gdb/expprint.c

   1 /* Print in infix form a struct expression.
   2
   3    Copyright (C) 1986-2020 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 3 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, see <http://www.gnu.org/licenses/>.  */
  19
  20 #include "defs.h"
  21 #include "symtab.h"
  22 #include "gdbtypes.h"
  23 #include "expression.h"
  24 #include "value.h"
  25 #include "language.h"
  26 #include "parser-defs.h"
  27 #include "user-regs.h"          /* For user_reg_map_regnum_to_name.  */
  28 #include "target.h"
  29 #include "block.h"
  30 #include "objfiles.h"
  31 #include "valprint.h"
  32 #include "cli/cli-style.h"
  33
  34 #include <ctype.h>
  35
  36 void
  37 print_expression (struct expression *exp, struct ui_file *stream)
  38 {
  39   int pc = 0;
  40
  41   print_subexp (exp, &pc, stream, PREC_NULL);
  42 }
  43
  44 /* Print the subexpression of EXP that starts in position POS, on STREAM.
  45    PREC is the precedence of the surrounding operator;
  46    if the precedence of the main operator of this subexpression is less,
  47    parentheses are needed here.  */
  48
  49 void
  50 print_subexp (struct expression *exp, int *pos,
  51               struct ui_file *stream, enum precedence prec)
  52 {
  53   exp->language_defn->expression_ops ()->print_subexp (exp, pos, stream,
  54                                                        prec);
  55 }
  56
  57 /* Standard implementation of print_subexp for use in language_defn
  58    vectors.  */
  59 void
  60 print_subexp_standard (struct expression *exp, int *pos,
  61                        struct ui_file *stream, enum precedence prec)
  62 {
  63   unsigned tem;
  64   const struct op_print *op_print_tab;
  65   int pc;
  66   unsigned nargs;
  67   const char *op_str;
  68   int assign_modify = 0;
  69   enum exp_opcode opcode;
  70   enum precedence myprec = PREC_NULL;
  71   /* Set to 1 for a right-associative operator.  */
  72   int assoc = 0;
  73   struct value *val;
  74   char *tempstr = NULL;
  75
  76   op_print_tab = exp->language_defn->opcode_print_table ();
  77   pc = (*pos)++;
  78   opcode = exp->elts[pc].opcode;
  79   switch (opcode)
  80     {
  81       /* Common ops */
  82
  83     case OP_TYPE:
  84       (*pos) += 2;
  85       type_print (exp->elts[pc + 1].type, "", stream, 0);
  86       return;
  87
  88     case OP_SCOPE:
  89       myprec = PREC_PREFIX;
  90       assoc = 0;
  91       fputs_filtered (exp->elts[pc + 1].type->name (), stream);
  92       fputs_filtered ("::", stream);
  93       nargs = longest_to_int (exp->elts[pc + 2].longconst);
  94       (*pos) += 4 + BYTES_TO_EXP_ELEM (nargs + 1);
  95       fputs_filtered (&exp->elts[pc + 3].string, stream);
  96       return;
  97
  98     case OP_LONG:
  99       {
 100         struct value_print_options opts;
 101
 102         get_no_prettyformat_print_options (&opts);
 103         (*pos) += 3;
 104         value_print (value_from_longest (exp->elts[pc + 1].type,
 105                                          exp->elts[pc + 2].longconst),
 106                      stream, &opts);
 107       }
 108       return;
 109
 110     case OP_FLOAT:
 111       {
 112         struct value_print_options opts;
 113
 114         get_no_prettyformat_print_options (&opts);
 115         (*pos) += 3;
 116         value_print (value_from_contents (exp->elts[pc + 1].type,
 117                                           exp->elts[pc + 2].floatconst),
 118                      stream, &opts);
 119       }
 120       return;
 121
 122     case OP_VAR_VALUE:
 123       {
 124         const struct block *b;
 125
 126         (*pos) += 3;
 127         b = exp->elts[pc + 1].block;
 128         if (b != NULL
 129             && BLOCK_FUNCTION (b) != NULL
 130             && BLOCK_FUNCTION (b)->print_name () != NULL)
 131           {
 132             fputs_filtered (BLOCK_FUNCTION (b)->print_name (), stream);
 133             fputs_filtered ("::", stream);
 134           }
 135         fputs_filtered (exp->elts[pc + 2].symbol->print_name (), stream);
 136       }
 137       return;
 138
 139     case OP_VAR_MSYM_VALUE:
 140       {
 141         (*pos) += 3;
 142         fputs_filtered (exp->elts[pc + 2].msymbol->print_name (), stream);
 143       }
 144       return;
 145
 146     case OP_FUNC_STATIC_VAR:
 147       {
 148         tem = longest_to_int (exp->elts[pc + 1].longconst);
 149         (*pos) += 3 + BYTES_TO_EXP_ELEM (tem + 1);
 150         fputs_filtered (&exp->elts[pc + 1].string, stream);
 151       }
 152       return;
 153
 154     case OP_VAR_ENTRY_VALUE:
 155       {
 156         (*pos) += 2;
 157         fprintf_filtered (stream, "%s@entry",
 158                           exp->elts[pc + 1].symbol->print_name ());
 159       }
 160       return;
 161
 162     case OP_LAST:
 163       (*pos) += 2;
 164       fprintf_filtered (stream, "$%d",
 165                         longest_to_int (exp->elts[pc + 1].longconst));
 166       return;
 167
 168     case OP_REGISTER:
 169       {
 170         const char *name = &exp->elts[pc + 2].string;
 171
 172         (*pos) += 3 + BYTES_TO_EXP_ELEM (exp->elts[pc + 1].longconst + 1);
 173         fprintf_filtered (stream, "$%s", name);
 174         return;
 175       }
 176
 177     case OP_BOOL:
 178       (*pos) += 2;
 179       fprintf_filtered (stream, "%s",
 180                         longest_to_int (exp->elts[pc + 1].longconst)
 181                         ? "TRUE" : "FALSE");
 182       return;
 183
 184     case OP_INTERNALVAR:
 185       (*pos) += 2;
 186       fprintf_filtered (stream, "$%s",
 187                         internalvar_name (exp->elts[pc + 1].internalvar));
 188       return;
 189
 190     case OP_FUNCALL:
 191     case OP_F77_UNDETERMINED_ARGLIST:
 192       (*pos) += 2;
 193       nargs = longest_to_int (exp->elts[pc + 1].longconst);
 194       print_subexp (exp, pos, stream, PREC_SUFFIX);
 195       fputs_filtered (" (", stream);
 196       for (tem = 0; tem < nargs; tem++)
 197         {
 198           if (tem != 0)
 199             fputs_filtered (", ", stream);
 200           print_subexp (exp, pos, stream, PREC_ABOVE_COMMA);
 201         }
 202       fputs_filtered (")", stream);
 203       return;
 204
 205     case OP_NAME:
 206       nargs = longest_to_int (exp->elts[pc + 1].longconst);
 207       (*pos) += 3 + BYTES_TO_EXP_ELEM (nargs + 1);
 208       fputs_filtered (&exp->elts[pc + 2].string, stream);
 209       return;
 210
 211     case OP_STRING:
 212       {
 213         struct value_print_options opts;
 214
 215         nargs = longest_to_int (exp->elts[pc + 1].longconst);
 216         (*pos) += 3 + BYTES_TO_EXP_ELEM (nargs + 1);
 217         /* LA_PRINT_STRING will print using the current repeat count threshold.
 218            If necessary, we can temporarily set it to zero, or pass it as an
 219            additional parameter to LA_PRINT_STRING.  -fnf */
 220         get_user_print_options (&opts);
 221         LA_PRINT_STRING (stream, builtin_type (exp->gdbarch)->builtin_char,
 222                          (gdb_byte *) &exp->elts[pc + 2].string, nargs,
 223                          NULL, 0, &opts);
 224       }
 225       return;
 226
 227     case OP_OBJC_NSSTRING:      /* Objective-C Foundation Class
 228                                    NSString constant.  */
 229       {
 230         struct value_print_options opts;
 231
 232         nargs = longest_to_int (exp->elts[pc + 1].longconst);
 233         (*pos) += 3 + BYTES_TO_EXP_ELEM (nargs + 1);
 234         fputs_filtered ("@\"", stream);
 235         get_user_print_options (&opts);
 236         LA_PRINT_STRING (stream, builtin_type (exp->gdbarch)->builtin_char,
 237                          (gdb_byte *) &exp->elts[pc + 2].string, nargs,
 238                          NULL, 0, &opts);
 239         fputs_filtered ("\"", stream);
 240       }
 241       return;
 242
 243     case OP_OBJC_MSGCALL:
 244       {                 /* Objective C message (method) call.  */
 245         (*pos) += 3;
 246         nargs = longest_to_int (exp->elts[pc + 2].longconst);
 247         fprintf_unfiltered (stream, "[");
 248         print_subexp (exp, pos, stream, PREC_SUFFIX);
 249         gdb::unique_xmalloc_ptr<char> selector
 250           = target_read_string (exp->elts[pc + 1].longconst, 1024);
 251         if (selector == nullptr)
 252           error (_("bad selector"));
 253         if (nargs)
 254           {
 255             char *s, *nextS;
 256
 257             s = selector.get ();
 258             for (tem = 0; tem < nargs; tem++)
 259               {
 260                 nextS = strchr (s, ':');
 261                 gdb_assert (nextS);     /* Make sure we found ':'.  */
 262                 *nextS = '\0';
 263                 fprintf_unfiltered (stream, " %s: ", s);
 264                 s = nextS + 1;
 265                 print_subexp (exp, pos, stream, PREC_ABOVE_COMMA);
 266               }
 267           }
 268         else
 269           {
 270             fprintf_unfiltered (stream, " %s", selector.get ());
 271           }
 272         fprintf_unfiltered (stream, "]");
 273         return;
 274       }
 275
 276     case OP_ARRAY:
 277       (*pos) += 3;
 278       nargs = longest_to_int (exp->elts[pc + 2].longconst);
 279       nargs -= longest_to_int (exp->elts[pc + 1].longconst);
 280       nargs++;
 281       tem = 0;
 282       if (exp->elts[pc + 4].opcode == OP_LONG
 283           && exp->elts[pc + 5].type
 284              == builtin_type (exp->gdbarch)->builtin_char
 285           && exp->language_defn->la_language == language_c)
 286         {
 287           /* Attempt to print C character arrays using string syntax.
 288              Walk through the args, picking up one character from each
 289              of the OP_LONG expression elements.  If any array element
 290              does not match our expection of what we should find for
 291              a simple string, revert back to array printing.  Note that
 292              the last expression element is an explicit null terminator
 293              byte, which doesn't get printed.  */
 294           tempstr = (char *) alloca (nargs);
 295           pc += 4;
 296           while (tem < nargs)
 297             {
 298               if (exp->elts[pc].opcode != OP_LONG
 299                   || exp->elts[pc + 1].type
 300                      != builtin_type (exp->gdbarch)->builtin_char)
 301                 {
 302                   /* Not a simple array of char, use regular array
 303                      printing.  */
 304                   tem = 0;
 305                   break;
 306                 }
 307               else
 308                 {
 309                   tempstr[tem++] =
 310                     longest_to_int (exp->elts[pc + 2].longconst);
 311                   pc += 4;
 312                 }
 313             }
 314         }
 315       if (tem > 0)
 316         {
 317           struct value_print_options opts;
 318
 319           get_user_print_options (&opts);
 320           LA_PRINT_STRING (stream, builtin_type (exp->gdbarch)->builtin_char,
 321                            (gdb_byte *) tempstr, nargs - 1, NULL, 0, &opts);
 322           (*pos) = pc;
 323         }
 324       else
 325         {
 326           fputs_filtered (" {", stream);
 327           for (tem = 0; tem < nargs; tem++)
 328             {
 329               if (tem != 0)
 330                 {
 331                   fputs_filtered (", ", stream);
 332                 }
 333               print_subexp (exp, pos, stream, PREC_ABOVE_COMMA);
 334             }
 335           fputs_filtered ("}", stream);
 336         }
 337       return;
 338
 339     case TERNOP_COND:
 340       if ((int) prec > (int) PREC_COMMA)
 341         fputs_filtered ("(", stream);
 342       /* Print the subexpressions, forcing parentheses
 343          around any binary operations within them.
 344          This is more parentheses than are strictly necessary,
 345          but it looks clearer.  */
 346       print_subexp (exp, pos, stream, PREC_HYPER);
 347       fputs_filtered (" ? ", stream);
 348       print_subexp (exp, pos, stream, PREC_HYPER);
 349       fputs_filtered (" : ", stream);
 350       print_subexp (exp, pos, stream, PREC_HYPER);
 351       if ((int) prec > (int) PREC_COMMA)
 352         fputs_filtered (")", stream);
 353       return;
 354
 355     case TERNOP_SLICE:
 356       print_subexp (exp, pos, stream, PREC_SUFFIX);
 357       fputs_filtered ("(", stream);
 358       print_subexp (exp, pos, stream, PREC_ABOVE_COMMA);
 359       fputs_filtered (opcode == TERNOP_SLICE ? " : " : " UP ", stream);
 360       print_subexp (exp, pos, stream, PREC_ABOVE_COMMA);
 361       fputs_filtered (")", stream);
 362       return;
 363
 364     case STRUCTOP_STRUCT:
 365       tem = longest_to_int (exp->elts[pc + 1].longconst);
 366       (*pos) += 3 + BYTES_TO_EXP_ELEM (tem + 1);
 367       print_subexp (exp, pos, stream, PREC_SUFFIX);
 368       fputs_filtered (".", stream);
 369       fputs_filtered (&exp->elts[pc + 2].string, stream);
 370       return;
 371
 372       /* Will not occur for Modula-2.  */
 373     case STRUCTOP_PTR:
 374       tem = longest_to_int (exp->elts[pc + 1].longconst);
 375       (*pos) += 3 + BYTES_TO_EXP_ELEM (tem + 1);
 376       print_subexp (exp, pos, stream, PREC_SUFFIX);
 377       fputs_filtered ("->", stream);
 378       fputs_filtered (&exp->elts[pc + 2].string, stream);
 379       return;
 380
 381     case STRUCTOP_MEMBER:
 382       print_subexp (exp, pos, stream, PREC_SUFFIX);
 383       fputs_filtered (".*", stream);
 384       print_subexp (exp, pos, stream, PREC_SUFFIX);
 385       return;
 386
 387     case STRUCTOP_MPTR:
 388       print_subexp (exp, pos, stream, PREC_SUFFIX);
 389       fputs_filtered ("->*", stream);
 390       print_subexp (exp, pos, stream, PREC_SUFFIX);
 391       return;
 392
 393     case BINOP_SUBSCRIPT:
 394       print_subexp (exp, pos, stream, PREC_SUFFIX);
 395       fputs_filtered ("[", stream);
 396       print_subexp (exp, pos, stream, PREC_ABOVE_COMMA);
 397       fputs_filtered ("]", stream);
 398       return;
 399
 400     case UNOP_POSTINCREMENT:
 401       print_subexp (exp, pos, stream, PREC_SUFFIX);
 402       fputs_filtered ("++", stream);
 403       return;
 404
 405     case UNOP_POSTDECREMENT:
 406       print_subexp (exp, pos, stream, PREC_SUFFIX);
 407       fputs_filtered ("--", stream);
 408       return;
 409
 410     case UNOP_CAST:
 411       (*pos) += 2;
 412       if ((int) prec > (int) PREC_PREFIX)
 413         fputs_filtered ("(", stream);
 414       fputs_filtered ("(", stream);
 415       type_print (exp->elts[pc + 1].type, "", stream, 0);
 416       fputs_filtered (") ", stream);
 417       print_subexp (exp, pos, stream, PREC_PREFIX);
 418       if ((int) prec > (int) PREC_PREFIX)
 419         fputs_filtered (")", stream);
 420       return;
 421
 422     case UNOP_CAST_TYPE:
 423       if ((int) prec > (int) PREC_PREFIX)
 424         fputs_filtered ("(", stream);
 425       fputs_filtered ("(", stream);
 426       print_subexp (exp, pos, stream, PREC_PREFIX);
 427       fputs_filtered (") ", stream);
 428       print_subexp (exp, pos, stream, PREC_PREFIX);
 429       if ((int) prec > (int) PREC_PREFIX)
 430         fputs_filtered (")", stream);
 431       return;
 432
 433     case UNOP_DYNAMIC_CAST:
 434     case UNOP_REINTERPRET_CAST:
 435       fputs_filtered (opcode == UNOP_DYNAMIC_CAST ? "dynamic_cast"
 436                       : "reinterpret_cast", stream);
 437       fputs_filtered ("<", stream);
 438       print_subexp (exp, pos, stream, PREC_PREFIX);
 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 (exp->elts[pc + 1].type->code () == 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_no_prettyformat_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_TYPE:
 475       if ((int) prec > (int) PREC_PREFIX)
 476         fputs_filtered ("(", stream);
 477       fputs_filtered ("{", stream);
 478       print_subexp (exp, pos, stream, PREC_PREFIX);
 479       fputs_filtered ("} ", stream);
 480       print_subexp (exp, pos, stream, PREC_PREFIX);
 481       if ((int) prec > (int) PREC_PREFIX)
 482         fputs_filtered (")", stream);
 483       return;
 484
 485     case BINOP_ASSIGN_MODIFY:
 486       opcode = exp->elts[pc + 1].opcode;
 487       (*pos) += 2;
 488       myprec = PREC_ASSIGN;
 489       assoc = 1;
 490       assign_modify = 1;
 491       op_str = "???";
 492       for (tem = 0; op_print_tab[tem].opcode != OP_NULL; tem++)
 493         if (op_print_tab[tem].opcode == opcode)
 494           {
 495             op_str = op_print_tab[tem].string;
 496             break;
 497           }
 498       if (op_print_tab[tem].opcode != opcode)
 499         /* Not found; don't try to keep going because we don't know how
 500            to interpret further elements.  */
 501         error (_("Invalid expression"));
 502       break;
 503
 504       /* C++ ops */
 505
 506     case OP_THIS:
 507       ++(*pos);
 508       if (exp->language_defn->name_of_this () != NULL)
 509         fputs_filtered (exp->language_defn->name_of_this (), stream);
 510       else
 511         fprintf_styled (stream, metadata_style.style (),
 512                         _("<language %s has no 'this'>"),
 513                         exp->language_defn->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         type_instance_flags flags
 544           = (type_instance_flag_value) longest_to_int (exp->elts[pc + 1].longconst);
 545         LONGEST count = exp->elts[pc + 2].longconst;
 546
 547         /* The FLAGS.  */
 548         (*pos)++;
 549         /* The COUNT.  */
 550         (*pos)++;
 551         fputs_unfiltered ("TypeInstance(", stream);
 552         while (count-- > 0)
 553           {
 554             type_print (exp->elts[(*pos)++].type, "", stream, 0);
 555             if (count > 0)
 556               fputs_unfiltered (",", stream);
 557           }
 558         fputs_unfiltered (",", stream);
 559         /* Ending COUNT and ending TYPE_INSTANCE.  */
 560         (*pos) += 2;
 561         print_subexp (exp, pos, stream, PREC_PREFIX);
 562
 563         if (flags & TYPE_INSTANCE_FLAG_CONST)
 564           fputs_unfiltered (",const", stream);
 565         if (flags & TYPE_INSTANCE_FLAG_VOLATILE)
 566           fputs_unfiltered (",volatile", stream);
 567
 568         fputs_unfiltered (")", stream);
 569         return;
 570       }
 571
 572     case OP_RANGE:
 573       {
 574         enum range_type range_type;
 575
 576         range_type = (enum range_type)
 577           longest_to_int (exp->elts[pc + 1].longconst);
 578         *pos += 2;
 579
 580         if (range_type == NONE_BOUND_DEFAULT_EXCLUSIVE
 581             || range_type == LOW_BOUND_DEFAULT_EXCLUSIVE)
 582           fputs_filtered ("EXCLUSIVE_", stream);
 583         fputs_filtered ("RANGE(", stream);
 584         if (range_type == HIGH_BOUND_DEFAULT
 585             || range_type == NONE_BOUND_DEFAULT
 586             || range_type == NONE_BOUND_DEFAULT_EXCLUSIVE)
 587           print_subexp (exp, pos, stream, PREC_ABOVE_COMMA);
 588         fputs_filtered ("..", stream);
 589         if (range_type == LOW_BOUND_DEFAULT
 590             || range_type == NONE_BOUND_DEFAULT)
 591           print_subexp (exp, pos, stream, PREC_ABOVE_COMMA);
 592         fputs_filtered (")", stream);
 593         return;
 594       }
 595
 596       /* Default ops */
 597
 598     default:
 599       op_str = "???";
 600       for (tem = 0; op_print_tab[tem].opcode != OP_NULL; tem++)
 601         if (op_print_tab[tem].opcode == opcode)
 602           {
 603             op_str = op_print_tab[tem].string;
 604             myprec = op_print_tab[tem].precedence;
 605             assoc = op_print_tab[tem].right_assoc;
 606             break;
 607           }
 608       if (op_print_tab[tem].opcode != opcode)
 609         /* Not found; don't try to keep going because we don't know how
 610            to interpret further elements.  For example, this happens
 611            if opcode is OP_TYPE.  */
 612         error (_("Invalid expression"));
 613     }
 614
 615   /* Note that PREC_BUILTIN will always emit parentheses.  */
 616   if ((int) myprec < (int) prec)
 617     fputs_filtered ("(", stream);
 618   if ((int) opcode > (int) BINOP_END)
 619     {
 620       if (assoc)
 621         {
 622           /* Unary postfix operator.  */
 623           print_subexp (exp, pos, stream, PREC_SUFFIX);
 624           fputs_filtered (op_str, stream);
 625         }
 626       else
 627         {
 628           /* Unary prefix operator.  */
 629           fputs_filtered (op_str, stream);
 630           if (myprec == PREC_BUILTIN_FUNCTION)
 631             fputs_filtered ("(", stream);
 632           print_subexp (exp, pos, stream, PREC_PREFIX);
 633           if (myprec == PREC_BUILTIN_FUNCTION)
 634             fputs_filtered (")", stream);
 635         }
 636     }
 637   else
 638     {
 639       /* Binary operator.  */
 640       /* Print left operand.
 641          If operator is right-associative,
 642          increment precedence for this operand.  */
 643       print_subexp (exp, pos, stream,
 644                     (enum precedence) ((int) myprec + assoc));
 645       /* Print the operator itself.  */
 646       if (assign_modify)
 647         fprintf_filtered (stream, " %s= ", op_str);
 648       else if (op_str[0] == ',')
 649         fprintf_filtered (stream, "%s ", op_str);
 650       else
 651         fprintf_filtered (stream, " %s ", op_str);
 652       /* Print right operand.
 653          If operator is left-associative,
 654          increment precedence for this operand.  */
 655       print_subexp (exp, pos, stream,
 656                     (enum precedence) ((int) myprec + !assoc));
 657     }
 658
 659   if ((int) myprec < (int) prec)
 660     fputs_filtered (")", stream);
 661 }
 662
 663 /* Return the operator corresponding to opcode OP as
 664    a string.   NULL indicates that the opcode was not found in the
 665    current language table.  */
 666 const char *
 667 op_string (enum exp_opcode op)
 668 {
 669   int tem;
 670   const struct op_print *op_print_tab;
 671
 672   op_print_tab = current_language->opcode_print_table ();
 673   for (tem = 0; op_print_tab[tem].opcode != OP_NULL; tem++)
 674     if (op_print_tab[tem].opcode == op)
 675       return op_print_tab[tem].string;
 676   return NULL;
 677 }
 678
 679 /* Support for dumping the raw data from expressions in a human readable
 680    form.  */
 681
 682 static int dump_subexp_body (struct expression *exp, struct ui_file *, int);
 683
 684 /* Name for OPCODE, when it appears in expression EXP.  */
 685
 686 const char *
 687 op_name (struct expression *exp, enum exp_opcode opcode)
 688 {
 689   if (opcode >= OP_UNUSED_LAST)
 690     {
 691       char *cell = get_print_cell ();
 692       xsnprintf (cell, PRINT_CELL_SIZE, "unknown opcode: %u",
 693                  unsigned (opcode));
 694       return cell;
 695     }
 696   return exp->language_defn->expression_ops ()->op_name (opcode);
 697 }
 698
 699 /* Default name for the standard operator OPCODE (i.e., one defined in
 700    the definition of enum exp_opcode).  */
 701
 702 const char *
 703 op_name_standard (enum exp_opcode opcode)
 704 {
 705   switch (opcode)
 706     {
 707     default:
 708       {
 709         static char buf[30];
 710
 711         xsnprintf (buf, sizeof (buf), "<unknown %d>", opcode);
 712         return buf;
 713       }
 714 #define OP(name)        \
 715     case name:          \
 716       return #name ;
 717 #include "std-operator.def"
 718 #undef OP
 719     }
 720 }
 721
 722 /* Print a raw dump of expression EXP to STREAM.
 723    NOTE, if non-NULL, is printed as extra explanatory text.  */
 724
 725 void
 726 dump_raw_expression (struct expression *exp, struct ui_file *stream,
 727                      const char *note)
 728 {
 729   int elt;
 730   char *eltscan;
 731   int eltsize;
 732
 733   fprintf_filtered (stream, "Dump of expression @ ");
 734   gdb_print_host_address (exp, stream);
 735   if (note)
 736     fprintf_filtered (stream, ", %s:", note);
 737   fprintf_filtered (stream, "\n\tLanguage %s, %d elements, %ld bytes each.\n",
 738                     exp->language_defn->name (), exp->nelts,
 739                     (long) sizeof (union exp_element));
 740   fprintf_filtered (stream, "\t%5s  %20s  %16s  %s\n", "Index", "Opcode",
 741                     "Hex Value", "String Value");
 742   for (elt = 0; elt < exp->nelts; elt++)
 743     {
 744       fprintf_filtered (stream, "\t%5d  ", elt);
 745
 746       const char *opcode_name = op_name (exp, exp->elts[elt].opcode);
 747       fprintf_filtered (stream, "%20s  ", opcode_name);
 748
 749       print_longest (stream, 'd', 0, exp->elts[elt].longconst);
 750       fprintf_filtered (stream, "  ");
 751
 752       for (eltscan = (char *) &exp->elts[elt],
 753            eltsize = sizeof (union exp_element);
 754            eltsize-- > 0;
 755            eltscan++)
 756         {
 757           fprintf_filtered (stream, "%c",
 758                             isprint (*eltscan) ? (*eltscan & 0xFF) : '.');
 759         }
 760       fprintf_filtered (stream, "\n");
 761     }
 762 }
 763
 764 /* Dump the subexpression of prefix expression EXP whose operator is at
 765    position ELT onto STREAM.  Returns the position of the next
 766    subexpression in EXP.  */
 767
 768 int
 769 dump_subexp (struct expression *exp, struct ui_file *stream, int elt)
 770 {
 771   static int indent = 0;
 772   int i;
 773
 774   fprintf_filtered (stream, "\n");
 775   fprintf_filtered (stream, "\t%5d  ", elt);
 776
 777   for (i = 1; i <= indent; i++)
 778     fprintf_filtered (stream, " ");
 779   indent += 2;
 780
 781   fprintf_filtered (stream, "%-20s  ", op_name (exp, exp->elts[elt].opcode));
 782
 783   elt = dump_subexp_body (exp, stream, elt);
 784
 785   indent -= 2;
 786
 787   return elt;
 788 }
 789
 790 /* Dump the operands of prefix expression EXP whose opcode is at
 791    position ELT onto STREAM.  Returns the position of the next
 792    subexpression in EXP.  */
 793
 794 static int
 795 dump_subexp_body (struct expression *exp, struct ui_file *stream, int elt)
 796 {
 797   return exp->language_defn->expression_ops ()->dump_subexp_body (exp, stream,
 798                                                                   elt);
 799 }
 800
 801 /* Default value for subexp_body in exp_descriptor vector.  */
 802
 803 int
 804 dump_subexp_body_standard (struct expression *exp,
 805                            struct ui_file *stream, int elt)
 806 {
 807   int opcode = exp->elts[elt++].opcode;
 808
 809   switch (opcode)
 810     {
 811     case TERNOP_COND:
 812     case TERNOP_SLICE:
 813       elt = dump_subexp (exp, stream, elt);
 814       /* FALL THROUGH */
 815     case BINOP_ADD:
 816     case BINOP_SUB:
 817     case BINOP_MUL:
 818     case BINOP_DIV:
 819     case BINOP_REM:
 820     case BINOP_MOD:
 821     case BINOP_LSH:
 822     case BINOP_RSH:
 823     case BINOP_LOGICAL_AND:
 824     case BINOP_LOGICAL_OR:
 825     case BINOP_BITWISE_AND:
 826     case BINOP_BITWISE_IOR:
 827     case BINOP_BITWISE_XOR:
 828     case BINOP_EQUAL:
 829     case BINOP_NOTEQUAL:
 830     case BINOP_LESS:
 831     case BINOP_GTR:
 832     case BINOP_LEQ:
 833     case BINOP_GEQ:
 834     case BINOP_REPEAT:
 835     case BINOP_ASSIGN:
 836     case BINOP_COMMA:
 837     case BINOP_SUBSCRIPT:
 838     case BINOP_EXP:
 839     case BINOP_MIN:
 840     case BINOP_MAX:
 841     case BINOP_INTDIV:
 842     case BINOP_ASSIGN_MODIFY:
 843     case BINOP_VAL:
 844     case BINOP_CONCAT:
 845     case BINOP_END:
 846     case STRUCTOP_MEMBER:
 847     case STRUCTOP_MPTR:
 848       elt = dump_subexp (exp, stream, elt);
 849       /* FALL THROUGH */
 850     case UNOP_NEG:
 851     case UNOP_LOGICAL_NOT:
 852     case UNOP_COMPLEMENT:
 853     case UNOP_IND:
 854     case UNOP_ADDR:
 855     case UNOP_PREINCREMENT:
 856     case UNOP_POSTINCREMENT:
 857     case UNOP_PREDECREMENT:
 858     case UNOP_POSTDECREMENT:
 859     case UNOP_SIZEOF:
 860     case UNOP_ALIGNOF:
 861     case UNOP_PLUS:
 862     case UNOP_CAP:
 863     case UNOP_CHR:
 864     case UNOP_ORD:
 865     case UNOP_ABS:
 866     case UNOP_FLOAT:
 867     case UNOP_HIGH:
 868     case UNOP_MAX:
 869     case UNOP_MIN:
 870     case UNOP_ODD:
 871     case UNOP_TRUNC:
 872       elt = dump_subexp (exp, stream, elt);
 873       break;
 874     case OP_LONG:
 875       fprintf_filtered (stream, "Type @");
 876       gdb_print_host_address (exp->elts[elt].type, stream);
 877       fprintf_filtered (stream, " (");
 878       type_print (exp->elts[elt].type, NULL, stream, 0);
 879       fprintf_filtered (stream, "), value %ld (0x%lx)",
 880                         (long) exp->elts[elt + 1].longconst,
 881                         (long) exp->elts[elt + 1].longconst);
 882       elt += 3;
 883       break;
 884     case OP_FLOAT:
 885       fprintf_filtered (stream, "Type @");
 886       gdb_print_host_address (exp->elts[elt].type, stream);
 887       fprintf_filtered (stream, " (");
 888       type_print (exp->elts[elt].type, NULL, stream, 0);
 889       fprintf_filtered (stream, "), value ");
 890       print_floating (exp->elts[elt + 1].floatconst,
 891                       exp->elts[elt].type, stream);
 892       elt += 3;
 893       break;
 894     case OP_VAR_VALUE:
 895       fprintf_filtered (stream, "Block @");
 896       gdb_print_host_address (exp->elts[elt].block, stream);
 897       fprintf_filtered (stream, ", symbol @");
 898       gdb_print_host_address (exp->elts[elt + 1].symbol, stream);
 899       fprintf_filtered (stream, " (%s)",
 900                         exp->elts[elt + 1].symbol->print_name ());
 901       elt += 3;
 902       break;
 903     case OP_VAR_MSYM_VALUE:
 904       fprintf_filtered (stream, "Objfile @");
 905       gdb_print_host_address (exp->elts[elt].objfile, stream);
 906       fprintf_filtered (stream, ", msymbol @");
 907       gdb_print_host_address (exp->elts[elt + 1].msymbol, stream);
 908       fprintf_filtered (stream, " (%s)",
 909                         exp->elts[elt + 1].msymbol->print_name ());
 910       elt += 3;
 911       break;
 912     case OP_VAR_ENTRY_VALUE:
 913       fprintf_filtered (stream, "Entry value of symbol @");
 914       gdb_print_host_address (exp->elts[elt].symbol, stream);
 915       fprintf_filtered (stream, " (%s)",
 916                         exp->elts[elt].symbol->print_name ());
 917       elt += 2;
 918       break;
 919     case OP_LAST:
 920       fprintf_filtered (stream, "History element %ld",
 921                         (long) exp->elts[elt].longconst);
 922       elt += 2;
 923       break;
 924     case OP_REGISTER:
 925       fprintf_filtered (stream, "Register $%s", &exp->elts[elt + 1].string);
 926       elt += 3 + BYTES_TO_EXP_ELEM (exp->elts[elt].longconst + 1);
 927       break;
 928     case OP_INTERNALVAR:
 929       fprintf_filtered (stream, "Internal var @");
 930       gdb_print_host_address (exp->elts[elt].internalvar, stream);
 931       fprintf_filtered (stream, " (%s)",
 932                         internalvar_name (exp->elts[elt].internalvar));
 933       elt += 2;
 934       break;
 935     case OP_FUNCALL:
 936     case OP_F77_UNDETERMINED_ARGLIST:
 937       {
 938         int i, nargs;
 939
 940         nargs = longest_to_int (exp->elts[elt].longconst);
 941
 942         fprintf_filtered (stream, "Number of args: %d", nargs);
 943         elt += 2;
 944
 945         for (i = 1; i <= nargs + 1; i++)
 946           elt = dump_subexp (exp, stream, elt);
 947       }
 948       break;
 949     case OP_ARRAY:
 950       {
 951         int lower, upper;
 952         int i;
 953
 954         lower = longest_to_int (exp->elts[elt].longconst);
 955         upper = longest_to_int (exp->elts[elt + 1].longconst);
 956
 957         fprintf_filtered (stream, "Bounds [%d:%d]", lower, upper);
 958         elt += 3;
 959
 960         for (i = 1; i <= upper - lower + 1; i++)
 961           elt = dump_subexp (exp, stream, elt);
 962       }
 963       break;
 964     case UNOP_DYNAMIC_CAST:
 965     case UNOP_REINTERPRET_CAST:
 966     case UNOP_CAST_TYPE:
 967     case UNOP_MEMVAL_TYPE:
 968       fprintf_filtered (stream, " (");
 969       elt = dump_subexp (exp, stream, elt);
 970       fprintf_filtered (stream, ")");
 971       elt = dump_subexp (exp, stream, elt);
 972       break;
 973     case UNOP_MEMVAL:
 974     case UNOP_CAST:
 975       fprintf_filtered (stream, "Type @");
 976       gdb_print_host_address (exp->elts[elt].type, stream);
 977       fprintf_filtered (stream, " (");
 978       type_print (exp->elts[elt].type, NULL, stream, 0);
 979       fprintf_filtered (stream, ")");
 980       elt = dump_subexp (exp, stream, elt + 2);
 981       break;
 982     case OP_TYPE:
 983       fprintf_filtered (stream, "Type @");
 984       gdb_print_host_address (exp->elts[elt].type, stream);
 985       fprintf_filtered (stream, " (");
 986       type_print (exp->elts[elt].type, NULL, stream, 0);
 987       fprintf_filtered (stream, ")");
 988       elt += 2;
 989       break;
 990     case OP_TYPEOF:
 991     case OP_DECLTYPE:
 992       fprintf_filtered (stream, "Typeof (");
 993       elt = dump_subexp (exp, stream, elt);
 994       fprintf_filtered (stream, ")");
 995       break;
 996     case OP_TYPEID:
 997       fprintf_filtered (stream, "typeid (");
 998       elt = dump_subexp (exp, stream, elt);
 999       fprintf_filtered (stream, ")");
1000       break;
1001     case STRUCTOP_STRUCT:
1002     case STRUCTOP_PTR:
1003       {
1004         char *elem_name;
1005         int len;
1006
1007         len = longest_to_int (exp->elts[elt].longconst);
1008         elem_name = &exp->elts[elt + 1].string;
1009
1010         fprintf_filtered (stream, "Element name: `%.*s'", len, elem_name);
1011         elt = dump_subexp (exp, stream, elt + 3 + BYTES_TO_EXP_ELEM (len + 1));
1012       }
1013       break;
1014     case OP_SCOPE:
1015       {
1016         char *elem_name;
1017         int len;
1018
1019         fprintf_filtered (stream, "Type @");
1020         gdb_print_host_address (exp->elts[elt].type, stream);
1021         fprintf_filtered (stream, " (");
1022         type_print (exp->elts[elt].type, NULL, stream, 0);
1023         fprintf_filtered (stream, ") ");
1024
1025         len = longest_to_int (exp->elts[elt + 1].longconst);
1026         elem_name = &exp->elts[elt + 2].string;
1027
1028         fprintf_filtered (stream, "Field name: `%.*s'", len, elem_name);
1029         elt += 4 + BYTES_TO_EXP_ELEM (len + 1);
1030       }
1031       break;
1032
1033     case OP_FUNC_STATIC_VAR:
1034       {
1035         int len = longest_to_int (exp->elts[elt].longconst);
1036         const char *var_name = &exp->elts[elt + 1].string;
1037         fprintf_filtered (stream, "Field name: `%.*s'", len, var_name);
1038         elt += 3 + BYTES_TO_EXP_ELEM (len + 1);
1039       }
1040       break;
1041
1042     case TYPE_INSTANCE:
1043       {
1044         type_instance_flags flags
1045           = (type_instance_flag_value) longest_to_int (exp->elts[elt++].longconst);
1046         LONGEST len = exp->elts[elt++].longconst;
1047         fprintf_filtered (stream, "%s TypeInstance: ", plongest (len));
1048         while (len-- > 0)
1049           {
1050             fprintf_filtered (stream, "Type @");
1051             gdb_print_host_address (exp->elts[elt].type, stream);
1052             fprintf_filtered (stream, " (");
1053             type_print (exp->elts[elt].type, NULL, stream, 0);
1054             fprintf_filtered (stream, ")");
1055             elt++;
1056             if (len > 0)
1057               fputs_filtered (", ", stream);
1058           }
1059
1060         fprintf_filtered (stream, " Flags: %s (", hex_string (flags));
1061         bool space = false;
1062         auto print_one = [&] (const char *mod)
1063           {
1064             if (space)
1065               fputs_filtered (" ", stream);
1066             space = true;
1067             fprintf_filtered (stream, "%s", mod);
1068           };
1069         if (flags & TYPE_INSTANCE_FLAG_CONST)
1070           print_one ("const");
1071         if (flags & TYPE_INSTANCE_FLAG_VOLATILE)
1072           print_one ("volatile");
1073         fprintf_filtered (stream, ")");
1074
1075         /* Ending LEN and ending TYPE_INSTANCE.  */
1076         elt += 2;
1077         elt = dump_subexp (exp, stream, elt);
1078       }
1079       break;
1080     case OP_STRING:
1081       {
1082         LONGEST len = exp->elts[elt].longconst;
1083         LONGEST type = exp->elts[elt + 1].longconst;
1084
1085         fprintf_filtered (stream, "Language-specific string type: %s",
1086                           plongest (type));
1087
1088         /* Skip length.  */
1089         elt += 1;
1090
1091         /* Skip string content. */
1092         elt += BYTES_TO_EXP_ELEM (len);
1093
1094         /* Skip length and ending OP_STRING. */
1095         elt += 2;
1096       }
1097       break;
1098     case OP_RANGE:
1099       {
1100         enum range_type range_type;
1101
1102         range_type = (enum range_type)
1103           longest_to_int (exp->elts[elt].longconst);
1104         elt += 2;
1105
1106         switch (range_type)
1107           {
1108           case BOTH_BOUND_DEFAULT:
1109             fputs_filtered ("Range '..'", stream);
1110             break;
1111           case LOW_BOUND_DEFAULT:
1112             fputs_filtered ("Range '..EXP'", stream);
1113             break;
1114           case LOW_BOUND_DEFAULT_EXCLUSIVE:
1115             fputs_filtered ("ExclusiveRange '..EXP'", stream);
1116             break;
1117           case HIGH_BOUND_DEFAULT:
1118             fputs_filtered ("Range 'EXP..'", stream);
1119             break;
1120           case NONE_BOUND_DEFAULT:
1121             fputs_filtered ("Range 'EXP..EXP'", stream);
1122             break;
1123           case NONE_BOUND_DEFAULT_EXCLUSIVE:
1124             fputs_filtered ("ExclusiveRange 'EXP..EXP'", stream);
1125             break;
1126           default:
1127             fputs_filtered ("Invalid Range!", stream);
1128             break;
1129           }
1130
1131         if (range_type == HIGH_BOUND_DEFAULT
1132             || range_type == NONE_BOUND_DEFAULT)
1133           elt = dump_subexp (exp, stream, elt);
1134         if (range_type == LOW_BOUND_DEFAULT
1135             || range_type == NONE_BOUND_DEFAULT)
1136           elt = dump_subexp (exp, stream, elt);
1137       }
1138       break;
1139
1140     default:
1141     case OP_NULL:
1142     case MULTI_SUBSCRIPT:
1143     case OP_COMPLEX:
1144     case OP_BOOL:
1145     case OP_M2_STRING:
1146     case OP_THIS:
1147     case OP_NAME:
1148       fprintf_filtered (stream, "Unknown format");
1149     }
1150
1151   return elt;
1152 }
1153
1154 void
1155 dump_prefix_expression (struct expression *exp, struct ui_file *stream)
1156 {
1157   int elt;
1158
1159   fprintf_filtered (stream, "Dump of expression @ ");
1160   gdb_print_host_address (exp, stream);
1161   fputs_filtered (", after conversion to prefix form:\nExpression: `", stream);
1162   print_expression (exp, stream);
1163   fprintf_filtered (stream, "'\n\tLanguage %s, %d elements, %ld bytes each.\n",
1164                     exp->language_defn->name (), exp->nelts,
1165                     (long) sizeof (union exp_element));
1166   fputs_filtered ("\n", stream);
1167
1168   for (elt = 0; elt < exp->nelts;)
1169     elt = dump_subexp (exp, stream, elt);
1170   fputs_filtered ("\n", stream);
1171 }