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         struct block *b;
 140
 141         (*pos) += 2;
 142         fprintf_filtered (stream, "%s@entry",
 143                           SYMBOL_PRINT_NAME (exp->elts[pc + 1].symbol));
 144       }
 145       return;
 146
 147     case OP_LAST:
 148       (*pos) += 2;
 149       fprintf_filtered (stream, "$%d",
 150                         longest_to_int (exp->elts[pc + 1].longconst));
 151       return;
 152
 153     case OP_REGISTER:
 154       {
 155         const char *name = &exp->elts[pc + 2].string;
 156
 157         (*pos) += 3 + BYTES_TO_EXP_ELEM (exp->elts[pc + 1].longconst + 1);
 158         fprintf_filtered (stream, "$%s", name);
 159         return;
 160       }
 161
 162     case OP_BOOL:
 163       (*pos) += 2;
 164       fprintf_filtered (stream, "%s",
 165                         longest_to_int (exp->elts[pc + 1].longconst)
 166                         ? "TRUE" : "FALSE");
 167       return;
 168
 169     case OP_INTERNALVAR:
 170       (*pos) += 2;
 171       fprintf_filtered (stream, "$%s",
 172                         internalvar_name (exp->elts[pc + 1].internalvar));
 173       return;
 174
 175     case OP_FUNCALL:
 176       (*pos) += 2;
 177       nargs = longest_to_int (exp->elts[pc + 1].longconst);
 178       print_subexp (exp, pos, stream, PREC_SUFFIX);
 179       fputs_filtered (" (", stream);
 180       for (tem = 0; tem < nargs; tem++)
 181         {
 182           if (tem != 0)
 183             fputs_filtered (", ", stream);
 184           print_subexp (exp, pos, stream, PREC_ABOVE_COMMA);
 185         }
 186       fputs_filtered (")", stream);
 187       return;
 188
 189     case OP_NAME:
 190       nargs = longest_to_int (exp->elts[pc + 1].longconst);
 191       (*pos) += 3 + BYTES_TO_EXP_ELEM (nargs + 1);
 192       fputs_filtered (&exp->elts[pc + 2].string, stream);
 193       return;
 194
 195     case OP_STRING:
 196       {
 197         struct value_print_options opts;
 198
 199         nargs = longest_to_int (exp->elts[pc + 1].longconst);
 200         (*pos) += 3 + BYTES_TO_EXP_ELEM (nargs + 1);
 201         /* LA_PRINT_STRING will print using the current repeat count threshold.
 202            If necessary, we can temporarily set it to zero, or pass it as an
 203            additional parameter to LA_PRINT_STRING.  -fnf */
 204         get_user_print_options (&opts);
 205         LA_PRINT_STRING (stream, builtin_type (exp->gdbarch)->builtin_char,
 206                          &exp->elts[pc + 2].string, nargs, NULL, 0, &opts);
 207       }
 208       return;
 209
 210     case OP_BITSTRING:
 211       nargs = longest_to_int (exp->elts[pc + 1].longconst);
 212       (*pos)
 213         += 3 + BYTES_TO_EXP_ELEM ((nargs + HOST_CHAR_BIT - 1) / HOST_CHAR_BIT);
 214       fprintf_unfiltered (stream, "B'<unimplemented>'");
 215       return;
 216
 217     case OP_OBJC_NSSTRING:      /* Objective-C Foundation Class
 218                                    NSString constant.  */
 219       {
 220         struct value_print_options opts;
 221
 222         nargs = longest_to_int (exp->elts[pc + 1].longconst);
 223         (*pos) += 3 + BYTES_TO_EXP_ELEM (nargs + 1);
 224         fputs_filtered ("@\"", stream);
 225         get_user_print_options (&opts);
 226         LA_PRINT_STRING (stream, builtin_type (exp->gdbarch)->builtin_char,
 227                          &exp->elts[pc + 2].string, nargs, NULL, 0, &opts);
 228         fputs_filtered ("\"", stream);
 229       }
 230       return;
 231
 232     case OP_OBJC_MSGCALL:
 233       {                 /* Objective C message (method) call.  */
 234         char *selector;
 235
 236         (*pos) += 3;
 237         nargs = longest_to_int (exp->elts[pc + 2].longconst);
 238         fprintf_unfiltered (stream, "[");
 239         print_subexp (exp, pos, stream, PREC_SUFFIX);
 240         if (0 == target_read_string (exp->elts[pc + 1].longconst,
 241                                      &selector, 1024, NULL))
 242           {
 243             error (_("bad selector"));
 244             return;
 245           }
 246         if (nargs)
 247           {
 248             char *s, *nextS;
 249
 250             s = alloca (strlen (selector) + 1);
 251             strcpy (s, selector);
 252             for (tem = 0; tem < nargs; tem++)
 253               {
 254                 nextS = strchr (s, ':');
 255                 gdb_assert (nextS);     /* Make sure we found ':'.  */
 256                 *nextS = '\0';
 257                 fprintf_unfiltered (stream, " %s: ", s);
 258                 s = nextS + 1;
 259                 print_subexp (exp, pos, stream, PREC_ABOVE_COMMA);
 260               }
 261           }
 262         else
 263           {
 264             fprintf_unfiltered (stream, " %s", selector);
 265           }
 266         fprintf_unfiltered (stream, "]");
 267         /* "selector" was malloc'd by target_read_string.  Free it.  */
 268         xfree (selector);
 269         return;
 270       }
 271
 272     case OP_ARRAY:
 273       (*pos) += 3;
 274       nargs = longest_to_int (exp->elts[pc + 2].longconst);
 275       nargs -= longest_to_int (exp->elts[pc + 1].longconst);
 276       nargs++;
 277       tem = 0;
 278       if (exp->elts[pc + 4].opcode == OP_LONG
 279           && exp->elts[pc + 5].type
 280              == builtin_type (exp->gdbarch)->builtin_char
 281           && exp->language_defn->la_language == language_c)
 282         {
 283           /* Attempt to print C character arrays using string syntax.
 284              Walk through the args, picking up one character from each
 285              of the OP_LONG expression elements.  If any array element
 286              does not match our expection of what we should find for
 287              a simple string, revert back to array printing.  Note that
 288              the last expression element is an explicit null terminator
 289              byte, which doesn't get printed.  */
 290           tempstr = alloca (nargs);
 291           pc += 4;
 292           while (tem < nargs)
 293             {
 294               if (exp->elts[pc].opcode != OP_LONG
 295                   || exp->elts[pc + 1].type
 296                      != builtin_type (exp->gdbarch)->builtin_char)
 297                 {
 298                   /* Not a simple array of char, use regular array
 299                      printing.  */
 300                   tem = 0;
 301                   break;
 302                 }
 303               else
 304                 {
 305                   tempstr[tem++] =
 306                     longest_to_int (exp->elts[pc + 2].longconst);
 307                   pc += 4;
 308                 }
 309             }
 310         }
 311       if (tem > 0)
 312         {
 313           struct value_print_options opts;
 314
 315           get_user_print_options (&opts);
 316           LA_PRINT_STRING (stream, builtin_type (exp->gdbarch)->builtin_char,
 317                            tempstr, nargs - 1, NULL, 0, &opts);
 318           (*pos) = pc;
 319         }
 320       else
 321         {
 322           fputs_filtered (" {", stream);
 323           for (tem = 0; tem < nargs; tem++)
 324             {
 325               if (tem != 0)
 326                 {
 327                   fputs_filtered (", ", stream);
 328                 }
 329               print_subexp (exp, pos, stream, PREC_ABOVE_COMMA);
 330             }
 331           fputs_filtered ("}", stream);
 332         }
 333       return;
 334
 335     case OP_LABELED:
 336       tem = longest_to_int (exp->elts[pc + 1].longconst);
 337       (*pos) += 3 + BYTES_TO_EXP_ELEM (tem + 1);
 338       /* Gcc support both these syntaxes.  Unsure which is preferred.  */
 339 #if 1
 340       fputs_filtered (&exp->elts[pc + 2].string, stream);
 341       fputs_filtered (": ", stream);
 342 #else
 343       fputs_filtered (".", stream);
 344       fputs_filtered (&exp->elts[pc + 2].string, stream);
 345       fputs_filtered ("=", stream);
 346 #endif
 347       print_subexp (exp, pos, stream, PREC_SUFFIX);
 348       return;
 349
 350     case TERNOP_COND:
 351       if ((int) prec > (int) PREC_COMMA)
 352         fputs_filtered ("(", stream);
 353       /* Print the subexpressions, forcing parentheses
 354          around any binary operations within them.
 355          This is more parentheses than are strictly necessary,
 356          but it looks clearer.  */
 357       print_subexp (exp, pos, stream, PREC_HYPER);
 358       fputs_filtered (" ? ", stream);
 359       print_subexp (exp, pos, stream, PREC_HYPER);
 360       fputs_filtered (" : ", stream);
 361       print_subexp (exp, pos, stream, PREC_HYPER);
 362       if ((int) prec > (int) PREC_COMMA)
 363         fputs_filtered (")", stream);
 364       return;
 365
 366     case TERNOP_SLICE:
 367     case TERNOP_SLICE_COUNT:
 368       print_subexp (exp, pos, stream, PREC_SUFFIX);
 369       fputs_filtered ("(", stream);
 370       print_subexp (exp, pos, stream, PREC_ABOVE_COMMA);
 371       fputs_filtered (opcode == TERNOP_SLICE ? " : " : " UP ", stream);
 372       print_subexp (exp, pos, stream, PREC_ABOVE_COMMA);
 373       fputs_filtered (")", stream);
 374       return;
 375
 376     case STRUCTOP_STRUCT:
 377       tem = longest_to_int (exp->elts[pc + 1].longconst);
 378       (*pos) += 3 + BYTES_TO_EXP_ELEM (tem + 1);
 379       print_subexp (exp, pos, stream, PREC_SUFFIX);
 380       fputs_filtered (".", stream);
 381       fputs_filtered (&exp->elts[pc + 2].string, stream);
 382       return;
 383
 384       /* Will not occur for Modula-2.  */
 385     case STRUCTOP_PTR:
 386       tem = longest_to_int (exp->elts[pc + 1].longconst);
 387       (*pos) += 3 + BYTES_TO_EXP_ELEM (tem + 1);
 388       print_subexp (exp, pos, stream, PREC_SUFFIX);
 389       fputs_filtered ("->", stream);
 390       fputs_filtered (&exp->elts[pc + 2].string, stream);
 391       return;
 392
 393     case STRUCTOP_MEMBER:
 394       print_subexp (exp, pos, stream, PREC_SUFFIX);
 395       fputs_filtered (".*", stream);
 396       print_subexp (exp, pos, stream, PREC_SUFFIX);
 397       return;
 398
 399     case STRUCTOP_MPTR:
 400       print_subexp (exp, pos, stream, PREC_SUFFIX);
 401       fputs_filtered ("->*", stream);
 402       print_subexp (exp, pos, stream, PREC_SUFFIX);
 403       return;
 404
 405     case BINOP_SUBSCRIPT:
 406       print_subexp (exp, pos, stream, PREC_SUFFIX);
 407       fputs_filtered ("[", stream);
 408       print_subexp (exp, pos, stream, PREC_ABOVE_COMMA);
 409       fputs_filtered ("]", stream);
 410       return;
 411
 412     case UNOP_POSTINCREMENT:
 413       print_subexp (exp, pos, stream, PREC_SUFFIX);
 414       fputs_filtered ("++", stream);
 415       return;
 416
 417     case UNOP_POSTDECREMENT:
 418       print_subexp (exp, pos, stream, PREC_SUFFIX);
 419       fputs_filtered ("--", stream);
 420       return;
 421
 422     case UNOP_CAST:
 423       (*pos) += 2;
 424       if ((int) prec > (int) PREC_PREFIX)
 425         fputs_filtered ("(", stream);
 426       fputs_filtered ("(", stream);
 427       type_print (exp->elts[pc + 1].type, "", stream, 0);
 428       fputs_filtered (") ", stream);
 429       print_subexp (exp, pos, stream, PREC_PREFIX);
 430       if ((int) prec > (int) PREC_PREFIX)
 431         fputs_filtered (")", stream);
 432       return;
 433
 434     case UNOP_DYNAMIC_CAST:
 435     case UNOP_REINTERPRET_CAST:
 436       fputs_filtered (opcode == UNOP_DYNAMIC_CAST ? "dynamic_cast"
 437                       : "reinterpret_cast", stream);
 438       fputs_filtered ("<", stream);
 439       (*pos) += 2;
 440       type_print (exp->elts[pc + 1].type, "", stream, 0);
 441       fputs_filtered ("> (", stream);
 442       print_subexp (exp, pos, stream, PREC_PREFIX);
 443       fputs_filtered (")", stream);
 444       return;
 445
 446     case UNOP_MEMVAL:
 447       (*pos) += 2;
 448       if ((int) prec > (int) PREC_PREFIX)
 449         fputs_filtered ("(", stream);
 450       if (TYPE_CODE (exp->elts[pc + 1].type) == TYPE_CODE_FUNC
 451           && exp->elts[pc + 3].opcode == OP_LONG)
 452         {
 453           struct value_print_options opts;
 454
 455           /* We have a minimal symbol fn, probably.  It's encoded
 456              as a UNOP_MEMVAL (function-type) of an OP_LONG (int, address).
 457              Swallow the OP_LONG (including both its opcodes); ignore
 458              its type; print the value in the type of the MEMVAL.  */
 459           (*pos) += 4;
 460           val = value_at_lazy (exp->elts[pc + 1].type,
 461                                (CORE_ADDR) exp->elts[pc + 5].longconst);
 462           get_raw_print_options (&opts);
 463           value_print (val, stream, &opts);
 464         }
 465       else
 466         {
 467           fputs_filtered ("{", stream);
 468           type_print (exp->elts[pc + 1].type, "", stream, 0);
 469           fputs_filtered ("} ", stream);
 470           print_subexp (exp, pos, stream, PREC_PREFIX);
 471         }
 472       if ((int) prec > (int) PREC_PREFIX)
 473         fputs_filtered (")", stream);
 474       return;
 475
 476     case UNOP_MEMVAL_TLS:
 477       (*pos) += 3;
 478       if ((int) prec > (int) PREC_PREFIX)
 479         fputs_filtered ("(", stream);
 480       fputs_filtered ("{", stream);
 481       type_print (exp->elts[pc + 2].type, "", stream, 0);
 482       fputs_filtered ("} ", stream);
 483       print_subexp (exp, pos, stream, PREC_PREFIX);
 484       if ((int) prec > (int) PREC_PREFIX)
 485         fputs_filtered (")", stream);
 486       return;
 487
 488     case BINOP_ASSIGN_MODIFY:
 489       opcode = exp->elts[pc + 1].opcode;
 490       (*pos) += 2;
 491       myprec = PREC_ASSIGN;
 492       assoc = 1;
 493       assign_modify = 1;
 494       op_str = "???";
 495       for (tem = 0; op_print_tab[tem].opcode != OP_NULL; tem++)
 496         if (op_print_tab[tem].opcode == opcode)
 497           {
 498             op_str = op_print_tab[tem].string;
 499             break;
 500           }
 501       if (op_print_tab[tem].opcode != opcode)
 502         /* Not found; don't try to keep going because we don't know how
 503            to interpret further elements.  */
 504         error (_("Invalid expression"));
 505       break;
 506
 507       /* C++ ops */
 508
 509     case OP_THIS:
 510       ++(*pos);
 511       if (exp->language_defn->la_name_of_this)
 512         fputs_filtered (exp->language_defn->la_name_of_this, stream);
 513       else
 514         fprintf_filtered (stream, _("<language %s has no 'this'>"),
 515                           exp->language_defn->la_name);
 516       return;
 517
 518       /* Modula-2 ops */
 519
 520     case MULTI_SUBSCRIPT:
 521       (*pos) += 2;
 522       nargs = longest_to_int (exp->elts[pc + 1].longconst);
 523       print_subexp (exp, pos, stream, PREC_SUFFIX);
 524       fprintf_unfiltered (stream, " [");
 525       for (tem = 0; tem < nargs; tem++)
 526         {
 527           if (tem != 0)
 528             fprintf_unfiltered (stream, ", ");
 529           print_subexp (exp, pos, stream, PREC_ABOVE_COMMA);
 530         }
 531       fprintf_unfiltered (stream, "]");
 532       return;
 533
 534     case BINOP_VAL:
 535       (*pos) += 2;
 536       fprintf_unfiltered (stream, "VAL(");
 537       type_print (exp->elts[pc + 1].type, "", stream, 0);
 538       fprintf_unfiltered (stream, ",");
 539       print_subexp (exp, pos, stream, PREC_PREFIX);
 540       fprintf_unfiltered (stream, ")");
 541       return;
 542
 543     case TYPE_INSTANCE:
 544       {
 545         LONGEST count = exp->elts[pc + 1].longconst;
 546
 547         /* The COUNT.  */
 548         (*pos)++;
 549         fputs_unfiltered ("TypesInstance(", stream);
 550         while (count-- > 0)
 551           {
 552             type_print (exp->elts[(*pos)++].type, "", stream, 0);
 553             if (count > 0)
 554               fputs_unfiltered (",", stream);
 555           }
 556         fputs_unfiltered (",", stream);
 557         /* Ending COUNT and ending TYPE_INSTANCE.  */
 558         (*pos) += 2;
 559         print_subexp (exp, pos, stream, PREC_PREFIX);
 560         fputs_unfiltered (")", stream);
 561         return;
 562       }
 563
 564       /* Default ops */
 565
 566     default:
 567       op_str = "???";
 568       for (tem = 0; op_print_tab[tem].opcode != OP_NULL; tem++)
 569         if (op_print_tab[tem].opcode == opcode)
 570           {
 571             op_str = op_print_tab[tem].string;
 572             myprec = op_print_tab[tem].precedence;
 573             assoc = op_print_tab[tem].right_assoc;
 574             break;
 575           }
 576       if (op_print_tab[tem].opcode != opcode)
 577         /* Not found; don't try to keep going because we don't know how
 578            to interpret further elements.  For example, this happens
 579            if opcode is OP_TYPE.  */
 580         error (_("Invalid expression"));
 581     }
 582
 583   /* Note that PREC_BUILTIN will always emit parentheses.  */
 584   if ((int) myprec < (int) prec)
 585     fputs_filtered ("(", stream);
 586   if ((int) opcode > (int) BINOP_END)
 587     {
 588       if (assoc)
 589         {
 590           /* Unary postfix operator.  */
 591           print_subexp (exp, pos, stream, PREC_SUFFIX);
 592           fputs_filtered (op_str, stream);
 593         }
 594       else
 595         {
 596           /* Unary prefix operator.  */
 597           fputs_filtered (op_str, stream);
 598           if (myprec == PREC_BUILTIN_FUNCTION)
 599             fputs_filtered ("(", stream);
 600           print_subexp (exp, pos, stream, PREC_PREFIX);
 601           if (myprec == PREC_BUILTIN_FUNCTION)
 602             fputs_filtered (")", stream);
 603         }
 604     }
 605   else
 606     {
 607       /* Binary operator.  */
 608       /* Print left operand.
 609          If operator is right-associative,
 610          increment precedence for this operand.  */
 611       print_subexp (exp, pos, stream,
 612                     (enum precedence) ((int) myprec + assoc));
 613       /* Print the operator itself.  */
 614       if (assign_modify)
 615         fprintf_filtered (stream, " %s= ", op_str);
 616       else if (op_str[0] == ',')
 617         fprintf_filtered (stream, "%s ", op_str);
 618       else
 619         fprintf_filtered (stream, " %s ", op_str);
 620       /* Print right operand.
 621          If operator is left-associative,
 622          increment precedence for this operand.  */
 623       print_subexp (exp, pos, stream,
 624                     (enum precedence) ((int) myprec + !assoc));
 625     }
 626
 627   if ((int) myprec < (int) prec)
 628     fputs_filtered (")", stream);
 629 }
 630
 631 /* Return the operator corresponding to opcode OP as
 632    a string.   NULL indicates that the opcode was not found in the
 633    current language table.  */
 634 char *
 635 op_string (enum exp_opcode op)
 636 {
 637   int tem;
 638   const struct op_print *op_print_tab;
 639
 640   op_print_tab = current_language->la_op_print_tab;
 641   for (tem = 0; op_print_tab[tem].opcode != OP_NULL; tem++)
 642     if (op_print_tab[tem].opcode == op)
 643       return op_print_tab[tem].string;
 644   return NULL;
 645 }
 646
 647 /* Support for dumping the raw data from expressions in a human readable
 648    form.  */
 649
 650 static char *op_name (struct expression *, enum exp_opcode);
 651 static int dump_subexp_body (struct expression *exp, struct ui_file *, int);
 652
 653 /* Name for OPCODE, when it appears in expression EXP.  */
 654
 655 static char *
 656 op_name (struct expression *exp, enum exp_opcode opcode)
 657 {
 658   return exp->language_defn->la_exp_desc->op_name (opcode);
 659 }
 660
 661 /* Default name for the standard operator OPCODE (i.e., one defined in
 662    the definition of enum exp_opcode).  */
 663
 664 char *
 665 op_name_standard (enum exp_opcode opcode)
 666 {
 667   switch (opcode)
 668     {
 669     default:
 670       {
 671         static char buf[30];
 672
 673         sprintf (buf, "<unknown %d>", opcode);
 674         return buf;
 675       }
 676 #define OP(name)        \
 677     case name:          \
 678       return #name ;
 679 #include "std-operator.def"
 680 #undef OP
 681     }
 682 }
 683
 684 /* Print a raw dump of expression EXP to STREAM.
 685    NOTE, if non-NULL, is printed as extra explanatory text.  */
 686
 687 void
 688 dump_raw_expression (struct expression *exp, struct ui_file *stream,
 689                      char *note)
 690 {
 691   int elt;
 692   char *opcode_name;
 693   char *eltscan;
 694   int eltsize;
 695
 696   fprintf_filtered (stream, "Dump of expression @ ");
 697   gdb_print_host_address (exp, stream);
 698   if (note)
 699     fprintf_filtered (stream, ", %s:", note);
 700   fprintf_filtered (stream, "\n\tLanguage %s, %d elements, %ld bytes each.\n",
 701                     exp->language_defn->la_name, exp->nelts,
 702                     (long) sizeof (union exp_element));
 703   fprintf_filtered (stream, "\t%5s  %20s  %16s  %s\n", "Index", "Opcode",
 704                     "Hex Value", "String Value");
 705   for (elt = 0; elt < exp->nelts; elt++)
 706     {
 707       fprintf_filtered (stream, "\t%5d  ", elt);
 708       opcode_name = op_name (exp, exp->elts[elt].opcode);
 709
 710       fprintf_filtered (stream, "%20s  ", opcode_name);
 711       print_longest (stream, 'd', 0, exp->elts[elt].longconst);
 712       fprintf_filtered (stream, "  ");
 713
 714       for (eltscan = (char *) &exp->elts[elt],
 715            eltsize = sizeof (union exp_element);
 716            eltsize-- > 0;
 717            eltscan++)
 718         {
 719           fprintf_filtered (stream, "%c",
 720                             isprint (*eltscan) ? (*eltscan & 0xFF) : '.');
 721         }
 722       fprintf_filtered (stream, "\n");
 723     }
 724 }
 725
 726 /* Dump the subexpression of prefix expression EXP whose operator is at
 727    position ELT onto STREAM.  Returns the position of the next
 728    subexpression in EXP.  */
 729
 730 int
 731 dump_subexp (struct expression *exp, struct ui_file *stream, int elt)
 732 {
 733   static int indent = 0;
 734   int i;
 735
 736   fprintf_filtered (stream, "\n");
 737   fprintf_filtered (stream, "\t%5d  ", elt);
 738
 739   for (i = 1; i <= indent; i++)
 740     fprintf_filtered (stream, " ");
 741   indent += 2;
 742
 743   fprintf_filtered (stream, "%-20s  ", op_name (exp, exp->elts[elt].opcode));
 744
 745   elt = dump_subexp_body (exp, stream, elt);
 746
 747   indent -= 2;
 748
 749   return elt;
 750 }
 751
 752 /* Dump the operands of prefix expression EXP whose opcode is at
 753    position ELT onto STREAM.  Returns the position of the next
 754    subexpression in EXP.  */
 755
 756 static int
 757 dump_subexp_body (struct expression *exp, struct ui_file *stream, int elt)
 758 {
 759   return exp->language_defn->la_exp_desc->dump_subexp_body (exp, stream, elt);
 760 }
 761
 762 /* Default value for subexp_body in exp_descriptor vector.  */
 763
 764 int
 765 dump_subexp_body_standard (struct expression *exp,
 766                            struct ui_file *stream, int elt)
 767 {
 768   int opcode = exp->elts[elt++].opcode;
 769
 770   switch (opcode)
 771     {
 772     case TERNOP_COND:
 773     case TERNOP_SLICE:
 774     case TERNOP_SLICE_COUNT:
 775       elt = dump_subexp (exp, stream, elt);
 776       /* FALL THROUGH */
 777     case BINOP_ADD:
 778     case BINOP_SUB:
 779     case BINOP_MUL:
 780     case BINOP_DIV:
 781     case BINOP_REM:
 782     case BINOP_MOD:
 783     case BINOP_LSH:
 784     case BINOP_RSH:
 785     case BINOP_LOGICAL_AND:
 786     case BINOP_LOGICAL_OR:
 787     case BINOP_BITWISE_AND:
 788     case BINOP_BITWISE_IOR:
 789     case BINOP_BITWISE_XOR:
 790     case BINOP_EQUAL:
 791     case BINOP_NOTEQUAL:
 792     case BINOP_LESS:
 793     case BINOP_GTR:
 794     case BINOP_LEQ:
 795     case BINOP_GEQ:
 796     case BINOP_REPEAT:
 797     case BINOP_ASSIGN:
 798     case BINOP_COMMA:
 799     case BINOP_SUBSCRIPT:
 800     case BINOP_EXP:
 801     case BINOP_MIN:
 802     case BINOP_MAX:
 803     case BINOP_INTDIV:
 804     case BINOP_ASSIGN_MODIFY:
 805     case BINOP_VAL:
 806     case BINOP_CONCAT:
 807     case BINOP_IN:
 808     case BINOP_RANGE:
 809     case BINOP_END:
 810     case STRUCTOP_MEMBER:
 811     case STRUCTOP_MPTR:
 812       elt = dump_subexp (exp, stream, elt);
 813       /* FALL THROUGH */
 814     case UNOP_NEG:
 815     case UNOP_LOGICAL_NOT:
 816     case UNOP_COMPLEMENT:
 817     case UNOP_IND:
 818     case UNOP_ADDR:
 819     case UNOP_PREINCREMENT:
 820     case UNOP_POSTINCREMENT:
 821     case UNOP_PREDECREMENT:
 822     case UNOP_POSTDECREMENT:
 823     case UNOP_SIZEOF:
 824     case UNOP_PLUS:
 825     case UNOP_CAP:
 826     case UNOP_CHR:
 827     case UNOP_ORD:
 828     case UNOP_ABS:
 829     case UNOP_FLOAT:
 830     case UNOP_HIGH:
 831     case UNOP_MAX:
 832     case UNOP_MIN:
 833     case UNOP_ODD:
 834     case UNOP_TRUNC:
 835       elt = dump_subexp (exp, stream, elt);
 836       break;
 837     case OP_LONG:
 838       fprintf_filtered (stream, "Type @");
 839       gdb_print_host_address (exp->elts[elt].type, stream);
 840       fprintf_filtered (stream, " (");
 841       type_print (exp->elts[elt].type, NULL, stream, 0);
 842       fprintf_filtered (stream, "), value %ld (0x%lx)",
 843                         (long) exp->elts[elt + 1].longconst,
 844                         (long) exp->elts[elt + 1].longconst);
 845       elt += 3;
 846       break;
 847     case OP_DOUBLE:
 848       fprintf_filtered (stream, "Type @");
 849       gdb_print_host_address (exp->elts[elt].type, stream);
 850       fprintf_filtered (stream, " (");
 851       type_print (exp->elts[elt].type, NULL, stream, 0);
 852       fprintf_filtered (stream, "), value %g",
 853                         (double) exp->elts[elt + 1].doubleconst);
 854       elt += 3;
 855       break;
 856     case OP_VAR_VALUE:
 857       fprintf_filtered (stream, "Block @");
 858       gdb_print_host_address (exp->elts[elt].block, stream);
 859       fprintf_filtered (stream, ", symbol @");
 860       gdb_print_host_address (exp->elts[elt + 1].symbol, stream);
 861       fprintf_filtered (stream, " (%s)",
 862                         SYMBOL_PRINT_NAME (exp->elts[elt + 1].symbol));
 863       elt += 3;
 864       break;
 865     case OP_VAR_ENTRY_VALUE:
 866       fprintf_filtered (stream, "Entry value of symbol @");
 867       gdb_print_host_address (exp->elts[elt].symbol, stream);
 868       fprintf_filtered (stream, " (%s)",
 869                         SYMBOL_PRINT_NAME (exp->elts[elt].symbol));
 870       elt += 2;
 871       break;
 872     case OP_LAST:
 873       fprintf_filtered (stream, "History element %ld",
 874                         (long) exp->elts[elt].longconst);
 875       elt += 2;
 876       break;
 877     case OP_REGISTER:
 878       fprintf_filtered (stream, "Register $%s", &exp->elts[elt + 1].string);
 879       elt += 3 + BYTES_TO_EXP_ELEM (exp->elts[elt].longconst + 1);
 880       break;
 881     case OP_INTERNALVAR:
 882       fprintf_filtered (stream, "Internal var @");
 883       gdb_print_host_address (exp->elts[elt].internalvar, stream);
 884       fprintf_filtered (stream, " (%s)",
 885                         internalvar_name (exp->elts[elt].internalvar));
 886       elt += 2;
 887       break;
 888     case OP_FUNCALL:
 889       {
 890         int i, nargs;
 891
 892         nargs = longest_to_int (exp->elts[elt].longconst);
 893
 894         fprintf_filtered (stream, "Number of args: %d", nargs);
 895         elt += 2;
 896
 897         for (i = 1; i <= nargs + 1; i++)
 898           elt = dump_subexp (exp, stream, elt);
 899       }
 900       break;
 901     case OP_ARRAY:
 902       {
 903         int lower, upper;
 904         int i;
 905
 906         lower = longest_to_int (exp->elts[elt].longconst);
 907         upper = longest_to_int (exp->elts[elt + 1].longconst);
 908
 909         fprintf_filtered (stream, "Bounds [%d:%d]", lower, upper);
 910         elt += 3;
 911
 912         for (i = 1; i <= upper - lower + 1; i++)
 913           elt = dump_subexp (exp, stream, elt);
 914       }
 915       break;
 916     case UNOP_MEMVAL:
 917     case UNOP_CAST:
 918     case UNOP_DYNAMIC_CAST:
 919     case UNOP_REINTERPRET_CAST:
 920       fprintf_filtered (stream, "Type @");
 921       gdb_print_host_address (exp->elts[elt].type, stream);
 922       fprintf_filtered (stream, " (");
 923       type_print (exp->elts[elt].type, NULL, stream, 0);
 924       fprintf_filtered (stream, ")");
 925       elt = dump_subexp (exp, stream, elt + 2);
 926       break;
 927     case UNOP_MEMVAL_TLS:
 928       fprintf_filtered (stream, "TLS type @");
 929       gdb_print_host_address (exp->elts[elt + 1].type, stream);
 930       fprintf_filtered (stream, " (__thread /* \"%s\" */ ",
 931                         (exp->elts[elt].objfile == NULL ? "(null)"
 932                          : exp->elts[elt].objfile->name));
 933       type_print (exp->elts[elt + 1].type, NULL, stream, 0);
 934       fprintf_filtered (stream, ")");
 935       elt = dump_subexp (exp, stream, elt + 3);
 936       break;
 937     case OP_TYPE:
 938       fprintf_filtered (stream, "Type @");
 939       gdb_print_host_address (exp->elts[elt].type, stream);
 940       fprintf_filtered (stream, " (");
 941       type_print (exp->elts[elt].type, NULL, stream, 0);
 942       fprintf_filtered (stream, ")");
 943       elt += 2;
 944       break;
 945     case STRUCTOP_STRUCT:
 946     case STRUCTOP_PTR:
 947       {
 948         char *elem_name;
 949         int len;
 950
 951         len = longest_to_int (exp->elts[elt].longconst);
 952         elem_name = &exp->elts[elt + 1].string;
 953
 954         fprintf_filtered (stream, "Element name: `%.*s'", len, elem_name);
 955         elt = dump_subexp (exp, stream, elt + 3 + BYTES_TO_EXP_ELEM (len + 1));
 956       }
 957       break;
 958     case OP_SCOPE:
 959       {
 960         char *elem_name;
 961         int len;
 962
 963         fprintf_filtered (stream, "Type @");
 964         gdb_print_host_address (exp->elts[elt].type, stream);
 965         fprintf_filtered (stream, " (");
 966         type_print (exp->elts[elt].type, NULL, stream, 0);
 967         fprintf_filtered (stream, ") ");
 968
 969         len = longest_to_int (exp->elts[elt + 1].longconst);
 970         elem_name = &exp->elts[elt + 2].string;
 971
 972         fprintf_filtered (stream, "Field name: `%.*s'", len, elem_name);
 973         elt += 4 + BYTES_TO_EXP_ELEM (len + 1);
 974       }
 975       break;
 976     case TYPE_INSTANCE:
 977       {
 978         char *elem_name;
 979         LONGEST len;
 980
 981         len = exp->elts[elt++].longconst;
 982         fprintf_filtered (stream, "%s TypeInstance: ", plongest (len));
 983         while (len-- > 0)
 984           {
 985             fprintf_filtered (stream, "Type @");
 986             gdb_print_host_address (exp->elts[elt].type, stream);
 987             fprintf_filtered (stream, " (");
 988             type_print (exp->elts[elt].type, NULL, stream, 0);
 989             fprintf_filtered (stream, ")");
 990             elt++;
 991             if (len > 0)
 992               fputs_filtered (", ", stream);
 993           }
 994         /* Ending LEN and ending TYPE_INSTANCE.  */
 995         elt += 2;
 996         elt = dump_subexp (exp, stream, elt);
 997       }
 998       break;
 999     default:
1000     case OP_NULL:
1001     case MULTI_SUBSCRIPT:
1002     case OP_F77_UNDETERMINED_ARGLIST:
1003     case OP_COMPLEX:
1004     case OP_STRING:
1005     case OP_BITSTRING:
1006     case OP_BOOL:
1007     case OP_M2_STRING:
1008     case OP_THIS:
1009     case OP_LABELED:
1010     case OP_NAME:
1011       fprintf_filtered (stream, "Unknown format");
1012     }
1013
1014   return elt;
1015 }
1016
1017 void
1018 dump_prefix_expression (struct expression *exp, struct ui_file *stream)
1019 {
1020   int elt;
1021
1022   fprintf_filtered (stream, "Dump of expression @ ");
1023   gdb_print_host_address (exp, stream);
1024   fputs_filtered (", after conversion to prefix form:\nExpression: `", stream);
1025   if (exp->elts[0].opcode != OP_TYPE)
1026     print_expression (exp, stream);
1027   else
1028     fputs_filtered ("Type printing not yet supported....", stream);
1029   fprintf_filtered (stream, "'\n\tLanguage %s, %d elements, %ld bytes each.\n",
1030                     exp->language_defn->la_name, exp->nelts,
1031                     (long) sizeof (union exp_element));
1032   fputs_filtered ("\n", stream);
1033
1034   for (elt = 0; elt < exp->nelts;)
1035     elt = dump_subexp (exp, stream, elt);
1036   fputs_filtered ("\n", stream);
1037 }