gdb/jv-exp.y

   1 /* YACC parser for Java expressions, for GDB.
   2    Copyright (C) 1997.
   3    Free Software Foundation, Inc.
   4
   5 This file is part of GDB.
   6
   7 This program is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 2 of the License, or
  10 (at your option) any later version.
  11
  12 This program is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with this program; if not, write to the Free Software
  19 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  20
  21 /* Parse a Java expression from text in a string,
  22    and return the result as a  struct expression  pointer.
  23    That structure contains arithmetic operations in reverse polish,
  24    with constants represented by operations that are followed by special data.
  25    See expression.h for the details of the format.
  26    What is important here is that it can be built up sequentially
  27    during the process of parsing; the lower levels of the tree always
  28    come first in the result.  Well, almost always; see ArrayAccess.
  29
  30    Note that malloc's and realloc's in this file are transformed to
  31    xmalloc and xrealloc respectively by the same sed command in the
  32    makefile that remaps any other malloc/realloc inserted by the parser
  33    generator.  Doing this with #defines and trying to control the interaction
  34    with include files (<malloc.h> and <stdlib.h> for example) just became
  35    too messy, particularly when such includes can be inserted at random
  36    times by the parser generator.  */
  37
  38 %{
  39
  40 #include "defs.h"
  41 #include "gdb_string.h"
  42 #include <ctype.h>
  43 #include "expression.h"
  44 #include "value.h"
  45 #include "parser-defs.h"
  46 #include "language.h"
  47 #include "jv-lang.h"
  48 #include "bfd.h" /* Required by objfiles.h.  */
  49 #include "symfile.h" /* Required by objfiles.h.  */
  50 #include "objfiles.h" /* For have_full_symbols and have_partial_symbols */
  51
  52 /* Remap normal yacc parser interface names (yyparse, yylex, yyerror, etc),
  53    as well as gratuitiously global symbol names, so we can have multiple
  54    yacc generated parsers in gdb.  Note that these are only the variables
  55    produced by yacc.  If other parser generators (bison, byacc, etc) produce
  56    additional global names that conflict at link time, then those parser
  57    generators need to be fixed instead of adding those names to this list. */
  58
  59 #define yymaxdepth java_maxdepth
  60 #define yyparse java_parse
  61 #define yylex   java_lex
  62 #define yyerror java_error
  63 #define yylval  java_lval
  64 #define yychar  java_char
  65 #define yydebug java_debug
  66 #define yypact  java_pact
  67 #define yyr1    java_r1
  68 #define yyr2    java_r2
  69 #define yydef   java_def
  70 #define yychk   java_chk
  71 #define yypgo   java_pgo
  72 #define yyact   java_act
  73 #define yyexca  java_exca
  74 #define yyerrflag java_errflag
  75 #define yynerrs java_nerrs
  76 #define yyps    java_ps
  77 #define yypv    java_pv
  78 #define yys     java_s
  79 #define yy_yys  java_yys
  80 #define yystate java_state
  81 #define yytmp   java_tmp
  82 #define yyv     java_v
  83 #define yy_yyv  java_yyv
  84 #define yyval   java_val
  85 #define yylloc  java_lloc
  86 #define yyreds  java_reds               /* With YYDEBUG defined */
  87 #define yytoks  java_toks               /* With YYDEBUG defined */
  88 #define yylhs   java_yylhs
  89 #define yylen   java_yylen
  90 #define yydefred java_yydefred
  91 #define yydgoto java_yydgoto
  92 #define yysindex java_yysindex
  93 #define yyrindex java_yyrindex
  94 #define yygindex java_yygindex
  95 #define yytable  java_yytable
  96 #define yycheck  java_yycheck
  97
  98 #ifndef YYDEBUG
  99 #define YYDEBUG 0               /* Default to no yydebug support */
 100 #endif
 101
 102 int
 103 yyparse PARAMS ((void));
 104
 105 static int
 106 yylex PARAMS ((void));
 107
 108 void
 109 yyerror PARAMS ((char *));
 110
 111 static struct type * java_type_from_name PARAMS ((struct stoken));
 112 static void push_expression_name PARAMS ((struct stoken));
 113 static void push_fieldnames PARAMS ((struct stoken));
 114
 115 static struct expression *copy_exp PARAMS ((struct expression *, int));
 116 static void insert_exp PARAMS ((int, struct expression *));
 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     struct {
 128       LONGEST val;
 129       struct type *type;
 130     } typed_val_int;
 131     struct {
 132       DOUBLEST dval;
 133       struct type *type;
 134     } typed_val_float;
 135     struct symbol *sym;
 136     struct type *tval;
 137     struct stoken sval;
 138     struct ttype tsym;
 139     struct symtoken ssym;
 140     struct block *bval;
 141     enum exp_opcode opcode;
 142     struct internalvar *ivar;
 143     int *ivec;
 144   }
 145
 146 %{
 147 /* YYSTYPE gets defined by %union */
 148 static int
 149 parse_number PARAMS ((char *, int, int, YYSTYPE *));
 150 %}
 151
 152 %type <lval> rcurly Dims Dims_opt
 153 %type <tval> ClassOrInterfaceType ClassType /* ReferenceType Type ArrayType */
 154 %type <tval> IntegralType FloatingPointType NumericType PrimitiveType ArrayType PrimitiveOrArrayType
 155
 156 %token <typed_val_int> INTEGER_LITERAL
 157 %token <typed_val_float> FLOATING_POINT_LITERAL
 158
 159 %token <sval> IDENTIFIER
 160 %token <sval> STRING_LITERAL
 161 %token <lval> BOOLEAN_LITERAL
 162 %token <tsym> TYPENAME
 163 %type <sval> Name SimpleName QualifiedName ForcedName
 164
 165 /* A NAME_OR_INT is a symbol which is not known in the symbol table,
 166    but which would parse as a valid number in the current input radix.
 167    E.g. "c" when input_radix==16.  Depending on the parse, it will be
 168    turned into a name or into a number.  */
 169
 170 %token <sval> NAME_OR_INT
 171
 172 %token ERROR
 173
 174 /* Special type cases, put in to allow the parser to distinguish different
 175    legal basetypes.  */
 176 %token LONG SHORT BYTE INT CHAR BOOLEAN DOUBLE FLOAT
 177
 178 %token VARIABLE
 179
 180 %token <opcode> ASSIGN_MODIFY
 181
 182 %token THIS SUPER NEW
 183
 184 %left ','
 185 %right '=' ASSIGN_MODIFY
 186 %right '?'
 187 %left OROR
 188 %left ANDAND
 189 %left '|'
 190 %left '^'
 191 %left '&'
 192 %left EQUAL NOTEQUAL
 193 %left '<' '>' LEQ GEQ
 194 %left LSH RSH
 195 %left '+' '-'
 196 %left '*' '/' '%'
 197 %right INCREMENT DECREMENT
 198 %right '.' '[' '('
 199
 200 \f
 201 %%
 202
 203 start   :       exp1
 204         |       type_exp
 205         ;
 206
 207 type_exp:       PrimitiveOrArrayType
 208                 {
 209                   write_exp_elt_opcode(OP_TYPE);
 210                   write_exp_elt_type($1);
 211                   write_exp_elt_opcode(OP_TYPE);
 212                 }
 213         ;
 214
 215 PrimitiveOrArrayType:
 216                 PrimitiveType
 217         |       ArrayType
 218         ;
 219
 220 StringLiteral:
 221         STRING_LITERAL
 222                 {
 223                   write_exp_elt_opcode (OP_STRING);
 224                   write_exp_string ($1);
 225                   write_exp_elt_opcode (OP_STRING);
 226                 }
 227 ;
 228
 229 Literal:
 230         INTEGER_LITERAL
 231                 { write_exp_elt_opcode (OP_LONG);
 232                   write_exp_elt_type ($1.type);
 233                   write_exp_elt_longcst ((LONGEST)($1.val));
 234                   write_exp_elt_opcode (OP_LONG); }
 235 |       NAME_OR_INT
 236                 { YYSTYPE val;
 237                   parse_number ($1.ptr, $1.length, 0, &val);
 238                   write_exp_elt_opcode (OP_LONG);
 239                   write_exp_elt_type (val.typed_val_int.type);
 240                   write_exp_elt_longcst ((LONGEST)val.typed_val_int.val);
 241                   write_exp_elt_opcode (OP_LONG);
 242                 }
 243 |       FLOATING_POINT_LITERAL
 244                 { write_exp_elt_opcode (OP_DOUBLE);
 245                   write_exp_elt_type ($1.type);
 246                   write_exp_elt_dblcst ($1.dval);
 247                   write_exp_elt_opcode (OP_DOUBLE); }
 248 |       BOOLEAN_LITERAL
 249                 { write_exp_elt_opcode (OP_LONG);
 250                   write_exp_elt_type (java_boolean_type);
 251                   write_exp_elt_longcst ((LONGEST)$1);
 252                   write_exp_elt_opcode (OP_LONG); }
 253 |       StringLiteral
 254         ;
 255
 256 /* UNUSED:
 257 Type:
 258         PrimitiveType
 259 |       ReferenceType
 260 ;
 261 */
 262
 263 PrimitiveType:
 264         NumericType
 265 |       BOOLEAN
 266                 { $$ = java_boolean_type; }
 267 ;
 268
 269 NumericType:
 270         IntegralType
 271 |       FloatingPointType
 272 ;
 273
 274 IntegralType:
 275         BYTE
 276                 { $$ = java_byte_type; }
 277 |       SHORT
 278                 { $$ = java_short_type; }
 279 |       INT
 280                 { $$ = java_int_type; }
 281 |       LONG
 282                 { $$ = java_long_type; }
 283 |       CHAR
 284                 { $$ = java_char_type; }
 285 ;
 286
 287 FloatingPointType:
 288         FLOAT
 289                 { $$ = java_float_type; }
 290 |       DOUBLE
 291                 { $$ = java_double_type; }
 292 ;
 293
 294 /* UNUSED:
 295 ReferenceType:
 296         ClassOrInterfaceType
 297 |       ArrayType
 298 ;
 299 */
 300
 301 ClassOrInterfaceType:
 302         Name
 303                 { $$ = java_type_from_name ($1); }
 304 ;
 305
 306 ClassType:
 307         ClassOrInterfaceType
 308 ;
 309
 310 ArrayType:
 311         PrimitiveType Dims
 312                 { $$ = java_array_type ($1, $2); }
 313 |       Name Dims
 314                 { $$ = java_array_type (java_type_from_name ($1), $2); }
 315 ;
 316
 317 Name:
 318         IDENTIFIER
 319 |       QualifiedName
 320 ;
 321
 322 ForcedName:
 323         SimpleName
 324 |       QualifiedName
 325 ;
 326
 327 SimpleName:
 328         IDENTIFIER
 329 |       NAME_OR_INT
 330 ;
 331
 332 QualifiedName:
 333         Name '.' SimpleName
 334                 { $$.length = $1.length + $3.length + 1;
 335                   if ($1.ptr + $1.length + 1 == $3.ptr
 336                       && $1.ptr[$1.length] == '.')
 337                     $$.ptr = $1.ptr;  /* Optimization. */
 338                   else
 339                     {
 340                       $$.ptr = (char *) malloc ($$.length + 1);
 341                       make_cleanup (free, $$.ptr);
 342                       sprintf ($$.ptr, "%.*s.%.*s",
 343                                $1.length, $1.ptr, $3.length, $3.ptr);
 344                 } }
 345 ;
 346
 347 /*
 348 type_exp:       type
 349                         { write_exp_elt_opcode(OP_TYPE);
 350                           write_exp_elt_type($1);
 351                           write_exp_elt_opcode(OP_TYPE);}
 352         ;
 353         */
 354
 355 /* Expressions, including the comma operator.  */
 356 exp1    :       Expression
 357         |       exp1 ',' Expression
 358                         { write_exp_elt_opcode (BINOP_COMMA); }
 359         ;
 360
 361 Primary:
 362         PrimaryNoNewArray
 363 |       ArrayCreationExpression
 364 ;
 365
 366 PrimaryNoNewArray:
 367         Literal
 368 |       THIS
 369                 { write_exp_elt_opcode (OP_THIS);
 370                   write_exp_elt_opcode (OP_THIS); }
 371 |       '(' Expression ')'
 372 |       ClassInstanceCreationExpression
 373 |       FieldAccess
 374 |       MethodInvocation
 375 |       ArrayAccess
 376 |       lcurly ArgumentList rcurly
 377                 { write_exp_elt_opcode (OP_ARRAY);
 378                   write_exp_elt_longcst ((LONGEST) 0);
 379                   write_exp_elt_longcst ((LONGEST) $3);
 380                   write_exp_elt_opcode (OP_ARRAY); }
 381 ;
 382
 383 lcurly:
 384         '{'
 385                 { start_arglist (); }
 386 ;
 387
 388 rcurly:
 389         '}'
 390                 { $$ = end_arglist () - 1; }
 391 ;
 392
 393 ClassInstanceCreationExpression:
 394         NEW ClassType '(' ArgumentList_opt ')'
 395                 { error ("FIXME - ClassInstanceCreationExpression"); }
 396 ;
 397
 398 ArgumentList:
 399         Expression
 400                 { arglist_len = 1; }
 401 |       ArgumentList ',' Expression
 402                 { arglist_len++; }
 403 ;
 404
 405 ArgumentList_opt:
 406         /* EMPTY */
 407                 { arglist_len = 0; }
 408 | ArgumentList
 409 ;
 410
 411 ArrayCreationExpression:
 412         NEW PrimitiveType DimExprs Dims_opt
 413                 { error ("FIXME - ArrayCreatiionExpression"); }
 414 |       NEW ClassOrInterfaceType DimExprs Dims_opt
 415                 { error ("FIXME - ArrayCreatiionExpression"); }
 416 ;
 417
 418 DimExprs:
 419         DimExpr
 420 |       DimExprs DimExpr
 421 ;
 422
 423 DimExpr:
 424         '[' Expression ']'
 425 ;
 426
 427 Dims:
 428         '[' ']'
 429                 { $$ = 1; }
 430 |       Dims '[' ']'
 431         { $$ = $1 + 1; }
 432 ;
 433
 434 Dims_opt:
 435         Dims
 436 |       /* EMPTY */
 437                 { $$ = 0; }
 438 ;
 439
 440 FieldAccess:
 441         Primary '.' SimpleName
 442                 { push_fieldnames ($3); }
 443 |       VARIABLE '.' SimpleName
 444                 { push_fieldnames ($3); }
 445 /*|     SUPER '.' SimpleName { FIXME } */
 446 ;
 447
 448 MethodInvocation:
 449         Name '(' ArgumentList_opt ')'
 450                 { error ("method invocation not implemented"); }
 451 |       Primary '.' SimpleName '(' ArgumentList_opt ')'
 452                 { error ("method invocation not implemented"); }
 453 |       SUPER '.' SimpleName '(' ArgumentList_opt ')'
 454                 { error ("method invocation not implemented"); }
 455 ;
 456
 457 ArrayAccess:
 458         Name '[' Expression ']'
 459                 {
 460                   /* Emit code for the Name now, then exchange it in the
 461                      expout array with the Expression's code.  We could
 462                      introduce a OP_SWAP code or a reversed version of
 463                      BINOP_SUBSCRIPT, but that makes the rest of GDB pay
 464                      for our parsing kludges.  */
 465                   struct expression *name_expr;
 466
 467                   push_expression_name ($1);
 468                   name_expr = copy_exp (expout, expout_ptr);
 469                   expout_ptr -= name_expr->nelts;
 470                   insert_exp (expout_ptr-length_of_subexp (expout, expout_ptr),
 471                               name_expr);
 472                   free (name_expr);
 473                   write_exp_elt_opcode (BINOP_SUBSCRIPT);
 474                 }
 475 |       VARIABLE '[' Expression ']'
 476                 { write_exp_elt_opcode (BINOP_SUBSCRIPT); }
 477 |       PrimaryNoNewArray '[' Expression ']'
 478                 { write_exp_elt_opcode (BINOP_SUBSCRIPT); }
 479 ;
 480
 481 PostfixExpression:
 482         Primary
 483 |       Name
 484                 { push_expression_name ($1); }
 485 |       VARIABLE
 486                 /* Already written by write_dollar_variable. */
 487 |       PostIncrementExpression
 488 |       PostDecrementExpression
 489 ;
 490
 491 PostIncrementExpression:
 492         PostfixExpression INCREMENT
 493                 { write_exp_elt_opcode (UNOP_POSTINCREMENT); }
 494 ;
 495
 496 PostDecrementExpression:
 497         PostfixExpression DECREMENT
 498                 { write_exp_elt_opcode (UNOP_POSTDECREMENT); }
 499 ;
 500
 501 UnaryExpression:
 502         PreIncrementExpression
 503 |       PreDecrementExpression
 504 |       '+' UnaryExpression
 505 |       '-' UnaryExpression
 506                 { write_exp_elt_opcode (UNOP_NEG); }
 507 |       '*' UnaryExpression
 508                 { write_exp_elt_opcode (UNOP_IND); } /*FIXME not in Java  */
 509 |       UnaryExpressionNotPlusMinus
 510 ;
 511
 512 PreIncrementExpression:
 513         INCREMENT UnaryExpression
 514                 { write_exp_elt_opcode (UNOP_PREINCREMENT); }
 515 ;
 516
 517 PreDecrementExpression:
 518         DECREMENT UnaryExpression
 519                 { write_exp_elt_opcode (UNOP_PREDECREMENT); }
 520 ;
 521
 522 UnaryExpressionNotPlusMinus:
 523         PostfixExpression
 524 |       '~' UnaryExpression
 525                 { write_exp_elt_opcode (UNOP_COMPLEMENT); }
 526 |       '!' UnaryExpression
 527                 { write_exp_elt_opcode (UNOP_LOGICAL_NOT); }
 528 |       CastExpression
 529         ;
 530
 531 CastExpression:
 532         '(' PrimitiveType Dims_opt ')' UnaryExpression
 533                 { write_exp_elt_opcode (UNOP_CAST);
 534                   write_exp_elt_type (java_array_type ($2, $3));
 535                   write_exp_elt_opcode (UNOP_CAST); }
 536 |       '(' Expression ')' UnaryExpressionNotPlusMinus
 537                 {
 538                   int exp_size = expout_ptr;
 539                   int last_exp_size = length_of_subexp(expout, expout_ptr);
 540                   struct type *type;
 541                   int i;
 542                   int base = expout_ptr - last_exp_size - 3;
 543                   if (base < 0 || expout->elts[base+2].opcode != OP_TYPE)
 544                     error ("invalid cast expression");
 545                   type = expout->elts[base+1].type;
 546                   /* Remove the 'Expression' and slide the
 547                      UnaryExpressionNotPlusMinus down to replace it. */
 548                   for (i = 0;  i < last_exp_size;  i++)
 549                     expout->elts[base + i] = expout->elts[base + i + 3];
 550                   expout_ptr -= 3;
 551                   if (TYPE_CODE (type) == TYPE_CODE_STRUCT)
 552                     type = lookup_pointer_type (type);
 553                   write_exp_elt_opcode (UNOP_CAST);
 554                   write_exp_elt_type (type);
 555                   write_exp_elt_opcode (UNOP_CAST);
 556                 }
 557 |       '(' Name Dims ')' UnaryExpressionNotPlusMinus
 558                 { write_exp_elt_opcode (UNOP_CAST);
 559                   write_exp_elt_type (java_array_type (java_type_from_name ($2), $3));
 560                   write_exp_elt_opcode (UNOP_CAST); }
 561 ;
 562
 563
 564 MultiplicativeExpression:
 565         UnaryExpression
 566 |       MultiplicativeExpression '*' UnaryExpression
 567                 { write_exp_elt_opcode (BINOP_MUL); }
 568 |       MultiplicativeExpression '/' UnaryExpression
 569                 { write_exp_elt_opcode (BINOP_DIV); }
 570 |       MultiplicativeExpression '%' UnaryExpression
 571                 { write_exp_elt_opcode (BINOP_REM); }
 572 ;
 573
 574 AdditiveExpression:
 575         MultiplicativeExpression
 576 |       AdditiveExpression '+' MultiplicativeExpression
 577                 { write_exp_elt_opcode (BINOP_ADD); }
 578 |       AdditiveExpression '-' MultiplicativeExpression
 579                 { write_exp_elt_opcode (BINOP_SUB); }
 580 ;
 581
 582 ShiftExpression:
 583         AdditiveExpression
 584 |       ShiftExpression LSH AdditiveExpression
 585                 { write_exp_elt_opcode (BINOP_LSH); }
 586 |       ShiftExpression RSH AdditiveExpression
 587                 { write_exp_elt_opcode (BINOP_RSH); }
 588 /* |    ShiftExpression >>> AdditiveExpression { FIXME } */
 589 ;
 590
 591 RelationalExpression:
 592         ShiftExpression
 593 |       RelationalExpression '<' ShiftExpression
 594                 { write_exp_elt_opcode (BINOP_LESS); }
 595 |       RelationalExpression '>' ShiftExpression
 596                 { write_exp_elt_opcode (BINOP_GTR); }
 597 |       RelationalExpression LEQ ShiftExpression
 598                 { write_exp_elt_opcode (BINOP_LEQ); }
 599 |       RelationalExpression GEQ ShiftExpression
 600                 { write_exp_elt_opcode (BINOP_GEQ); }
 601 /* | RelationalExpresion INSTANCEOF ReferenceType { FIXME } */
 602 ;
 603
 604 EqualityExpression:
 605         RelationalExpression
 606 |       EqualityExpression EQUAL RelationalExpression
 607                 { write_exp_elt_opcode (BINOP_EQUAL); }
 608 |       EqualityExpression NOTEQUAL RelationalExpression
 609                 { write_exp_elt_opcode (BINOP_NOTEQUAL); }
 610 ;
 611
 612 AndExpression:
 613         EqualityExpression
 614 |       AndExpression '&' EqualityExpression
 615                 { write_exp_elt_opcode (BINOP_BITWISE_AND); }
 616 ;
 617
 618 ExclusiveOrExpression:
 619         AndExpression
 620 |       ExclusiveOrExpression '^' AndExpression
 621                 { write_exp_elt_opcode (BINOP_BITWISE_XOR); }
 622 ;
 623 InclusiveOrExpression:
 624         ExclusiveOrExpression
 625 |       InclusiveOrExpression '|' ExclusiveOrExpression
 626                 { write_exp_elt_opcode (BINOP_BITWISE_IOR); }
 627 ;
 628
 629 ConditionalAndExpression:
 630         InclusiveOrExpression
 631 |       ConditionalAndExpression ANDAND InclusiveOrExpression
 632                 { write_exp_elt_opcode (BINOP_LOGICAL_AND); }
 633 ;
 634
 635 ConditionalOrExpression:
 636         ConditionalAndExpression
 637 |       ConditionalOrExpression OROR ConditionalAndExpression
 638                 { write_exp_elt_opcode (BINOP_LOGICAL_OR); }
 639 ;
 640
 641 ConditionalExpression:
 642         ConditionalOrExpression
 643 |       ConditionalOrExpression '?' Expression ':' ConditionalExpression
 644                 { write_exp_elt_opcode (TERNOP_COND); }
 645 ;
 646
 647 AssignmentExpression:
 648         ConditionalExpression
 649 |       Assignment
 650 ;
 651
 652 Assignment:
 653         LeftHandSide '=' ConditionalExpression
 654                 { write_exp_elt_opcode (BINOP_ASSIGN); }
 655 |       LeftHandSide ASSIGN_MODIFY ConditionalExpression
 656                 { write_exp_elt_opcode (BINOP_ASSIGN_MODIFY);
 657                   write_exp_elt_opcode ($2);
 658                   write_exp_elt_opcode (BINOP_ASSIGN_MODIFY); }
 659 ;
 660
 661 LeftHandSide:
 662         ForcedName
 663                 { push_expression_name ($1); }
 664 |       VARIABLE
 665                 /* Already written by write_dollar_variable. */
 666 |       FieldAccess
 667 |       ArrayAccess
 668 ;
 669
 670
 671 Expression:
 672         AssignmentExpression
 673 ;
 674
 675 %%
 676 /* Take care of parsing a number (anything that starts with a digit).
 677    Set yylval and return the token type; update lexptr.
 678    LEN is the number of characters in it.  */
 679
 680 /*** Needs some error checking for the float case ***/
 681
 682 static int
 683 parse_number (p, len, parsed_float, putithere)
 684      register char *p;
 685      register int len;
 686      int parsed_float;
 687      YYSTYPE *putithere;
 688 {
 689   register ULONGEST n = 0;
 690   ULONGEST limit, limit_div_base;
 691
 692   register int c;
 693   register int base = input_radix;
 694
 695   struct type *type;
 696
 697   if (parsed_float)
 698     {
 699       /* It's a float since it contains a point or an exponent.  */
 700       char c;
 701       int num = 0;      /* number of tokens scanned by scanf */
 702       char saved_char = p[len];
 703
 704       p[len] = 0;       /* null-terminate the token */
 705       if (sizeof (putithere->typed_val_float.dval) <= sizeof (float))
 706         num = sscanf (p, "%g%c", (float *) &putithere->typed_val_float.dval, &c);
 707       else if (sizeof (putithere->typed_val_float.dval) <= sizeof (double))
 708         num = sscanf (p, "%lg%c", (double *) &putithere->typed_val_float.dval, &c);
 709       else
 710         {
 711 #ifdef SCANF_HAS_LONG_DOUBLE
 712           num = sscanf (p, "%Lg%c", &putithere->typed_val_float.dval, &c);
 713 #else
 714           /* Scan it into a double, then assign it to the long double.
 715              This at least wins with values representable in the range
 716              of doubles. */
 717           double temp;
 718           num = sscanf (p, "%lg%c", &temp, &c);
 719           putithere->typed_val_float.dval = temp;
 720 #endif
 721         }
 722       p[len] = saved_char;      /* restore the input stream */
 723       if (num != 1)             /* check scanf found ONLY a float ... */
 724         return ERROR;
 725       /* See if it has `f' or `d' suffix (float or double).  */
 726
 727       c = tolower (p[len - 1]);
 728
 729       if (c == 'f' || c == 'F')
 730         putithere->typed_val_float.type = builtin_type_float;
 731       else if (isdigit (c) || c == '.' || c == 'd' || c == 'D')
 732         putithere->typed_val_float.type = builtin_type_double;
 733       else
 734         return ERROR;
 735
 736       return FLOATING_POINT_LITERAL;
 737     }
 738
 739   /* Handle base-switching prefixes 0x, 0t, 0d, 0 */
 740   if (p[0] == '0')
 741     switch (p[1])
 742       {
 743       case 'x':
 744       case 'X':
 745         if (len >= 3)
 746           {
 747             p += 2;
 748             base = 16;
 749             len -= 2;
 750           }
 751         break;
 752
 753       case 't':
 754       case 'T':
 755       case 'd':
 756       case 'D':
 757         if (len >= 3)
 758           {
 759             p += 2;
 760             base = 10;
 761             len -= 2;
 762           }
 763         break;
 764
 765       default:
 766         base = 8;
 767         break;
 768       }
 769
 770   c = p[len-1];
 771   limit = (ULONGEST)0xffffffff;
 772   if (c == 'l' || c == 'L')
 773     {
 774       type = java_long_type;
 775       len--;
 776       /* A paranoid calculation of (1<<64)-1. */
 777       limit = ((limit << 16) << 16) | limit;
 778     }
 779   else
 780     {
 781       type = java_int_type;
 782     }
 783   limit_div_base = limit / (ULONGEST) base;
 784
 785   while (--len >= 0)
 786     {
 787       c = *p++;
 788       if (c >= '0' && c <= '9')
 789         c -= '0';
 790       else if (c >= 'A' && c <= 'Z')
 791         c -= 'A' - 10;
 792       else if (c >= 'a' && c <= 'z')
 793         c -= 'a' - 10;
 794       else
 795         return ERROR;   /* Char not a digit */
 796       if (c >= base)
 797         return ERROR;
 798       if (n > limit_div_base
 799           || (n *= base) > limit - c)
 800         error ("Numeric constant too large.");
 801       n += c;
 802         }
 803
 804    putithere->typed_val_int.val = n;
 805    putithere->typed_val_int.type = type;
 806    return INTEGER_LITERAL;
 807 }
 808
 809 struct token
 810 {
 811   char *operator;
 812   int token;
 813   enum exp_opcode opcode;
 814 };
 815
 816 static const struct token tokentab3[] =
 817   {
 818     {">>=", ASSIGN_MODIFY, BINOP_RSH},
 819     {"<<=", ASSIGN_MODIFY, BINOP_LSH}
 820   };
 821
 822 static const struct token tokentab2[] =
 823   {
 824     {"+=", ASSIGN_MODIFY, BINOP_ADD},
 825     {"-=", ASSIGN_MODIFY, BINOP_SUB},
 826     {"*=", ASSIGN_MODIFY, BINOP_MUL},
 827     {"/=", ASSIGN_MODIFY, BINOP_DIV},
 828     {"%=", ASSIGN_MODIFY, BINOP_REM},
 829     {"|=", ASSIGN_MODIFY, BINOP_BITWISE_IOR},
 830     {"&=", ASSIGN_MODIFY, BINOP_BITWISE_AND},
 831     {"^=", ASSIGN_MODIFY, BINOP_BITWISE_XOR},
 832     {"++", INCREMENT, BINOP_END},
 833     {"--", DECREMENT, BINOP_END},
 834     {"&&", ANDAND, BINOP_END},
 835     {"||", OROR, BINOP_END},
 836     {"<<", LSH, BINOP_END},
 837     {">>", RSH, BINOP_END},
 838     {"==", EQUAL, BINOP_END},
 839     {"!=", NOTEQUAL, BINOP_END},
 840     {"<=", LEQ, BINOP_END},
 841     {">=", GEQ, BINOP_END}
 842   };
 843
 844 /* Read one token, getting characters through lexptr.  */
 845
 846 static int
 847 yylex ()
 848 {
 849   int c;
 850   int namelen;
 851   unsigned int i;
 852   char *tokstart;
 853   char *tokptr;
 854   int tempbufindex;
 855   static char *tempbuf;
 856   static int tempbufsize;
 857
 858  retry:
 859
 860   tokstart = lexptr;
 861   /* See if it is a special token of length 3.  */
 862   for (i = 0; i < sizeof tokentab3 / sizeof tokentab3[0]; i++)
 863     if (STREQN (tokstart, tokentab3[i].operator, 3))
 864       {
 865         lexptr += 3;
 866         yylval.opcode = tokentab3[i].opcode;
 867         return tokentab3[i].token;
 868       }
 869
 870   /* See if it is a special token of length 2.  */
 871   for (i = 0; i < sizeof tokentab2 / sizeof tokentab2[0]; i++)
 872     if (STREQN (tokstart, tokentab2[i].operator, 2))
 873       {
 874         lexptr += 2;
 875         yylval.opcode = tokentab2[i].opcode;
 876         return tokentab2[i].token;
 877       }
 878
 879   switch (c = *tokstart)
 880     {
 881     case 0:
 882       return 0;
 883
 884     case ' ':
 885     case '\t':
 886     case '\n':
 887       lexptr++;
 888       goto retry;
 889
 890     case '\'':
 891       /* We either have a character constant ('0' or '\177' for example)
 892          or we have a quoted symbol reference ('foo(int,int)' in C++
 893          for example). */
 894       lexptr++;
 895       c = *lexptr++;
 896       if (c == '\\')
 897         c = parse_escape (&lexptr);
 898       else if (c == '\'')
 899         error ("Empty character constant.");
 900
 901       yylval.typed_val_int.val = c;
 902       yylval.typed_val_int.type = builtin_type_char;
 903
 904       c = *lexptr++;
 905       if (c != '\'')
 906         {
 907           namelen = skip_quoted (tokstart) - tokstart;
 908           if (namelen > 2)
 909             {
 910               lexptr = tokstart + namelen;
 911               if (lexptr[-1] != '\'')
 912                 error ("Unmatched single quote.");
 913               namelen -= 2;
 914               tokstart++;
 915               goto tryname;
 916             }
 917           error ("Invalid character constant.");
 918         }
 919       return INTEGER_LITERAL;
 920
 921     case '(':
 922       paren_depth++;
 923       lexptr++;
 924       return c;
 925
 926     case ')':
 927       if (paren_depth == 0)
 928         return 0;
 929       paren_depth--;
 930       lexptr++;
 931       return c;
 932
 933     case ',':
 934       if (comma_terminates && paren_depth == 0)
 935         return 0;
 936       lexptr++;
 937       return c;
 938
 939     case '.':
 940       /* Might be a floating point number.  */
 941       if (lexptr[1] < '0' || lexptr[1] > '9')
 942         goto symbol;            /* Nope, must be a symbol. */
 943       /* FALL THRU into number case.  */
 944
 945     case '0':
 946     case '1':
 947     case '2':
 948     case '3':
 949     case '4':
 950     case '5':
 951     case '6':
 952     case '7':
 953     case '8':
 954     case '9':
 955       {
 956         /* It's a number.  */
 957         int got_dot = 0, got_e = 0, toktype;
 958         register char *p = tokstart;
 959         int hex = input_radix > 10;
 960
 961         if (c == '0' && (p[1] == 'x' || p[1] == 'X'))
 962           {
 963             p += 2;
 964             hex = 1;
 965           }
 966         else if (c == '0' && (p[1]=='t' || p[1]=='T' || p[1]=='d' || p[1]=='D'))
 967           {
 968             p += 2;
 969             hex = 0;
 970           }
 971
 972         for (;; ++p)
 973           {
 974             /* This test includes !hex because 'e' is a valid hex digit
 975                and thus does not indicate a floating point number when
 976                the radix is hex.  */
 977             if (!hex && !got_e && (*p == 'e' || *p == 'E'))
 978               got_dot = got_e = 1;
 979             /* This test does not include !hex, because a '.' always indicates
 980                a decimal floating point number regardless of the radix.  */
 981             else if (!got_dot && *p == '.')
 982               got_dot = 1;
 983             else if (got_e && (p[-1] == 'e' || p[-1] == 'E')
 984                      && (*p == '-' || *p == '+'))
 985               /* This is the sign of the exponent, not the end of the
 986                  number.  */
 987               continue;
 988             /* We will take any letters or digits.  parse_number will
 989                complain if past the radix, or if L or U are not final.  */
 990             else if ((*p < '0' || *p > '9')
 991                      && ((*p < 'a' || *p > 'z')
 992                                   && (*p < 'A' || *p > 'Z')))
 993               break;
 994           }
 995         toktype = parse_number (tokstart, p - tokstart, got_dot|got_e, &yylval);
 996         if (toktype == ERROR)
 997           {
 998             char *err_copy = (char *) alloca (p - tokstart + 1);
 999
1000             memcpy (err_copy, tokstart, p - tokstart);
1001             err_copy[p - tokstart] = 0;
1002             error ("Invalid number \"%s\".", err_copy);
1003           }
1004         lexptr = p;
1005         return toktype;
1006       }
1007
1008     case '+':
1009     case '-':
1010     case '*':
1011     case '/':
1012     case '%':
1013     case '|':
1014     case '&':
1015     case '^':
1016     case '~':
1017     case '!':
1018     case '<':
1019     case '>':
1020     case '[':
1021     case ']':
1022     case '?':
1023     case ':':
1024     case '=':
1025     case '{':
1026     case '}':
1027     symbol:
1028       lexptr++;
1029       return c;
1030
1031     case '"':
1032
1033       /* Build the gdb internal form of the input string in tempbuf,
1034          translating any standard C escape forms seen.  Note that the
1035          buffer is null byte terminated *only* for the convenience of
1036          debugging gdb itself and printing the buffer contents when
1037          the buffer contains no embedded nulls.  Gdb does not depend
1038          upon the buffer being null byte terminated, it uses the length
1039          string instead.  This allows gdb to handle C strings (as well
1040          as strings in other languages) with embedded null bytes */
1041
1042       tokptr = ++tokstart;
1043       tempbufindex = 0;
1044
1045       do {
1046         /* Grow the static temp buffer if necessary, including allocating
1047            the first one on demand. */
1048         if (tempbufindex + 1 >= tempbufsize)
1049           {
1050             tempbuf = (char *) realloc (tempbuf, tempbufsize += 64);
1051           }
1052         switch (*tokptr)
1053           {
1054           case '\0':
1055           case '"':
1056             /* Do nothing, loop will terminate. */
1057             break;
1058           case '\\':
1059             tokptr++;
1060             c = parse_escape (&tokptr);
1061             if (c == -1)
1062               {
1063                 continue;
1064               }
1065             tempbuf[tempbufindex++] = c;
1066             break;
1067           default:
1068             tempbuf[tempbufindex++] = *tokptr++;
1069             break;
1070           }
1071       } while ((*tokptr != '"') && (*tokptr != '\0'));
1072       if (*tokptr++ != '"')
1073         {
1074           error ("Unterminated string in expression.");
1075         }
1076       tempbuf[tempbufindex] = '\0';     /* See note above */
1077       yylval.sval.ptr = tempbuf;
1078       yylval.sval.length = tempbufindex;
1079       lexptr = tokptr;
1080       return (STRING_LITERAL);
1081     }
1082
1083   if (!(c == '_' || c == '$'
1084         || (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z')))
1085     /* We must have come across a bad character (e.g. ';').  */
1086     error ("Invalid character '%c' in expression.", c);
1087
1088   /* It's a name.  See how long it is.  */
1089   namelen = 0;
1090   for (c = tokstart[namelen];
1091        (c == '_' || c == '$' || (c >= '0' && c <= '9')
1092         || (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || c == '<');)
1093     {
1094       if (c == '<')
1095         {
1096           int i = namelen;
1097           while (tokstart[++i] && tokstart[i] != '>');
1098           if (tokstart[i] == '>')
1099             namelen = i;
1100         }
1101        c = tokstart[++namelen];
1102      }
1103
1104   /* The token "if" terminates the expression and is NOT
1105      removed from the input stream.  */
1106   if (namelen == 2 && tokstart[0] == 'i' && tokstart[1] == 'f')
1107     {
1108       return 0;
1109     }
1110
1111   lexptr += namelen;
1112
1113   tryname:
1114
1115   /* Catch specific keywords.  Should be done with a data structure.  */
1116   switch (namelen)
1117     {
1118     case 7:
1119       if (STREQN (tokstart, "boolean", 7))
1120         return BOOLEAN;
1121       break;
1122     case 6:
1123       if (STREQN (tokstart, "double", 6))
1124         return DOUBLE;
1125       break;
1126     case 5:
1127       if (STREQN (tokstart, "short", 5))
1128         return SHORT;
1129       if (STREQN (tokstart, "false", 5))
1130         {
1131           yylval.lval = 0;
1132           return BOOLEAN_LITERAL;
1133         }
1134       if (STREQN (tokstart, "super", 5))
1135         return SUPER;
1136       if (STREQN (tokstart, "float", 5))
1137         return FLOAT;
1138       break;
1139     case 4:
1140       if (STREQN (tokstart, "long", 4))
1141         return LONG;
1142       if (STREQN (tokstart, "byte", 4))
1143         return BYTE;
1144       if (STREQN (tokstart, "char", 4))
1145         return CHAR;
1146       if (STREQN (tokstart, "true", 4))
1147         {
1148           yylval.lval = 1;
1149           return BOOLEAN_LITERAL;
1150         }
1151       if (current_language->la_language == language_cplus
1152           && STREQN (tokstart, "this", 4))
1153         {
1154           static const char this_name[] =
1155                                  { CPLUS_MARKER, 't', 'h', 'i', 's', '\0' };
1156
1157           if (lookup_symbol (this_name, expression_context_block,
1158                              VAR_NAMESPACE, (int *) NULL,
1159                              (struct symtab **) NULL))
1160             return THIS;
1161         }
1162       break;
1163     case 3:
1164       if (STREQN (tokstart, "int", 3))
1165         return INT;
1166       if (STREQN (tokstart, "new", 3))
1167         return NEW;
1168       break;
1169     default:
1170       break;
1171     }
1172
1173   yylval.sval.ptr = tokstart;
1174   yylval.sval.length = namelen;
1175
1176   if (*tokstart == '$')
1177     {
1178       write_dollar_variable (yylval.sval);
1179       return VARIABLE;
1180     }
1181
1182   /* Input names that aren't symbols but ARE valid hex numbers,
1183      when the input radix permits them, can be names or numbers
1184      depending on the parse.  Note we support radixes > 16 here.  */
1185   if (((tokstart[0] >= 'a' && tokstart[0] < 'a' + input_radix - 10) ||
1186        (tokstart[0] >= 'A' && tokstart[0] < 'A' + input_radix - 10)))
1187     {
1188       YYSTYPE newlval;  /* Its value is ignored.  */
1189       int hextype = parse_number (tokstart, namelen, 0, &newlval);
1190       if (hextype == INTEGER_LITERAL)
1191         return NAME_OR_INT;
1192     }
1193   return IDENTIFIER;
1194 }
1195
1196 void
1197 yyerror (msg)
1198      char *msg;
1199 {
1200   error ("A %s in expression, near `%s'.", (msg ? msg : "error"), lexptr);
1201 }
1202
1203 static struct type *
1204 java_type_from_name (name)
1205      struct stoken name;
1206
1207 {
1208   char *tmp = copy_name (name);
1209   struct type *typ = java_lookup_class (tmp);
1210   if (typ == NULL || TYPE_CODE (typ) != TYPE_CODE_STRUCT)
1211     error ("No class named %s.", tmp);
1212   return typ;
1213 }
1214
1215 /* If NAME is a valid variable name in this scope, push it and return 1.
1216    Otherwise, return 0. */
1217
1218 static int
1219 push_variable (name)
1220      struct stoken name;
1221
1222 {
1223   char *tmp = copy_name (name);
1224   int is_a_field_of_this = 0;
1225   struct symbol *sym;
1226   sym = lookup_symbol (tmp, expression_context_block, VAR_NAMESPACE,
1227                        &is_a_field_of_this, (struct symtab **) NULL);
1228   if (sym && SYMBOL_CLASS (sym) != LOC_TYPEDEF)
1229     {
1230       if (symbol_read_needs_frame (sym))
1231         {
1232           if (innermost_block == 0 ||
1233               contained_in (block_found, innermost_block))
1234             innermost_block = block_found;
1235         }
1236
1237       write_exp_elt_opcode (OP_VAR_VALUE);
1238       /* We want to use the selected frame, not another more inner frame
1239          which happens to be in the same block.  */
1240       write_exp_elt_block (NULL);
1241       write_exp_elt_sym (sym);
1242       write_exp_elt_opcode (OP_VAR_VALUE);
1243       return 1;
1244     }
1245   if (is_a_field_of_this)
1246     {
1247       /* it hangs off of `this'.  Must not inadvertently convert from a
1248          method call to data ref.  */
1249       if (innermost_block == 0 ||
1250           contained_in (block_found, innermost_block))
1251         innermost_block = block_found;
1252       write_exp_elt_opcode (OP_THIS);
1253       write_exp_elt_opcode (OP_THIS);
1254       write_exp_elt_opcode (STRUCTOP_PTR);
1255       write_exp_string (name);
1256       write_exp_elt_opcode (STRUCTOP_PTR);
1257       return 1;
1258     }
1259   return 0;
1260 }
1261
1262 /* Assuming a reference expression has been pushed, emit the
1263    STRUCTOP_STRUCT ops to access the field named NAME.  If NAME is a
1264    qualified name (has '.'), generate a field access for each part. */
1265
1266 static void
1267 push_fieldnames (name)
1268      struct stoken name;
1269 {
1270   int i;
1271   struct stoken token;
1272   token.ptr = name.ptr;
1273   for (i = 0;  ;  i++)
1274     {
1275       if (i == name.length || name.ptr[i] == '.')
1276         {
1277           /* token.ptr is start of current field name. */
1278           token.length = &name.ptr[i] - token.ptr;
1279           write_exp_elt_opcode (STRUCTOP_STRUCT);
1280           write_exp_string (token);
1281           write_exp_elt_opcode (STRUCTOP_STRUCT);
1282           token.ptr += token.length + 1;
1283         }
1284       if (i >= name.length)
1285         break;
1286     }
1287 }
1288
1289 /* Helper routine for push_expression_name.
1290    Handle a qualified name, where DOT_INDEX is the index of the first '.' */
1291
1292 static void
1293 push_qualified_expression_name (name, dot_index)
1294      struct stoken name;
1295      int dot_index;
1296 {
1297   struct stoken token;
1298   char *tmp;
1299   struct type *typ;
1300
1301   token.ptr = name.ptr;
1302   token.length = dot_index;
1303
1304   if (push_variable (token))
1305     {
1306       token.ptr = name.ptr + dot_index + 1;
1307       token.length = name.length - dot_index - 1;
1308       push_fieldnames (token);
1309       return;
1310     }
1311
1312   token.ptr = name.ptr;
1313   for (;;)
1314     {
1315       token.length = dot_index;
1316       tmp = copy_name (token);
1317       typ = java_lookup_class (tmp);
1318       if (typ != NULL)
1319         {
1320           if (dot_index == name.length)
1321             {
1322               write_exp_elt_opcode(OP_TYPE);
1323               write_exp_elt_type(typ);
1324               write_exp_elt_opcode(OP_TYPE);
1325               return;
1326             }
1327           dot_index++;  /* Skip '.' */
1328           name.ptr += dot_index;
1329           name.length -= dot_index;
1330           dot_index = 0;
1331           while (dot_index < name.length && name.ptr[dot_index] != '.')
1332             dot_index++;
1333           token.ptr = name.ptr;
1334           token.length = dot_index;
1335           write_exp_elt_opcode (OP_SCOPE);
1336           write_exp_elt_type (typ);
1337           write_exp_string (token);
1338           write_exp_elt_opcode (OP_SCOPE);
1339           if (dot_index < name.length)
1340             {
1341               dot_index++;
1342               name.ptr += dot_index;
1343               name.length -= dot_index;
1344               push_fieldnames (name);
1345             }
1346           return;
1347         }
1348       else if (dot_index >= name.length)
1349         break;
1350       dot_index++;  /* Skip '.' */
1351       while (dot_index < name.length && name.ptr[dot_index] != '.')
1352         dot_index++;
1353     }
1354   error ("unknown type `%.*s'", name.length, name.ptr);
1355 }
1356
1357 /* Handle Name in an expression (or LHS).
1358    Handle VAR, TYPE, TYPE.FIELD1....FIELDN and VAR.FIELD1....FIELDN. */
1359
1360 static void
1361 push_expression_name (name)
1362      struct stoken name;
1363 {
1364   char *tmp;
1365   struct type *typ;
1366   char *ptr;
1367   int i;
1368
1369   for (i = 0;  i < name.length;  i++)
1370     {
1371       if (name.ptr[i] == '.')
1372         {
1373           /* It's a Qualified Expression Name. */
1374           push_qualified_expression_name (name, i);
1375           return;
1376         }
1377     }
1378
1379   /* It's a Simple Expression Name. */
1380
1381   if (push_variable (name))
1382     return;
1383   tmp = copy_name (name);
1384   typ = java_lookup_class (tmp);
1385   if (typ != NULL)
1386     {
1387       write_exp_elt_opcode(OP_TYPE);
1388       write_exp_elt_type(typ);
1389       write_exp_elt_opcode(OP_TYPE);
1390     }
1391   else
1392     {
1393       struct minimal_symbol *msymbol;
1394
1395       msymbol = lookup_minimal_symbol (tmp, NULL, NULL);
1396       if (msymbol != NULL)
1397         {
1398           write_exp_msymbol (msymbol,
1399                              lookup_function_type (builtin_type_int),
1400                              builtin_type_int);
1401         }
1402       else if (!have_full_symbols () && !have_partial_symbols ())
1403         error ("No symbol table is loaded.  Use the \"file\" command.");
1404       else
1405         error ("No symbol \"%s\" in current context.", tmp);
1406     }
1407
1408 }
1409
1410
1411 /* The following two routines, copy_exp and insert_exp, aren't specific to
1412    Java, so they could go in parse.c, but their only purpose is to support
1413    the parsing kludges we use in this file, so maybe it's best to isolate
1414    them here.  */
1415
1416 /* Copy the expression whose last element is at index ENDPOS - 1 in EXPR
1417    into a freshly malloc'ed struct expression.  Its language_defn is set
1418    to null.  */
1419 static struct expression *
1420 copy_exp (expr, endpos)
1421      struct expression *expr;
1422      int endpos;
1423 {
1424   int len = length_of_subexp (expr, endpos);
1425   struct expression *new
1426     = (struct expression *) malloc (sizeof (*new) + EXP_ELEM_TO_BYTES (len));
1427   new->nelts = len;
1428   memcpy (new->elts, expr->elts + endpos - len, EXP_ELEM_TO_BYTES (len));
1429   new->language_defn = 0;
1430
1431   return new;
1432 }
1433
1434 /* Insert the expression NEW into the current expression (expout) at POS.  */
1435 static void
1436 insert_exp (pos, new)
1437      int pos;
1438      struct expression *new;
1439 {
1440   int newlen = new->nelts;
1441
1442   /* Grow expout if necessary.  In this function's only use at present,
1443      this should never be necessary.  */
1444   if (expout_ptr + newlen > expout_size)
1445     {
1446       expout_size = max (expout_size * 2, expout_ptr + newlen + 10);
1447       expout = (struct expression *)
1448         realloc ((char *) expout, (sizeof (struct expression)
1449                                     + EXP_ELEM_TO_BYTES (expout_size)));
1450     }
1451
1452   {
1453     int i;
1454
1455     for (i = expout_ptr - 1; i >= pos; i--)
1456       expout->elts[i + newlen] = expout->elts[i];
1457   }
1458
1459   memcpy (expout->elts + pos, new->elts, EXP_ELEM_TO_BYTES (newlen));
1460   expout_ptr += newlen;
1461 }