gdb/expprint.c

   1 /* Print in infix form a struct expression.
   2
   3    Copyright (C) 1986, 1988-1989, 1991-2000, 2003, 2007-2012 Free
   4    Software Foundation, Inc.
   5
   6    This file is part of GDB.
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  20
  21 #include "defs.h"
  22 #include "symtab.h"
  23 #include "gdbtypes.h"
  24 #include "expression.h"
  25 #include "value.h"
  26 #include "language.h"
  27 #include "parser-defs.h"
  28 #include "user-regs.h"          /* For user_reg_map_regnum_to_name.  */
  29 #include "target.h"
  30 #include "gdb_string.h"
  31 #include "block.h"
  32 #include "objfiles.h"
  33 #include "gdb_assert.h"
  34 #include "valprint.h"
  35
  36 #ifdef HAVE_CTYPE_H
  37 #include <ctype.h>
  38 #endif
  39
  40 void
  41 print_expression (struct expression *exp, struct ui_file *stream)
  42 {
  43   int pc = 0;
  44
  45   print_subexp (exp, &pc, stream, PREC_NULL);
  46 }
  47
  48 /* Print the subexpression of EXP that starts in position POS, on STREAM.
  49    PREC is the precedence of the surrounding operator;
  50    if the precedence of the main operator of this subexpression is less,
  51    parentheses are needed here.  */
  52
  53 void
  54 print_subexp (struct expression *exp, int *pos,
  55               struct ui_file *stream, enum precedence prec)
  56 {
  57   exp->language_defn->la_exp_desc->print_subexp (exp, pos, stream, prec);
  58 }
  59
  60 /* Standard implementation of print_subexp for use in language_defn
  61    vectors.  */
  62 void
  63 print_subexp_standard (struct expression *exp, int *pos,
  64                        struct ui_file *stream, enum precedence prec)
  65 {
  66   unsigned tem;
  67   const struct op_print *op_print_tab;
  68   int pc;
  69   unsigned nargs;
  70   char *op_str;
  71   int assign_modify = 0;
  72   enum exp_opcode opcode;
  73   enum precedence myprec = PREC_NULL;
  74   /* Set to 1 for a right-associative operator.  */
  75   int assoc = 0;
  76   struct value *val;
  77   char *tempstr = NULL;
  78
  79   op_print_tab = exp->language_defn->la_op_print_tab;
  80   pc = (*pos)++;
  81   opcode = exp->elts[pc].opcode;
  82   switch (opcode)
  83     {
  84       /* Common ops */
  85
  86     case OP_SCOPE:
  87       myprec = PREC_PREFIX;
  88       assoc = 0;
  89       fputs_filtered (type_name_no_tag (exp->elts[pc + 1].type), stream);
  90       fputs_filtered ("::", stream);
  91       nargs = longest_to_int (exp->elts[pc + 2].longconst);
  92       (*pos) += 4 + BYTES_TO_EXP_ELEM (nargs + 1);
  93       fputs_filtered (&exp->elts[pc + 3].string, stream);
  94       return;
  95
  96     case OP_LONG:
  97       {
  98         struct value_print_options opts;
  99
 100         get_raw_print_options (&opts);
 101         (*pos) += 3;
 102         value_print (value_from_longest (exp->elts[pc + 1].type,
 103                                          exp->elts[pc + 2].longconst),
 104                      stream, &opts);
 105       }
 106       return;
 107
 108     case OP_DOUBLE:
 109       {
 110         struct value_print_options opts;
 111
 112         get_raw_print_options (&opts);
 113         (*pos) += 3;
 114         value_print (value_from_double (exp->elts[pc + 1].type,
 115                                         exp->elts[pc + 2].doubleconst),
 116                      stream, &opts);
 117       }
 118       return;
 119
 120     case OP_VAR_VALUE:
 121       {
 122         struct block *b;
 123
 124         (*pos) += 3;
 125         b = exp->elts[pc + 1].block;
 126         if (b != NULL
 127             && BLOCK_FUNCTION (b) != NULL
 128             && SYMBOL_PRINT_NAME (BLOCK_FUNCTION (b)) != NULL)
 129           {
 130             fputs_filtered (SYMBOL_PRINT_NAME (BLOCK_FUNCTION (b)), stream);
 131             fputs_filtered ("::", stream);
 132           }
 133         fputs_filtered (SYMBOL_PRINT_NAME (exp->elts[pc + 2].symbol), stream);
 134       }
 135       return;
 136
 137     case OP_VAR_ENTRY_VALUE:
 138       {
 139         (*pos) += 2;
 140         fprintf_filtered (stream, "%s@entry",
 141                           SYMBOL_PRINT_NAME (exp->elts[pc + 1].symbol));
 142       }
 143       return;
 144
 145     case OP_LAST:
 146       (*pos) += 2;
 147       fprintf_filtered (stream, "$%d",
 148                         longest_to_int (exp->elts[pc + 1].longconst));
 149       return;
 150
 151     case OP_REGISTER:
 152       {
 153         const char *name = &exp->elts[pc + 2].string;
 154
 155         (*pos) += 3 + BYTES_TO_EXP_ELEM (exp->elts[pc + 1].longconst + 1);
 156         fprintf_filtered (stream, "$%s", name);
 157         return;
 158       }
 159
 160     case OP_BOOL:
 161       (*pos) += 2;
 162       fprintf_filtered (stream, "%s",
 163                         longest_to_int (exp->elts[pc + 1].longconst)
 164                         ? "TRUE" : "FALSE");
 165       return;
 166
 167     case OP_INTERNALVAR:
 168       (*pos) += 2;
 169       fprintf_filtered (stream, "$%s",
 170                         internalvar_name (exp->elts[pc + 1].internalvar));
 171       return;
 172
 173     case OP_FUNCALL:
 174       (*pos) += 2;
 175       nargs = longest_to_int (exp->elts[pc + 1].longconst);
 176       print_subexp (exp, pos, stream, PREC_SUFFIX);
 177       fputs_filtered (" (", stream);
 178       for (tem = 0; tem < nargs; tem++)
 179         {
 180           if (tem != 0)
 181             fputs_filtered (", ", stream);
 182           print_subexp (exp, pos, stream, PREC_ABOVE_COMMA);
 183         }
 184       fputs_filtered (")", stream);
 185       return;
 186
 187     case OP_NAME:
 188       nargs = longest_to_int (exp->elts[pc + 1].longconst);
 189       (*pos) += 3 + BYTES_TO_EXP_ELEM (nargs + 1);
 190       fputs_filtered (&exp->elts[pc + 2].string, stream);
 191       return;
 192
 193     case OP_STRING:
 194       {
 195         struct value_print_options opts;
 196
 197         nargs = longest_to_int (exp->elts[pc + 1].longconst);
 198         (*pos) += 3 + BYTES_TO_EXP_ELEM (nargs + 1);
 199         /* LA_PRINT_STRING will print using the current repeat count threshold.
 200            If necessary, we can temporarily set it to zero, or pass it as an
 201            additional parameter to LA_PRINT_STRING.  -fnf */
 202         get_user_print_options (&opts);
 203         LA_PRINT_STRING (stream, builtin_type (exp->gdbarch)->builtin_char,
 204                          &exp->elts[pc + 2].string, nargs, NULL, 0, &opts);
 205       }
 206       return;
 207
 208     case OP_BITSTRING:
 209       nargs = longest_to_int (exp->elts[pc + 1].longconst);
 210       (*pos)
 211         += 3 + BYTES_TO_EXP_ELEM ((nargs + HOST_CHAR_BIT - 1) / HOST_CHAR_BIT);
 212       fprintf_unfiltered (stream, "B'<unimplemented>'");
 213       return;
 214
 215     case OP_OBJC_NSSTRING:      /* Objective-C Foundation Class
 216                                    NSString constant.  */
 217       {
 218         struct value_print_options opts;
 219
 220         nargs = longest_to_int (exp->elts[pc + 1].longconst);
 221         (*pos) += 3 + BYTES_TO_EXP_ELEM (nargs + 1);
 222         fputs_filtered ("@\"", stream);
 223         get_user_print_options (&opts);
 224         LA_PRINT_STRING (stream, builtin_type (exp->gdbarch)->builtin_char,
 225                          &exp->elts[pc + 2].string, nargs, NULL, 0, &opts);
 226         fputs_filtered ("\"", stream);
 227       }
 228       return;
 229
 230     case OP_OBJC_MSGCALL:
 231       {                 /* Objective C message (method) call.  */
 232         char *selector;
 233
 234         (*pos) += 3;
 235         nargs = longest_to_int (exp->elts[pc + 2].longconst);
 236         fprintf_unfiltered (stream, "[");
 237         print_subexp (exp, pos, stream, PREC_SUFFIX);
 238         if (0 == target_read_string (exp->elts[pc + 1].longconst,
 239                                      &selector, 1024, NULL))
 240           {
 241             error (_("bad selector"));
 242             return;
 243           }
 244         if (nargs)
 245           {
 246             char *s, *nextS;
 247
 248             s = alloca (strlen (selector) + 1);
 249             strcpy (s, selector);
 250             for (tem = 0; tem < nargs; tem++)
 251               {
 252                 nextS = strchr (s, ':');
 253                 gdb_assert (nextS);     /* Make sure we found ':'.  */
 254                 *nextS = '\0';
 255                 fprintf_unfiltered (stream, " %s: ", s);
 256                 s = nextS + 1;
 257                 print_subexp (exp, pos, stream, PREC_ABOVE_COMMA);
 258               }
 259           }
 260         else
 261           {
 262             fprintf_unfiltered (stream, " %s", selector);
 263           }
 264         fprintf_unfiltered (stream, "]");
 265         /* "selector" was malloc'd by target_read_string.  Free it.  */
 266         xfree (selector);
 267         return;
 268       }
 269
 270     case OP_ARRAY:
 271       (*pos) += 3;
 272       nargs = longest_to_int (exp->elts[pc + 2].longconst);
 273       nargs -= longest_to_int (exp->elts[pc + 1].longconst);
 274       nargs++;
 275       tem = 0;
 276       if (exp->elts[pc + 4].opcode == OP_LONG
 277           && exp->elts[pc + 5].type
 278              == builtin_type (exp->gdbarch)->builtin_char
 279           && exp->language_defn->la_language == language_c)
 280         {
 281           /* Attempt to print C character arrays using string syntax.
 282              Walk through the args, picking up one character from each
 283              of the OP_LONG expression elements.  If any array element
 284              does not match our expection of what we should find for
 285              a simple string, revert back to array printing.  Note that
 286              the last expression element is an explicit null terminator
 287              byte, which doesn't get printed.  */
 288           tempstr = alloca (nargs);
 289           pc += 4;
 290           while (tem < nargs)
 291             {
 292               if (exp->elts[pc].opcode != OP_LONG
 293                   || exp->elts[pc + 1].type
 294                      != builtin_type (exp->gdbarch)->builtin_char)
 295                 {
 296                   /* Not a simple array of char, use regular array
 297                      printing.  */
 298                   tem = 0;
 299                   break;
 300                 }
 301               else
 302                 {
 303                   tempstr[tem++] =
 304                     longest_to_int (exp->elts[pc + 2].longconst);
 305                   pc += 4;
 306                 }
 307             }
 308         }
 309       if (tem > 0)
 310         {
 311           struct value_print_options opts;
 312
 313           get_user_print_options (&opts);
 314           LA_PRINT_STRING (stream, builtin_type (exp->gdbarch)->builtin_char,
 315                            tempstr, nargs - 1, NULL, 0, &opts);
 316           (*pos) = pc;
 317         }
 318       else
 319         {
 320           fputs_filtered (" {", stream);
 321           for (tem = 0; tem < nargs; tem++)
 322             {
 323               if (tem != 0)
 324                 {
 325                   fputs_filtered (", ", stream);
 326                 }
 327               print_subexp (exp, pos, stream, PREC_ABOVE_COMMA);
 328             }
 329           fputs_filtered ("}", stream);
 330         }
 331       return;
 332
 333     case OP_LABELED:
 334       tem = longest_to_int (exp->elts[pc + 1].longconst);
 335       (*pos) += 3 + BYTES_TO_EXP_ELEM (tem + 1);
 336       /* Gcc support both these syntaxes.  Unsure which is preferred.  */
 337 #if 1
 338       fputs_filtered (&exp->elts[pc + 2].string, stream);
 339       fputs_filtered (": ", stream);
 340 #else
 341       fputs_filtered (".", stream);
 342       fputs_filtered (&exp->elts[pc + 2].string, stream);
 343       fputs_filtered ("=", stream);
 344 #endif
 345       print_subexp (exp, pos, stream, PREC_SUFFIX);
 346       return;
 347
 348     case TERNOP_COND:
 349       if ((int) prec > (int) PREC_COMMA)
 350         fputs_filtered ("(", stream);
 351       /* Print the subexpressions, forcing parentheses
 352          around any binary operations within them.
 353          This is more parentheses than are strictly necessary,
 354          but it looks clearer.  */
 355       print_subexp (exp, pos, stream, PREC_HYPER);
 356       fputs_filtered (" ? ", stream);
 357       print_subexp (exp, pos, stream, PREC_HYPER);
 358       fputs_filtered (" : ", stream);
 359       print_subexp (exp, pos, stream, PREC_HYPER);
 360       if ((int) prec > (int) PREC_COMMA)
 361         fputs_filtered (")", stream);
 362       return;
 363
 364     case TERNOP_SLICE:
 365     case TERNOP_SLICE_COUNT:
 366       print_subexp (exp, pos, stream, PREC_SUFFIX);
 367       fputs_filtered ("(", stream);
 368       print_subexp (exp, pos, stream, PREC_ABOVE_COMMA);
 369       fputs_filtered (opcode == TERNOP_SLICE ? " : " : " UP ", stream);
 370       print_subexp (exp, pos, stream, PREC_ABOVE_COMMA);
 371       fputs_filtered (")", stream);
 372       return;
 373
 374     case STRUCTOP_STRUCT:
 375       tem = longest_to_int (exp->elts[pc + 1].longconst);
 376       (*pos) += 3 + BYTES_TO_EXP_ELEM (tem + 1);
 377       print_subexp (exp, pos, stream, PREC_SUFFIX);
 378       fputs_filtered (".", stream);
 379       fputs_filtered (&exp->elts[pc + 2].string, stream);
 380       return;
 381
 382       /* Will not occur for Modula-2.  */
 383     case STRUCTOP_PTR:
 384       tem = longest_to_int (exp->elts[pc + 1].longconst);
 385       (*pos) += 3 + BYTES_TO_EXP_ELEM (tem + 1);
 386       print_subexp (exp, pos, stream, PREC_SUFFIX);
 387       fputs_filtered ("->", stream);
 388       fputs_filtered (&exp->elts[pc + 2].string, stream);
 389       return;
 390
 391     case STRUCTOP_MEMBER:
 392       print_subexp (exp, pos, stream, PREC_SUFFIX);
 393       fputs_filtered (".*", stream);
 394       print_subexp (exp, pos, stream, PREC_SUFFIX);
 395       return;
 396
 397     case STRUCTOP_MPTR:
 398       print_subexp (exp, pos, stream, PREC_SUFFIX);
 399       fputs_filtered ("->*", stream);
 400       print_subexp (exp, pos, stream, PREC_SUFFIX);
 401       return;
 402
 403     case BINOP_SUBSCRIPT:
 404       print_subexp (exp, pos, stream, PREC_SUFFIX);
 405       fputs_filtered ("[", stream);
 406       print_subexp (exp, pos, stream, PREC_ABOVE_COMMA);
 407       fputs_filtered ("]", stream);
 408       return;
 409
 410     case UNOP_POSTINCREMENT:
 411       print_subexp (exp, pos, stream, PREC_SUFFIX);
 412       fputs_filtered ("++", stream);
 413       return;
 414
 415     case UNOP_POSTDECREMENT:
 416       print_subexp (exp, pos, stream, PREC_SUFFIX);
 417       fputs_filtered ("--", stream);
 418       return;
 419
 420     case UNOP_CAST:
 421       (*pos) += 2;
 422       if ((int) prec > (int) PREC_PREFIX)
 423         fputs_filtered ("(", stream);
 424       fputs_filtered ("(", stream);
 425       type_print (exp->elts[pc + 1].type, "", stream, 0);
 426       fputs_filtered (") ", stream);
 427       print_subexp (exp, pos, stream, PREC_PREFIX);
 428       if ((int) prec > (int) PREC_PREFIX)
 429         fputs_filtered (")", stream);
 430       return;
 431
 432     case UNOP_DYNAMIC_CAST:
 433     case UNOP_REINTERPRET_CAST:
 434       fputs_filtered (opcode == UNOP_DYNAMIC_CAST ? "dynamic_cast"
 435                       : "reinterpret_cast", stream);
 436       fputs_filtered ("<", stream);
 437       (*pos) += 2;
 438       type_print (exp->elts[pc + 1].type, "", stream, 0);
 439       fputs_filtered ("> (", stream);
 440       print_subexp (exp, pos, stream, PREC_PREFIX);
 441       fputs_filtered (")", stream);
 442       return;
 443
 444     case UNOP_MEMVAL:
 445       (*pos) += 2;
 446       if ((int) prec > (int) PREC_PREFIX)
 447         fputs_filtered ("(", stream);
 448       if (TYPE_CODE (exp->elts[pc + 1].type) == TYPE_CODE_FUNC
 449           && exp->elts[pc + 3].opcode == OP_LONG)
 450         {
 451           struct value_print_options opts;
 452
 453           /* We have a minimal symbol fn, probably.  It's encoded
 454              as a UNOP_MEMVAL (function-type) of an OP_LONG (int, address).
 455              Swallow the OP_LONG (including both its opcodes); ignore
 456              its type; print the value in the type of the MEMVAL.  */
 457           (*pos) += 4;
 458           val = value_at_lazy (exp->elts[pc + 1].type,
 459                                (CORE_ADDR) exp->elts[pc + 5].longconst);
 460           get_raw_print_options (&opts);
 461           value_print (val, stream, &opts);
 462         }
 463       else
 464         {
 465           fputs_filtered ("{", stream);
 466           type_print (exp->elts[pc + 1].type, "", stream, 0);
 467           fputs_filtered ("} ", stream);
 468           print_subexp (exp, pos, stream, PREC_PREFIX);
 469         }
 470       if ((int) prec > (int) PREC_PREFIX)
 471         fputs_filtered (")", stream);
 472       return;
 473
 474     case UNOP_MEMVAL_TLS:
 475       (*pos) += 3;
 476       if ((int) prec > (int) PREC_PREFIX)
 477         fputs_filtered ("(", stream);
 478       fputs_filtered ("{", stream);
 479       type_print (exp->elts[pc + 2].type, "", stream, 0);
 480       fputs_filtered ("} ", stream);
 481       print_subexp (exp, pos, stream, PREC_PREFIX);
 482       if ((int) prec > (int) PREC_PREFIX)
 483         fputs_filtered (")", stream);
 484       return;
 485
 486     case BINOP_ASSIGN_MODIFY:
 487       opcode = exp->elts[pc + 1].opcode;
 488       (*pos) += 2;
 489       myprec = PREC_ASSIGN;
 490       assoc = 1;
 491       assign_modify = 1;
 492       op_str = "???";
 493       for (tem = 0; op_print_tab[tem].opcode != OP_NULL; tem++)
 494         if (op_print_tab[tem].opcode == opcode)
 495           {
 496             op_str = op_print_tab[tem].string;
 497             break;
 498           }
 499       if (op_print_tab[tem].opcode != opcode)
 500         /* Not found; don't try to keep going because we don't know how
 501            to interpret further elements.  */
 502         error (_("Invalid expression"));
 503       break;
 504
 505       /* C++ ops */
 506
 507     case OP_THIS:
 508       ++(*pos);
 509       if (exp->language_defn->la_name_of_this)
 510         fputs_filtered (exp->language_defn->la_name_of_this, stream);
 511       else
 512         fprintf_filtered (stream, _("<language %s has no 'this'>"),
 513                           exp->language_defn->la_name);
 514       return;
 515
 516       /* Modula-2 ops */
 517
 518     case MULTI_SUBSCRIPT:
 519       (*pos) += 2;
 520       nargs = longest_to_int (exp->elts[pc + 1].longconst);
 521       print_subexp (exp, pos, stream, PREC_SUFFIX);
 522       fprintf_unfiltered (stream, " [");
 523       for (tem = 0; tem < nargs; tem++)
 524         {
 525           if (tem != 0)
 526             fprintf_unfiltered (stream, ", ");
 527           print_subexp (exp, pos, stream, PREC_ABOVE_COMMA);
 528         }
 529       fprintf_unfiltered (stream, "]");
 530       return;
 531
 532     case BINOP_VAL:
 533       (*pos) += 2;
 534       fprintf_unfiltered (stream, "VAL(");
 535       type_print (exp->elts[pc + 1].type, "", stream, 0);
 536       fprintf_unfiltered (stream, ",");
 537       print_subexp (exp, pos, stream, PREC_PREFIX);
 538       fprintf_unfiltered (stream, ")");
 539       return;
 540
 541     case TYPE_INSTANCE:
 542       {
 543         LONGEST count = exp->elts[pc + 1].longconst;
 544
 545         /* The COUNT.  */
 546         (*pos)++;
 547         fputs_unfiltered ("TypesInstance(", stream);
 548         while (count-- > 0)
 549           {
 550             type_print (exp->elts[(*pos)++].type, "", stream, 0);
 551             if (count > 0)
 552               fputs_unfiltered (",", stream);
 553           }
 554         fputs_unfiltered (",", stream);
 555         /* Ending COUNT and ending TYPE_INSTANCE.  */
 556         (*pos) += 2;
 557         print_subexp (exp, pos, stream, PREC_PREFIX);
 558         fputs_unfiltered (")", stream);
 559         return;
 560       }
 561
 562       /* Default ops */
 563
 564     default:
 565       op_str = "???";
 566       for (tem = 0; op_print_tab[tem].opcode != OP_NULL; tem++)
 567         if (op_print_tab[tem].opcode == opcode)
 568           {
 569             op_str = op_print_tab[tem].string;
 570             myprec = op_print_tab[tem].precedence;
 571             assoc = op_print_tab[tem].right_assoc;
 572             break;
 573           }
 574       if (op_print_tab[tem].opcode != opcode)
 575         /* Not found; don't try to keep going because we don't know how
 576            to interpret further elements.  For example, this happens
 577            if opcode is OP_TYPE.  */
 578         error (_("Invalid expression"));
 579     }
 580
 581   /* Note that PREC_BUILTIN will always emit parentheses.  */
 582   if ((int) myprec < (int) prec)
 583     fputs_filtered ("(", stream);
 584   if ((int) opcode > (int) BINOP_END)
 585     {
 586       if (assoc)
 587         {
 588           /* Unary postfix operator.  */
 589           print_subexp (exp, pos, stream, PREC_SUFFIX);
 590           fputs_filtered (op_str, stream);
 591         }
 592       else
 593         {
 594           /* Unary prefix operator.  */
 595           fputs_filtered (op_str, stream);
 596           if (myprec == PREC_BUILTIN_FUNCTION)
 597             fputs_filtered ("(", stream);
 598           print_subexp (exp, pos, stream, PREC_PREFIX);
 599           if (myprec == PREC_BUILTIN_FUNCTION)
 600             fputs_filtered (")", stream);
 601         }
 602     }
 603   else
 604     {
 605       /* Binary operator.  */
 606       /* Print left operand.
 607          If operator is right-associative,
 608          increment precedence for this operand.  */
 609       print_subexp (exp, pos, stream,
 610                     (enum precedence) ((int) myprec + assoc));
 611       /* Print the operator itself.  */
 612       if (assign_modify)
 613         fprintf_filtered (stream, " %s= ", op_str);
 614       else if (op_str[0] == ',')
 615         fprintf_filtered (stream, "%s ", op_str);
 616       else
 617         fprintf_filtered (stream, " %s ", op_str);
 618       /* Print right operand.
 619          If operator is left-associative,
 620          increment precedence for this operand.  */
 621       print_subexp (exp, pos, stream,
 622                     (enum precedence) ((int) myprec + !assoc));
 623     }
 624
 625   if ((int) myprec < (int) prec)
 626     fputs_filtered (")", stream);
 627 }
 628
 629 /* Return the operator corresponding to opcode OP as
 630    a string.   NULL indicates that the opcode was not found in the
 631    current language table.  */
 632 char *
 633 op_string (enum exp_opcode op)
 634 {
 635   int tem;
 636   const struct op_print *op_print_tab;
 637
 638   op_print_tab = current_language->la_op_print_tab;
 639   for (tem = 0; op_print_tab[tem].opcode != OP_NULL; tem++)
 640     if (op_print_tab[tem].opcode == op)
 641       return op_print_tab[tem].string;
 642   return NULL;
 643 }
 644
 645 /* Support for dumping the raw data from expressions in a human readable
 646    form.  */
 647
 648 static int dump_subexp_body (struct expression *exp, struct ui_file *, int);
 649
 650 /* Name for OPCODE, when it appears in expression EXP.  */
 651
 652 char *
 653 op_name (struct expression *exp, enum exp_opcode opcode)
 654 {
 655   return exp->language_defn->la_exp_desc->op_name (opcode);
 656 }
 657
 658 /* Default name for the standard operator OPCODE (i.e., one defined in
 659    the definition of enum exp_opcode).  */
 660
 661 char *
 662 op_name_standard (enum exp_opcode opcode)
 663 {
 664   switch (opcode)
 665     {
 666     default:
 667       {
 668         static char buf[30];
 669
 670         sprintf (buf, "<unknown %d>", opcode);
 671         return buf;
 672       }
 673 #define OP(name)        \
 674     case name:          \
 675       return #name ;
 676 #include "std-operator.def"
 677 #undef OP
 678     }
 679 }
 680
 681 /* Print a raw dump of expression EXP to STREAM.
 682    NOTE, if non-NULL, is printed as extra explanatory text.  */
 683
 684 void
 685 dump_raw_expression (struct expression *exp, struct ui_file *stream,
 686                      char *note)
 687 {
 688   int elt;
 689   char *opcode_name;
 690   char *eltscan;
 691   int eltsize;
 692
 693   fprintf_filtered (stream, "Dump of expression @ ");
 694   gdb_print_host_address (exp, stream);
 695   if (note)
 696     fprintf_filtered (stream, ", %s:", note);
 697   fprintf_filtered (stream, "\n\tLanguage %s, %d elements, %ld bytes each.\n",
 698                     exp->language_defn->la_name, exp->nelts,
 699                     (long) sizeof (union exp_element));
 700   fprintf_filtered (stream, "\t%5s  %20s  %16s  %s\n", "Index", "Opcode",
 701                     "Hex Value", "String Value");
 702   for (elt = 0; elt < exp->nelts; elt++)
 703     {
 704       fprintf_filtered (stream, "\t%5d  ", elt);
 705       opcode_name = op_name (exp, exp->elts[elt].opcode);
 706
 707       fprintf_filtered (stream, "%20s  ", opcode_name);
 708       print_longest (stream, 'd', 0, exp->elts[elt].longconst);
 709       fprintf_filtered (stream, "  ");
 710
 711       for (eltscan = (char *) &exp->elts[elt],
 712            eltsize = sizeof (union exp_element);
 713            eltsize-- > 0;
 714            eltscan++)
 715         {
 716           fprintf_filtered (stream, "%c",
 717                             isprint (*eltscan) ? (*eltscan & 0xFF) : '.');
 718         }
 719       fprintf_filtered (stream, "\n");
 720     }
 721 }
 722
 723 /* Dump the subexpression of prefix expression EXP whose operator is at
 724    position ELT onto STREAM.  Returns the position of the next
 725    subexpression in EXP.  */
 726
 727 int
 728 dump_subexp (struct expression *exp, struct ui_file *stream, int elt)
 729 {
 730   static int indent = 0;
 731   int i;
 732
 733   fprintf_filtered (stream, "\n");
 734   fprintf_filtered (stream, "\t%5d  ", elt);
 735
 736   for (i = 1; i <= indent; i++)
 737     fprintf_filtered (stream, " ");
 738   indent += 2;
 739
 740   fprintf_filtered (stream, "%-20s  ", op_name (exp, exp->elts[elt].opcode));
 741
 742   elt = dump_subexp_body (exp, stream, elt);
 743
 744   indent -= 2;
 745
 746   return elt;
 747 }
 748
 749 /* Dump the operands of prefix expression EXP whose opcode is at
 750    position ELT onto STREAM.  Returns the position of the next
 751    subexpression in EXP.  */
 752
 753 static int
 754 dump_subexp_body (struct expression *exp, struct ui_file *stream, int elt)
 755 {
 756   return exp->language_defn->la_exp_desc->dump_subexp_body (exp, stream, elt);
 757 }
 758
 759 /* Default value for subexp_body in exp_descriptor vector.  */
 760
 761 int
 762 dump_subexp_body_standard (struct expression *exp,
 763                            struct ui_file *stream, int elt)
 764 {
 765   int opcode = exp->elts[elt++].opcode;
 766
 767   switch (opcode)
 768     {
 769     case TERNOP_COND:
 770     case TERNOP_SLICE:
 771     case TERNOP_SLICE_COUNT:
 772       elt = dump_subexp (exp, stream, elt);
 773       /* FALL THROUGH */
 774     case BINOP_ADD:
 775     case BINOP_SUB:
 776     case BINOP_MUL:
 777     case BINOP_DIV:
 778     case BINOP_REM:
 779     case BINOP_MOD:
 780     case BINOP_LSH:
 781     case BINOP_RSH:
 782     case BINOP_LOGICAL_AND:
 783     case BINOP_LOGICAL_OR:
 784     case BINOP_BITWISE_AND:
 785     case BINOP_BITWISE_IOR:
 786     case BINOP_BITWISE_XOR:
 787     case BINOP_EQUAL:
 788     case BINOP_NOTEQUAL:
 789     case BINOP_LESS:
 790     case BINOP_GTR:
 791     case BINOP_LEQ:
 792     case BINOP_GEQ:
 793     case BINOP_REPEAT:
 794     case BINOP_ASSIGN:
 795     case BINOP_COMMA:
 796     case BINOP_SUBSCRIPT:
 797     case BINOP_EXP:
 798     case BINOP_MIN:
 799     case BINOP_MAX:
 800     case BINOP_INTDIV:
 801     case BINOP_ASSIGN_MODIFY:
 802     case BINOP_VAL:
 803     case BINOP_CONCAT:
 804     case BINOP_IN:
 805     case BINOP_RANGE:
 806     case BINOP_END:
 807     case STRUCTOP_MEMBER:
 808     case STRUCTOP_MPTR:
 809       elt = dump_subexp (exp, stream, elt);
 810       /* FALL THROUGH */
 811     case UNOP_NEG:
 812     case UNOP_LOGICAL_NOT:
 813     case UNOP_COMPLEMENT:
 814     case UNOP_IND:
 815     case UNOP_ADDR:
 816     case UNOP_PREINCREMENT:
 817     case UNOP_POSTINCREMENT:
 818     case UNOP_PREDECREMENT:
 819     case UNOP_POSTDECREMENT:
 820     case UNOP_SIZEOF:
 821     case UNOP_PLUS:
 822     case UNOP_CAP:
 823     case UNOP_CHR:
 824     case UNOP_ORD:
 825     case UNOP_ABS:
 826     case UNOP_FLOAT:
 827     case UNOP_HIGH:
 828     case UNOP_MAX:
 829     case UNOP_MIN:
 830     case UNOP_ODD:
 831     case UNOP_TRUNC:
 832       elt = dump_subexp (exp, stream, elt);
 833       break;
 834     case OP_LONG:
 835       fprintf_filtered (stream, "Type @");
 836       gdb_print_host_address (exp->elts[elt].type, stream);
 837       fprintf_filtered (stream, " (");
 838       type_print (exp->elts[elt].type, NULL, stream, 0);
 839       fprintf_filtered (stream, "), value %ld (0x%lx)",
 840                         (long) exp->elts[elt + 1].longconst,
 841                         (long) exp->elts[elt + 1].longconst);
 842       elt += 3;
 843       break;
 844     case OP_DOUBLE:
 845       fprintf_filtered (stream, "Type @");
 846       gdb_print_host_address (exp->elts[elt].type, stream);
 847       fprintf_filtered (stream, " (");
 848       type_print (exp->elts[elt].type, NULL, stream, 0);
 849       fprintf_filtered (stream, "), value %g",
 850                         (double) exp->elts[elt + 1].doubleconst);
 851       elt += 3;
 852       break;
 853     case OP_VAR_VALUE:
 854       fprintf_filtered (stream, "Block @");
 855       gdb_print_host_address (exp->elts[elt].block, stream);
 856       fprintf_filtered (stream, ", symbol @");
 857       gdb_print_host_address (exp->elts[elt + 1].symbol, stream);
 858       fprintf_filtered (stream, " (%s)",
 859                         SYMBOL_PRINT_NAME (exp->elts[elt + 1].symbol));
 860       elt += 3;
 861       break;
 862     case OP_VAR_ENTRY_VALUE:
 863       fprintf_filtered (stream, "Entry value of symbol @");
 864       gdb_print_host_address (exp->elts[elt].symbol, stream);
 865       fprintf_filtered (stream, " (%s)",
 866                         SYMBOL_PRINT_NAME (exp->elts[elt].symbol));
 867       elt += 2;
 868       break;
 869     case OP_LAST:
 870       fprintf_filtered (stream, "History element %ld",
 871                         (long) exp->elts[elt].longconst);
 872       elt += 2;
 873       break;
 874     case OP_REGISTER:
 875       fprintf_filtered (stream, "Register $%s", &exp->elts[elt + 1].string);
 876       elt += 3 + BYTES_TO_EXP_ELEM (exp->elts[elt].longconst + 1);
 877       break;
 878     case OP_INTERNALVAR:
 879       fprintf_filtered (stream, "Internal var @");
 880       gdb_print_host_address (exp->elts[elt].internalvar, stream);
 881       fprintf_filtered (stream, " (%s)",
 882                         internalvar_name (exp->elts[elt].internalvar));
 883       elt += 2;
 884       break;
 885     case OP_FUNCALL:
 886       {
 887         int i, nargs;
 888
 889         nargs = longest_to_int (exp->elts[elt].longconst);
 890
 891         fprintf_filtered (stream, "Number of args: %d", nargs);
 892         elt += 2;
 893
 894         for (i = 1; i <= nargs + 1; i++)
 895           elt = dump_subexp (exp, stream, elt);
 896       }
 897       break;
 898     case OP_ARRAY:
 899       {
 900         int lower, upper;
 901         int i;
 902
 903         lower = longest_to_int (exp->elts[elt].longconst);
 904         upper = longest_to_int (exp->elts[elt + 1].longconst);
 905
 906         fprintf_filtered (stream, "Bounds [%d:%d]", lower, upper);
 907         elt += 3;
 908
 909         for (i = 1; i <= upper - lower + 1; i++)
 910           elt = dump_subexp (exp, stream, elt);
 911       }
 912       break;
 913     case UNOP_MEMVAL:
 914     case UNOP_CAST:
 915     case UNOP_DYNAMIC_CAST:
 916     case UNOP_REINTERPRET_CAST:
 917       fprintf_filtered (stream, "Type @");
 918       gdb_print_host_address (exp->elts[elt].type, stream);
 919       fprintf_filtered (stream, " (");
 920       type_print (exp->elts[elt].type, NULL, stream, 0);
 921       fprintf_filtered (stream, ")");
 922       elt = dump_subexp (exp, stream, elt + 2);
 923       break;
 924     case UNOP_MEMVAL_TLS:
 925       fprintf_filtered (stream, "TLS type @");
 926       gdb_print_host_address (exp->elts[elt + 1].type, stream);
 927       fprintf_filtered (stream, " (__thread /* \"%s\" */ ",
 928                         (exp->elts[elt].objfile == NULL ? "(null)"
 929                          : exp->elts[elt].objfile->name));
 930       type_print (exp->elts[elt + 1].type, NULL, stream, 0);
 931       fprintf_filtered (stream, ")");
 932       elt = dump_subexp (exp, stream, elt + 3);
 933       break;
 934     case OP_TYPE:
 935       fprintf_filtered (stream, "Type @");
 936       gdb_print_host_address (exp->elts[elt].type, stream);
 937       fprintf_filtered (stream, " (");
 938       type_print (exp->elts[elt].type, NULL, stream, 0);
 939       fprintf_filtered (stream, ")");
 940       elt += 2;
 941       break;
 942     case STRUCTOP_STRUCT:
 943     case STRUCTOP_PTR:
 944       {
 945         char *elem_name;
 946         int len;
 947
 948         len = longest_to_int (exp->elts[elt].longconst);
 949         elem_name = &exp->elts[elt + 1].string;
 950
 951         fprintf_filtered (stream, "Element name: `%.*s'", len, elem_name);
 952         elt = dump_subexp (exp, stream, elt + 3 + BYTES_TO_EXP_ELEM (len + 1));
 953       }
 954       break;
 955     case OP_SCOPE:
 956       {
 957         char *elem_name;
 958         int len;
 959
 960         fprintf_filtered (stream, "Type @");
 961         gdb_print_host_address (exp->elts[elt].type, stream);
 962         fprintf_filtered (stream, " (");
 963         type_print (exp->elts[elt].type, NULL, stream, 0);
 964         fprintf_filtered (stream, ") ");
 965
 966         len = longest_to_int (exp->elts[elt + 1].longconst);
 967         elem_name = &exp->elts[elt + 2].string;
 968
 969         fprintf_filtered (stream, "Field name: `%.*s'", len, elem_name);
 970         elt += 4 + BYTES_TO_EXP_ELEM (len + 1);
 971       }
 972       break;
 973     case TYPE_INSTANCE:
 974       {
 975         LONGEST len;
 976
 977         len = exp->elts[elt++].longconst;
 978         fprintf_filtered (stream, "%s TypeInstance: ", plongest (len));
 979         while (len-- > 0)
 980           {
 981             fprintf_filtered (stream, "Type @");
 982             gdb_print_host_address (exp->elts[elt].type, stream);
 983             fprintf_filtered (stream, " (");
 984             type_print (exp->elts[elt].type, NULL, stream, 0);
 985             fprintf_filtered (stream, ")");
 986             elt++;
 987             if (len > 0)
 988               fputs_filtered (", ", stream);
 989           }
 990         /* Ending LEN and ending TYPE_INSTANCE.  */
 991         elt += 2;
 992         elt = dump_subexp (exp, stream, elt);
 993       }
 994       break;
 995     default:
 996     case OP_NULL:
 997     case MULTI_SUBSCRIPT:
 998     case OP_F77_UNDETERMINED_ARGLIST:
 999     case OP_COMPLEX:
1000     case OP_STRING:
1001     case OP_BITSTRING:
1002     case OP_BOOL:
1003     case OP_M2_STRING:
1004     case OP_THIS:
1005     case OP_LABELED:
1006     case OP_NAME:
1007       fprintf_filtered (stream, "Unknown format");
1008     }
1009
1010   return elt;
1011 }
1012
1013 void
1014 dump_prefix_expression (struct expression *exp, struct ui_file *stream)
1015 {
1016   int elt;
1017
1018   fprintf_filtered (stream, "Dump of expression @ ");
1019   gdb_print_host_address (exp, stream);
1020   fputs_filtered (", after conversion to prefix form:\nExpression: `", stream);
1021   if (exp->elts[0].opcode != OP_TYPE)
1022     print_expression (exp, stream);
1023   else
1024     fputs_filtered ("Type printing not yet supported....", stream);
1025   fprintf_filtered (stream, "'\n\tLanguage %s, %d elements, %ld bytes each.\n",
1026                     exp->language_defn->la_name, exp->nelts,
1027                     (long) sizeof (union exp_element));
1028   fputs_filtered ("\n", stream);
1029
1030   for (elt = 0; elt < exp->nelts;)
1031     elt = dump_subexp (exp, stream, elt);
1032   fputs_filtered ("\n", stream);
1033 }