gdb/jv-exp.y

   1 /* YACC parser for Java expressions, for GDB.
   2    Copyright (C) 1997, 1998, 1999, 2000, 2006
   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., 51 Franklin Street, Fifth Floor,
  20 Boston, MA 02110-1301, USA.  */
  21
  22 /* Parse a Java expression from text in a string,
  23    and return the result as a  struct expression  pointer.
  24    That structure contains arithmetic operations in reverse polish,
  25    with constants represented by operations that are followed by special data.
  26    See expression.h for the details of the format.
  27    What is important here is that it can be built up sequentially
  28    during the process of parsing; the lower levels of the tree always
  29    come first in the result.  Well, almost always; see ArrayAccess.
  30
  31    Note that malloc's and realloc's in this file are transformed to
  32    xmalloc and xrealloc respectively by the same sed command in the
  33    makefile that remaps any other malloc/realloc inserted by the parser
  34    generator.  Doing this with #defines and trying to control the interaction
  35    with include files (<malloc.h> and <stdlib.h> for example) just became
  36    too messy, particularly when such includes can be inserted at random
  37    times by the parser generator.  */
  38
  39 %{
  40
  41 #include "defs.h"
  42 #include "gdb_string.h"
  43 #include <ctype.h>
  44 #include "expression.h"
  45 #include "value.h"
  46 #include "parser-defs.h"
  47 #include "language.h"
  48 #include "jv-lang.h"
  49 #include "bfd.h" /* Required by objfiles.h.  */
  50 #include "symfile.h" /* Required by objfiles.h.  */
  51 #include "objfiles.h" /* For have_full_symbols and have_partial_symbols */
  52 #include "block.h"
  53
  54 /* Remap normal yacc parser interface names (yyparse, yylex, yyerror, etc),
  55    as well as gratuitiously global symbol names, so we can have multiple
  56    yacc generated parsers in gdb.  Note that these are only the variables
  57    produced by yacc.  If other parser generators (bison, byacc, etc) produce
  58    additional global names that conflict at link time, then those parser
  59    generators need to be fixed instead of adding those names to this list. */
  60
  61 #define yymaxdepth java_maxdepth
  62 #define yyparse java_parse
  63 #define yylex   java_lex
  64 #define yyerror java_error
  65 #define yylval  java_lval
  66 #define yychar  java_char
  67 #define yydebug java_debug
  68 #define yypact  java_pact
  69 #define yyr1    java_r1
  70 #define yyr2    java_r2
  71 #define yydef   java_def
  72 #define yychk   java_chk
  73 #define yypgo   java_pgo
  74 #define yyact   java_act
  75 #define yyexca  java_exca
  76 #define yyerrflag java_errflag
  77 #define yynerrs java_nerrs
  78 #define yyps    java_ps
  79 #define yypv    java_pv
  80 #define yys     java_s
  81 #define yy_yys  java_yys
  82 #define yystate java_state
  83 #define yytmp   java_tmp
  84 #define yyv     java_v
  85 #define yy_yyv  java_yyv
  86 #define yyval   java_val
  87 #define yylloc  java_lloc
  88 #define yyreds  java_reds               /* With YYDEBUG defined */
  89 #define yytoks  java_toks               /* With YYDEBUG defined */
  90 #define yyname  java_name               /* With YYDEBUG defined */
  91 #define yyrule  java_rule               /* With YYDEBUG defined */
  92 #define yylhs   java_yylhs
  93 #define yylen   java_yylen
  94 #define yydefred java_yydefred
  95 #define yydgoto java_yydgoto
  96 #define yysindex java_yysindex
  97 #define yyrindex java_yyrindex
  98 #define yygindex java_yygindex
  99 #define yytable  java_yytable
 100 #define yycheck  java_yycheck
 101
 102 #ifndef YYDEBUG
 103 #define YYDEBUG 1               /* Default to yydebug support */
 104 #endif
 105
 106 #define YYFPRINTF parser_fprintf
 107
 108 int yyparse (void);
 109
 110 static int yylex (void);
 111
 112 void yyerror (char *);
 113
 114 static struct type *java_type_from_name (struct stoken);
 115 static void push_expression_name (struct stoken);
 116 static void push_fieldnames (struct stoken);
 117
 118 static struct expression *copy_exp (struct expression *, int);
 119 static void insert_exp (int, struct expression *);
 120
 121 %}
 122
 123 /* Although the yacc "value" of an expression is not used,
 124    since the result is stored in the structure being created,
 125    other node types do have values.  */
 126
 127 %union
 128   {
 129     LONGEST lval;
 130     struct {
 131       LONGEST val;
 132       struct type *type;
 133     } typed_val_int;
 134     struct {
 135       DOUBLEST dval;
 136       struct type *type;
 137     } typed_val_float;
 138     struct symbol *sym;
 139     struct type *tval;
 140     struct stoken sval;
 141     struct ttype tsym;
 142     struct symtoken ssym;
 143     struct block *bval;
 144     enum exp_opcode opcode;
 145     struct internalvar *ivar;
 146     int *ivec;
 147   }
 148
 149 %{
 150 /* YYSTYPE gets defined by %union */
 151 static int parse_number (char *, int, int, YYSTYPE *);
 152 %}
 153
 154 %type <lval> rcurly Dims Dims_opt
 155 %type <tval> ClassOrInterfaceType ClassType /* ReferenceType Type ArrayType */
 156 %type <tval> IntegralType FloatingPointType NumericType PrimitiveType ArrayType PrimitiveOrArrayType
 157
 158 %token <typed_val_int> INTEGER_LITERAL
 159 %token <typed_val_float> FLOATING_POINT_LITERAL
 160
 161 %token <sval> IDENTIFIER
 162 %token <sval> STRING_LITERAL
 163 %token <lval> BOOLEAN_LITERAL
 164 %token <tsym> TYPENAME
 165 %type <sval> Name SimpleName QualifiedName ForcedName
 166
 167 /* A NAME_OR_INT is a symbol which is not known in the symbol table,
 168    but which would parse as a valid number in the current input radix.
 169    E.g. "c" when input_radix==16.  Depending on the parse, it will be
 170    turned into a name or into a number.  */
 171
 172 %token <sval> NAME_OR_INT
 173
 174 %token ERROR
 175
 176 /* Special type cases, put in to allow the parser to distinguish different
 177    legal basetypes.  */
 178 %token LONG SHORT BYTE INT CHAR BOOLEAN DOUBLE FLOAT
 179
 180 %token VARIABLE
 181
 182 %token <opcode> ASSIGN_MODIFY
 183
 184 %token SUPER NEW
 185
 186 %left ','
 187 %right '=' ASSIGN_MODIFY
 188 %right '?'
 189 %left OROR
 190 %left ANDAND
 191 %left '|'
 192 %left '^'
 193 %left '&'
 194 %left EQUAL NOTEQUAL
 195 %left '<' '>' LEQ GEQ
 196 %left LSH RSH
 197 %left '+' '-'
 198 %left '*' '/' '%'
 199 %right INCREMENT DECREMENT
 200 %right '.' '[' '('
 201
 202 \f
 203 %%
 204
 205 start   :       exp1
 206         |       type_exp
 207         ;
 208
 209 type_exp:       PrimitiveOrArrayType
 210                 {
 211                   write_exp_elt_opcode(OP_TYPE);
 212                   write_exp_elt_type($1);
 213                   write_exp_elt_opcode(OP_TYPE);
 214                 }
 215         ;
 216
 217 PrimitiveOrArrayType:
 218                 PrimitiveType
 219         |       ArrayType
 220         ;
 221
 222 StringLiteral:
 223         STRING_LITERAL
 224                 {
 225                   write_exp_elt_opcode (OP_STRING);
 226                   write_exp_string ($1);
 227                   write_exp_elt_opcode (OP_STRING);
 228                 }
 229 ;
 230
 231 Literal:
 232         INTEGER_LITERAL
 233                 { write_exp_elt_opcode (OP_LONG);
 234                   write_exp_elt_type ($1.type);
 235                   write_exp_elt_longcst ((LONGEST)($1.val));
 236                   write_exp_elt_opcode (OP_LONG); }
 237 |       NAME_OR_INT
 238                 { YYSTYPE val;
 239                   parse_number ($1.ptr, $1.length, 0, &val);
 240                   write_exp_elt_opcode (OP_LONG);
 241                   write_exp_elt_type (val.typed_val_int.type);
 242                   write_exp_elt_longcst ((LONGEST)val.typed_val_int.val);
 243                   write_exp_elt_opcode (OP_LONG);
 244                 }
 245 |       FLOATING_POINT_LITERAL
 246                 { write_exp_elt_opcode (OP_DOUBLE);
 247                   write_exp_elt_type ($1.type);
 248                   write_exp_elt_dblcst ($1.dval);
 249                   write_exp_elt_opcode (OP_DOUBLE); }
 250 |       BOOLEAN_LITERAL
 251                 { write_exp_elt_opcode (OP_LONG);
 252                   write_exp_elt_type (java_boolean_type);
 253                   write_exp_elt_longcst ((LONGEST)$1);
 254                   write_exp_elt_opcode (OP_LONG); }
 255 |       StringLiteral
 256         ;
 257
 258 /* UNUSED:
 259 Type:
 260         PrimitiveType
 261 |       ReferenceType
 262 ;
 263 */
 264
 265 PrimitiveType:
 266         NumericType
 267 |       BOOLEAN
 268                 { $$ = java_boolean_type; }
 269 ;
 270
 271 NumericType:
 272         IntegralType
 273 |       FloatingPointType
 274 ;
 275
 276 IntegralType:
 277         BYTE
 278                 { $$ = java_byte_type; }
 279 |       SHORT
 280                 { $$ = java_short_type; }
 281 |       INT
 282                 { $$ = java_int_type; }
 283 |       LONG
 284                 { $$ = java_long_type; }
 285 |       CHAR
 286                 { $$ = java_char_type; }
 287 ;
 288
 289 FloatingPointType:
 290         FLOAT
 291                 { $$ = java_float_type; }
 292 |       DOUBLE
 293                 { $$ = java_double_type; }
 294 ;
 295
 296 /* UNUSED:
 297 ReferenceType:
 298         ClassOrInterfaceType
 299 |       ArrayType
 300 ;
 301 */
 302
 303 ClassOrInterfaceType:
 304         Name
 305                 { $$ = java_type_from_name ($1); }
 306 ;
 307
 308 ClassType:
 309         ClassOrInterfaceType
 310 ;
 311
 312 ArrayType:
 313         PrimitiveType Dims
 314                 { $$ = java_array_type ($1, $2); }
 315 |       Name Dims
 316                 { $$ = java_array_type (java_type_from_name ($1), $2); }
 317 ;
 318
 319 Name:
 320         IDENTIFIER
 321 |       QualifiedName
 322 ;
 323
 324 ForcedName:
 325         SimpleName
 326 |       QualifiedName
 327 ;
 328
 329 SimpleName:
 330         IDENTIFIER
 331 |       NAME_OR_INT
 332 ;
 333
 334 QualifiedName:
 335         Name '.' SimpleName
 336                 { $$.length = $1.length + $3.length + 1;
 337                   if ($1.ptr + $1.length + 1 == $3.ptr
 338                       && $1.ptr[$1.length] == '.')
 339                     $$.ptr = $1.ptr;  /* Optimization. */
 340                   else
 341                     {
 342                       $$.ptr = (char *) malloc ($$.length + 1);
 343                       make_cleanup (free, $$.ptr);
 344                       sprintf ($$.ptr, "%.*s.%.*s",
 345                                $1.length, $1.ptr, $3.length, $3.ptr);
 346                 } }
 347 ;
 348
 349 /*
 350 type_exp:       type
 351                         { write_exp_elt_opcode(OP_TYPE);
 352                           write_exp_elt_type($1);
 353                           write_exp_elt_opcode(OP_TYPE);}
 354         ;
 355         */
 356
 357 /* Expressions, including the comma operator.  */
 358 exp1    :       Expression
 359         |       exp1 ',' Expression
 360                         { write_exp_elt_opcode (BINOP_COMMA); }
 361         ;
 362
 363 Primary:
 364         PrimaryNoNewArray
 365 |       ArrayCreationExpression
 366 ;
 367
 368 PrimaryNoNewArray:
 369         Literal
 370 |       '(' Expression ')'
 371 |       ClassInstanceCreationExpression
 372 |       FieldAccess
 373 |       MethodInvocation
 374 |       ArrayAccess
 375 |       lcurly ArgumentList rcurly
 376                 { write_exp_elt_opcode (OP_ARRAY);
 377                   write_exp_elt_longcst ((LONGEST) 0);
 378                   write_exp_elt_longcst ((LONGEST) $3);
 379                   write_exp_elt_opcode (OP_ARRAY); }
 380 ;
 381
 382 lcurly:
 383         '{'
 384                 { start_arglist (); }
 385 ;
 386
 387 rcurly:
 388         '}'
 389                 { $$ = end_arglist () - 1; }
 390 ;
 391
 392 ClassInstanceCreationExpression:
 393         NEW ClassType '(' ArgumentList_opt ')'
 394                 { internal_error (__FILE__, __LINE__,
 395                                   _("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                 { internal_error (__FILE__, __LINE__,
 414                                   _("FIXME - ArrayCreationExpression")); }
 415 |       NEW ClassOrInterfaceType DimExprs Dims_opt
 416                 { internal_error (__FILE__, __LINE__,
 417                                   _("FIXME - ArrayCreationExpression")); }
 418 ;
 419
 420 DimExprs:
 421         DimExpr
 422 |       DimExprs DimExpr
 423 ;
 424
 425 DimExpr:
 426         '[' Expression ']'
 427 ;
 428
 429 Dims:
 430         '[' ']'
 431                 { $$ = 1; }
 432 |       Dims '[' ']'
 433         { $$ = $1 + 1; }
 434 ;
 435
 436 Dims_opt:
 437         Dims
 438 |       /* EMPTY */
 439                 { $$ = 0; }
 440 ;
 441
 442 FieldAccess:
 443         Primary '.' SimpleName
 444                 { push_fieldnames ($3); }
 445 |       VARIABLE '.' SimpleName
 446                 { push_fieldnames ($3); }
 447 /*|     SUPER '.' SimpleName { FIXME } */
 448 ;
 449
 450 FuncStart:
 451         Name '('
 452                 { push_expression_name ($1); }
 453 ;
 454
 455 MethodInvocation:
 456         FuncStart
 457                 { start_arglist(); }
 458         ArgumentList_opt ')'
 459                 { write_exp_elt_opcode (OP_FUNCALL);
 460                   write_exp_elt_longcst ((LONGEST) end_arglist ());
 461                   write_exp_elt_opcode (OP_FUNCALL); }
 462 |       Primary '.' SimpleName '(' ArgumentList_opt ')'
 463                 { error (_("Form of method invocation not implemented")); }
 464 |       SUPER '.' SimpleName '(' ArgumentList_opt ')'
 465                 { error (_("Form of method invocation not implemented")); }
 466 ;
 467
 468 ArrayAccess:
 469         Name '[' Expression ']'
 470                 {
 471                   /* Emit code for the Name now, then exchange it in the
 472                      expout array with the Expression's code.  We could
 473                      introduce a OP_SWAP code or a reversed version of
 474                      BINOP_SUBSCRIPT, but that makes the rest of GDB pay
 475                      for our parsing kludges.  */
 476                   struct expression *name_expr;
 477
 478                   push_expression_name ($1);
 479                   name_expr = copy_exp (expout, expout_ptr);
 480                   expout_ptr -= name_expr->nelts;
 481                   insert_exp (expout_ptr-length_of_subexp (expout, expout_ptr),
 482                               name_expr);
 483                   free (name_expr);
 484                   write_exp_elt_opcode (BINOP_SUBSCRIPT);
 485                 }
 486 |       VARIABLE '[' Expression ']'
 487                 { write_exp_elt_opcode (BINOP_SUBSCRIPT); }
 488 |       PrimaryNoNewArray '[' Expression ']'
 489                 { write_exp_elt_opcode (BINOP_SUBSCRIPT); }
 490 ;
 491
 492 PostfixExpression:
 493         Primary
 494 |       Name
 495                 { push_expression_name ($1); }
 496 |       VARIABLE
 497                 /* Already written by write_dollar_variable. */
 498 |       PostIncrementExpression
 499 |       PostDecrementExpression
 500 ;
 501
 502 PostIncrementExpression:
 503         PostfixExpression INCREMENT
 504                 { write_exp_elt_opcode (UNOP_POSTINCREMENT); }
 505 ;
 506
 507 PostDecrementExpression:
 508         PostfixExpression DECREMENT
 509                 { write_exp_elt_opcode (UNOP_POSTDECREMENT); }
 510 ;
 511
 512 UnaryExpression:
 513         PreIncrementExpression
 514 |       PreDecrementExpression
 515 |       '+' UnaryExpression
 516 |       '-' UnaryExpression
 517                 { write_exp_elt_opcode (UNOP_NEG); }
 518 |       '*' UnaryExpression
 519                 { write_exp_elt_opcode (UNOP_IND); } /*FIXME not in Java  */
 520 |       UnaryExpressionNotPlusMinus
 521 ;
 522
 523 PreIncrementExpression:
 524         INCREMENT UnaryExpression
 525                 { write_exp_elt_opcode (UNOP_PREINCREMENT); }
 526 ;
 527
 528 PreDecrementExpression:
 529         DECREMENT UnaryExpression
 530                 { write_exp_elt_opcode (UNOP_PREDECREMENT); }
 531 ;
 532
 533 UnaryExpressionNotPlusMinus:
 534         PostfixExpression
 535 |       '~' UnaryExpression
 536                 { write_exp_elt_opcode (UNOP_COMPLEMENT); }
 537 |       '!' UnaryExpression
 538                 { write_exp_elt_opcode (UNOP_LOGICAL_NOT); }
 539 |       CastExpression
 540         ;
 541
 542 CastExpression:
 543         '(' PrimitiveType Dims_opt ')' UnaryExpression
 544                 { write_exp_elt_opcode (UNOP_CAST);
 545                   write_exp_elt_type (java_array_type ($2, $3));
 546                   write_exp_elt_opcode (UNOP_CAST); }
 547 |       '(' Expression ')' UnaryExpressionNotPlusMinus
 548                 {
 549                   int exp_size = expout_ptr;
 550                   int last_exp_size = length_of_subexp(expout, expout_ptr);
 551                   struct type *type;
 552                   int i;
 553                   int base = expout_ptr - last_exp_size - 3;
 554                   if (base < 0 || expout->elts[base+2].opcode != OP_TYPE)
 555                     error (_("Invalid cast expression"));
 556                   type = expout->elts[base+1].type;
 557                   /* Remove the 'Expression' and slide the
 558                      UnaryExpressionNotPlusMinus down to replace it. */
 559                   for (i = 0;  i < last_exp_size;  i++)
 560                     expout->elts[base + i] = expout->elts[base + i + 3];
 561                   expout_ptr -= 3;
 562                   if (TYPE_CODE (type) == TYPE_CODE_STRUCT)
 563                     type = lookup_pointer_type (type);
 564                   write_exp_elt_opcode (UNOP_CAST);
 565                   write_exp_elt_type (type);
 566                   write_exp_elt_opcode (UNOP_CAST);
 567                 }
 568 |       '(' Name Dims ')' UnaryExpressionNotPlusMinus
 569                 { write_exp_elt_opcode (UNOP_CAST);
 570                   write_exp_elt_type (java_array_type (java_type_from_name ($2), $3));
 571                   write_exp_elt_opcode (UNOP_CAST); }
 572 ;
 573
 574
 575 MultiplicativeExpression:
 576         UnaryExpression
 577 |       MultiplicativeExpression '*' UnaryExpression
 578                 { write_exp_elt_opcode (BINOP_MUL); }
 579 |       MultiplicativeExpression '/' UnaryExpression
 580                 { write_exp_elt_opcode (BINOP_DIV); }
 581 |       MultiplicativeExpression '%' UnaryExpression
 582                 { write_exp_elt_opcode (BINOP_REM); }
 583 ;
 584
 585 AdditiveExpression:
 586         MultiplicativeExpression
 587 |       AdditiveExpression '+' MultiplicativeExpression
 588                 { write_exp_elt_opcode (BINOP_ADD); }
 589 |       AdditiveExpression '-' MultiplicativeExpression
 590                 { write_exp_elt_opcode (BINOP_SUB); }
 591 ;
 592
 593 ShiftExpression:
 594         AdditiveExpression
 595 |       ShiftExpression LSH AdditiveExpression
 596                 { write_exp_elt_opcode (BINOP_LSH); }
 597 |       ShiftExpression RSH AdditiveExpression
 598                 { write_exp_elt_opcode (BINOP_RSH); }
 599 /* |    ShiftExpression >>> AdditiveExpression { FIXME } */
 600 ;
 601
 602 RelationalExpression:
 603         ShiftExpression
 604 |       RelationalExpression '<' ShiftExpression
 605                 { write_exp_elt_opcode (BINOP_LESS); }
 606 |       RelationalExpression '>' ShiftExpression
 607                 { write_exp_elt_opcode (BINOP_GTR); }
 608 |       RelationalExpression LEQ ShiftExpression
 609                 { write_exp_elt_opcode (BINOP_LEQ); }
 610 |       RelationalExpression GEQ ShiftExpression
 611                 { write_exp_elt_opcode (BINOP_GEQ); }
 612 /* | RelationalExpresion INSTANCEOF ReferenceType { FIXME } */
 613 ;
 614
 615 EqualityExpression:
 616         RelationalExpression
 617 |       EqualityExpression EQUAL RelationalExpression
 618                 { write_exp_elt_opcode (BINOP_EQUAL); }
 619 |       EqualityExpression NOTEQUAL RelationalExpression
 620                 { write_exp_elt_opcode (BINOP_NOTEQUAL); }
 621 ;
 622
 623 AndExpression:
 624         EqualityExpression
 625 |       AndExpression '&' EqualityExpression
 626                 { write_exp_elt_opcode (BINOP_BITWISE_AND); }
 627 ;
 628
 629 ExclusiveOrExpression:
 630         AndExpression
 631 |       ExclusiveOrExpression '^' AndExpression
 632                 { write_exp_elt_opcode (BINOP_BITWISE_XOR); }
 633 ;
 634 InclusiveOrExpression:
 635         ExclusiveOrExpression
 636 |       InclusiveOrExpression '|' ExclusiveOrExpression
 637                 { write_exp_elt_opcode (BINOP_BITWISE_IOR); }
 638 ;
 639
 640 ConditionalAndExpression:
 641         InclusiveOrExpression
 642 |       ConditionalAndExpression ANDAND InclusiveOrExpression
 643                 { write_exp_elt_opcode (BINOP_LOGICAL_AND); }
 644 ;
 645
 646 ConditionalOrExpression:
 647         ConditionalAndExpression
 648 |       ConditionalOrExpression OROR ConditionalAndExpression
 649                 { write_exp_elt_opcode (BINOP_LOGICAL_OR); }
 650 ;
 651
 652 ConditionalExpression:
 653         ConditionalOrExpression
 654 |       ConditionalOrExpression '?' Expression ':' ConditionalExpression
 655                 { write_exp_elt_opcode (TERNOP_COND); }
 656 ;
 657
 658 AssignmentExpression:
 659         ConditionalExpression
 660 |       Assignment
 661 ;
 662
 663 Assignment:
 664         LeftHandSide '=' ConditionalExpression
 665                 { write_exp_elt_opcode (BINOP_ASSIGN); }
 666 |       LeftHandSide ASSIGN_MODIFY ConditionalExpression
 667                 { write_exp_elt_opcode (BINOP_ASSIGN_MODIFY);
 668                   write_exp_elt_opcode ($2);
 669                   write_exp_elt_opcode (BINOP_ASSIGN_MODIFY); }
 670 ;
 671
 672 LeftHandSide:
 673         ForcedName
 674                 { push_expression_name ($1); }
 675 |       VARIABLE
 676                 /* Already written by write_dollar_variable. */
 677 |       FieldAccess
 678 |       ArrayAccess
 679 ;
 680
 681
 682 Expression:
 683         AssignmentExpression
 684 ;
 685
 686 %%
 687 /* Take care of parsing a number (anything that starts with a digit).
 688    Set yylval and return the token type; update lexptr.
 689    LEN is the number of characters in it.  */
 690
 691 /*** Needs some error checking for the float case ***/
 692
 693 static int
 694 parse_number (p, len, parsed_float, putithere)
 695      char *p;
 696      int len;
 697      int parsed_float;
 698      YYSTYPE *putithere;
 699 {
 700   ULONGEST n = 0;
 701   ULONGEST limit, limit_div_base;
 702
 703   int c;
 704   int base = input_radix;
 705
 706   struct type *type;
 707
 708   if (parsed_float)
 709     {
 710       /* It's a float since it contains a point or an exponent.  */
 711       char c;
 712       int num = 0;      /* number of tokens scanned by scanf */
 713       char saved_char = p[len];
 714
 715       p[len] = 0;       /* null-terminate the token */
 716       num = sscanf (p, DOUBLEST_SCAN_FORMAT "%c",
 717                     &putithere->typed_val_float.dval, &c);
 718       p[len] = saved_char;      /* restore the input stream */
 719       if (num != 1)             /* check scanf found ONLY a float ... */
 720         return ERROR;
 721       /* See if it has `f' or `d' suffix (float or double).  */
 722
 723       c = tolower (p[len - 1]);
 724
 725       if (c == 'f' || c == 'F')
 726         putithere->typed_val_float.type = builtin_type_float;
 727       else if (isdigit (c) || c == '.' || c == 'd' || c == 'D')
 728         putithere->typed_val_float.type = builtin_type_double;
 729       else
 730         return ERROR;
 731
 732       return FLOATING_POINT_LITERAL;
 733     }
 734
 735   /* Handle base-switching prefixes 0x, 0t, 0d, 0 */
 736   if (p[0] == '0')
 737     switch (p[1])
 738       {
 739       case 'x':
 740       case 'X':
 741         if (len >= 3)
 742           {
 743             p += 2;
 744             base = 16;
 745             len -= 2;
 746           }
 747         break;
 748
 749       case 't':
 750       case 'T':
 751       case 'd':
 752       case 'D':
 753         if (len >= 3)
 754           {
 755             p += 2;
 756             base = 10;
 757             len -= 2;
 758           }
 759         break;
 760
 761       default:
 762         base = 8;
 763         break;
 764       }
 765
 766   c = p[len-1];
 767   /* A paranoid calculation of (1<<64)-1. */
 768   limit = (ULONGEST)0xffffffff;
 769   limit = ((limit << 16) << 16) | limit;
 770   if (c == 'l' || c == 'L')
 771     {
 772       type = java_long_type;
 773       len--;
 774     }
 775   else
 776     {
 777       type = java_int_type;
 778     }
 779   limit_div_base = limit / (ULONGEST) base;
 780
 781   while (--len >= 0)
 782     {
 783       c = *p++;
 784       if (c >= '0' && c <= '9')
 785         c -= '0';
 786       else if (c >= 'A' && c <= 'Z')
 787         c -= 'A' - 10;
 788       else if (c >= 'a' && c <= 'z')
 789         c -= 'a' - 10;
 790       else
 791         return ERROR;   /* Char not a digit */
 792       if (c >= base)
 793         return ERROR;
 794       if (n > limit_div_base
 795           || (n *= base) > limit - c)
 796         error (_("Numeric constant too large"));
 797       n += c;
 798         }
 799
 800   /* If the type is bigger than a 32-bit signed integer can be, implicitly
 801      promote to long.  Java does not do this, so mark it as builtin_type_uint64
 802      rather than java_long_type.  0x80000000 will become -0x80000000 instead
 803      of 0x80000000L, because we don't know the sign at this point.
 804   */
 805   if (type == java_int_type && n > (ULONGEST)0x80000000)
 806     type = builtin_type_uint64;
 807
 808   putithere->typed_val_int.val = n;
 809   putithere->typed_val_int.type = type;
 810
 811   return INTEGER_LITERAL;
 812 }
 813
 814 struct token
 815 {
 816   char *operator;
 817   int token;
 818   enum exp_opcode opcode;
 819 };
 820
 821 static const struct token tokentab3[] =
 822   {
 823     {">>=", ASSIGN_MODIFY, BINOP_RSH},
 824     {"<<=", ASSIGN_MODIFY, BINOP_LSH}
 825   };
 826
 827 static const struct token tokentab2[] =
 828   {
 829     {"+=", ASSIGN_MODIFY, BINOP_ADD},
 830     {"-=", ASSIGN_MODIFY, BINOP_SUB},
 831     {"*=", ASSIGN_MODIFY, BINOP_MUL},
 832     {"/=", ASSIGN_MODIFY, BINOP_DIV},
 833     {"%=", ASSIGN_MODIFY, BINOP_REM},
 834     {"|=", ASSIGN_MODIFY, BINOP_BITWISE_IOR},
 835     {"&=", ASSIGN_MODIFY, BINOP_BITWISE_AND},
 836     {"^=", ASSIGN_MODIFY, BINOP_BITWISE_XOR},
 837     {"++", INCREMENT, BINOP_END},
 838     {"--", DECREMENT, BINOP_END},
 839     {"&&", ANDAND, BINOP_END},
 840     {"||", OROR, BINOP_END},
 841     {"<<", LSH, BINOP_END},
 842     {">>", RSH, BINOP_END},
 843     {"==", EQUAL, BINOP_END},
 844     {"!=", NOTEQUAL, BINOP_END},
 845     {"<=", LEQ, BINOP_END},
 846     {">=", GEQ, BINOP_END}
 847   };
 848
 849 /* Read one token, getting characters through lexptr.  */
 850
 851 static int
 852 yylex ()
 853 {
 854   int c;
 855   int namelen;
 856   unsigned int i;
 857   char *tokstart;
 858   char *tokptr;
 859   int tempbufindex;
 860   static char *tempbuf;
 861   static int tempbufsize;
 862
 863  retry:
 864
 865   prev_lexptr = lexptr;
 866
 867   tokstart = lexptr;
 868   /* See if it is a special token of length 3.  */
 869   for (i = 0; i < sizeof tokentab3 / sizeof tokentab3[0]; i++)
 870     if (strncmp (tokstart, tokentab3[i].operator, 3) == 0)
 871       {
 872         lexptr += 3;
 873         yylval.opcode = tokentab3[i].opcode;
 874         return tokentab3[i].token;
 875       }
 876
 877   /* See if it is a special token of length 2.  */
 878   for (i = 0; i < sizeof tokentab2 / sizeof tokentab2[0]; i++)
 879     if (strncmp (tokstart, tokentab2[i].operator, 2) == 0)
 880       {
 881         lexptr += 2;
 882         yylval.opcode = tokentab2[i].opcode;
 883         return tokentab2[i].token;
 884       }
 885
 886   switch (c = *tokstart)
 887     {
 888     case 0:
 889       return 0;
 890
 891     case ' ':
 892     case '\t':
 893     case '\n':
 894       lexptr++;
 895       goto retry;
 896
 897     case '\'':
 898       /* We either have a character constant ('0' or '\177' for example)
 899          or we have a quoted symbol reference ('foo(int,int)' in C++
 900          for example). */
 901       lexptr++;
 902       c = *lexptr++;
 903       if (c == '\\')
 904         c = parse_escape (&lexptr);
 905       else if (c == '\'')
 906         error (_("Empty character constant"));
 907
 908       yylval.typed_val_int.val = c;
 909       yylval.typed_val_int.type = java_char_type;
 910
 911       c = *lexptr++;
 912       if (c != '\'')
 913         {
 914           namelen = skip_quoted (tokstart) - tokstart;
 915           if (namelen > 2)
 916             {
 917               lexptr = tokstart + namelen;
 918               if (lexptr[-1] != '\'')
 919                 error (_("Unmatched single quote"));
 920               namelen -= 2;
 921               tokstart++;
 922               goto tryname;
 923             }
 924           error (_("Invalid character constant"));
 925         }
 926       return INTEGER_LITERAL;
 927
 928     case '(':
 929       paren_depth++;
 930       lexptr++;
 931       return c;
 932
 933     case ')':
 934       if (paren_depth == 0)
 935         return 0;
 936       paren_depth--;
 937       lexptr++;
 938       return c;
 939
 940     case ',':
 941       if (comma_terminates && paren_depth == 0)
 942         return 0;
 943       lexptr++;
 944       return c;
 945
 946     case '.':
 947       /* Might be a floating point number.  */
 948       if (lexptr[1] < '0' || lexptr[1] > '9')
 949         goto symbol;            /* Nope, must be a symbol. */
 950       /* FALL THRU into number case.  */
 951
 952     case '0':
 953     case '1':
 954     case '2':
 955     case '3':
 956     case '4':
 957     case '5':
 958     case '6':
 959     case '7':
 960     case '8':
 961     case '9':
 962       {
 963         /* It's a number.  */
 964         int got_dot = 0, got_e = 0, toktype;
 965         char *p = tokstart;
 966         int hex = input_radix > 10;
 967
 968         if (c == '0' && (p[1] == 'x' || p[1] == 'X'))
 969           {
 970             p += 2;
 971             hex = 1;
 972           }
 973         else if (c == '0' && (p[1]=='t' || p[1]=='T' || p[1]=='d' || p[1]=='D'))
 974           {
 975             p += 2;
 976             hex = 0;
 977           }
 978
 979         for (;; ++p)
 980           {
 981             /* This test includes !hex because 'e' is a valid hex digit
 982                and thus does not indicate a floating point number when
 983                the radix is hex.  */
 984             if (!hex && !got_e && (*p == 'e' || *p == 'E'))
 985               got_dot = got_e = 1;
 986             /* This test does not include !hex, because a '.' always indicates
 987                a decimal floating point number regardless of the radix.  */
 988             else if (!got_dot && *p == '.')
 989               got_dot = 1;
 990             else if (got_e && (p[-1] == 'e' || p[-1] == 'E')
 991                      && (*p == '-' || *p == '+'))
 992               /* This is the sign of the exponent, not the end of the
 993                  number.  */
 994               continue;
 995             /* We will take any letters or digits.  parse_number will
 996                complain if past the radix, or if L or U are not final.  */
 997             else if ((*p < '0' || *p > '9')
 998                      && ((*p < 'a' || *p > 'z')
 999                                   && (*p < 'A' || *p > 'Z')))
1000               break;
1001           }
1002         toktype = parse_number (tokstart, p - tokstart, got_dot|got_e, &yylval);
1003         if (toktype == ERROR)
1004           {
1005             char *err_copy = (char *) alloca (p - tokstart + 1);
1006
1007             memcpy (err_copy, tokstart, p - tokstart);
1008             err_copy[p - tokstart] = 0;
1009             error (_("Invalid number \"%s\""), err_copy);
1010           }
1011         lexptr = p;
1012         return toktype;
1013       }
1014
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     case '[':
1028     case ']':
1029     case '?':
1030     case ':':
1031     case '=':
1032     case '{':
1033     case '}':
1034     symbol:
1035       lexptr++;
1036       return c;
1037
1038     case '"':
1039
1040       /* Build the gdb internal form of the input string in tempbuf,
1041          translating any standard C escape forms seen.  Note that the
1042          buffer is null byte terminated *only* for the convenience of
1043          debugging gdb itself and printing the buffer contents when
1044          the buffer contains no embedded nulls.  Gdb does not depend
1045          upon the buffer being null byte terminated, it uses the length
1046          string instead.  This allows gdb to handle C strings (as well
1047          as strings in other languages) with embedded null bytes */
1048
1049       tokptr = ++tokstart;
1050       tempbufindex = 0;
1051
1052       do {
1053         /* Grow the static temp buffer if necessary, including allocating
1054            the first one on demand. */
1055         if (tempbufindex + 1 >= tempbufsize)
1056           {
1057             tempbuf = (char *) realloc (tempbuf, tempbufsize += 64);
1058           }
1059         switch (*tokptr)
1060           {
1061           case '\0':
1062           case '"':
1063             /* Do nothing, loop will terminate. */
1064             break;
1065           case '\\':
1066             tokptr++;
1067             c = parse_escape (&tokptr);
1068             if (c == -1)
1069               {
1070                 continue;
1071               }
1072             tempbuf[tempbufindex++] = c;
1073             break;
1074           default:
1075             tempbuf[tempbufindex++] = *tokptr++;
1076             break;
1077           }
1078       } while ((*tokptr != '"') && (*tokptr != '\0'));
1079       if (*tokptr++ != '"')
1080         {
1081           error (_("Unterminated string in expression"));
1082         }
1083       tempbuf[tempbufindex] = '\0';     /* See note above */
1084       yylval.sval.ptr = tempbuf;
1085       yylval.sval.length = tempbufindex;
1086       lexptr = tokptr;
1087       return (STRING_LITERAL);
1088     }
1089
1090   if (!(c == '_' || c == '$'
1091         || (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z')))
1092     /* We must have come across a bad character (e.g. ';').  */
1093     error (_("Invalid character '%c' in expression"), c);
1094
1095   /* It's a name.  See how long it is.  */
1096   namelen = 0;
1097   for (c = tokstart[namelen];
1098        (c == '_'
1099         || c == '$'
1100         || (c >= '0' && c <= '9')
1101         || (c >= 'a' && c <= 'z')
1102         || (c >= 'A' && c <= 'Z')
1103         || c == '<');
1104        )
1105     {
1106       if (c == '<')
1107         {
1108           int i = namelen;
1109           while (tokstart[++i] && tokstart[i] != '>');
1110           if (tokstart[i] == '>')
1111             namelen = i;
1112         }
1113        c = tokstart[++namelen];
1114      }
1115
1116   /* The token "if" terminates the expression and is NOT
1117      removed from the input stream.  */
1118   if (namelen == 2 && tokstart[0] == 'i' && tokstart[1] == 'f')
1119     {
1120       return 0;
1121     }
1122
1123   lexptr += namelen;
1124
1125   tryname:
1126
1127   /* Catch specific keywords.  Should be done with a data structure.  */
1128   switch (namelen)
1129     {
1130     case 7:
1131       if (DEPRECATED_STREQN (tokstart, "boolean", 7))
1132         return BOOLEAN;
1133       break;
1134     case 6:
1135       if (DEPRECATED_STREQN (tokstart, "double", 6))
1136         return DOUBLE;
1137       break;
1138     case 5:
1139       if (DEPRECATED_STREQN (tokstart, "short", 5))
1140         return SHORT;
1141       if (DEPRECATED_STREQN (tokstart, "false", 5))
1142         {
1143           yylval.lval = 0;
1144           return BOOLEAN_LITERAL;
1145         }
1146       if (DEPRECATED_STREQN (tokstart, "super", 5))
1147         return SUPER;
1148       if (DEPRECATED_STREQN (tokstart, "float", 5))
1149         return FLOAT;
1150       break;
1151     case 4:
1152       if (DEPRECATED_STREQN (tokstart, "long", 4))
1153         return LONG;
1154       if (DEPRECATED_STREQN (tokstart, "byte", 4))
1155         return BYTE;
1156       if (DEPRECATED_STREQN (tokstart, "char", 4))
1157         return CHAR;
1158       if (DEPRECATED_STREQN (tokstart, "true", 4))
1159         {
1160           yylval.lval = 1;
1161           return BOOLEAN_LITERAL;
1162         }
1163       break;
1164     case 3:
1165       if (strncmp (tokstart, "int", 3) == 0)
1166         return INT;
1167       if (strncmp (tokstart, "new", 3) == 0)
1168         return NEW;
1169       break;
1170     default:
1171       break;
1172     }
1173
1174   yylval.sval.ptr = tokstart;
1175   yylval.sval.length = namelen;
1176
1177   if (*tokstart == '$')
1178     {
1179       write_dollar_variable (yylval.sval);
1180       return VARIABLE;
1181     }
1182
1183   /* Input names that aren't symbols but ARE valid hex numbers,
1184      when the input radix permits them, can be names or numbers
1185      depending on the parse.  Note we support radixes > 16 here.  */
1186   if (((tokstart[0] >= 'a' && tokstart[0] < 'a' + input_radix - 10) ||
1187        (tokstart[0] >= 'A' && tokstart[0] < 'A' + input_radix - 10)))
1188     {
1189       YYSTYPE newlval;  /* Its value is ignored.  */
1190       int hextype = parse_number (tokstart, namelen, 0, &newlval);
1191       if (hextype == INTEGER_LITERAL)
1192         return NAME_OR_INT;
1193     }
1194   return IDENTIFIER;
1195 }
1196
1197 void
1198 yyerror (msg)
1199      char *msg;
1200 {
1201   if (prev_lexptr)
1202     lexptr = prev_lexptr;
1203
1204   if (msg)
1205     error (_("%s: near `%s'"), msg, lexptr);
1206   else
1207     error (_("error in expression, near `%s'"), lexptr);
1208 }
1209
1210 static struct type *
1211 java_type_from_name (name)
1212      struct stoken name;
1213
1214 {
1215   char *tmp = copy_name (name);
1216   struct type *typ = java_lookup_class (tmp);
1217   if (typ == NULL || TYPE_CODE (typ) != TYPE_CODE_STRUCT)
1218     error (_("No class named `%s'"), tmp);
1219   return typ;
1220 }
1221
1222 /* If NAME is a valid variable name in this scope, push it and return 1.
1223    Otherwise, return 0. */
1224
1225 static int
1226 push_variable (struct stoken name)
1227 {
1228   char *tmp = copy_name (name);
1229   int is_a_field_of_this = 0;
1230   struct symbol *sym;
1231   sym = lookup_symbol (tmp, expression_context_block, VAR_DOMAIN,
1232                        &is_a_field_of_this, (struct symtab **) NULL);
1233   if (sym && SYMBOL_CLASS (sym) != LOC_TYPEDEF)
1234     {
1235       if (symbol_read_needs_frame (sym))
1236         {
1237           if (innermost_block == 0 ||
1238               contained_in (block_found, innermost_block))
1239             innermost_block = block_found;
1240         }
1241
1242       write_exp_elt_opcode (OP_VAR_VALUE);
1243       /* We want to use the selected frame, not another more inner frame
1244          which happens to be in the same block.  */
1245       write_exp_elt_block (NULL);
1246       write_exp_elt_sym (sym);
1247       write_exp_elt_opcode (OP_VAR_VALUE);
1248       return 1;
1249     }
1250   if (is_a_field_of_this)
1251     {
1252       /* it hangs off of `this'.  Must not inadvertently convert from a
1253          method call to data ref.  */
1254       if (innermost_block == 0 ||
1255           contained_in (block_found, innermost_block))
1256         innermost_block = block_found;
1257       write_exp_elt_opcode (OP_THIS);
1258       write_exp_elt_opcode (OP_THIS);
1259       write_exp_elt_opcode (STRUCTOP_PTR);
1260       write_exp_string (name);
1261       write_exp_elt_opcode (STRUCTOP_PTR);
1262       return 1;
1263     }
1264   return 0;
1265 }
1266
1267 /* Assuming a reference expression has been pushed, emit the
1268    STRUCTOP_STRUCT ops to access the field named NAME.  If NAME is a
1269    qualified name (has '.'), generate a field access for each part. */
1270
1271 static void
1272 push_fieldnames (name)
1273      struct stoken name;
1274 {
1275   int i;
1276   struct stoken token;
1277   token.ptr = name.ptr;
1278   for (i = 0;  ;  i++)
1279     {
1280       if (i == name.length || name.ptr[i] == '.')
1281         {
1282           /* token.ptr is start of current field name. */
1283           token.length = &name.ptr[i] - token.ptr;
1284           write_exp_elt_opcode (STRUCTOP_STRUCT);
1285           write_exp_string (token);
1286           write_exp_elt_opcode (STRUCTOP_STRUCT);
1287           token.ptr += token.length + 1;
1288         }
1289       if (i >= name.length)
1290         break;
1291     }
1292 }
1293
1294 /* Helper routine for push_expression_name.
1295    Handle a qualified name, where DOT_INDEX is the index of the first '.' */
1296
1297 static void
1298 push_qualified_expression_name (struct stoken name, int dot_index)
1299 {
1300   struct stoken token;
1301   char *tmp;
1302   struct type *typ;
1303
1304   token.ptr = name.ptr;
1305   token.length = dot_index;
1306
1307   if (push_variable (token))
1308     {
1309       token.ptr = name.ptr + dot_index + 1;
1310       token.length = name.length - dot_index - 1;
1311       push_fieldnames (token);
1312       return;
1313     }
1314
1315   token.ptr = name.ptr;
1316   for (;;)
1317     {
1318       token.length = dot_index;
1319       tmp = copy_name (token);
1320       typ = java_lookup_class (tmp);
1321       if (typ != NULL)
1322         {
1323           if (dot_index == name.length)
1324             {
1325               write_exp_elt_opcode(OP_TYPE);
1326               write_exp_elt_type(typ);
1327               write_exp_elt_opcode(OP_TYPE);
1328               return;
1329             }
1330           dot_index++;  /* Skip '.' */
1331           name.ptr += dot_index;
1332           name.length -= dot_index;
1333           dot_index = 0;
1334           while (dot_index < name.length && name.ptr[dot_index] != '.')
1335             dot_index++;
1336           token.ptr = name.ptr;
1337           token.length = dot_index;
1338           write_exp_elt_opcode (OP_SCOPE);
1339           write_exp_elt_type (typ);
1340           write_exp_string (token);
1341           write_exp_elt_opcode (OP_SCOPE);
1342           if (dot_index < name.length)
1343             {
1344               dot_index++;
1345               name.ptr += dot_index;
1346               name.length -= dot_index;
1347               push_fieldnames (name);
1348             }
1349           return;
1350         }
1351       else if (dot_index >= name.length)
1352         break;
1353       dot_index++;  /* Skip '.' */
1354       while (dot_index < name.length && name.ptr[dot_index] != '.')
1355         dot_index++;
1356     }
1357   error (_("unknown type `%.*s'"), name.length, name.ptr);
1358 }
1359
1360 /* Handle Name in an expression (or LHS).
1361    Handle VAR, TYPE, TYPE.FIELD1....FIELDN and VAR.FIELD1....FIELDN. */
1362
1363 static void
1364 push_expression_name (name)
1365      struct stoken name;
1366 {
1367   char *tmp;
1368   struct type *typ;
1369   char *ptr;
1370   int i;
1371
1372   for (i = 0;  i < name.length;  i++)
1373     {
1374       if (name.ptr[i] == '.')
1375         {
1376           /* It's a Qualified Expression Name. */
1377           push_qualified_expression_name (name, i);
1378           return;
1379         }
1380     }
1381
1382   /* It's a Simple Expression Name. */
1383
1384   if (push_variable (name))
1385     return;
1386   tmp = copy_name (name);
1387   typ = java_lookup_class (tmp);
1388   if (typ != NULL)
1389     {
1390       write_exp_elt_opcode(OP_TYPE);
1391       write_exp_elt_type(typ);
1392       write_exp_elt_opcode(OP_TYPE);
1393     }
1394   else
1395     {
1396       struct minimal_symbol *msymbol;
1397
1398       msymbol = lookup_minimal_symbol (tmp, NULL, NULL);
1399       if (msymbol != NULL)
1400         {
1401           write_exp_msymbol (msymbol,
1402                              lookup_function_type (builtin_type_int),
1403                              builtin_type_int);
1404         }
1405       else if (!have_full_symbols () && !have_partial_symbols ())
1406         error (_("No symbol table is loaded.  Use the \"file\" command"));
1407       else
1408         error (_("No symbol \"%s\" in current context"), tmp);
1409     }
1410
1411 }
1412
1413
1414 /* The following two routines, copy_exp and insert_exp, aren't specific to
1415    Java, so they could go in parse.c, but their only purpose is to support
1416    the parsing kludges we use in this file, so maybe it's best to isolate
1417    them here.  */
1418
1419 /* Copy the expression whose last element is at index ENDPOS - 1 in EXPR
1420    into a freshly malloc'ed struct expression.  Its language_defn is set
1421    to null.  */
1422 static struct expression *
1423 copy_exp (expr, endpos)
1424      struct expression *expr;
1425      int endpos;
1426 {
1427   int len = length_of_subexp (expr, endpos);
1428   struct expression *new
1429     = (struct expression *) malloc (sizeof (*new) + EXP_ELEM_TO_BYTES (len));
1430   new->nelts = len;
1431   memcpy (new->elts, expr->elts + endpos - len, EXP_ELEM_TO_BYTES (len));
1432   new->language_defn = 0;
1433
1434   return new;
1435 }
1436
1437 /* Insert the expression NEW into the current expression (expout) at POS.  */
1438 static void
1439 insert_exp (pos, new)
1440      int pos;
1441      struct expression *new;
1442 {
1443   int newlen = new->nelts;
1444
1445   /* Grow expout if necessary.  In this function's only use at present,
1446      this should never be necessary.  */
1447   if (expout_ptr + newlen > expout_size)
1448     {
1449       expout_size = max (expout_size * 2, expout_ptr + newlen + 10);
1450       expout = (struct expression *)
1451         realloc ((char *) expout, (sizeof (struct expression)
1452                                     + EXP_ELEM_TO_BYTES (expout_size)));
1453     }
1454
1455   {
1456     int i;
1457
1458     for (i = expout_ptr - 1; i >= pos; i--)
1459       expout->elts[i + newlen] = expout->elts[i];
1460   }
1461
1462   memcpy (expout->elts + pos, new->elts, EXP_ELEM_TO_BYTES (newlen));
1463   expout_ptr += newlen;
1464 }