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 #define yylhs   chill_yylhs
 105 #define yylen   chill_yylen
 106 #define yydefred chill_yydefred
 107 #define yydgoto chill_yydgoto
 108 #define yysindex chill_yysindex
 109 #define yyrindex chill_yyrindex
 110 #define yygindex chill_yygindex
 111 #define yytable  chill_yytable
 112 #define yycheck  chill_yycheck
 113
 114 #ifndef YYDEBUG
 115 #define YYDEBUG 0               /* Default to no yydebug support */
 116 #endif
 117
 118 int
 119 yyparse PARAMS ((void));
 120
 121 static int
 122 yylex PARAMS ((void));
 123
 124 void
 125 yyerror PARAMS ((char *));
 126
 127 %}
 128
 129 /* Although the yacc "value" of an expression is not used,
 130    since the result is stored in the structure being created,
 131    other node types do have values.  */
 132
 133 %union
 134   {
 135     LONGEST lval;
 136     unsigned LONGEST ulval;
 137     struct {
 138       LONGEST val;
 139       struct type *type;
 140     } typed_val;
 141     double dval;
 142     struct symbol *sym;
 143     struct type *tval;
 144     struct stoken sval;
 145     struct ttype tsym;
 146     struct symtoken ssym;
 147     int voidval;
 148     struct block *bval;
 149     enum exp_opcode opcode;
 150     struct internalvar *ivar;
 151
 152     struct type **tvec;
 153     int *ivec;
 154   }
 155
 156 %token <voidval> FIXME_01
 157 %token <voidval> FIXME_02
 158 %token <voidval> FIXME_03
 159 %token <voidval> FIXME_04
 160 %token <voidval> FIXME_05
 161 %token <voidval> FIXME_06
 162 %token <voidval> FIXME_07
 163 %token <voidval> FIXME_08
 164 %token <voidval> FIXME_09
 165 %token <voidval> FIXME_10
 166 %token <voidval> FIXME_11
 167 %token <voidval> FIXME_12
 168 %token <voidval> FIXME_13
 169 %token <voidval> FIXME_14
 170 %token <voidval> FIXME_15
 171 %token <voidval> FIXME_16
 172 %token <voidval> FIXME_17
 173 %token <voidval> FIXME_18
 174 %token <voidval> FIXME_19
 175 %token <voidval> FIXME_20
 176 %token <voidval> FIXME_21
 177 %token <voidval> FIXME_22
 178 %token <voidval> FIXME_24
 179 %token <voidval> FIXME_25
 180 %token <voidval> FIXME_26
 181 %token <voidval> FIXME_27
 182 %token <voidval> FIXME_28
 183 %token <voidval> FIXME_29
 184 %token <voidval> FIXME_30
 185
 186 %token <typed_val>      INTEGER_LITERAL
 187 %token <ulval>          BOOLEAN_LITERAL
 188 %token <typed_val>      CHARACTER_LITERAL
 189 %token <dval>           FLOAT_LITERAL
 190 %token <ssym>           GENERAL_PROCEDURE_NAME
 191 %token <ssym>           LOCATION_NAME
 192 %token <voidval>        SET_LITERAL
 193 %token <voidval>        EMPTINESS_LITERAL
 194 %token <sval>           CHARACTER_STRING_LITERAL
 195 %token <sval>           BIT_STRING_LITERAL
 196 %token <tsym>           TYPENAME
 197 %token <sval>           FIELD_NAME
 198
 199 %token <voidval>        '.'
 200 %token <voidval>        ';'
 201 %token <voidval>        ':'
 202 %token <voidval>        CASE
 203 %token <voidval>        OF
 204 %token <voidval>        ESAC
 205 %token <voidval>        LOGIOR
 206 %token <voidval>        ORIF
 207 %token <voidval>        LOGXOR
 208 %token <voidval>        LOGAND
 209 %token <voidval>        ANDIF
 210 %token <voidval>        '='
 211 %token <voidval>        NOTEQUAL
 212 %token <voidval>        '>'
 213 %token <voidval>        GTR
 214 %token <voidval>        '<'
 215 %token <voidval>        LEQ
 216 %token <voidval>        IN
 217 %token <voidval>        '+'
 218 %token <voidval>        '-'
 219 %token <voidval>        '*'
 220 %token <voidval>        '/'
 221 %token <voidval>        SLASH_SLASH
 222 %token <voidval>        MOD
 223 %token <voidval>        REM
 224 %token <voidval>        NOT
 225 %token <voidval>        POINTER
 226 %token <voidval>        RECEIVE
 227 %token <voidval>        '['
 228 %token <voidval>        ']'
 229 %token <voidval>        '('
 230 %token <voidval>        ')'
 231 %token <voidval>        UP
 232 %token <voidval>        IF
 233 %token <voidval>        THEN
 234 %token <voidval>        ELSE
 235 %token <voidval>        FI
 236 %token <voidval>        ELSIF
 237 %token <voidval>        ILLEGAL_TOKEN
 238 %token <voidval>        NUM
 239 %token <voidval>        PRED
 240 %token <voidval>        SUCC
 241 %token <voidval>        ABS
 242 %token <voidval>        CARD
 243 %token <voidval>        MAX_TOKEN
 244 %token <voidval>        MIN_TOKEN
 245 %token <voidval>        SIZE
 246 %token <voidval>        UPPER
 247 %token <voidval>        LOWER
 248 %token <voidval>        LENGTH
 249 %token <voidval>        ARRAY
 250
 251 /* Tokens which are not Chill tokens used in expressions, but rather GDB
 252    specific things that we recognize in the same context as Chill tokens
 253    (register names for example). */
 254
 255 %token <lval>           GDB_REGNAME     /* Machine register name */
 256 %token <lval>           GDB_LAST        /* Value history */
 257 %token <ivar>           GDB_VARIABLE    /* Convenience variable */
 258 %token <voidval>        GDB_ASSIGNMENT  /* Assign value to somewhere */
 259
 260 %type <voidval>         access_name
 261 %type <voidval>         primitive_value
 262 %type <voidval>         value_name
 263 %type <voidval>         literal
 264 %type <voidval>         tuple
 265 %type <voidval>         slice
 266 %type <voidval>         expression_conversion
 267 %type <voidval>         value_procedure_call
 268 %type <voidval>         value_built_in_routine_call
 269 %type <voidval>         chill_value_built_in_routine_call
 270 %type <voidval>         start_expression
 271 %type <voidval>         zero_adic_operator
 272 %type <voidval>         parenthesised_expression
 273 %type <voidval>         value
 274 %type <voidval>         undefined_value
 275 %type <voidval>         expression
 276 %type <voidval>         conditional_expression
 277 %type <voidval>         then_alternative
 278 %type <voidval>         else_alternative
 279 %type <voidval>         sub_expression
 280 %type <voidval>         value_case_alternative
 281 %type <voidval>         operand_0
 282 %type <voidval>         operand_1
 283 %type <voidval>         operand_2
 284 %type <voidval>         operand_3
 285 %type <voidval>         operand_4
 286 %type <voidval>         operand_5
 287 %type <voidval>         operand_6
 288 %type <voidval>         synonym_name
 289 %type <voidval>         value_enumeration_name
 290 %type <voidval>         value_do_with_name
 291 %type <voidval>         value_receive_name
 292 %type <voidval>         expression_list
 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 %type <lval>            rparen
 307
 308 %%
 309
 310 /* Z.200, 5.3.1 */
 311
 312 start   :       value { }
 313         |       mode_name
 314                         { write_exp_elt_opcode(OP_TYPE);
 315                           write_exp_elt_type($1.type);
 316                           write_exp_elt_opcode(OP_TYPE);}
 317         ;
 318
 319 value           :       expression
 320                         {
 321                           $$ = 0;       /* FIXME */
 322                         }
 323                 |       undefined_value
 324                         {
 325                           $$ = 0;       /* FIXME */
 326                         }
 327                 ;
 328
 329 undefined_value :       FIXME_01
 330                         {
 331                           $$ = 0;       /* FIXME */
 332                         }
 333                 ;
 334
 335 /* Z.200, 4.2.2 */
 336
 337 access_name     :       LOCATION_NAME
 338                         {
 339                           write_exp_elt_opcode (OP_VAR_VALUE);
 340                           write_exp_elt_block (NULL);
 341                           write_exp_elt_sym ($1.sym);
 342                           write_exp_elt_opcode (OP_VAR_VALUE);
 343                         }
 344                 |       GDB_LAST                /* gdb specific */
 345                         {
 346                           write_exp_elt_opcode (OP_LAST);
 347                           write_exp_elt_longcst ($1);
 348                           write_exp_elt_opcode (OP_LAST);
 349                         }
 350                 |       GDB_REGNAME             /* gdb specific */
 351                         {
 352                           write_exp_elt_opcode (OP_REGISTER);
 353                           write_exp_elt_longcst ($1);
 354                           write_exp_elt_opcode (OP_REGISTER);
 355                         }
 356                 |       GDB_VARIABLE    /* gdb specific */
 357                         {
 358                           write_exp_elt_opcode (OP_INTERNALVAR);
 359                           write_exp_elt_intern ($1);
 360                           write_exp_elt_opcode (OP_INTERNALVAR);
 361                         }
 362                 |       FIXME_03
 363                         {
 364                           $$ = 0;       /* FIXME */
 365                         }
 366                 ;
 367
 368 /* Z.200, 4.2.8 */
 369
 370 expression_list :       expression
 371                         {
 372                           arglist_len = 1;
 373                         }
 374                 |       expression_list ',' expression
 375                         {
 376                           arglist_len++;
 377                         }
 378                 ;
 379
 380 maybe_expression_list:  /* EMPTY */
 381                         {
 382                           arglist_len = 0;
 383                         }
 384                 |       expression_list
 385                 ;
 386
 387
 388 /* Z.200, 5.2.1 */
 389
 390 primitive_value_lparen: primitive_value '('
 391                                 /* This is to save the value of arglist_len
 392                                    being accumulated for each dimension. */
 393                                 { start_arglist (); }
 394                 ;
 395
 396 rparen          :       ')'
 397                                 { $$ = end_arglist (); }
 398                 ;
 399
 400 primitive_value :
 401                         access_name
 402                 |       primitive_value_lparen maybe_expression_list rparen
 403                         {
 404                           write_exp_elt_opcode (MULTI_SUBSCRIPT);
 405                           write_exp_elt_longcst ($3);
 406                           write_exp_elt_opcode (MULTI_SUBSCRIPT);
 407                         }
 408                 |       primitive_value FIELD_NAME
 409                         { write_exp_elt_opcode (STRUCTOP_STRUCT);
 410                           write_exp_string ($2);
 411                           write_exp_elt_opcode (STRUCTOP_STRUCT);
 412                         }
 413                 |       primitive_value POINTER
 414                         {
 415                           write_exp_elt_opcode (UNOP_IND);
 416                         }
 417                 |       value_name
 418                         {
 419                           $$ = 0;       /* FIXME */
 420                         }
 421                 |       literal
 422                         {
 423                           $$ = 0;       /* FIXME */
 424                         }
 425                 |       tuple
 426                         {
 427                           $$ = 0;       /* FIXME */
 428                         }
 429                 |       slice
 430                         {
 431                           $$ = 0;       /* FIXME */
 432                         }
 433                 |       expression_conversion
 434                         {
 435                           $$ = 0;       /* FIXME */
 436                         }
 437                 |       value_procedure_call
 438                         {
 439                           $$ = 0;       /* FIXME */
 440                         }
 441                 |       value_built_in_routine_call
 442                         {
 443                           $$ = 0;       /* FIXME */
 444                         }
 445                 |       start_expression
 446                         {
 447                           $$ = 0;       /* FIXME */
 448                         }
 449                 |       zero_adic_operator
 450                         {
 451                           $$ = 0;       /* FIXME */
 452                         }
 453                 |       parenthesised_expression
 454                         {
 455                           $$ = 0;       /* FIXME */
 456                         }
 457                 ;
 458
 459 /* Z.200, 5.2.3 */
 460
 461 value_name      :       synonym_name
 462                         {
 463                           $$ = 0;       /* FIXME */
 464                         }
 465                 |       value_enumeration_name
 466                         {
 467                           $$ = 0;       /* FIXME */
 468                         }
 469                 |       value_do_with_name
 470                         {
 471                           $$ = 0;       /* FIXME */
 472                         }
 473                 |       value_receive_name
 474                         {
 475                           $$ = 0;       /* FIXME */
 476                         }
 477                 |       GENERAL_PROCEDURE_NAME
 478                         {
 479                           write_exp_elt_opcode (OP_VAR_VALUE);
 480                           write_exp_elt_block (NULL);
 481                           write_exp_elt_sym ($1.sym);
 482                           write_exp_elt_opcode (OP_VAR_VALUE);
 483                         }
 484                 ;
 485
 486 /* Z.200, 5.2.4.1 */
 487
 488 literal         :       INTEGER_LITERAL
 489                         {
 490                           write_exp_elt_opcode (OP_LONG);
 491                           write_exp_elt_type ($1.type);
 492                           write_exp_elt_longcst ((LONGEST) ($1.val));
 493                           write_exp_elt_opcode (OP_LONG);
 494                         }
 495                 |       BOOLEAN_LITERAL
 496                         {
 497                           write_exp_elt_opcode (OP_BOOL);
 498                           write_exp_elt_longcst ((LONGEST) $1);
 499                           write_exp_elt_opcode (OP_BOOL);
 500                         }
 501                 |       CHARACTER_LITERAL
 502                         {
 503                           write_exp_elt_opcode (OP_LONG);
 504                           write_exp_elt_type ($1.type);
 505                           write_exp_elt_longcst ((LONGEST) ($1.val));
 506                           write_exp_elt_opcode (OP_LONG);
 507                         }
 508                 |       FLOAT_LITERAL
 509                         {
 510                           write_exp_elt_opcode (OP_DOUBLE);
 511                           write_exp_elt_type (builtin_type_double);
 512                           write_exp_elt_dblcst ($1);
 513                           write_exp_elt_opcode (OP_DOUBLE);
 514                         }
 515                 |       SET_LITERAL
 516                         {
 517                           $$ = 0;       /* FIXME */
 518                         }
 519                 |       EMPTINESS_LITERAL
 520                         {
 521                           struct type *void_ptr_type
 522                             = lookup_pointer_type (builtin_type_void);
 523                           write_exp_elt_opcode (OP_LONG);
 524                           write_exp_elt_type (void_ptr_type);
 525                           write_exp_elt_longcst (0);
 526                           write_exp_elt_opcode (OP_LONG);
 527                         }
 528                 |       CHARACTER_STRING_LITERAL
 529                         {
 530                           write_exp_elt_opcode (OP_STRING);
 531                           write_exp_string ($1);
 532                           write_exp_elt_opcode (OP_STRING);
 533                         }
 534                 |       BIT_STRING_LITERAL
 535                         {
 536                           write_exp_elt_opcode (OP_BITSTRING);
 537                           write_exp_bitstring ($1);
 538                           write_exp_elt_opcode (OP_BITSTRING);
 539                         }
 540                 ;
 541
 542 /* Z.200, 5.2.5 */
 543
 544 tuple_element   :       expression
 545                 |       named_record_element
 546                 ;
 547
 548 named_record_element:   FIELD_NAME ',' named_record_element
 549                         { write_exp_elt_opcode (OP_LABELED);
 550                           write_exp_string ($1);
 551                           write_exp_elt_opcode (OP_LABELED);
 552                         }
 553                 |       FIELD_NAME ':' expression
 554                         { write_exp_elt_opcode (OP_LABELED);
 555                           write_exp_string ($1);
 556                           write_exp_elt_opcode (OP_LABELED);
 557                         }
 558                 ;
 559
 560 tuple_elements  :       tuple_element
 561                         {
 562                           arglist_len = 1;
 563                         }
 564                 |       tuple_elements ',' tuple_element
 565                         {
 566                           arglist_len++;
 567                         }
 568                 ;
 569
 570 maybe_tuple_elements :  tuple_elements
 571                 | /* EMPTY */
 572                 ;
 573
 574 tuple   :       '['
 575                         { start_arglist (); }
 576                 maybe_tuple_elements ']'
 577                         {
 578                           write_exp_elt_opcode (OP_ARRAY);
 579                           write_exp_elt_longcst ((LONGEST) 0);
 580                           write_exp_elt_longcst ((LONGEST) end_arglist () - 1);
 581                           write_exp_elt_opcode (OP_ARRAY);
 582                         }
 583                 |
 584                 mode_name '['
 585                         { start_arglist (); }
 586                 maybe_tuple_elements ']'
 587                         {
 588                           write_exp_elt_opcode (OP_ARRAY);
 589                           write_exp_elt_longcst ((LONGEST) 0);
 590                           write_exp_elt_longcst ((LONGEST) end_arglist () - 1);
 591                           write_exp_elt_opcode (OP_ARRAY);
 592
 593                           write_exp_elt_opcode (UNOP_CAST);
 594                           write_exp_elt_type ($1.type);
 595                           write_exp_elt_opcode (UNOP_CAST);
 596                         }
 597                 ;
 598
 599
 600 /* Z.200, 5.2.6 */
 601
 602
 603 slice:  primitive_value_lparen expression ':' expression rparen
 604                         {
 605                           write_exp_elt_opcode (TERNOP_SLICE);
 606                         }
 607                 |       primitive_value_lparen expression UP expression rparen
 608                         {
 609                           write_exp_elt_opcode (TERNOP_SLICE_COUNT);
 610                         }
 611                 ;
 612
 613 /* Z.200, 5.2.11 */
 614
 615 expression_conversion:  mode_name parenthesised_expression
 616                         {
 617                           write_exp_elt_opcode (UNOP_CAST);
 618                           write_exp_elt_type ($1.type);
 619                           write_exp_elt_opcode (UNOP_CAST);
 620                         }
 621                 |       ARRAY '(' ')' mode_name parenthesised_expression
 622                         /* This is pseudo-Chill, similar to C's '(TYPE[])EXPR'
 623                            which casts to an artificial array. */
 624                         {
 625                           struct type *range_type
 626                             = create_range_type ((struct type *) NULL,
 627                                                  builtin_type_int, 0, 0);
 628                           struct type *array_type
 629                             = create_array_type ((struct type *) NULL,
 630                                                  $4.type, range_type);
 631                           TYPE_ARRAY_UPPER_BOUND_TYPE(array_type)
 632                             = BOUND_CANNOT_BE_DETERMINED;
 633                           write_exp_elt_opcode (UNOP_CAST);
 634                           write_exp_elt_type (array_type);
 635                           write_exp_elt_opcode (UNOP_CAST);
 636                         }
 637                 ;
 638
 639 /* Z.200, 5.2.12 */
 640
 641 value_procedure_call:   FIXME_05
 642                         {
 643                           $$ = 0;       /* FIXME */
 644                         }
 645                 ;
 646
 647 /* Z.200, 5.2.13 */
 648
 649 value_built_in_routine_call:    chill_value_built_in_routine_call
 650                         {
 651                           $$ = 0;       /* FIXME */
 652                         }
 653                 ;
 654
 655 /* Z.200, 5.2.14 */
 656
 657 start_expression:       FIXME_06
 658                         {
 659                           $$ = 0;       /* FIXME */
 660                         }       /* Not in GNU-Chill */
 661                 ;
 662
 663 /* Z.200, 5.2.15 */
 664
 665 zero_adic_operator:     FIXME_07
 666                         {
 667                           $$ = 0;       /* FIXME */
 668                         }
 669                 ;
 670
 671 /* Z.200, 5.2.16 */
 672
 673 parenthesised_expression:       '(' expression ')'
 674                         {
 675                           $$ = 0;       /* FIXME */
 676                         }
 677                 ;
 678
 679 /* Z.200, 5.3.2 */
 680
 681 expression      :       operand_0
 682                         {
 683                           $$ = 0;       /* FIXME */
 684                         }
 685                 |       single_assignment_action
 686                         {
 687                           $$ = 0;       /* FIXME */
 688                         }
 689                 |       conditional_expression
 690                         {
 691                           $$ = 0;       /* FIXME */
 692                         }
 693                 ;
 694
 695 conditional_expression : IF boolean_expression then_alternative else_alternative FI
 696                         {
 697                           $$ = 0;       /* FIXME */
 698                         }
 699                 |       CASE case_selector_list OF value_case_alternative ELSE sub_expression ESAC
 700                         {
 701                           $$ = 0;       /* FIXME */
 702                         }
 703                 ;
 704
 705 then_alternative:       THEN subexpression
 706                         {
 707                           $$ = 0;       /* FIXME */
 708                         }
 709                 ;
 710
 711 else_alternative:       ELSE subexpression
 712                         {
 713                           $$ = 0;       /* FIXME */
 714                         }
 715                 |       ELSIF boolean_expression then_alternative else_alternative
 716                         {
 717                           $$ = 0;       /* FIXME */
 718                         }
 719                 ;
 720
 721 sub_expression  :       expression
 722                         {
 723                           $$ = 0;       /* FIXME */
 724                         }
 725                 ;
 726
 727 value_case_alternative: case_label_specification ':' sub_expression ';'
 728                         {
 729                           $$ = 0;       /* FIXME */
 730                         }
 731                 ;
 732
 733 /* Z.200, 5.3.3 */
 734
 735 operand_0       :       operand_1
 736                         {
 737                           $$ = 0;       /* FIXME */
 738                         }
 739                 |       operand_0 LOGIOR operand_1
 740                         {
 741                           write_exp_elt_opcode (BINOP_BITWISE_IOR);
 742                         }
 743                 |       operand_0 ORIF operand_1
 744                         {
 745                           $$ = 0;       /* FIXME */
 746                         }
 747                 |       operand_0 LOGXOR operand_1
 748                         {
 749                           write_exp_elt_opcode (BINOP_BITWISE_XOR);
 750                         }
 751                 ;
 752
 753 /* Z.200, 5.3.4 */
 754
 755 operand_1       :       operand_2
 756                         {
 757                           $$ = 0;       /* FIXME */
 758                         }
 759                 |       operand_1 LOGAND operand_2
 760                         {
 761                           write_exp_elt_opcode (BINOP_BITWISE_AND);
 762                         }
 763                 |       operand_1 ANDIF operand_2
 764                         {
 765                           $$ = 0;       /* FIXME */
 766                         }
 767                 ;
 768
 769 /* Z.200, 5.3.5 */
 770
 771 operand_2       :       operand_3
 772                         {
 773                           $$ = 0;       /* FIXME */
 774                         }
 775                 |       operand_2 '=' operand_3
 776                         {
 777                           write_exp_elt_opcode (BINOP_EQUAL);
 778                         }
 779                 |       operand_2 NOTEQUAL operand_3
 780                         {
 781                           write_exp_elt_opcode (BINOP_NOTEQUAL);
 782                         }
 783                 |       operand_2 '>' operand_3
 784                         {
 785                           write_exp_elt_opcode (BINOP_GTR);
 786                         }
 787                 |       operand_2 GTR operand_3
 788                         {
 789                           write_exp_elt_opcode (BINOP_GEQ);
 790                         }
 791                 |       operand_2 '<' operand_3
 792                         {
 793                           write_exp_elt_opcode (BINOP_LESS);
 794                         }
 795                 |       operand_2 LEQ operand_3
 796                         {
 797                           write_exp_elt_opcode (BINOP_LEQ);
 798                         }
 799                 |       operand_2 IN operand_3
 800                         {
 801                           write_exp_elt_opcode (BINOP_IN);
 802                         }
 803                 ;
 804
 805
 806 /* Z.200, 5.3.6 */
 807
 808 operand_3       :       operand_4
 809                         {
 810                           $$ = 0;       /* FIXME */
 811                         }
 812                 |       operand_3 '+' operand_4
 813                         {
 814                           write_exp_elt_opcode (BINOP_ADD);
 815                         }
 816                 |       operand_3 '-' operand_4
 817                         {
 818                           write_exp_elt_opcode (BINOP_SUB);
 819                         }
 820                 |       operand_3 SLASH_SLASH operand_4
 821                         {
 822                           write_exp_elt_opcode (BINOP_CONCAT);
 823                         }
 824                 ;
 825
 826 /* Z.200, 5.3.7 */
 827
 828 operand_4       :       operand_5
 829                         {
 830                           $$ = 0;       /* FIXME */
 831                         }
 832                 |       operand_4 '*' operand_5
 833                         {
 834                           write_exp_elt_opcode (BINOP_MUL);
 835                         }
 836                 |       operand_4 '/' operand_5
 837                         {
 838                           write_exp_elt_opcode (BINOP_DIV);
 839                         }
 840                 |       operand_4 MOD operand_5
 841                         {
 842                           write_exp_elt_opcode (BINOP_MOD);
 843                         }
 844                 |       operand_4 REM operand_5
 845                         {
 846                           write_exp_elt_opcode (BINOP_REM);
 847                         }
 848                 ;
 849
 850 /* Z.200, 5.3.8 */
 851
 852 operand_5       :       operand_6
 853                         {
 854                           $$ = 0;       /* FIXME */
 855                         }
 856                 |       '-' operand_6
 857                         {
 858                           write_exp_elt_opcode (UNOP_NEG);
 859                         }
 860                 |       NOT operand_6
 861                         {
 862                           write_exp_elt_opcode (UNOP_LOGICAL_NOT);
 863                         }
 864                 |       parenthesised_expression literal
 865 /* We require the string operand to be a literal, to avoid some
 866    nasty parsing ambiguities. */
 867                         {
 868                           write_exp_elt_opcode (BINOP_CONCAT);
 869                         }
 870                 ;
 871
 872 /* Z.200, 5.3.9 */
 873
 874 operand_6       :       POINTER primitive_value
 875                         {
 876                           write_exp_elt_opcode (UNOP_ADDR);
 877                         }
 878                 |       RECEIVE buffer_location
 879                         {
 880                           $$ = 0;       /* FIXME */
 881                         }
 882                 |       primitive_value
 883                         {
 884                           $$ = 0;       /* FIXME */
 885                         }
 886                 ;
 887
 888
 889 /* Z.200, 6.2 */
 890
 891 single_assignment_action :
 892                         primitive_value GDB_ASSIGNMENT value
 893                         {
 894                           write_exp_elt_opcode (BINOP_ASSIGN);
 895                         }
 896                 ;
 897
 898 /* Z.200, 6.20.3 */
 899
 900 chill_value_built_in_routine_call :
 901                         NUM '(' expression ')'
 902                         {
 903                           $$ = 0;       /* FIXME */
 904                         }
 905                 |       PRED '(' expression ')'
 906                         {
 907                           $$ = 0;       /* FIXME */
 908                         }
 909                 |       SUCC '(' expression ')'
 910                         {
 911                           $$ = 0;       /* FIXME */
 912                         }
 913                 |       ABS '(' expression ')'
 914                         {
 915                           $$ = 0;       /* FIXME */
 916                         }
 917                 |       CARD '(' expression ')'
 918                         {
 919                           $$ = 0;       /* FIXME */
 920                         }
 921                 |       MAX_TOKEN '(' expression ')'
 922                         {
 923                           $$ = 0;       /* FIXME */
 924                         }
 925                 |       MIN_TOKEN '(' expression ')'
 926                         {
 927                           $$ = 0;       /* FIXME */
 928                         }
 929                 |       SIZE '(' expression ')'
 930                         { write_exp_elt_opcode (UNOP_SIZEOF); }
 931                 |       SIZE '(' mode_argument ')'
 932                         { write_exp_elt_opcode (OP_LONG);
 933                           write_exp_elt_type (builtin_type_int);
 934                           write_exp_elt_longcst ((LONGEST) TYPE_LENGTH ($3));
 935                           write_exp_elt_opcode (OP_LONG); }
 936                 |       UPPER '(' upper_lower_argument ')'
 937                         {
 938                           $$ = 0;       /* FIXME */
 939                         }
 940                 |       LOWER '(' upper_lower_argument ')'
 941                         {
 942                           $$ = 0;       /* FIXME */
 943                         }
 944                 |       LENGTH '(' length_argument ')'
 945                         {
 946                           $$ = 0;       /* FIXME */
 947                         }
 948                 ;
 949
 950 mode_argument :         mode_name
 951                         {
 952                           $$ = $1.type;
 953                         }
 954                 |       array_mode_name '(' expression ')'
 955                         {
 956                           $$ = 0;       /* FIXME */
 957                         }
 958                 |       string_mode_name '(' expression ')'
 959                         {
 960                           $$ = 0;       /* FIXME */
 961                         }
 962                 |       variant_structure_mode_name '(' expression_list ')'
 963                         {
 964                           $$ = 0;       /* FIXME */
 965                         }
 966                 ;
 967
 968 mode_name :             TYPENAME
 969                 ;
 970
 971 upper_lower_argument :  expression
 972                         {
 973                           $$ = 0;       /* FIXME */
 974                         }
 975                 |       mode_name
 976                         {
 977                           $$ = 0;       /* FIXME */
 978                         }
 979                 ;
 980
 981 length_argument :       expression
 982                         {
 983                           $$ = 0;       /* FIXME */
 984                         }
 985                 ;
 986
 987 /* Things which still need productions... */
 988
 989 array_mode_name         :       FIXME_08 { $$ = 0; }
 990 string_mode_name        :       FIXME_09 { $$ = 0; }
 991 variant_structure_mode_name:    FIXME_10 { $$ = 0; }
 992 synonym_name            :       FIXME_11 { $$ = 0; }
 993 value_enumeration_name  :       FIXME_12 { $$ = 0; }
 994 value_do_with_name      :       FIXME_13 { $$ = 0; }
 995 value_receive_name      :       FIXME_14 { $$ = 0; }
 996 boolean_expression      :       FIXME_26 { $$ = 0; }
 997 case_selector_list      :       FIXME_27 { $$ = 0; }
 998 subexpression           :       FIXME_28 { $$ = 0; }
 999 case_label_specification:       FIXME_29 { $$ = 0; }
1000 buffer_location         :       FIXME_30 { $$ = 0; }
1001
1002 %%
1003
1004 /* Implementation of a dynamically expandable buffer for processing input
1005    characters acquired through lexptr and building a value to return in
1006    yylval. */
1007
1008 static char *tempbuf;           /* Current buffer contents */
1009 static int tempbufsize;         /* Size of allocated buffer */
1010 static int tempbufindex;        /* Current index into buffer */
1011
1012 #define GROWBY_MIN_SIZE 64      /* Minimum amount to grow buffer by */
1013
1014 #define CHECKBUF(size) \
1015   do { \
1016     if (tempbufindex + (size) >= tempbufsize) \
1017       { \
1018         growbuf_by_size (size); \
1019       } \
1020   } while (0);
1021
1022 /* Grow the static temp buffer if necessary, including allocating the first one
1023    on demand. */
1024
1025 static void
1026 growbuf_by_size (count)
1027      int count;
1028 {
1029   int growby;
1030
1031   growby = max (count, GROWBY_MIN_SIZE);
1032   tempbufsize += growby;
1033   if (tempbuf == NULL)
1034     {
1035       tempbuf = (char *) malloc (tempbufsize);
1036     }
1037   else
1038     {
1039       tempbuf = (char *) realloc (tempbuf, tempbufsize);
1040     }
1041 }
1042
1043 /* Try to consume a simple name string token.  If successful, returns
1044    a pointer to a nullbyte terminated copy of the name that can be used
1045    in symbol table lookups.  If not successful, returns NULL. */
1046
1047 static char *
1048 match_simple_name_string ()
1049 {
1050   char *tokptr = lexptr;
1051
1052   if (isalpha (*tokptr) || *tokptr == '_')
1053     {
1054       char *result;
1055       do {
1056         tokptr++;
1057       } while (isalnum (*tokptr) || (*tokptr == '_'));
1058       yylval.sval.ptr = lexptr;
1059       yylval.sval.length = tokptr - lexptr;
1060       lexptr = tokptr;
1061       result = copy_name (yylval.sval);
1062       return result;
1063     }
1064   return (NULL);
1065 }
1066
1067 /* Start looking for a value composed of valid digits as set by the base
1068    in use.  Note that '_' characters are valid anywhere, in any quantity,
1069    and are simply ignored.  Since we must find at least one valid digit,
1070    or reject this token as an integer literal, we keep track of how many
1071    digits we have encountered. */
1072
1073 static int
1074 decode_integer_value (base, tokptrptr, ivalptr)
1075   int base;
1076   char **tokptrptr;
1077   int *ivalptr;
1078 {
1079   char *tokptr = *tokptrptr;
1080   int temp;
1081   int digits = 0;
1082
1083   while (*tokptr != '\0')
1084     {
1085       temp = *tokptr;
1086       if (isupper (temp))
1087         temp = tolower (temp);
1088       tokptr++;
1089       switch (temp)
1090         {
1091         case '_':
1092           continue;
1093         case '0':  case '1':  case '2':  case '3':  case '4':
1094         case '5':  case '6':  case '7':  case '8':  case '9':
1095           temp -= '0';
1096           break;
1097         case 'a':  case 'b':  case 'c':  case 'd':  case 'e': case 'f':
1098           temp -= 'a';
1099           temp += 10;
1100           break;
1101         default:
1102           temp = base;
1103           break;
1104         }
1105       if (temp < base)
1106         {
1107           digits++;
1108           *ivalptr *= base;
1109           *ivalptr += temp;
1110         }
1111       else
1112         {
1113           /* Found something not in domain for current base. */
1114           tokptr--;     /* Unconsume what gave us indigestion. */
1115           break;
1116         }
1117     }
1118
1119   /* If we didn't find any digits, then we don't have a valid integer
1120      value, so reject the entire token.  Otherwise, update the lexical
1121      scan pointer, and return non-zero for success. */
1122
1123   if (digits == 0)
1124     {
1125       return (0);
1126     }
1127   else
1128     {
1129       *tokptrptr = tokptr;
1130       return (1);
1131     }
1132 }
1133
1134 static int
1135 decode_integer_literal (valptr, tokptrptr)
1136   int *valptr;
1137   char **tokptrptr;
1138 {
1139   char *tokptr = *tokptrptr;
1140   int base = 0;
1141   int ival = 0;
1142   int explicit_base = 0;
1143
1144   /* Look for an explicit base specifier, which is optional. */
1145
1146   switch (*tokptr)
1147     {
1148     case 'd':
1149     case 'D':
1150       explicit_base++;
1151       base = 10;
1152       tokptr++;
1153       break;
1154     case 'b':
1155     case 'B':
1156       explicit_base++;
1157       base = 2;
1158       tokptr++;
1159       break;
1160     case 'h':
1161     case 'H':
1162       explicit_base++;
1163       base = 16;
1164       tokptr++;
1165       break;
1166     case 'o':
1167     case 'O':
1168       explicit_base++;
1169       base = 8;
1170       tokptr++;
1171       break;
1172     default:
1173       base = 10;
1174       break;
1175     }
1176
1177   /* If we found an explicit base ensure that the character after the
1178      explicit base is a single quote. */
1179
1180   if (explicit_base && (*tokptr++ != '\''))
1181     {
1182       return (0);
1183     }
1184
1185   /* Attempt to decode whatever follows as an integer value in the
1186      indicated base, updating the token pointer in the process and
1187      computing the value into ival.  Also, if we have an explicit
1188      base, then the next character must not be a single quote, or we
1189      have a bitstring literal, so reject the entire token in this case.
1190      Otherwise, update the lexical scan pointer, and return non-zero
1191      for success. */
1192
1193   if (!decode_integer_value (base, &tokptr, &ival))
1194     {
1195       return (0);
1196     }
1197   else if (explicit_base && (*tokptr == '\''))
1198     {
1199       return (0);
1200     }
1201   else
1202     {
1203       *valptr = ival;
1204       *tokptrptr = tokptr;
1205       return (1);
1206     }
1207 }
1208
1209 /*  If it wasn't for the fact that floating point values can contain '_'
1210     characters, we could just let strtod do all the hard work by letting it
1211     try to consume as much of the current token buffer as possible and
1212     find a legal conversion.  Unfortunately we need to filter out the '_'
1213     characters before calling strtod, which we do by copying the other
1214     legal chars to a local buffer to be converted.  However since we also
1215     need to keep track of where the last unconsumed character in the input
1216     buffer is, we have transfer only as many characters as may compose a
1217     legal floating point value. */
1218
1219 static int
1220 match_float_literal ()
1221 {
1222   char *tokptr = lexptr;
1223   char *buf;
1224   char *copy;
1225   double dval;
1226   extern double strtod ();
1227
1228   /* Make local buffer in which to build the string to convert.  This is
1229      required because underscores are valid in chill floating point numbers
1230      but not in the string passed to strtod to convert.  The string will be
1231      no longer than our input string. */
1232
1233   copy = buf = (char *) alloca (strlen (tokptr) + 1);
1234
1235   /* Transfer all leading digits to the conversion buffer, discarding any
1236      underscores. */
1237
1238   while (isdigit (*tokptr) || *tokptr == '_')
1239     {
1240       if (*tokptr != '_')
1241         {
1242           *copy++ = *tokptr;
1243         }
1244       tokptr++;
1245     }
1246
1247   /* Now accept either a '.', or one of [eEdD].  Dot is legal regardless
1248      of whether we found any leading digits, and we simply accept it and
1249      continue on to look for the fractional part and/or exponent.  One of
1250      [eEdD] is legal only if we have seen digits, and means that there
1251      is no fractional part.  If we find neither of these, then this is
1252      not a floating point number, so return failure. */
1253
1254   switch (*tokptr++)
1255     {
1256       case '.':
1257         /* Accept and then look for fractional part and/or exponent. */
1258         *copy++ = '.';
1259         break;
1260
1261       case 'e':
1262       case 'E':
1263       case 'd':
1264       case 'D':
1265         if (copy == buf)
1266           {
1267             return (0);
1268           }
1269         *copy++ = 'e';
1270         goto collect_exponent;
1271         break;
1272
1273       default:
1274         return (0);
1275         break;
1276     }
1277
1278   /* We found a '.', copy any fractional digits to the conversion buffer, up
1279      to the first nondigit, non-underscore character. */
1280
1281   while (isdigit (*tokptr) || *tokptr == '_')
1282     {
1283       if (*tokptr != '_')
1284         {
1285           *copy++ = *tokptr;
1286         }
1287       tokptr++;
1288     }
1289
1290   /* Look for an exponent, which must start with one of [eEdD].  If none
1291      is found, jump directly to trying to convert what we have collected
1292      so far. */
1293
1294   switch (*tokptr)
1295     {
1296       case 'e':
1297       case 'E':
1298       case 'd':
1299       case 'D':
1300         *copy++ = 'e';
1301         tokptr++;
1302         break;
1303       default:
1304         goto convert_float;
1305         break;
1306     }
1307
1308   /* Accept an optional '-' or '+' following one of [eEdD]. */
1309
1310   collect_exponent:
1311   if (*tokptr == '+' || *tokptr == '-')
1312     {
1313       *copy++ = *tokptr++;
1314     }
1315
1316   /* Now copy an exponent into the conversion buffer.  Note that at the
1317      moment underscores are *not* allowed in exponents. */
1318
1319   while (isdigit (*tokptr))
1320     {
1321       *copy++ = *tokptr++;
1322     }
1323
1324   /* If we transfered any chars to the conversion buffer, try to interpret its
1325      contents as a floating point value.  If any characters remain, then we
1326      must not have a valid floating point string. */
1327
1328   convert_float:
1329   *copy = '\0';
1330   if (copy != buf)
1331       {
1332         dval = strtod (buf, &copy);
1333         if (*copy == '\0')
1334           {
1335             yylval.dval = dval;
1336             lexptr = tokptr;
1337             return (FLOAT_LITERAL);
1338           }
1339       }
1340   return (0);
1341 }
1342
1343 /* Recognize a string literal.  A string literal is a sequence
1344    of characters enclosed in matching single or double quotes, except that
1345    a single character inside single quotes is a character literal, which
1346    we reject as a string literal.  To embed the terminator character inside
1347    a string, it is simply doubled (I.E. "this""is""one""string") */
1348
1349 static int
1350 match_string_literal ()
1351 {
1352   char *tokptr = lexptr;
1353
1354   for (tempbufindex = 0, tokptr++; *tokptr != '\0'; tokptr++)
1355     {
1356       CHECKBUF (1);
1357       if (*tokptr == *lexptr)
1358         {
1359           if (*(tokptr + 1) == *lexptr)
1360             {
1361               tokptr++;
1362             }
1363           else
1364             {
1365               break;
1366             }
1367         }
1368       tempbuf[tempbufindex++] = *tokptr;
1369     }
1370   if (*tokptr == '\0'                                   /* no terminator */
1371       || (tempbufindex == 1 && *tokptr == '\''))        /* char literal */
1372     {
1373       return (0);
1374     }
1375   else
1376     {
1377       tempbuf[tempbufindex] = '\0';
1378       yylval.sval.ptr = tempbuf;
1379       yylval.sval.length = tempbufindex;
1380       lexptr = ++tokptr;
1381       return (CHARACTER_STRING_LITERAL);
1382     }
1383 }
1384
1385 /* Recognize a character literal.  A character literal is single character
1386    or a control sequence, enclosed in single quotes.  A control sequence
1387    is a comma separated list of one or more integer literals, enclosed
1388    in parenthesis and introduced with a circumflex character.
1389
1390    EX:  'a'  '^(7)'  '^(7,8)'
1391
1392    As a GNU chill extension, the syntax C'xx' is also recognized as a
1393    character literal, where xx is a hex value for the character.
1394
1395    Note that more than a single character, enclosed in single quotes, is
1396    a string literal.
1397
1398    Also note that the control sequence form is not in GNU Chill since it
1399    is ambiguous with the string literal form using single quotes.  I.E.
1400    is '^(7)' a character literal or a string literal.  In theory it it
1401    possible to tell by context, but GNU Chill doesn't accept the control
1402    sequence form, so neither do we (for now the code is disabled).
1403
1404    Returns CHARACTER_LITERAL if a match is found.
1405    */
1406
1407 static int
1408 match_character_literal ()
1409 {
1410   char *tokptr = lexptr;
1411   int ival = 0;
1412
1413   if ((*tokptr == 'c' || *tokptr == 'C') && (*(tokptr + 1) == '\''))
1414     {
1415       /* We have a GNU chill extension form, so skip the leading "C'",
1416          decode the hex value, and then ensure that we have a trailing
1417          single quote character. */
1418       tokptr += 2;
1419       if (!decode_integer_value (16, &tokptr, &ival) || (*tokptr != '\''))
1420         {
1421           return (0);
1422         }
1423       tokptr++;
1424     }
1425   else if (*tokptr == '\'')
1426     {
1427       tokptr++;
1428
1429       /* Determine which form we have, either a control sequence or the
1430          single character form. */
1431
1432       if ((*tokptr == '^') && (*(tokptr + 1) == '('))
1433         {
1434 #if 0     /* Disable, see note above. -fnf */
1435           /* Match and decode a control sequence.  Return zero if we don't
1436              find a valid integer literal, or if the next unconsumed character
1437              after the integer literal is not the trailing ')'.
1438              FIXME:  We currently don't handle the multiple integer literal
1439              form. */
1440           tokptr += 2;
1441           if (!decode_integer_literal (&ival, &tokptr) || (*tokptr++ != ')'))
1442             {
1443               return (0);
1444             }
1445 #else
1446           return (0);
1447 #endif
1448         }
1449       else
1450         {
1451           ival = *tokptr++;
1452         }
1453
1454       /* The trailing quote has not yet been consumed.  If we don't find
1455          it, then we have no match. */
1456
1457       if (*tokptr++ != '\'')
1458         {
1459           return (0);
1460         }
1461     }
1462   else
1463     {
1464       /* Not a character literal. */
1465       return (0);
1466     }
1467   yylval.typed_val.val = ival;
1468   yylval.typed_val.type = builtin_type_chill_char;
1469   lexptr = tokptr;
1470   return (CHARACTER_LITERAL);
1471 }
1472
1473 /* Recognize an integer literal, as specified in Z.200 sec 5.2.4.2.
1474    Note that according to 5.2.4.2, a single "_" is also a valid integer
1475    literal, however GNU-chill requires there to be at least one "digit"
1476    in any integer literal. */
1477
1478 static int
1479 match_integer_literal ()
1480 {
1481   char *tokptr = lexptr;
1482   int ival;
1483
1484   if (!decode_integer_literal (&ival, &tokptr))
1485     {
1486       return (0);
1487     }
1488   else
1489     {
1490       yylval.typed_val.val = ival;
1491       yylval.typed_val.type = builtin_type_int;
1492       lexptr = tokptr;
1493       return (INTEGER_LITERAL);
1494     }
1495 }
1496
1497 /* Recognize a bit-string literal, as specified in Z.200 sec 5.2.4.8
1498    Note that according to 5.2.4.8, a single "_" is also a valid bit-string
1499    literal, however GNU-chill requires there to be at least one "digit"
1500    in any bit-string literal. */
1501
1502 static int
1503 match_bitstring_literal ()
1504 {
1505   register char *tokptr = lexptr;
1506   int bitoffset = 0;
1507   int bitcount = 0;
1508   int bits_per_char;
1509   int digit;
1510
1511   tempbufindex = 0;
1512   CHECKBUF (1);
1513   tempbuf[0] = 0;
1514
1515   /* Look for the required explicit base specifier. */
1516
1517   switch (*tokptr++)
1518     {
1519     case 'b':
1520     case 'B':
1521       bits_per_char = 1;
1522       break;
1523     case 'o':
1524     case 'O':
1525       bits_per_char = 3;
1526       break;
1527     case 'h':
1528     case 'H':
1529       bits_per_char = 4;
1530       break;
1531     default:
1532       return (0);
1533       break;
1534     }
1535
1536   /* Ensure that the character after the explicit base is a single quote. */
1537
1538   if (*tokptr++ != '\'')
1539     {
1540       return (0);
1541     }
1542
1543   while (*tokptr != '\0' && *tokptr != '\'')
1544     {
1545       digit = *tokptr;
1546       if (isupper (digit))
1547         digit = tolower (digit);
1548       tokptr++;
1549       switch (digit)
1550         {
1551           case '_':
1552             continue;
1553           case '0':  case '1':  case '2':  case '3':  case '4':
1554           case '5':  case '6':  case '7':  case '8':  case '9':
1555             digit -= '0';
1556             break;
1557           case 'a':  case 'b':  case 'c':  case 'd':  case 'e': case 'f':
1558             digit -= 'a';
1559             digit += 10;
1560             break;
1561           default:
1562             return (0);
1563             break;
1564         }
1565       if (digit >= 1 << bits_per_char)
1566         {
1567           /* Found something not in domain for current base. */
1568           return (0);
1569         }
1570       else
1571         {
1572           /* Extract bits from digit, packing them into the bitstring byte. */
1573           int k = TARGET_BYTE_ORDER == BIG_ENDIAN ? bits_per_char - 1 : 0;
1574           for (; TARGET_BYTE_ORDER == BIG_ENDIAN ? k >= 0 : k < bits_per_char;
1575                TARGET_BYTE_ORDER == BIG_ENDIAN ? k-- : k++)
1576             {
1577               bitcount++;
1578               if (digit & (1 << k))
1579                 {
1580                   tempbuf[tempbufindex] |=
1581                     (TARGET_BYTE_ORDER == BIG_ENDIAN)
1582                       ? (1 << (HOST_CHAR_BIT - 1 - bitoffset))
1583                         : (1 << bitoffset);
1584                 }
1585               bitoffset++;
1586               if (bitoffset == HOST_CHAR_BIT)
1587                 {
1588                   bitoffset = 0;
1589                   tempbufindex++;
1590                   CHECKBUF(1);
1591                   tempbuf[tempbufindex] = 0;
1592                 }
1593             }
1594         }
1595     }
1596
1597   /* Verify that we consumed everything up to the trailing single quote,
1598      and that we found some bits (IE not just underbars). */
1599
1600   if (*tokptr++ != '\'')
1601     {
1602       return (0);
1603     }
1604   else
1605     {
1606       yylval.sval.ptr = tempbuf;
1607       yylval.sval.length = bitcount;
1608       lexptr = tokptr;
1609       return (BIT_STRING_LITERAL);
1610     }
1611 }
1612
1613 /* Recognize tokens that start with '$'.  These include:
1614
1615         $regname        A native register name or a "standard
1616                         register name".
1617                         Return token GDB_REGNAME.
1618
1619         $variable       A convenience variable with a name chosen
1620                         by the user.
1621                         Return token GDB_VARIABLE.
1622
1623         $digits         Value history with index <digits>, starting
1624                         from the first value which has index 1.
1625                         Return GDB_LAST.
1626
1627         $$digits        Value history with index <digits> relative
1628                         to the last value.  I.E. $$0 is the last
1629                         value, $$1 is the one previous to that, $$2
1630                         is the one previous to $$1, etc.
1631                         Return token GDB_LAST.
1632
1633         $ | $0 | $$0    The last value in the value history.
1634                         Return token GDB_LAST.
1635
1636         $$              An abbreviation for the second to the last
1637                         value in the value history, I.E. $$1
1638                         Return token GDB_LAST.
1639
1640     Note that we currently assume that register names and convenience
1641     variables follow the convention of starting with a letter or '_'.
1642
1643    */
1644
1645 static int
1646 match_dollar_tokens ()
1647 {
1648   char *tokptr;
1649   int regno;
1650   int namelength;
1651   int negate;
1652   int ival;
1653
1654   /* We will always have a successful match, even if it is just for
1655      a single '$', the abbreviation for $$0.  So advance lexptr. */
1656
1657   tokptr = ++lexptr;
1658
1659   if (*tokptr == '_' || isalpha (*tokptr))
1660     {
1661       /* Look for a match with a native register name, usually something
1662          like "r0" for example. */
1663
1664       for (regno = 0; regno < NUM_REGS; regno++)
1665         {
1666           namelength = strlen (reg_names[regno]);
1667           if (STREQN (tokptr, reg_names[regno], namelength)
1668               && !isalnum (tokptr[namelength]))
1669             {
1670               yylval.lval = regno;
1671               lexptr += namelength;
1672               return (GDB_REGNAME);
1673             }
1674         }
1675
1676       /* Look for a match with a standard register name, usually something
1677          like "pc", which gdb always recognizes as the program counter
1678          regardless of what the native register name is. */
1679
1680       for (regno = 0; regno < num_std_regs; regno++)
1681         {
1682           namelength = strlen (std_regs[regno].name);
1683           if (STREQN (tokptr, std_regs[regno].name, namelength)
1684               && !isalnum (tokptr[namelength]))
1685             {
1686               yylval.lval = std_regs[regno].regnum;
1687               lexptr += namelength;
1688               return (GDB_REGNAME);
1689             }
1690         }
1691
1692       /* Attempt to match against a convenience variable.  Note that
1693          this will always succeed, because if no variable of that name
1694          already exists, the lookup_internalvar will create one for us.
1695          Also note that both lexptr and tokptr currently point to the
1696          start of the input string we are trying to match, and that we
1697          have already tested the first character for non-numeric, so we
1698          don't have to treat it specially. */
1699
1700       while (*tokptr == '_' || isalnum (*tokptr))
1701         {
1702           tokptr++;
1703         }
1704       yylval.sval.ptr = lexptr;
1705       yylval.sval.length = tokptr - lexptr;
1706       yylval.ivar = lookup_internalvar (copy_name (yylval.sval));
1707       lexptr = tokptr;
1708       return (GDB_VARIABLE);
1709     }
1710
1711   /* Since we didn't match against a register name or convenience
1712      variable, our only choice left is a history value. */
1713
1714   if (*tokptr == '$')
1715     {
1716       negate = 1;
1717       ival = 1;
1718       tokptr++;
1719     }
1720   else
1721     {
1722       negate = 0;
1723       ival = 0;
1724     }
1725
1726   /* Attempt to decode more characters as an integer value giving
1727      the index in the history list.  If successful, the value will
1728      overwrite ival (currently 0 or 1), and if not, ival will be
1729      left alone, which is good since it is currently correct for
1730      the '$' or '$$' case. */
1731
1732   decode_integer_literal (&ival, &tokptr);
1733   yylval.lval = negate ? -ival : ival;
1734   lexptr = tokptr;
1735   return (GDB_LAST);
1736 }
1737
1738 struct token
1739 {
1740   char *operator;
1741   int token;
1742 };
1743
1744 static const struct token idtokentab[] =
1745 {
1746     { "array", ARRAY },
1747     { "length", LENGTH },
1748     { "lower", LOWER },
1749     { "upper", UPPER },
1750     { "andif", ANDIF },
1751     { "pred", PRED },
1752     { "succ", SUCC },
1753     { "card", CARD },
1754     { "size", SIZE },
1755     { "orif", ORIF },
1756     { "num", NUM },
1757     { "abs", ABS },
1758     { "max", MAX_TOKEN },
1759     { "min", MIN_TOKEN },
1760     { "mod", MOD },
1761     { "rem", REM },
1762     { "not", NOT },
1763     { "xor", LOGXOR },
1764     { "and", LOGAND },
1765     { "in", IN },
1766     { "or", LOGIOR },
1767     { "up", UP },
1768     { "null", EMPTINESS_LITERAL }
1769 };
1770
1771 static const struct token tokentab2[] =
1772 {
1773     { ":=", GDB_ASSIGNMENT },
1774     { "//", SLASH_SLASH },
1775     { "->", POINTER },
1776     { "/=", NOTEQUAL },
1777     { "<=", LEQ },
1778     { ">=", GTR }
1779 };
1780
1781 /* Read one token, getting characters through lexptr.  */
1782 /* This is where we will check to make sure that the language and the
1783    operators used are compatible.  */
1784
1785 static int
1786 yylex ()
1787 {
1788     unsigned int i;
1789     int token;
1790     char *inputname;
1791     struct symbol *sym;
1792
1793     /* Skip over any leading whitespace. */
1794     while (isspace (*lexptr))
1795         {
1796             lexptr++;
1797         }
1798     /* Look for special single character cases which can't be the first
1799        character of some other multicharacter token. */
1800     switch (*lexptr)
1801         {
1802             case '\0':
1803                 return (0);
1804             case ',':
1805             case '=':
1806             case ';':
1807             case '!':
1808             case '+':
1809             case '*':
1810             case '(':
1811             case ')':
1812             case '[':
1813             case ']':
1814                 return (*lexptr++);
1815         }
1816     /* Look for characters which start a particular kind of multicharacter
1817        token, such as a character literal, register name, convenience
1818        variable name, string literal, etc. */
1819     switch (*lexptr)
1820       {
1821         case '\'':
1822         case '\"':
1823           /* First try to match a string literal, which is any
1824              sequence of characters enclosed in matching single or double
1825              quotes, except that a single character inside single quotes
1826              is a character literal, so we have to catch that case also. */
1827           token = match_string_literal ();
1828           if (token != 0)
1829             {
1830               return (token);
1831             }
1832           if (*lexptr == '\'')
1833             {
1834               token = match_character_literal ();
1835               if (token != 0)
1836                 {
1837                   return (token);
1838                 }
1839             }
1840           break;
1841         case 'C':
1842         case 'c':
1843           token = match_character_literal ();
1844           if (token != 0)
1845             {
1846               return (token);
1847             }
1848           break;
1849         case '$':
1850           token = match_dollar_tokens ();
1851           if (token != 0)
1852             {
1853               return (token);
1854             }
1855           break;
1856       }
1857     /* See if it is a special token of length 2.  */
1858     for (i = 0; i < sizeof (tokentab2) / sizeof (tokentab2[0]); i++)
1859         {
1860             if (STREQN (lexptr, tokentab2[i].operator, 2))
1861                 {
1862                     lexptr += 2;
1863                     return (tokentab2[i].token);
1864                 }
1865         }
1866     /* Look for single character cases which which could be the first
1867        character of some other multicharacter token, but aren't, or we
1868        would already have found it. */
1869     switch (*lexptr)
1870         {
1871             case '-':
1872             case ':':
1873             case '/':
1874             case '<':
1875             case '>':
1876                 return (*lexptr++);
1877         }
1878     /* Look for a float literal before looking for an integer literal, so
1879        we match as much of the input stream as possible. */
1880     token = match_float_literal ();
1881     if (token != 0)
1882         {
1883             return (token);
1884         }
1885     token = match_bitstring_literal ();
1886     if (token != 0)
1887         {
1888             return (token);
1889         }
1890     token = match_integer_literal ();
1891     if (token != 0)
1892         {
1893             return (token);
1894         }
1895
1896     /* Try to match a simple name string, and if a match is found, then
1897        further classify what sort of name it is and return an appropriate
1898        token.  Note that attempting to match a simple name string consumes
1899        the token from lexptr, so we can't back out if we later find that
1900        we can't classify what sort of name it is. */
1901
1902     inputname = match_simple_name_string ();
1903
1904     if (inputname != NULL)
1905       {
1906         char *simplename = (char*) alloca (strlen (inputname) + 1);
1907
1908         char *dptr = simplename, *sptr = inputname;
1909         for (; *sptr; sptr++)
1910           *dptr++ = isupper (*sptr) ? tolower(*sptr) : *sptr;
1911         *dptr = '\0';
1912
1913         /* See if it is a reserved identifier. */
1914         for (i = 0; i < sizeof (idtokentab) / sizeof (idtokentab[0]); i++)
1915             {
1916                 if (STREQ (simplename, idtokentab[i].operator))
1917                     {
1918                         return (idtokentab[i].token);
1919                     }
1920             }
1921
1922         /* Look for other special tokens. */
1923         if (STREQ (simplename, "true"))
1924             {
1925                 yylval.ulval = 1;
1926                 return (BOOLEAN_LITERAL);
1927             }
1928         if (STREQ (simplename, "false"))
1929             {
1930                 yylval.ulval = 0;
1931                 return (BOOLEAN_LITERAL);
1932             }
1933
1934         sym = lookup_symbol (inputname, expression_context_block,
1935                              VAR_NAMESPACE, (int *) NULL,
1936                              (struct symtab **) NULL);
1937         if (sym == NULL && strcmp (inputname, simplename) != 0)
1938           {
1939             sym = lookup_symbol (simplename, expression_context_block,
1940                                  VAR_NAMESPACE, (int *) NULL,
1941                                  (struct symtab **) NULL);
1942           }
1943         if (sym != NULL)
1944           {
1945             yylval.ssym.stoken.ptr = NULL;
1946             yylval.ssym.stoken.length = 0;
1947             yylval.ssym.sym = sym;
1948             yylval.ssym.is_a_field_of_this = 0; /* FIXME, C++'ism */
1949             switch (SYMBOL_CLASS (sym))
1950               {
1951               case LOC_BLOCK:
1952                 /* Found a procedure name. */
1953                 return (GENERAL_PROCEDURE_NAME);
1954               case LOC_STATIC:
1955                 /* Found a global or local static variable. */
1956                 return (LOCATION_NAME);
1957               case LOC_REGISTER:
1958               case LOC_ARG:
1959               case LOC_REF_ARG:
1960               case LOC_REGPARM:
1961               case LOC_REGPARM_ADDR:
1962               case LOC_LOCAL:
1963               case LOC_LOCAL_ARG:
1964               case LOC_BASEREG:
1965               case LOC_BASEREG_ARG:
1966                 if (innermost_block == NULL
1967                     || contained_in (block_found, innermost_block))
1968                   {
1969                     innermost_block = block_found;
1970                   }
1971                 return (LOCATION_NAME);
1972                 break;
1973               case LOC_CONST:
1974               case LOC_LABEL:
1975                 return (LOCATION_NAME);
1976                 break;
1977               case LOC_TYPEDEF:
1978                 yylval.tsym.type = SYMBOL_TYPE (sym);
1979                 return TYPENAME;
1980               case LOC_UNDEF:
1981               case LOC_CONST_BYTES:
1982               case LOC_OPTIMIZED_OUT:
1983                 error ("Symbol \"%s\" names no location.", inputname);
1984                 break;
1985               }
1986           }
1987         else if (!have_full_symbols () && !have_partial_symbols ())
1988           {
1989             error ("No symbol table is loaded.  Use the \"file\" command.");
1990           }
1991         else
1992           {
1993             error ("No symbol \"%s\" in current context.", inputname);
1994           }
1995       }
1996
1997     /* Catch single character tokens which are not part of some
1998        longer token. */
1999
2000     switch (*lexptr)
2001       {
2002         case '.':                       /* Not float for example. */
2003           lexptr++;
2004           while (isspace (*lexptr)) lexptr++;
2005           inputname = match_simple_name_string ();
2006           if (!inputname)
2007             return '.';
2008           return FIELD_NAME;
2009       }
2010
2011     return (ILLEGAL_TOKEN);
2012 }
2013
2014 void
2015 yyerror (msg)
2016      char *msg;
2017 {
2018   error ("A %s in expression, near `%s'.", (msg ? msg : "error"), lexptr);
2019 }