size); \
 968       } \
 969   } while (0);
 970
 971 /* Grow the static temp buffer if necessary, including allocating the first one
 972    on demand. */
 973
 974 static void
 975 growbuf_by_size (count)
 976      int count;
 977 {
 978   int growby;
 979
 980   growby = max (count, GROWBY_MIN_SIZE);
 981   tempbufsize += growby;
 982   if (tempbuf == NULL)
 983     {
 984       tempbuf = (char *) malloc (tempbufsize);
 985     }
 986   else
 987     {
 988       tempbuf = (char *) realloc (tempbuf, tempbufsize);
 989     }
 990 }
 991
 992 /* Try to consume a simple name string token.  If successful, returns
 993    a pointer to a nullbyte terminated copy of the name that can be used
 994    in symbol table lookups.  If not successful, returns NULL. */
 995
 996 static char *
 997 match_simple_name_string ()
 998 {
 999   char *tokptr = lexptr;
1000
1001   if (isalpha (*tokptr) || *tokptr == '_')
1002     {
1003       char *result;
1004       do {
1005         tokptr++;
1006       } while (isalnum (*tokptr) || (*tokptr == '_'));
1007       yylval.sval.ptr = lexptr;
1008       yylval.sval.length = tokptr - lexptr;
1009       lexptr = tokptr;
1010       result = copy_name (yylval.sval);
1011       return result;
1012     }
1013   return (NULL);
1014 }
1015
1016 /* Start looking for a value composed of valid digits as set by the base
1017    in use.  Note that '_' characters are valid anywhere, in any quantity,
1018    and are simply ignored.  Since we must find at least one valid digit,
1019    or reject this token as an integer literal, we keep track of how many
1020    digits we have encountered. */
1021
1022 static int
1023 decode_integer_value (base, tokptrptr, ivalptr)
1024   int base;
1025   char **tokptrptr;
1026   int *ivalptr;
1027 {
1028   char *tokptr = *tokptrptr;
1029   int temp;
1030   int digits = 0;
1031
1032   while (*tokptr != '\0')
1033     {
1034       temp = *tokptr;
1035       if (isupper (temp))
1036         temp = tolower (temp);
1037       tokptr++;
1038       switch (temp)
1039         {
1040         case '_':
1041           continue;
1042         case '0':  case '1':  case '2':  case '3':  case '4':
1043         case '5':  case '6':  case '7':  case '8':  case '9':
1044           temp -= '0';
1045           break;
1046         case 'a':  case 'b':  case 'c':  case 'd':  case 'e': case 'f':
1047           temp -= 'a';
1048           temp += 10;
1049           break;
1050         default:
1051           temp = base;
1052           break;
1053         }
1054       if (temp < base)
1055         {
1056           digits++;
1057           *ivalptr *= base;
1058           *ivalptr += temp;
1059         }
1060       else
1061         {
1062           /* Found something not in domain for current base. */
1063           tokptr--;     /* Unconsume what gave us indigestion. */
1064           break;
1065         }
1066     }
1067
1068   /* If we didn't find any digits, then we don't have a valid integer
1069      value, so reject the entire token.  Otherwise, update the lexical
1070      scan pointer, and return non-zero for success. */
1071
1072   if (digits == 0)
1073     {
1074       return (0);
1075     }
1076   else
1077     {
1078       *tokptrptr = tokptr;
1079       return (1);
1080     }
1081 }
1082
1083 static int
1084 decode_integer_literal (valptr, tokptrptr)
1085   int *valptr;
1086   char **tokptrptr;
1087 {
1088   char *tokptr = *tokptrptr;
1089   int base = 0;
1090   int ival = 0;
1091   int explicit_base = 0;
1092
1093   /* Look for an explicit base specifier, which is optional. */
1094
1095   switch (*tokptr)
1096     {
1097     case 'd':
1098     case 'D':
1099       explicit_base++;
1100       base = 10;
1101       tokptr++;
1102       break;
1103     case 'b':
1104     case 'B':
1105       explicit_base++;
1106       base = 2;
1107       tokptr++;
1108       break;
1109     case 'h':
1110     case 'H':
1111       explicit_base++;
1112       base = 16;
1113       tokptr++;
1114       break;
1115     case 'o':
1116     case 'O':
1117       explicit_base++;
1118       base = 8;
1119       tokptr++;
1120       break;
1121     default:
1122       base = 10;
1123       break;
1124     }
1125
1126   /* If we found an explicit base ensure that the character after the
1127      explicit base is a single quote. */
1128
1129   if (explicit_base && (*tokptr++ != '\''))
1130     {
1131       return (0);
1132     }
1133
1134   /* Attempt to decode whatever follows as an integer value in the
1135      indicated base, updating the token pointer in the process and
1136      computing the value into ival.  Also, if we have an explicit
1137      base, then the next character must not be a single quote, or we
1138      have a bitstring literal, so reject the entire token in this case.
1139      Otherwise, update the lexical scan pointer, and return non-zero
1140      for success. */
1141
1142   if (!decode_integer_value (base, &tokptr, &ival))
1143     {
1144       return (0);
1145     }
1146   else if (explicit_base && (*tokptr == '\''))
1147     {
1148       return (0);
1149     }
1150   else
1151     {
1152       *valptr = ival;
1153       *tokptrptr = tokptr;
1154       return (1);
1155     }
1156 }
1157
1158 /*  If it wasn't for the fact that floating point values can contain '_'
1159     characters, we could just let strtod do all the hard work by letting it
1160     try to consume as much of the current token buffer as possible and
1161     find a legal conversion.  Unfortunately we need to filter out the '_'
1162     characters before calling strtod, which we do by copying the other
1163     legal chars to a local buffer to be converted.  However since we also
1164     need to keep track of where the last unconsumed character in the input
1165     buffer is, we have transfer only as many characters as may compose a
1166     legal floating point value. */
1167
1168 static int
1169 match_float_literal ()
1170 {
1171   char *tokptr = lexptr;
1172   char *buf;
1173   char *copy;
1174   double dval;
1175   extern double strtod ();
1176
1177   /* Make local buffer in which to build the string to convert.  This is
1178      required because underscores are valid in chill floating point numbers
1179      but not in the string passed to strtod to convert.  The string will be
1180      no longer than our input string. */
1181
1182   copy = buf = (char *) alloca (strlen (tokptr) + 1);
1183
1184   /* Transfer all leading digits to the conversion buffer, discarding any
1185      underscores. */
1186
1187   while (isdigit (*tokptr) || *tokptr == '_')
1188     {
1189       if (*tokptr != '_')
1190         {
1191           *copy++ = *tokptr;
1192         }
1193       tokptr++;
1194     }
1195
1196   /* Now accept either a '.', or one of [eEdD].  Dot is legal regardless
1197      of whether we found any leading digits, and we simply accept it and
1198      continue on to look for the fractional part and/or exponent.  One of
1199      [eEdD] is legal only if we have seen digits, and means that there
1200      is no fractional part.  If we find neither of these, then this is
1201      not a floating point number, so return failure. */
1202
1203   switch (*tokptr++)
1204     {
1205       case '.':
1206         /* Accept and then look for fractional part and/or exponent. */
1207         *copy++ = '.';
1208         break;
1209
1210       case 'e':
1211       case 'E':
1212       case 'd':
1213       case 'D':
1214         if (copy == buf)
1215           {
1216             return (0);
1217           }
1218         *copy++ = 'e';
1219         goto collect_exponent;
1220         break;
1221
1222       default:
1223         return (0);
1224         break;
1225     }
1226
1227   /* We found a '.', copy any fractional digits to the conversion buffer, up
1228      to the first nondigit, non-underscore character. */
1229
1230   while (isdigit (*tokptr) || *tokptr == '_')
1231     {
1232       if (*tokptr != '_')
1233         {
1234           *copy++ = *tokptr;
1235         }
1236       tokptr++;
1237     }
1238
1239   /* Look for an exponent, which must start with one of [eEdD].  If none
1240      is found, jump directly to trying to convert what we have collected
1241      so far. */
1242
1243   switch (*tokptr)
1244     {
1245       case 'e':
1246       case 'E':
1247       case 'd':
1248       case 'D':
1249         *copy++ = 'e';
1250         tokptr++;
1251         break;
1252       default:
1253         goto convert_float;
1254         break;
1255     }
1256
1257   /* Accept an optional '-' or '+' following one of [eEdD]. */
1258
1259   collect_exponent:
1260   if (*tokptr == '+' || *tokptr == '-')
1261     {
1262       *copy++ = *tokptr++;
1263     }
1264
1265   /* Now copy an exponent into the conversion buffer.  Note that at the
1266      moment underscores are *not* allowed in exponents. */
1267
1268   while (isdigit (*tokptr))
1269     {
1270       *copy++ = *tokptr++;
1271     }
1272
1273   /* If we transfered any chars to the conversion buffer, try to interpret its
1274      contents as a floating point value.  If any characters remain, then we
1275      must not have a valid floating point string. */
1276
1277   convert_float:
1278   *copy = '\0';
1279   if (copy != buf)
1280       {
1281         dval = strtod (buf, &copy);
1282         if (*copy == '\0')
1283           {
1284             yylval.dval = dval;
1285             lexptr = tokptr;
1286             return (FLOAT_LITERAL);
1287           }
1288       }
1289   return (0);
1290 }
1291
1292 /* Recognize a string literal.  A string literal is a sequence
1293    of characters enclosed in matching single or double quotes, except that
1294    a single character inside single quotes is a character literal, which
1295    we reject as a string literal.  To embed the terminator character inside
1296    a string, it is simply doubled (I.E. "this""is""one""string") */
1297
1298 static int
1299 match_string_literal ()
1300 {
1301   char *tokptr = lexptr;
1302
1303   for (tempbufindex = 0, tokptr++; *tokptr != '\0'; tokptr++)
1304     {
1305       CHECKBUF (1);
1306       if (*tokptr == *lexptr)
1307         {
1308           if (*(tokptr + 1) == *lexptr)
1309             {
1310               tokptr++;
1311             }
1312           else
1313             {
1314               break;
1315             }
1316         }
1317       tempbuf[tempbufindex++] = *tokptr;
1318     }
1319   if (*tokptr == '\0'                                   /* no terminator */
1320       || (tempbufindex == 1 && *tokptr == '\''))        /* char literal */
1321     {
1322       return (0);
1323     }
1324   else
1325     {
1326       tempbuf[tempbufindex] = '\0';
1327       yylval.sval.ptr = tempbuf;
1328       yylval.sval.length = tempbufindex;
1329       lexptr = ++tokptr;
1330       return (CHARACTER_STRING_LITERAL);
1331     }
1332 }
1333
1334 /* Recognize a character literal.  A character literal is single character
1335    or a control sequence, enclosed in single quotes.  A control sequence
1336    is a comma separated list of one or more integer literals, enclosed
1337    in parenthesis and introduced with a circumflex character.
1338
1339    EX:  'a'  '^(7)'  '^(7,8)'
1340
1341    As a GNU chill extension, the syntax C'xx' is also recognized as a
1342    character literal, where xx is a hex value for the character.
1343
1344    Note that more than a single character, enclosed in single quotes, is
1345    a string literal.
1346
1347    Also note that the control sequence form is not in GNU Chill since it
1348    is ambiguous with the string literal form using single quotes.  I.E.
1349    is '^(7)' a character literal or a string literal.  In theory it it
1350    possible to tell by context, but GNU Chill doesn't accept the control
1351    sequence form, so neither do we (for now the code is disabled).
1352
1353    Returns CHARACTER_LITERAL if a match is found.
1354    */
1355
1356 static int
1357 match_character_literal ()
1358 {
1359   char *tokptr = lexptr;
1360   int ival = 0;
1361
1362   if ((*tokptr == 'c' || *tokptr == 'C') && (*(tokptr + 1) == '\''))
1363     {
1364       /* We have a GNU chill extension form, so skip the leading "C'",
1365          decode the hex value, and then ensure that we have a trailing
1366          single quote character. */
1367       tokptr += 2;
1368       if (!decode_integer_value (16, &tokptr, &ival) || (*tokptr != '\''))
1369         {
1370           return (0);
1371         }
1372       tokptr++;
1373     }
1374   else if (*tokptr == '\'')
1375     {
1376       tokptr++;
1377
1378       /* Determine which form we have, either a control sequence or the
1379          single character form. */
1380
1381       if ((*tokptr == '^') && (*(tokptr + 1) == '('))
1382         {
1383 #if 0     /* Disable, see note above. -fnf */
1384           /* Match and decode a control sequence.  Return zero if we don't
1385              find a valid integer literal, or if the next unconsumed character
1386              after the integer literal is not the trailing ')'.
1387              FIXME:  We currently don't handle the multiple integer literal
1388              form. */
1389           tokptr += 2;
1390           if (!decode_integer_literal (&ival, &tokptr) || (*tokptr++ != ')'))
1391             {
1392               return (0);
1393             }
1394 #else
1395           return (0);
1396 #endif
1397         }
1398       else
1399         {
1400           ival = *tokptr++;
1401         }
1402
1403       /* The trailing quote has not yet been consumed.  If we don't find
1404          it, then we have no match. */
1405
1406       if (*tokptr++ != '\'')
1407         {
1408           return (0);
1409         }
1410     }
1411   else
1412     {
1413       /* Not a character literal. */
1414       return (0);
1415     }
1416   yylval.typed_val.val = ival;
1417   yylval.typed_val.type = builtin_type_chill_char;
1418   lexptr = tokptr;
1419   return (CHARACTER_LITERAL);
1420 }
1421
1422 /* Recognize an integer literal, as specified in Z.200 sec 5.2.4.2.
1423    Note that according to 5.2.4.2, a single "_" is also a valid integer
1424    literal, however GNU-chill requires there to be at least one "digit"
1425    in any integer literal. */
1426
1427 static int
1428 match_integer_literal ()
1429 {
1430   char *tokptr = lexptr;
1431   int ival;
1432
1433   if (!decode_integer_literal (&ival, &tokptr))
1434     {
1435       return (0);
1436     }
1437   else
1438     {
1439       yylval.typed_val.val = ival;
1440       yylval.typed_val.type = builtin_type_int;
1441       lexptr = tokptr;
1442       return (INTEGER_LITERAL);
1443     }
1444 }
1445
1446 /* Recognize a bit-string literal, as specified in Z.200 sec 5.2.4.8
1447    Note that according to 5.2.4.8, a single "_" is also a valid bit-string
1448    literal, however GNU-chill requires there to be at least one "digit"
1449    in any bit-string literal. */
1450
1451 static int
1452 match_bitstring_literal ()
1453 {
1454   char *tokptr = lexptr;
1455   int mask;
1456   int bitoffset = 0;
1457   int bitcount = 0;
1458   int base;
1459   int digit;
1460
1461   tempbufindex = 0;
1462
1463   /* Look for the required explicit base specifier. */
1464
1465   switch (*tokptr++)
1466     {
1467     case 'b':
1468     case 'B':
1469       base = 2;
1470       break;
1471     case 'o':
1472     case 'O':
1473       base = 8;
1474       break;
1475     case 'h':
1476     case 'H':
1477       base = 16;
1478       break;
1479     default:
1480       return (0);
1481       break;
1482     }
1483
1484   /* Ensure that the character after the explicit base is a single quote. */
1485
1486   if (*tokptr++ != '\'')
1487     {
1488       return (0);
1489     }
1490
1491   while (*tokptr != '\0' && *tokptr != '\'')
1492     {
1493       digit = *tokptr;
1494       if (isupper (digit))
1495         digit = tolower (digit);
1496       tokptr++;
1497       switch (digit)
1498         {
1499           case '_':
1500             continue;
1501           case '0':  case '1':  case '2':  case '3':  case '4':
1502           case '5':  case '6':  case '7':  case '8':  case '9':
1503             digit -= '0';
1504             break;
1505           case 'a':  case 'b':  case 'c':  case 'd':  case 'e': case 'f':
1506             digit -= 'a';
1507             digit += 10;
1508             break;
1509           default:
1510             return (0);
1511             break;
1512         }
1513       if (digit >= base)
1514         {
1515           /* Found something not in domain for current base. */
1516           return (0);
1517         }
1518       else
1519         {
1520           /* Extract bits from digit, starting with the msbit appropriate for
1521              the current base, and packing them into the bitstring byte,
1522              starting at the lsbit. */
1523           for (mask = (base >> 1); mask > 0; mask >>= 1)
1524             {
1525               bitcount++;
1526               CHECKBUF (1);
1527               if (digit & mask)
1528                 {
1529                   tempbuf[tempbufindex] |= (1 << bitoffset);
1530                 }
1531               bitoffset++;
1532               if (bitoffset == HOST_CHAR_BIT)
1533                 {
1534                   bitoffset = 0;
1535                   tempbufindex++;
1536                 }
1537             }
1538         }
1539     }
1540
1541   /* Verify that we consumed everything up to the trailing single quote,
1542      and that we found some bits (IE not just underbars). */
1543
1544   if (*tokptr++ != '\'')
1545     {
1546       return (0);
1547     }
1548   else
1549     {
1550       yylval.sval.ptr = tempbuf;
1551       yylval.sval.length = bitcount;
1552       lexptr = tokptr;
1553       return (BIT_STRING_LITERAL);
1554     }
1555 }
1556
1557 /* Recognize tokens that start with '$'.  These include:
1558
1559         $regname        A native register name or a "standard
1560                         register name".
1561                         Return token GDB_REGNAME.
1562
1563         $variable       A convenience variable with a name chosen
1564                         by the user.
1565                         Return token GDB_VARIABLE.
1566
1567         $digits         Value history with index <digits>, starting
1568                         from the first value which has index 1.
1569                         Return GDB_LAST.
1570
1571         $$digits        Value history with index <digits> relative
1572                         to the last value.  I.E. $$0 is the last
1573                         value, $$1 is the one previous to that, $$2
1574                         is the one previous to $$1, etc.
1575                         Return token GDB_LAST.
1576
1577         $ | $0 | $$0    The last value in the value history.
1578                         Return token GDB_LAST.
1579
1580         $$              An abbreviation for the second to the last
1581                         value in the value history, I.E. $$1
1582                         Return token GDB_LAST.
1583
1584     Note that we currently assume that register names and convenience
1585     variables follow the convention of starting with a letter or '_'.
1586
1587    */
1588
1589 static int
1590 match_dollar_tokens ()
1591 {
1592   char *tokptr;
1593   int regno;
1594   int namelength;
1595   int negate;
1596   int ival;
1597
1598   /* We will always have a successful match, even if it is just for
1599      a single '$', the abbreviation for $$0.  So advance lexptr. */
1600
1601   tokptr = ++lexptr;
1602
1603   if (*tokptr == '_' || isalpha (*tokptr))
1604     {
1605       /* Look for a match with a native register name, usually something
1606          like "r0" for example. */
1607
1608       for (regno = 0; regno < NUM_REGS; regno++)
1609         {
1610           namelength = strlen (reg_names[regno]);
1611           if (STREQN (tokptr, reg_names[regno], namelength)
1612               && !isalnum (tokptr[namelength]))
1613             {
1614               yylval.lval = regno;
1615               lexptr += namelength;
1616               return (GDB_REGNAME);
1617             }
1618         }
1619
1620       /* Look for a match with a standard register name, usually something
1621          like "pc", which gdb always recognizes as the program counter
1622          regardless of what the native register name is. */
1623
1624       for (regno = 0; regno < num_std_regs; regno++)
1625         {
1626           namelength = strlen (std_regs[regno].name);
1627           if (STREQN (tokptr, std_regs[regno].name, namelength)
1628               && !isalnum (tokptr[namelength]))
1629             {
1630               yylval.lval = std_regs[regno].regnum;
1631               lexptr += namelength;
1632               return (GDB_REGNAME);
1633             }
1634         }
1635
1636       /* Attempt to match against a convenience variable.  Note that
1637          this will always succeed, because if no variable of that name
1638          already exists, the lookup_internalvar will create one for us.
1639          Also note that both lexptr and tokptr currently point to the
1640          start of the input string we are trying to match, and that we
1641          have already tested the first character for non-numeric, so we
1642          don't have to treat it specially. */
1643
1644       while (*tokptr == '_' || isalnum (*tokptr))
1645         {
1646           tokptr++;
1647         }
1648       yylval.sval.ptr = lexptr;
1649       yylval.sval.length = tokptr - lexptr;
1650       yylval.ivar = lookup_internalvar (copy_name (yylval.sval));
1651       lexptr = tokptr;
1652       return (GDB_VARIABLE);
1653     }
1654
1655   /* Since we didn't match against a register name or convenience
1656      variable, our only choice left is a history value. */
1657
1658   if (*tokptr == '$')
1659     {
1660       negate = 1;
1661       ival = 1;
1662       tokptr++;
1663     }
1664   else
1665     {
1666       negate = 0;
1667       ival = 0;
1668     }
1669
1670   /* Attempt to decode more characters as an integer value giving
1671      the index in the history list.  If successful, the value will
1672      overwrite ival (currently 0 or 1), and if not, ival will be
1673      left alone, which is good since it is currently correct for
1674      the '$' or '$$' case. */
1675
1676   decode_integer_literal (&ival, &tokptr);
1677   yylval.lval = negate ? -ival : ival;
1678   lexptr = tokptr;
1679   return (GDB_LAST);
1680 }
1681
1682 struct token
1683 {
1684   char *operator;
1685   int token;
1686 };
1687
1688 static const struct token idtokentab[] =
1689 {
1690     { "length", LENGTH },
1691     { "lower", LOWER },
1692     { "upper", UPPER },
1693     { "andif", ANDIF },
1694     { "pred", PRED },
1695     { "succ", SUCC },
1696     { "card", CARD },
1697     { "size", SIZE },
1698     { "orif", ORIF },
1699     { "num", NUM },
1700     { "abs", ABS },
1701     { "max", MAX_TOKEN },
1702     { "min", MIN_TOKEN },
1703     { "mod", MOD },
1704     { "rem", REM },
1705     { "not", NOT },
1706     { "xor", LOGXOR },
1707     { "and", LOGAND },
1708     { "in", IN },
1709     { "or", LOGIOR }
1710 };
1711
1712 static const struct token tokentab2[] =
1713 {
1714     { ":=", GDB_ASSIGNMENT },
1715     { "//", SLASH_SLASH },
1716     { "->", POINTER },
1717     { "/=", NOTEQUAL },
1718     { "<=", LEQ },
1719     { ">=", GTR }
1720 };
1721
1722 /* Read one token, getting characters through lexptr.  */
1723 /* This is where we will check to make sure that the language and the
1724    operators used are compatible.  */
1725
1726 static int
1727 yylex ()
1728 {
1729     unsigned int i;
1730     int token;
1731     char *inputname;
1732     struct symbol *sym;
1733
1734     /* Skip over any leading whitespace. */
1735     while (isspace (*lexptr))
1736         {
1737             lexptr++;
1738         }
1739     /* Look for special single character cases which can't be the first
1740        character of some other multicharacter token. */
1741     switch (*lexptr)
1742         {
1743             case '\0':
1744                 return (0);
1745             case ',':
1746             case '=':
1747             case ';':
1748             case '!':
1749             case '+':
1750             case '*':
1751             case '(':
1752             case ')':
1753             case '[':
1754             case ']':
1755                 return (*lexptr++);
1756         }
1757     /* Look for characters which start a particular kind of multicharacter
1758        token, such as a character literal, register name, convenience
1759        variable name, string literal, etc. */
1760     switch (*lexptr)
1761       {
1762         case '\'':
1763         case '\"':
1764           /* First try to match a string literal, which is any
1765              sequence of characters enclosed in matching single or double
1766              quotes, except that a single character inside single quotes
1767              is a character literal, so we have to catch that case also. */
1768           token = match_string_literal ();
1769           if (token != 0)
1770             {
1771               return (token);
1772             }
1773           if (*lexptr == '\'')
1774             {
1775               token = match_character_literal ();
1776               if (token != 0)
1777                 {
1778                   return (token);
1779                 }
1780             }
1781           break;
1782         case 'C':
1783         case 'c':
1784           token = match_character_literal ();
1785           if (token != 0)
1786             {
1787               return (token);
1788             }
1789           break;
1790         case '$':
1791           token = match_dollar_tokens ();
1792           if (token != 0)
1793             {
1794               return (token);
1795             }
1796           break;
1797       }
1798     /* See if it is a special token of length 2.  */
1799     for (i = 0; i < sizeof (tokentab2) / sizeof (tokentab2[0]); i++)
1800         {
1801             if (STREQN (lexptr, tokentab2[i].operator, 2))
1802                 {
1803                     lexptr += 2;
1804                     return (tokentab2[i].token);
1805                 }
1806         }
1807     /* Look for single character cases which which could be the first
1808        character of some other multicharacter token, but aren't, or we
1809        would already have found it. */
1810     switch (*lexptr)
1811         {
1812             case '-':
1813             case ':':
1814             case '/':
1815             case '<':
1816             case '>':
1817                 return (*lexptr++);
1818         }
1819     /* Look for a float literal before looking for an integer literal, so
1820        we match as much of the input stream as possible. */
1821     token = match_float_literal ();
1822     if (token != 0)
1823         {
1824             return (token);
1825         }
1826     token = match_bitstring_literal ();
1827     if (token != 0)
1828         {
1829             return (token);
1830         }
1831     token = match_integer_literal ();
1832     if (token != 0)
1833         {
1834             return (token);
1835         }
1836
1837     /* Try to match a simple name string, and if a match is found, then
1838        further classify what sort of name it is and return an appropriate
1839        token.  Note that attempting to match a simple name string consumes
1840        the token from lexptr, so we can't back out if we later find that
1841        we can't classify what sort of name it is. */
1842
1843     inputname = match_simple_name_string ();
1844
1845     if (inputname != NULL)
1846       {
1847         char *simplename = (char*) alloca (strlen (inputname));
1848
1849         char *dptr = simplename, *sptr = inputname;
1850         for (; *sptr; sptr++)
1851           *dptr++ = isupper (*sptr) ? tolower(*sptr) : *sptr;
1852
1853         /* See if it is a reserved identifier. */
1854         for (i = 0; i < sizeof (idtokentab) / sizeof (idtokentab[0]); i++)
1855             {
1856                 if (STREQ (simplename, idtokentab[i].operator))
1857                     {
1858                         return (idtokentab[i].token);
1859                     }
1860             }
1861
1862         /* Look for other special tokens. */
1863         if (STREQ (simplename, "true"))
1864             {
1865                 yylval.ulval = 1;
1866                 return (BOOLEAN_LITERAL);
1867             }
1868         if (STREQ (simplename, "false"))
1869             {
1870                 yylval.ulval = 0;
1871                 return (BOOLEAN_LITERAL);
1872             }
1873
1874         sym = lookup_symbol (inputname, expression_context_block,
1875                              VAR_NAMESPACE, (int *) NULL,
1876                              (struct symtab **) NULL);
1877         if (sym == NULL && strcmp (inputname, simplename) != 0)
1878           {
1879             sym = lookup_symbol (simplename, expression_context_block,
1880                                  VAR_NAMESPACE, (int *) NULL,
1881                                  (struct symtab **) NULL);
1882           }
1883         if (sym != NULL)
1884           {
1885             yylval.ssym.stoken.ptr = NULL;
1886             yylval.ssym.stoken.length = 0;
1887             yylval.ssym.sym = sym;
1888             yylval.ssym.is_a_field_of_this = 0; /* FIXME, C++'ism */
1889             switch (SYMBOL_CLASS (sym))
1890               {
1891               case LOC_BLOCK:
1892                 /* Found a procedure name. */
1893                 return (GENERAL_PROCEDURE_NAME);
1894               case LOC_STATIC:
1895                 /* Found a global or local static variable. */
1896                 return (LOCATION_NAME);
1897               case LOC_REGISTER:
1898               case LOC_ARG:
1899               case LOC_REF_ARG:
1900               case LOC_REGPARM:
1901               case LOC_REGPARM_ADDR:
1902               case LOC_LOCAL:
1903               case LOC_LOCAL_ARG:
1904               case LOC_BASEREG:
1905               case LOC_BASEREG_ARG:
1906                 if (innermost_block == NULL
1907                     || contained_in (block_found, innermost_block))
1908                   {
1909                     innermost_block = block_found;
1910                   }
1911                 return (LOCATION_NAME);
1912                 break;
1913               case LOC_CONST:
1914               case LOC_LABEL:
1915                 return (LOCATION_NAME);
1916                 break;
1917               case LOC_TYPEDEF:
1918                 yylval.tsym.type = SYMBOL_TYPE (sym);
1919                 return TYPENAME;
1920               case LOC_UNDEF:
1921               case LOC_CONST_BYTES:
1922               case LOC_OPTIMIZED_OUT:
1923                 error ("Symbol \"%s\" names no location.", inputname);
1924                 break;
1925               }
1926           }
1927         else if (!have_full_symbols () && !have_partial_symbols ())
1928           {
1929             error ("No symbol table is loaded.  Use the \"file\" command.");
1930           }
1931         else
1932           {
1933             error ("No symbol \"%s\" in current context.", inputname);
1934           }
1935       }
1936
1937     /* Catch single character tokens which are not part of some
1938        longer token. */
1939
1940     switch (*lexptr)
1941       {
1942         case '.':                       /* Not float for example. */
1943           lexptr++;
1944           while (isspace (*lexptr)) lexptr++;
1945           inputname = match_simple_name_string ();
1946           if (!inputname)
1947             return '.';
1948           return FIELD_NAME;
1949       }
1950
1951     return (ILLEGAL_TOKEN);
1952 }
1953
1954 void
1955 yyerror (msg)
1956      char *msg;
1957 {
1958   error ("A %s in expression, near `%s'.", (msg ? msg : "error"), lexptr);
1959 }