gdb/expop.h

   1 /* Definitions for expressions in GDB
   2
   3    Copyright (C) 2020-2022 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 #ifndef EXPOP_H
  21 #define EXPOP_H
  22
  23 #include "block.h"
  24 #include "c-lang.h"
  25 #include "cp-abi.h"
  26 #include "expression.h"
  27 #include "objfiles.h"
  28 #include "gdbsupport/traits.h"
  29 #include "gdbsupport/enum-flags.h"
  30
  31 struct agent_expr;
  32 struct axs_value;
  33
  34 extern void gen_expr_binop (struct expression *exp,
  35                             enum exp_opcode op,
  36                             expr::operation *lhs, expr::operation *rhs,
  37                             struct agent_expr *ax, struct axs_value *value);
  38 extern void gen_expr_structop (struct expression *exp,
  39                                enum exp_opcode op,
  40                                expr::operation *lhs,
  41                                const char *name,
  42                                struct agent_expr *ax, struct axs_value *value);
  43 extern void gen_expr_unop (struct expression *exp,
  44                            enum exp_opcode op,
  45                            expr::operation *lhs,
  46                            struct agent_expr *ax, struct axs_value *value);
  47
  48 extern struct value *eval_op_scope (struct type *expect_type,
  49                                     struct expression *exp,
  50                                     enum noside noside,
  51                                     struct type *type, const char *string);
  52 extern struct value *eval_op_var_msym_value (struct type *expect_type,
  53                                              struct expression *exp,
  54                                              enum noside noside,
  55                                              bool outermost_p,
  56                                              bound_minimal_symbol msymbol);
  57 extern struct value *eval_op_var_entry_value (struct type *expect_type,
  58                                               struct expression *exp,
  59                                               enum noside noside, symbol *sym);
  60 extern struct value *eval_op_func_static_var (struct type *expect_type,
  61                                               struct expression *exp,
  62                                               enum noside noside,
  63                                               value *func, const char *var);
  64 extern struct value *eval_op_register (struct type *expect_type,
  65                                        struct expression *exp,
  66                                        enum noside noside, const char *name);
  67 extern struct value *eval_op_ternop (struct type *expect_type,
  68                                      struct expression *exp,
  69                                      enum noside noside,
  70                                      struct value *array, struct value *low,
  71                                      struct value *upper);
  72 extern struct value *eval_op_structop_struct (struct type *expect_type,
  73                                               struct expression *exp,
  74                                               enum noside noside,
  75                                               struct value *arg1,
  76                                               const char *string);
  77 extern struct value *eval_op_structop_ptr (struct type *expect_type,
  78                                            struct expression *exp,
  79                                            enum noside noside,
  80                                            struct value *arg1,
  81                                            const char *string);
  82 extern struct value *eval_op_member (struct type *expect_type,
  83                                      struct expression *exp,
  84                                      enum noside noside,
  85                                      struct value *arg1, struct value *arg2);
  86 extern struct value *eval_op_add (struct type *expect_type,
  87                                   struct expression *exp,
  88                                   enum noside noside,
  89                                   struct value *arg1, struct value *arg2);
  90 extern struct value *eval_op_sub (struct type *expect_type,
  91                                   struct expression *exp,
  92                                   enum noside noside,
  93                                   struct value *arg1, struct value *arg2);
  94 extern struct value *eval_op_binary (struct type *expect_type,
  95                                      struct expression *exp,
  96                                      enum noside noside, enum exp_opcode op,
  97                                      struct value *arg1, struct value *arg2);
  98 extern struct value *eval_op_subscript (struct type *expect_type,
  99                                         struct expression *exp,
 100                                         enum noside noside, enum exp_opcode op,
 101                                         struct value *arg1,
 102                                         struct value *arg2);
 103 extern struct value *eval_op_equal (struct type *expect_type,
 104                                     struct expression *exp,
 105                                     enum noside noside, enum exp_opcode op,
 106                                     struct value *arg1,
 107                                     struct value *arg2);
 108 extern struct value *eval_op_notequal (struct type *expect_type,
 109                                        struct expression *exp,
 110                                        enum noside noside, enum exp_opcode op,
 111                                        struct value *arg1,
 112                                        struct value *arg2);
 113 extern struct value *eval_op_less (struct type *expect_type,
 114                                    struct expression *exp,
 115                                    enum noside noside, enum exp_opcode op,
 116                                    struct value *arg1,
 117                                    struct value *arg2);
 118 extern struct value *eval_op_gtr (struct type *expect_type,
 119                                   struct expression *exp,
 120                                   enum noside noside, enum exp_opcode op,
 121                                   struct value *arg1,
 122                                   struct value *arg2);
 123 extern struct value *eval_op_geq (struct type *expect_type,
 124                                   struct expression *exp,
 125                                   enum noside noside, enum exp_opcode op,
 126                                   struct value *arg1,
 127                                   struct value *arg2);
 128 extern struct value *eval_op_leq (struct type *expect_type,
 129                                   struct expression *exp,
 130                                   enum noside noside, enum exp_opcode op,
 131                                   struct value *arg1,
 132                                   struct value *arg2);
 133 extern struct value *eval_op_repeat (struct type *expect_type,
 134                                      struct expression *exp,
 135                                      enum noside noside, enum exp_opcode op,
 136                                      struct value *arg1,
 137                                      struct value *arg2);
 138 extern struct value *eval_op_plus (struct type *expect_type,
 139                                    struct expression *exp,
 140                                    enum noside noside, enum exp_opcode op,
 141                                    struct value *arg1);
 142 extern struct value *eval_op_neg (struct type *expect_type,
 143                                   struct expression *exp,
 144                                   enum noside noside, enum exp_opcode op,
 145                                   struct value *arg1);
 146 extern struct value *eval_op_complement (struct type *expect_type,
 147                                          struct expression *exp,
 148                                          enum noside noside,
 149                                          enum exp_opcode op,
 150                                          struct value *arg1);
 151 extern struct value *eval_op_lognot (struct type *expect_type,
 152                                      struct expression *exp,
 153                                      enum noside noside,
 154                                      enum exp_opcode op,
 155                                      struct value *arg1);
 156 extern struct value *eval_op_preinc (struct type *expect_type,
 157                                      struct expression *exp,
 158                                      enum noside noside,
 159                                      enum exp_opcode op,
 160                                      struct value *arg1);
 161 extern struct value *eval_op_predec (struct type *expect_type,
 162                                      struct expression *exp,
 163                                      enum noside noside,
 164                                      enum exp_opcode op,
 165                                      struct value *arg1);
 166 extern struct value *eval_op_postinc (struct type *expect_type,
 167                                       struct expression *exp,
 168                                       enum noside noside,
 169                                       enum exp_opcode op,
 170                                       struct value *arg1);
 171 extern struct value *eval_op_postdec (struct type *expect_type,
 172                                       struct expression *exp,
 173                                       enum noside noside,
 174                                       enum exp_opcode op,
 175                                       struct value *arg1);
 176 extern struct value *eval_op_ind (struct type *expect_type,
 177                                   struct expression *exp,
 178                                   enum noside noside,
 179                                   struct value *arg1);
 180 extern struct value *eval_op_type (struct type *expect_type,
 181                                    struct expression *exp,
 182                                    enum noside noside, struct type *type);
 183 extern struct value *eval_op_alignof (struct type *expect_type,
 184                                       struct expression *exp,
 185                                       enum noside noside,
 186                                       struct value *arg1);
 187 extern struct value *eval_op_memval (struct type *expect_type,
 188                                      struct expression *exp,
 189                                      enum noside noside,
 190                                      struct value *arg1, struct type *type);
 191 extern struct value *eval_binop_assign_modify (struct type *expect_type,
 192                                                struct expression *exp,
 193                                                enum noside noside,
 194                                                enum exp_opcode op,
 195                                                struct value *arg1,
 196                                                struct value *arg2);
 197
 198 namespace expr
 199 {
 200
 201 class ada_component;
 202
 203 /* The check_objfile overloads are used to check whether a particular
 204    component of some operation references an objfile.  The passed-in
 205    objfile will never be a debug objfile.  */
 206
 207 /* See if EXP_OBJFILE matches OBJFILE.  */
 208 static inline bool
 209 check_objfile (struct objfile *exp_objfile, struct objfile *objfile)
 210 {
 211   if (exp_objfile->separate_debug_objfile_backlink)
 212     exp_objfile = exp_objfile->separate_debug_objfile_backlink;
 213   return exp_objfile == objfile;
 214 }
 215
 216 static inline bool
 217 check_objfile (struct type *type, struct objfile *objfile)
 218 {
 219   struct objfile *ty_objfile = type->objfile_owner ();
 220   if (ty_objfile != nullptr)
 221     return check_objfile (ty_objfile, objfile);
 222   return false;
 223 }
 224
 225 static inline bool
 226 check_objfile (struct symbol *sym, struct objfile *objfile)
 227 {
 228   return check_objfile (sym->objfile (), objfile);
 229 }
 230
 231 static inline bool
 232 check_objfile (const struct block *block, struct objfile *objfile)
 233 {
 234   return check_objfile (block_objfile (block), objfile);
 235 }
 236
 237 static inline bool
 238 check_objfile (const block_symbol &sym, struct objfile *objfile)
 239 {
 240   return (check_objfile (sym.symbol, objfile)
 241           || check_objfile (sym.block, objfile));
 242 }
 243
 244 static inline bool
 245 check_objfile (bound_minimal_symbol minsym, struct objfile *objfile)
 246 {
 247   return check_objfile (minsym.objfile, objfile);
 248 }
 249
 250 static inline bool
 251 check_objfile (internalvar *ivar, struct objfile *objfile)
 252 {
 253   return false;
 254 }
 255
 256 static inline bool
 257 check_objfile (const std::string &str, struct objfile *objfile)
 258 {
 259   return false;
 260 }
 261
 262 static inline bool
 263 check_objfile (const operation_up &op, struct objfile *objfile)
 264 {
 265   return op->uses_objfile (objfile);
 266 }
 267
 268 static inline bool
 269 check_objfile (enum exp_opcode val, struct objfile *objfile)
 270 {
 271   return false;
 272 }
 273
 274 static inline bool
 275 check_objfile (ULONGEST val, struct objfile *objfile)
 276 {
 277   return false;
 278 }
 279
 280 template<typename T>
 281 static inline bool
 282 check_objfile (enum_flags<T> val, struct objfile *objfile)
 283 {
 284   return false;
 285 }
 286
 287 template<typename T>
 288 static inline bool
 289 check_objfile (const std::vector<T> &collection, struct objfile *objfile)
 290 {
 291   for (const auto &item : collection)
 292     {
 293       if (check_objfile (item, objfile))
 294         return true;
 295     }
 296   return false;
 297 }
 298
 299 template<typename S, typename T>
 300 static inline bool
 301 check_objfile (const std::pair<S, T> &item, struct objfile *objfile)
 302 {
 303   return (check_objfile (item.first, objfile)
 304           || check_objfile (item.second, objfile));
 305 }
 306
 307 extern bool check_objfile (const std::unique_ptr<ada_component> &comp,
 308                            struct objfile *objfile);
 309
 310 static inline void
 311 dump_for_expression (struct ui_file *stream, int depth,
 312                      const operation_up &op)
 313 {
 314   op->dump (stream, depth);
 315 }
 316
 317 extern void dump_for_expression (struct ui_file *stream, int depth,
 318                                  enum exp_opcode op);
 319 extern void dump_for_expression (struct ui_file *stream, int depth,
 320                                  const std::string &str);
 321 extern void dump_for_expression (struct ui_file *stream, int depth,
 322                                  struct type *type);
 323 extern void dump_for_expression (struct ui_file *stream, int depth,
 324                                  CORE_ADDR addr);
 325 extern void dump_for_expression (struct ui_file *stream, int depth,
 326                                  internalvar *ivar);
 327 extern void dump_for_expression (struct ui_file *stream, int depth,
 328                                  symbol *sym);
 329 extern void dump_for_expression (struct ui_file *stream, int depth,
 330                                  const block_symbol &sym);
 331 extern void dump_for_expression (struct ui_file *stream, int depth,
 332                                  bound_minimal_symbol msym);
 333 extern void dump_for_expression (struct ui_file *stream, int depth,
 334                                  const block *bl);
 335 extern void dump_for_expression (struct ui_file *stream, int depth,
 336                                  type_instance_flags flags);
 337 extern void dump_for_expression (struct ui_file *stream, int depth,
 338                                  enum c_string_type_values flags);
 339 extern void dump_for_expression (struct ui_file *stream, int depth,
 340                                  enum range_flag flags);
 341 extern void dump_for_expression (struct ui_file *stream, int depth,
 342                                  const std::unique_ptr<ada_component> &comp);
 343
 344 template<typename T>
 345 void
 346 dump_for_expression (struct ui_file *stream, int depth,
 347                      const std::vector<T> &vals)
 348 {
 349   gdb_printf (stream, _("%*sVector:\n"), depth, "");
 350   for (auto &item : vals)
 351     dump_for_expression (stream, depth + 1, item);
 352 }
 353
 354 template<typename X, typename Y>
 355 void
 356 dump_for_expression (struct ui_file *stream, int depth,
 357                      const std::pair<X, Y> &vals)
 358 {
 359   dump_for_expression (stream, depth, vals.first);
 360   dump_for_expression (stream, depth, vals.second);
 361 }
 362
 363 /* Base class for most concrete operations.  This class holds data,
 364    specified via template parameters, and supplies generic
 365    implementations of the 'dump' and 'uses_objfile' methods.  */
 366 template<typename... Arg>
 367 class tuple_holding_operation : public operation
 368 {
 369 public:
 370
 371   explicit tuple_holding_operation (Arg... args)
 372     : m_storage (std::forward<Arg> (args)...)
 373   {
 374   }
 375
 376   DISABLE_COPY_AND_ASSIGN (tuple_holding_operation);
 377
 378   bool uses_objfile (struct objfile *objfile) const override
 379   {
 380     return do_check_objfile<0, Arg...> (objfile, m_storage);
 381   }
 382
 383   void dump (struct ui_file *stream, int depth) const override
 384   {
 385     dump_for_expression (stream, depth, opcode ());
 386     do_dump<0, Arg...> (stream, depth + 1, m_storage);
 387   }
 388
 389 protected:
 390
 391   /* Storage for the data.  */
 392   std::tuple<Arg...> m_storage;
 393
 394 private:
 395
 396   /* do_dump does the work of dumping the data.  */
 397   template<int I, typename... T>
 398   typename std::enable_if<I == sizeof... (T), void>::type
 399   do_dump (struct ui_file *stream, int depth, const std::tuple<T...> &value)
 400     const
 401   {
 402   }
 403
 404   template<int I, typename... T>
 405   typename std::enable_if<I < sizeof... (T), void>::type
 406   do_dump (struct ui_file *stream, int depth, const std::tuple<T...> &value)
 407     const
 408   {
 409     dump_for_expression (stream, depth, std::get<I> (value));
 410     do_dump<I + 1, T...> (stream, depth, value);
 411   }
 412
 413   /* do_check_objfile does the work of checking whether this object
 414      refers to OBJFILE.  */
 415   template<int I, typename... T>
 416   typename std::enable_if<I == sizeof... (T), bool>::type
 417   do_check_objfile (struct objfile *objfile, const std::tuple<T...> &value)
 418     const
 419   {
 420     return false;
 421   }
 422
 423   template<int I, typename... T>
 424   typename std::enable_if<I < sizeof... (T), bool>::type
 425   do_check_objfile (struct objfile *objfile, const std::tuple<T...> &value)
 426     const
 427   {
 428     if (check_objfile (std::get<I> (value), objfile))
 429       return true;
 430     return do_check_objfile<I + 1, T...> (objfile, value);
 431   }
 432 };
 433
 434 /* The check_constant overloads are used to decide whether a given
 435    concrete operation is a constant.  This is done by checking the
 436    operands.  */
 437
 438 static inline bool
 439 check_constant (const operation_up &item)
 440 {
 441   return item->constant_p ();
 442 }
 443
 444 static inline bool
 445 check_constant (bound_minimal_symbol msym)
 446 {
 447   return false;
 448 }
 449
 450 static inline bool
 451 check_constant (struct type *type)
 452 {
 453   return true;
 454 }
 455
 456 static inline bool
 457 check_constant (const struct block *block)
 458 {
 459   return true;
 460 }
 461
 462 static inline bool
 463 check_constant (const std::string &str)
 464 {
 465   return true;
 466 }
 467
 468 static inline bool
 469 check_constant (ULONGEST cst)
 470 {
 471   return true;
 472 }
 473
 474 static inline bool
 475 check_constant (struct symbol *sym)
 476 {
 477   enum address_class sc = sym->aclass ();
 478   return (sc == LOC_BLOCK
 479           || sc == LOC_CONST
 480           || sc == LOC_CONST_BYTES
 481           || sc == LOC_LABEL);
 482 }
 483
 484 static inline bool
 485 check_constant (const block_symbol &sym)
 486 {
 487   /* We know the block is constant, so we only need to check the
 488      symbol.  */
 489   return check_constant (sym.symbol);
 490 }
 491
 492 template<typename T>
 493 static inline bool
 494 check_constant (const std::vector<T> &collection)
 495 {
 496   for (const auto &item : collection)
 497     if (!check_constant (item))
 498       return false;
 499   return true;
 500 }
 501
 502 template<typename S, typename T>
 503 static inline bool
 504 check_constant (const std::pair<S, T> &item)
 505 {
 506   return check_constant (item.first) && check_constant (item.second);
 507 }
 508
 509 /* Base class for concrete operations.  This class supplies an
 510    implementation of 'constant_p' that works by checking the
 511    operands.  */
 512 template<typename... Arg>
 513 class maybe_constant_operation
 514   : public tuple_holding_operation<Arg...>
 515 {
 516 public:
 517
 518   using tuple_holding_operation<Arg...>::tuple_holding_operation;
 519
 520   bool constant_p () const override
 521   {
 522     return do_check_constant<0, Arg...> (this->m_storage);
 523   }
 524
 525 private:
 526
 527   template<int I, typename... T>
 528   typename std::enable_if<I == sizeof... (T), bool>::type
 529   do_check_constant (const std::tuple<T...> &value) const
 530   {
 531     return true;
 532   }
 533
 534   template<int I, typename... T>
 535   typename std::enable_if<I < sizeof... (T), bool>::type
 536   do_check_constant (const std::tuple<T...> &value) const
 537   {
 538     if (!check_constant (std::get<I> (value)))
 539       return false;
 540     return do_check_constant<I + 1, T...> (value);
 541   }
 542 };
 543
 544 /* A floating-point constant.  The constant is encoded in the target
 545    format.  */
 546
 547 typedef std::array<gdb_byte, 16> float_data;
 548
 549 /* An operation that holds a floating-point constant of a given
 550    type.
 551
 552    This does not need the facilities provided by
 553    tuple_holding_operation, so it does not use it.  */
 554 class float_const_operation
 555   : public operation
 556 {
 557 public:
 558
 559   float_const_operation (struct type *type, float_data data)
 560     : m_type (type),
 561       m_data (data)
 562   {
 563   }
 564
 565   value *evaluate (struct type *expect_type,
 566                    struct expression *exp,
 567                    enum noside noside) override
 568   {
 569     return value_from_contents (m_type, m_data.data ());
 570   }
 571
 572   enum exp_opcode opcode () const override
 573   { return OP_FLOAT; }
 574
 575   bool constant_p () const override
 576   { return true; }
 577
 578   void dump (struct ui_file *stream, int depth) const override;
 579
 580 private:
 581
 582   struct type *m_type;
 583   float_data m_data;
 584 };
 585
 586 class scope_operation
 587   : public maybe_constant_operation<struct type *, std::string>
 588 {
 589 public:
 590
 591   using maybe_constant_operation::maybe_constant_operation;
 592
 593   value *evaluate (struct type *expect_type,
 594                    struct expression *exp,
 595                    enum noside noside) override
 596   {
 597     return eval_op_scope (expect_type, exp, noside,
 598                           std::get<0> (m_storage),
 599                           std::get<1> (m_storage).c_str ());
 600   }
 601
 602   value *evaluate_for_address (struct expression *exp,
 603                                enum noside noside) override;
 604
 605   value *evaluate_funcall (struct type *expect_type,
 606                            struct expression *exp,
 607                            enum noside noside,
 608                            const std::vector<operation_up> &args) override;
 609
 610   enum exp_opcode opcode () const override
 611   { return OP_SCOPE; }
 612
 613 protected:
 614
 615   void do_generate_ax (struct expression *exp,
 616                        struct agent_expr *ax,
 617                        struct axs_value *value,
 618                        struct type *cast_type)
 619     override;
 620 };
 621
 622 /* Compute the value of a variable.  */
 623 class var_value_operation
 624   : public maybe_constant_operation<block_symbol>
 625 {
 626 public:
 627
 628   using maybe_constant_operation::maybe_constant_operation;
 629
 630   value *evaluate (struct type *expect_type,
 631                    struct expression *exp,
 632                    enum noside noside) override;
 633
 634   value *evaluate_with_coercion (struct expression *exp,
 635                                  enum noside noside) override;
 636
 637   value *evaluate_for_sizeof (struct expression *exp, enum noside noside)
 638     override;
 639
 640   value *evaluate_for_cast (struct type *expect_type,
 641                             struct expression *exp,
 642                             enum noside noside) override;
 643
 644   value *evaluate_for_address (struct expression *exp, enum noside noside)
 645     override;
 646
 647   value *evaluate_funcall (struct type *expect_type,
 648                            struct expression *exp,
 649                            enum noside noside,
 650                            const std::vector<operation_up> &args) override;
 651
 652   enum exp_opcode opcode () const override
 653   { return OP_VAR_VALUE; }
 654
 655   /* Return the symbol referenced by this object.  */
 656   symbol *get_symbol () const
 657   {
 658     return std::get<0> (m_storage).symbol;
 659   }
 660
 661 protected:
 662
 663   void do_generate_ax (struct expression *exp,
 664                        struct agent_expr *ax,
 665                        struct axs_value *value,
 666                        struct type *cast_type)
 667     override;
 668 };
 669
 670 class long_const_operation
 671   : public tuple_holding_operation<struct type *, LONGEST>
 672 {
 673 public:
 674
 675   using tuple_holding_operation::tuple_holding_operation;
 676
 677   value *evaluate (struct type *expect_type,
 678                    struct expression *exp,
 679                    enum noside noside) override
 680   {
 681     return value_from_longest (std::get<0> (m_storage),
 682                                std::get<1> (m_storage));
 683   }
 684
 685   enum exp_opcode opcode () const override
 686   { return OP_LONG; }
 687
 688   bool constant_p () const override
 689   { return true; }
 690
 691 protected:
 692
 693   void do_generate_ax (struct expression *exp,
 694                        struct agent_expr *ax,
 695                        struct axs_value *value,
 696                        struct type *cast_type)
 697     override;
 698 };
 699
 700 class var_msym_value_operation
 701   : public maybe_constant_operation<bound_minimal_symbol>
 702 {
 703 public:
 704
 705   using maybe_constant_operation::maybe_constant_operation;
 706
 707   value *evaluate (struct type *expect_type,
 708                    struct expression *exp,
 709                    enum noside noside) override
 710   {
 711     return eval_op_var_msym_value (expect_type, exp, noside, m_outermost,
 712                                    std::get<0> (m_storage));
 713   }
 714
 715   value *evaluate_for_sizeof (struct expression *exp, enum noside noside)
 716     override;
 717
 718   value *evaluate_for_address (struct expression *exp, enum noside noside)
 719     override;
 720
 721   value *evaluate_for_cast (struct type *expect_type,
 722                             struct expression *exp,
 723                             enum noside noside) override;
 724
 725   value *evaluate_funcall (struct type *expect_type,
 726                            struct expression *exp,
 727                            enum noside noside,
 728                            const std::vector<operation_up> &args) override
 729   {
 730     const char *name = std::get<0> (m_storage).minsym->print_name ();
 731     return operation::evaluate_funcall (expect_type, exp, noside, name, args);
 732   }
 733
 734   enum exp_opcode opcode () const override
 735   { return OP_VAR_MSYM_VALUE; }
 736
 737   void set_outermost () override
 738   {
 739     m_outermost = true;
 740   }
 741
 742 protected:
 743
 744   /* True if this is the outermost operation in the expression.  */
 745   bool m_outermost = false;
 746
 747   void do_generate_ax (struct expression *exp,
 748                        struct agent_expr *ax,
 749                        struct axs_value *value,
 750                        struct type *cast_type)
 751     override;
 752 };
 753
 754 class var_entry_value_operation
 755   : public tuple_holding_operation<symbol *>
 756 {
 757 public:
 758
 759   using tuple_holding_operation::tuple_holding_operation;
 760
 761   value *evaluate (struct type *expect_type,
 762                    struct expression *exp,
 763                    enum noside noside) override
 764   {
 765     return eval_op_var_entry_value (expect_type, exp, noside,
 766                                     std::get<0> (m_storage));
 767   }
 768
 769   enum exp_opcode opcode () const override
 770   { return OP_VAR_ENTRY_VALUE; }
 771 };
 772
 773 class func_static_var_operation
 774   : public maybe_constant_operation<operation_up, std::string>
 775 {
 776 public:
 777
 778   using maybe_constant_operation::maybe_constant_operation;
 779
 780   value *evaluate (struct type *expect_type,
 781                    struct expression *exp,
 782                    enum noside noside) override
 783   {
 784     value *func = std::get<0> (m_storage)->evaluate (nullptr, exp, noside);
 785     return eval_op_func_static_var (expect_type, exp, noside, func,
 786                                     std::get<1> (m_storage).c_str ());
 787   }
 788
 789   enum exp_opcode opcode () const override
 790   { return OP_FUNC_STATIC_VAR; }
 791 };
 792
 793 class last_operation
 794   : public tuple_holding_operation<int>
 795 {
 796 public:
 797
 798   using tuple_holding_operation::tuple_holding_operation;
 799
 800   value *evaluate (struct type *expect_type,
 801                    struct expression *exp,
 802                    enum noside noside) override
 803   {
 804     return access_value_history (std::get<0> (m_storage));
 805   }
 806
 807   enum exp_opcode opcode () const override
 808   { return OP_LAST; }
 809 };
 810
 811 class register_operation
 812   : public tuple_holding_operation<std::string>
 813 {
 814 public:
 815
 816   using tuple_holding_operation::tuple_holding_operation;
 817
 818   value *evaluate (struct type *expect_type,
 819                    struct expression *exp,
 820                    enum noside noside) override
 821   {
 822     return eval_op_register (expect_type, exp, noside,
 823                              std::get<0> (m_storage).c_str ());
 824   }
 825
 826   enum exp_opcode opcode () const override
 827   { return OP_REGISTER; }
 828
 829   /* Return the name of the register.  */
 830   const char *get_name () const
 831   {
 832     return std::get<0> (m_storage).c_str ();
 833   }
 834
 835 protected:
 836
 837   void do_generate_ax (struct expression *exp,
 838                        struct agent_expr *ax,
 839                        struct axs_value *value,
 840                        struct type *cast_type)
 841     override;
 842 };
 843
 844 class bool_operation
 845   : public tuple_holding_operation<bool>
 846 {
 847 public:
 848
 849   using tuple_holding_operation::tuple_holding_operation;
 850
 851   value *evaluate (struct type *expect_type,
 852                    struct expression *exp,
 853                    enum noside noside) override
 854   {
 855     struct type *type = language_bool_type (exp->language_defn, exp->gdbarch);
 856     return value_from_longest (type, std::get<0> (m_storage));
 857   }
 858
 859   enum exp_opcode opcode () const override
 860   { return OP_BOOL; }
 861
 862   bool constant_p () const override
 863   { return true; }
 864 };
 865
 866 class internalvar_operation
 867   : public tuple_holding_operation<internalvar *>
 868 {
 869 public:
 870
 871   using tuple_holding_operation::tuple_holding_operation;
 872
 873   value *evaluate (struct type *expect_type,
 874                    struct expression *exp,
 875                    enum noside noside) override
 876   {
 877     return value_of_internalvar (exp->gdbarch,
 878                                  std::get<0> (m_storage));
 879   }
 880
 881   internalvar *get_internalvar () const
 882   {
 883     return std::get<0> (m_storage);
 884   }
 885
 886   enum exp_opcode opcode () const override
 887   { return OP_INTERNALVAR; }
 888
 889 protected:
 890
 891   void do_generate_ax (struct expression *exp,
 892                        struct agent_expr *ax,
 893                        struct axs_value *value,
 894                        struct type *cast_type)
 895     override;
 896 };
 897
 898 class string_operation
 899   : public tuple_holding_operation<std::string>
 900 {
 901 public:
 902
 903   using tuple_holding_operation::tuple_holding_operation;
 904
 905   value *evaluate (struct type *expect_type,
 906                    struct expression *exp,
 907                    enum noside noside) override;
 908
 909   enum exp_opcode opcode () const override
 910   { return OP_STRING; }
 911 };
 912
 913 class ternop_slice_operation
 914   : public maybe_constant_operation<operation_up, operation_up, operation_up>
 915 {
 916 public:
 917
 918   using maybe_constant_operation::maybe_constant_operation;
 919
 920   value *evaluate (struct type *expect_type,
 921                    struct expression *exp,
 922                    enum noside noside) override
 923   {
 924     struct value *array
 925       = std::get<0> (m_storage)->evaluate (nullptr, exp, noside);
 926     struct value *low
 927       = std::get<1> (m_storage)->evaluate (nullptr, exp, noside);
 928     struct value *upper
 929       = std::get<2> (m_storage)->evaluate (nullptr, exp, noside);
 930     return eval_op_ternop (expect_type, exp, noside, array, low, upper);
 931   }
 932
 933   enum exp_opcode opcode () const override
 934   { return TERNOP_SLICE; }
 935 };
 936
 937 class ternop_cond_operation
 938   : public maybe_constant_operation<operation_up, operation_up, operation_up>
 939 {
 940 public:
 941
 942   using maybe_constant_operation::maybe_constant_operation;
 943
 944   value *evaluate (struct type *expect_type,
 945                    struct expression *exp,
 946                    enum noside noside) override
 947   {
 948     struct value *val
 949       = std::get<0> (m_storage)->evaluate (nullptr, exp, noside);
 950
 951     if (value_logical_not (val))
 952       return std::get<2> (m_storage)->evaluate (nullptr, exp, noside);
 953     return std::get<1> (m_storage)->evaluate (nullptr, exp, noside);
 954   }
 955
 956   enum exp_opcode opcode () const override
 957   { return TERNOP_COND; }
 958
 959 protected:
 960
 961   void do_generate_ax (struct expression *exp,
 962                        struct agent_expr *ax,
 963                        struct axs_value *value,
 964                        struct type *cast_type)
 965     override;
 966 };
 967
 968 class complex_operation
 969   : public maybe_constant_operation<operation_up, operation_up, struct type *>
 970 {
 971 public:
 972
 973   using maybe_constant_operation::maybe_constant_operation;
 974
 975   value *evaluate (struct type *expect_type,
 976                    struct expression *exp,
 977                    enum noside noside) override
 978   {
 979     value *real = std::get<0> (m_storage)->evaluate (nullptr, exp, noside);
 980     value *imag = std::get<1> (m_storage)->evaluate (nullptr, exp, noside);
 981     return value_literal_complex (real, imag,
 982                                   std::get<2> (m_storage));
 983   }
 984
 985   enum exp_opcode opcode () const override
 986   { return OP_COMPLEX; }
 987 };
 988
 989 class structop_base_operation
 990   : public tuple_holding_operation<operation_up, std::string>
 991 {
 992 public:
 993
 994   /* Used for completion.  Return the field name.  */
 995   const std::string &get_string () const
 996   {
 997     return std::get<1> (m_storage);
 998   }
 999
1000   value *evaluate_funcall (struct type *expect_type,
1001                            struct expression *exp,
1002                            enum noside noside,
1003                            const std::vector<operation_up> &args) override;
1004
1005   /* Try to complete this operation in the context of EXP.  TRACKER is
1006      the completion tracker to update.  Return true if completion was
1007      possible, false otherwise.  */
1008   virtual bool complete (struct expression *exp, completion_tracker &tracker)
1009   {
1010     return complete (exp, tracker, "");
1011   }
1012
1013 protected:
1014
1015   /* Do the work of the public 'complete' method.  PREFIX is prepended
1016      to each result.  */
1017   bool complete (struct expression *exp, completion_tracker &tracker,
1018                  const char *prefix);
1019
1020   using tuple_holding_operation::tuple_holding_operation;
1021 };
1022
1023 class structop_operation
1024   : public structop_base_operation
1025 {
1026 public:
1027
1028   using structop_base_operation::structop_base_operation;
1029
1030   value *evaluate (struct type *expect_type,
1031                    struct expression *exp,
1032                    enum noside noside) override
1033   {
1034     value *val =std::get<0> (m_storage)->evaluate (nullptr, exp, noside);
1035     return eval_op_structop_struct (expect_type, exp, noside, val,
1036                                     std::get<1> (m_storage).c_str ());
1037   }
1038
1039   enum exp_opcode opcode () const override
1040   { return STRUCTOP_STRUCT; }
1041
1042 protected:
1043
1044   void do_generate_ax (struct expression *exp,
1045                        struct agent_expr *ax,
1046                        struct axs_value *value,
1047                        struct type *cast_type)
1048     override
1049   {
1050     gen_expr_structop (exp, STRUCTOP_STRUCT,
1051                        std::get<0> (this->m_storage).get (),
1052                        std::get<1> (this->m_storage).c_str (),
1053                        ax, value);
1054   }
1055 };
1056
1057 class structop_ptr_operation
1058   : public structop_base_operation
1059 {
1060 public:
1061
1062   using structop_base_operation::structop_base_operation;
1063
1064   value *evaluate (struct type *expect_type,
1065                    struct expression *exp,
1066                    enum noside noside) override
1067   {
1068     value *val = std::get<0> (m_storage)->evaluate (nullptr, exp, noside);
1069     return eval_op_structop_ptr (expect_type, exp, noside, val,
1070                                  std::get<1> (m_storage).c_str ());
1071   }
1072
1073   enum exp_opcode opcode () const override
1074   { return STRUCTOP_PTR; }
1075
1076 protected:
1077
1078   void do_generate_ax (struct expression *exp,
1079                        struct agent_expr *ax,
1080                        struct axs_value *value,
1081                        struct type *cast_type)
1082     override
1083   {
1084     gen_expr_structop (exp, STRUCTOP_PTR,
1085                        std::get<0> (this->m_storage).get (),
1086                        std::get<1> (this->m_storage).c_str (),
1087                        ax, value);
1088   }
1089 };
1090
1091 class structop_member_base
1092   : public tuple_holding_operation<operation_up, operation_up>
1093 {
1094 public:
1095
1096   using tuple_holding_operation::tuple_holding_operation;
1097
1098   value *evaluate_funcall (struct type *expect_type,
1099                            struct expression *exp,
1100                            enum noside noside,
1101                            const std::vector<operation_up> &args) override;
1102 };
1103
1104 class structop_member_operation
1105   : public structop_member_base
1106 {
1107 public:
1108
1109   using structop_member_base::structop_member_base;
1110
1111   value *evaluate (struct type *expect_type,
1112                    struct expression *exp,
1113                    enum noside noside) override
1114   {
1115     value *lhs
1116       = std::get<0> (m_storage)->evaluate_for_address (exp, noside);
1117     value *rhs
1118       = std::get<1> (m_storage)->evaluate (nullptr, exp, noside);
1119     return eval_op_member (expect_type, exp, noside, lhs, rhs);
1120   }
1121
1122   enum exp_opcode opcode () const override
1123   { return STRUCTOP_MEMBER; }
1124 };
1125
1126 class structop_mptr_operation
1127   : public structop_member_base
1128 {
1129 public:
1130
1131   using structop_member_base::structop_member_base;
1132
1133   value *evaluate (struct type *expect_type,
1134                    struct expression *exp,
1135                    enum noside noside) override
1136   {
1137     value *lhs
1138       = std::get<0> (m_storage)->evaluate (nullptr, exp, noside);
1139     value *rhs
1140       = std::get<1> (m_storage)->evaluate (nullptr, exp, noside);
1141     return eval_op_member (expect_type, exp, noside, lhs, rhs);
1142   }
1143
1144   enum exp_opcode opcode () const override
1145   { return STRUCTOP_MPTR; }
1146 };
1147
1148 class concat_operation
1149   : public maybe_constant_operation<operation_up, operation_up>
1150 {
1151 public:
1152
1153   using maybe_constant_operation::maybe_constant_operation;
1154
1155   value *evaluate (struct type *expect_type,
1156                    struct expression *exp,
1157                    enum noside noside) override
1158   {
1159     value *lhs
1160       = std::get<0> (m_storage)->evaluate_with_coercion (exp, noside);
1161     value *rhs
1162       = std::get<1> (m_storage)->evaluate_with_coercion (exp, noside);
1163     return value_concat (lhs, rhs);
1164   }
1165
1166   enum exp_opcode opcode () const override
1167   { return BINOP_CONCAT; }
1168 };
1169
1170 class add_operation
1171   : public maybe_constant_operation<operation_up, operation_up>
1172 {
1173 public:
1174
1175   using maybe_constant_operation::maybe_constant_operation;
1176
1177   value *evaluate (struct type *expect_type,
1178                    struct expression *exp,
1179                    enum noside noside) override
1180   {
1181     value *lhs
1182       = std::get<0> (m_storage)->evaluate_with_coercion (exp, noside);
1183     value *rhs
1184       = std::get<1> (m_storage)->evaluate_with_coercion (exp, noside);
1185     return eval_op_add (expect_type, exp, noside, lhs, rhs);
1186   }
1187
1188   enum exp_opcode opcode () const override
1189   { return BINOP_ADD; }
1190
1191 protected:
1192
1193   void do_generate_ax (struct expression *exp,
1194                        struct agent_expr *ax,
1195                        struct axs_value *value,
1196                        struct type *cast_type)
1197     override
1198   {
1199     gen_expr_binop (exp, BINOP_ADD,
1200                     std::get<0> (this->m_storage).get (),
1201                     std::get<1> (this->m_storage).get (),
1202                     ax, value);
1203   }
1204 };
1205
1206 class sub_operation
1207   : public maybe_constant_operation<operation_up, operation_up>
1208 {
1209 public:
1210
1211   using maybe_constant_operation::maybe_constant_operation;
1212
1213   value *evaluate (struct type *expect_type,
1214                    struct expression *exp,
1215                    enum noside noside) override
1216   {
1217     value *lhs
1218       = std::get<0> (m_storage)->evaluate_with_coercion (exp, noside);
1219     value *rhs
1220       = std::get<1> (m_storage)->evaluate_with_coercion (exp, noside);
1221     return eval_op_sub (expect_type, exp, noside, lhs, rhs);
1222   }
1223
1224   enum exp_opcode opcode () const override
1225   { return BINOP_SUB; }
1226
1227 protected:
1228
1229   void do_generate_ax (struct expression *exp,
1230                        struct agent_expr *ax,
1231                        struct axs_value *value,
1232                        struct type *cast_type)
1233     override
1234   {
1235     gen_expr_binop (exp, BINOP_SUB,
1236                     std::get<0> (this->m_storage).get (),
1237                     std::get<1> (this->m_storage).get (),
1238                     ax, value);
1239   }
1240 };
1241
1242 typedef struct value *binary_ftype (struct type *expect_type,
1243                                     struct expression *exp,
1244                                     enum noside noside, enum exp_opcode op,
1245                                     struct value *arg1, struct value *arg2);
1246
1247 template<enum exp_opcode OP, binary_ftype FUNC>
1248 class binop_operation
1249   : public maybe_constant_operation<operation_up, operation_up>
1250 {
1251 public:
1252
1253   using maybe_constant_operation::maybe_constant_operation;
1254
1255   value *evaluate (struct type *expect_type,
1256                    struct expression *exp,
1257                    enum noside noside) override
1258   {
1259     value *lhs
1260       = std::get<0> (m_storage)->evaluate (nullptr, exp, noside);
1261     value *rhs
1262       = std::get<1> (m_storage)->evaluate (nullptr, exp, noside);
1263     return FUNC (expect_type, exp, noside, OP, lhs, rhs);
1264   }
1265
1266   enum exp_opcode opcode () const override
1267   { return OP; }
1268 };
1269
1270 template<enum exp_opcode OP, binary_ftype FUNC>
1271 class usual_ax_binop_operation
1272   : public binop_operation<OP, FUNC>
1273 {
1274 public:
1275
1276   using binop_operation<OP, FUNC>::binop_operation;
1277
1278 protected:
1279
1280   void do_generate_ax (struct expression *exp,
1281                        struct agent_expr *ax,
1282                        struct axs_value *value,
1283                        struct type *cast_type)
1284     override
1285   {
1286     gen_expr_binop (exp, OP,
1287                     std::get<0> (this->m_storage).get (),
1288                     std::get<1> (this->m_storage).get (),
1289                     ax, value);
1290   }
1291 };
1292
1293 using exp_operation = binop_operation<BINOP_EXP, eval_op_binary>;
1294 using intdiv_operation = binop_operation<BINOP_INTDIV, eval_op_binary>;
1295 using mod_operation = binop_operation<BINOP_MOD, eval_op_binary>;
1296
1297 using mul_operation = usual_ax_binop_operation<BINOP_MUL, eval_op_binary>;
1298 using div_operation = usual_ax_binop_operation<BINOP_DIV, eval_op_binary>;
1299 using rem_operation = usual_ax_binop_operation<BINOP_REM, eval_op_binary>;
1300 using lsh_operation = usual_ax_binop_operation<BINOP_LSH, eval_op_binary>;
1301 using rsh_operation = usual_ax_binop_operation<BINOP_RSH, eval_op_binary>;
1302 using bitwise_and_operation
1303      = usual_ax_binop_operation<BINOP_BITWISE_AND, eval_op_binary>;
1304 using bitwise_ior_operation
1305      = usual_ax_binop_operation<BINOP_BITWISE_IOR, eval_op_binary>;
1306 using bitwise_xor_operation
1307      = usual_ax_binop_operation<BINOP_BITWISE_XOR, eval_op_binary>;
1308
1309 class subscript_operation
1310   : public usual_ax_binop_operation<BINOP_SUBSCRIPT, eval_op_subscript>
1311 {
1312 public:
1313   using usual_ax_binop_operation<BINOP_SUBSCRIPT,
1314                                  eval_op_subscript>::usual_ax_binop_operation;
1315
1316   value *evaluate_for_sizeof (struct expression *exp,
1317                               enum noside noside) override;
1318 };
1319
1320 /* Implementation of comparison operations.  */
1321 template<enum exp_opcode OP, binary_ftype FUNC>
1322 class comparison_operation
1323   : public usual_ax_binop_operation<OP, FUNC>
1324 {
1325 public:
1326
1327   using usual_ax_binop_operation<OP, FUNC>::usual_ax_binop_operation;
1328
1329   value *evaluate (struct type *expect_type,
1330                    struct expression *exp,
1331                    enum noside noside) override
1332   {
1333     value *lhs
1334       = std::get<0> (this->m_storage)->evaluate (nullptr, exp, noside);
1335     value *rhs
1336       = std::get<1> (this->m_storage)->evaluate (value_type (lhs), exp,
1337                                                  noside);
1338     return FUNC (expect_type, exp, noside, OP, lhs, rhs);
1339   }
1340 };
1341
1342 class equal_operation
1343   : public comparison_operation<BINOP_EQUAL, eval_op_equal>
1344 {
1345 public:
1346
1347   using comparison_operation::comparison_operation;
1348
1349   operation *get_lhs () const
1350   {
1351     return std::get<0> (m_storage).get ();
1352   }
1353
1354   operation *get_rhs () const
1355   {
1356     return std::get<1> (m_storage).get ();
1357   }
1358 };
1359
1360 using notequal_operation
1361      = comparison_operation<BINOP_NOTEQUAL, eval_op_notequal>;
1362 using less_operation = comparison_operation<BINOP_LESS, eval_op_less>;
1363 using gtr_operation = comparison_operation<BINOP_GTR, eval_op_gtr>;
1364 using geq_operation = comparison_operation<BINOP_GEQ, eval_op_geq>;
1365 using leq_operation = comparison_operation<BINOP_LEQ, eval_op_leq>;
1366
1367 /* Implement the GDB '@' repeat operator.  */
1368 class repeat_operation
1369   : public binop_operation<BINOP_REPEAT, eval_op_repeat>
1370 {
1371   using binop_operation<BINOP_REPEAT, eval_op_repeat>::binop_operation;
1372
1373 protected:
1374
1375   void do_generate_ax (struct expression *exp,
1376                        struct agent_expr *ax,
1377                        struct axs_value *value,
1378                        struct type *cast_type)
1379     override;
1380 };
1381
1382 /* C-style comma operator.  */
1383 class comma_operation
1384   : public maybe_constant_operation<operation_up, operation_up>
1385 {
1386 public:
1387
1388   using maybe_constant_operation::maybe_constant_operation;
1389
1390   value *evaluate (struct type *expect_type,
1391                    struct expression *exp,
1392                    enum noside noside) override
1393   {
1394     /* The left-hand-side is only evaluated for side effects, so don't
1395        bother in other modes.  */
1396     if (noside == EVAL_NORMAL)
1397       std::get<0> (m_storage)->evaluate (nullptr, exp, noside);
1398     return std::get<1> (m_storage)->evaluate (nullptr, exp, noside);
1399   }
1400
1401   enum exp_opcode opcode () const override
1402   { return BINOP_COMMA; }
1403
1404 protected:
1405
1406   void do_generate_ax (struct expression *exp,
1407                        struct agent_expr *ax,
1408                        struct axs_value *value,
1409                        struct type *cast_type)
1410     override;
1411 };
1412
1413 typedef struct value *unary_ftype (struct type *expect_type,
1414                                    struct expression *exp,
1415                                    enum noside noside, enum exp_opcode op,
1416                                    struct value *arg1);
1417
1418 /* Base class for unary operations.  */
1419 template<enum exp_opcode OP, unary_ftype FUNC>
1420 class unop_operation
1421   : public maybe_constant_operation<operation_up>
1422 {
1423 public:
1424
1425   using maybe_constant_operation::maybe_constant_operation;
1426
1427   value *evaluate (struct type *expect_type,
1428                    struct expression *exp,
1429                    enum noside noside) override
1430   {
1431     value *val = std::get<0> (m_storage)->evaluate (nullptr, exp, noside);
1432     return FUNC (expect_type, exp, noside, OP, val);
1433   }
1434
1435   enum exp_opcode opcode () const override
1436   { return OP; }
1437 };
1438
1439 /* Unary operations that can also be turned into agent expressions in
1440    the "usual" way.  */
1441 template<enum exp_opcode OP, unary_ftype FUNC>
1442 class usual_ax_unop_operation
1443   : public unop_operation<OP, FUNC>
1444 {
1445   using unop_operation<OP, FUNC>::unop_operation;
1446
1447 protected:
1448
1449   void do_generate_ax (struct expression *exp,
1450                        struct agent_expr *ax,
1451                        struct axs_value *value,
1452                        struct type *cast_type)
1453     override
1454   {
1455     gen_expr_unop (exp, OP,
1456                    std::get<0> (this->m_storage).get (),
1457                    ax, value);
1458   }
1459 };
1460
1461 using unary_plus_operation = usual_ax_unop_operation<UNOP_PLUS, eval_op_plus>;
1462 using unary_neg_operation = usual_ax_unop_operation<UNOP_NEG, eval_op_neg>;
1463 using unary_complement_operation
1464      = usual_ax_unop_operation<UNOP_COMPLEMENT, eval_op_complement>;
1465 using unary_logical_not_operation
1466      = usual_ax_unop_operation<UNOP_LOGICAL_NOT, eval_op_lognot>;
1467
1468 /* Handle pre- and post- increment and -decrement.  */
1469 template<enum exp_opcode OP, unary_ftype FUNC>
1470 class unop_incr_operation
1471   : public tuple_holding_operation<operation_up>
1472 {
1473 public:
1474
1475   using tuple_holding_operation::tuple_holding_operation;
1476
1477   value *evaluate (struct type *expect_type,
1478                    struct expression *exp,
1479                    enum noside noside) override
1480   {
1481     value *val = std::get<0> (m_storage)->evaluate (expect_type, exp, noside);
1482     return FUNC (expect_type, exp, noside, OP, val);
1483   }
1484
1485   enum exp_opcode opcode () const override
1486   { return OP; }
1487 };
1488
1489 using preinc_operation
1490      = unop_incr_operation<UNOP_PREINCREMENT, eval_op_preinc>;
1491 using predec_operation
1492      = unop_incr_operation<UNOP_PREDECREMENT, eval_op_predec>;
1493 using postinc_operation
1494      = unop_incr_operation<UNOP_POSTINCREMENT, eval_op_postinc>;
1495 using postdec_operation
1496      = unop_incr_operation<UNOP_POSTDECREMENT, eval_op_postdec>;
1497
1498 /* Base class for implementations of UNOP_IND.  */
1499 class unop_ind_base_operation
1500   : public tuple_holding_operation<operation_up>
1501 {
1502 public:
1503
1504   using tuple_holding_operation::tuple_holding_operation;
1505
1506   value *evaluate (struct type *expect_type,
1507                    struct expression *exp,
1508                    enum noside noside) override
1509   {
1510     if (expect_type != nullptr && expect_type->code () == TYPE_CODE_PTR)
1511       expect_type = TYPE_TARGET_TYPE (check_typedef (expect_type));
1512     value *val = std::get<0> (m_storage)->evaluate (expect_type, exp, noside);
1513     return eval_op_ind (expect_type, exp, noside, val);
1514   }
1515
1516   value *evaluate_for_address (struct expression *exp,
1517                                enum noside noside) override;
1518
1519   value *evaluate_for_sizeof (struct expression *exp,
1520                               enum noside noside) override;
1521
1522   enum exp_opcode opcode () const override
1523   { return UNOP_IND; }
1524 };
1525
1526 /* Ordinary UNOP_IND implementation.  */
1527 class unop_ind_operation
1528   : public unop_ind_base_operation
1529 {
1530 public:
1531
1532   using unop_ind_base_operation::unop_ind_base_operation;
1533
1534 protected:
1535
1536   void do_generate_ax (struct expression *exp,
1537                        struct agent_expr *ax,
1538                        struct axs_value *value,
1539                        struct type *cast_type)
1540     override
1541   {
1542     gen_expr_unop (exp, UNOP_IND,
1543                    std::get<0> (this->m_storage).get (),
1544                    ax, value);
1545   }
1546 };
1547
1548 /* Implement OP_TYPE.  */
1549 class type_operation
1550   : public tuple_holding_operation<struct type *>
1551 {
1552 public:
1553
1554   using tuple_holding_operation::tuple_holding_operation;
1555
1556   value *evaluate (struct type *expect_type,
1557                    struct expression *exp,
1558                    enum noside noside) override
1559   {
1560     return eval_op_type (expect_type, exp, noside, std::get<0> (m_storage));
1561   }
1562
1563   enum exp_opcode opcode () const override
1564   { return OP_TYPE; }
1565
1566   bool constant_p () const override
1567   { return true; }
1568 };
1569
1570 /* Implement the "typeof" operation.  */
1571 class typeof_operation
1572   : public maybe_constant_operation<operation_up>
1573 {
1574 public:
1575
1576   using maybe_constant_operation::maybe_constant_operation;
1577
1578   value *evaluate (struct type *expect_type,
1579                    struct expression *exp,
1580                    enum noside noside) override
1581   {
1582     if (noside == EVAL_AVOID_SIDE_EFFECTS)
1583       return std::get<0> (m_storage)->evaluate (nullptr, exp,
1584                                                 EVAL_AVOID_SIDE_EFFECTS);
1585     else
1586       error (_("Attempt to use a type as an expression"));
1587   }
1588
1589   enum exp_opcode opcode () const override
1590   { return OP_TYPEOF; }
1591 };
1592
1593 /* Implement 'decltype'.  */
1594 class decltype_operation
1595   : public maybe_constant_operation<operation_up>
1596 {
1597 public:
1598
1599   using maybe_constant_operation::maybe_constant_operation;
1600
1601   value *evaluate (struct type *expect_type,
1602                    struct expression *exp,
1603                    enum noside noside) override
1604   {
1605     if (noside == EVAL_AVOID_SIDE_EFFECTS)
1606       {
1607         value *result
1608           = std::get<0> (m_storage)->evaluate (nullptr, exp,
1609                                                EVAL_AVOID_SIDE_EFFECTS);
1610         enum exp_opcode sub_op = std::get<0> (m_storage)->opcode ();
1611         if (sub_op == BINOP_SUBSCRIPT
1612             || sub_op == STRUCTOP_MEMBER
1613             || sub_op == STRUCTOP_MPTR
1614             || sub_op == UNOP_IND
1615             || sub_op == STRUCTOP_STRUCT
1616             || sub_op == STRUCTOP_PTR
1617             || sub_op == OP_SCOPE)
1618           {
1619             struct type *type = value_type (result);
1620
1621             if (!TYPE_IS_REFERENCE (type))
1622               {
1623                 type = lookup_lvalue_reference_type (type);
1624                 result = allocate_value (type);
1625               }
1626           }
1627
1628         return result;
1629       }
1630     else
1631       error (_("Attempt to use a type as an expression"));
1632   }
1633
1634   enum exp_opcode opcode () const override
1635   { return OP_DECLTYPE; }
1636 };
1637
1638 /* Implement 'typeid'.  */
1639 class typeid_operation
1640   : public tuple_holding_operation<operation_up>
1641 {
1642 public:
1643
1644   using tuple_holding_operation::tuple_holding_operation;
1645
1646   value *evaluate (struct type *expect_type,
1647                    struct expression *exp,
1648                    enum noside noside) override
1649   {
1650     enum exp_opcode sub_op = std::get<0> (m_storage)->opcode ();
1651     enum noside sub_noside
1652       = ((sub_op == OP_TYPE || sub_op == OP_DECLTYPE || sub_op == OP_TYPEOF)
1653          ? EVAL_AVOID_SIDE_EFFECTS
1654          : noside);
1655
1656     value *result = std::get<0> (m_storage)->evaluate (nullptr, exp,
1657                                                        sub_noside);
1658     if (noside != EVAL_NORMAL)
1659       return allocate_value (cplus_typeid_type (exp->gdbarch));
1660     return cplus_typeid (result);
1661   }
1662
1663   enum exp_opcode opcode () const override
1664   { return OP_TYPEID; }
1665 };
1666
1667 /* Implement the address-of operation.  */
1668 class unop_addr_operation
1669   : public maybe_constant_operation<operation_up>
1670 {
1671 public:
1672
1673   using maybe_constant_operation::maybe_constant_operation;
1674
1675   value *evaluate (struct type *expect_type,
1676                    struct expression *exp,
1677                    enum noside noside) override
1678   {
1679     /* C++: check for and handle pointer to members.  */
1680     return std::get<0> (m_storage)->evaluate_for_address (exp, noside);
1681   }
1682
1683   enum exp_opcode opcode () const override
1684   { return UNOP_ADDR; }
1685
1686   /* Return the subexpression.  */
1687   const operation_up &get_expression () const
1688   {
1689     return std::get<0> (m_storage);
1690   }
1691
1692 protected:
1693
1694   void do_generate_ax (struct expression *exp,
1695                        struct agent_expr *ax,
1696                        struct axs_value *value,
1697                        struct type *cast_type)
1698     override
1699   {
1700     gen_expr_unop (exp, UNOP_ADDR,
1701                    std::get<0> (this->m_storage).get (),
1702                    ax, value);
1703   }
1704 };
1705
1706 /* Implement 'sizeof'.  */
1707 class unop_sizeof_operation
1708   : public maybe_constant_operation<operation_up>
1709 {
1710 public:
1711
1712   using maybe_constant_operation::maybe_constant_operation;
1713
1714   value *evaluate (struct type *expect_type,
1715                    struct expression *exp,
1716                    enum noside noside) override
1717   {
1718     return std::get<0> (m_storage)->evaluate_for_sizeof (exp, noside);
1719   }
1720
1721   enum exp_opcode opcode () const override
1722   { return UNOP_SIZEOF; }
1723
1724 protected:
1725
1726   void do_generate_ax (struct expression *exp,
1727                        struct agent_expr *ax,
1728                        struct axs_value *value,
1729                        struct type *cast_type)
1730     override;
1731 };
1732
1733 /* Implement 'alignof'.  */
1734 class unop_alignof_operation
1735   : public maybe_constant_operation<operation_up>
1736 {
1737 public:
1738
1739   using maybe_constant_operation::maybe_constant_operation;
1740
1741   value *evaluate (struct type *expect_type,
1742                    struct expression *exp,
1743                    enum noside noside) override
1744   {
1745     value *val = std::get<0> (m_storage)->evaluate (nullptr, exp,
1746                                                     EVAL_AVOID_SIDE_EFFECTS);
1747     return eval_op_alignof (expect_type, exp, noside, val);
1748   }
1749
1750   enum exp_opcode opcode () const override
1751   { return UNOP_ALIGNOF; }
1752 };
1753
1754 /* Implement UNOP_MEMVAL.  */
1755 class unop_memval_operation
1756   : public tuple_holding_operation<operation_up, struct type *>
1757 {
1758 public:
1759
1760   using tuple_holding_operation::tuple_holding_operation;
1761
1762   value *evaluate (struct type *expect_type,
1763                    struct expression *exp,
1764                    enum noside noside) override
1765   {
1766     value *val = std::get<0> (m_storage)->evaluate (expect_type, exp, noside);
1767     return eval_op_memval (expect_type, exp, noside, val,
1768                            std::get<1> (m_storage));
1769   }
1770
1771   value *evaluate_for_sizeof (struct expression *exp,
1772                               enum noside noside) override;
1773
1774   value *evaluate_for_address (struct expression *exp,
1775                                enum noside noside) override;
1776
1777   enum exp_opcode opcode () const override
1778   { return UNOP_MEMVAL; }
1779
1780   /* Return the type referenced by this object.  */
1781   struct type *get_type () const
1782   {
1783     return std::get<1> (m_storage);
1784   }
1785
1786 protected:
1787
1788   void do_generate_ax (struct expression *exp,
1789                        struct agent_expr *ax,
1790                        struct axs_value *value,
1791                        struct type *cast_type)
1792     override;
1793 };
1794
1795 /* Implement UNOP_MEMVAL_TYPE.  */
1796 class unop_memval_type_operation
1797   : public tuple_holding_operation<operation_up, operation_up>
1798 {
1799 public:
1800
1801   using tuple_holding_operation::tuple_holding_operation;
1802
1803   value *evaluate (struct type *expect_type,
1804                    struct expression *exp,
1805                    enum noside noside) override
1806   {
1807     value *typeval
1808       = std::get<0> (m_storage)->evaluate (expect_type, exp,
1809                                            EVAL_AVOID_SIDE_EFFECTS);
1810     struct type *type = value_type (typeval);
1811     value *val = std::get<1> (m_storage)->evaluate (expect_type, exp, noside);
1812     return eval_op_memval (expect_type, exp, noside, val, type);
1813   }
1814
1815   value *evaluate_for_sizeof (struct expression *exp,
1816                               enum noside noside) override;
1817
1818   value *evaluate_for_address (struct expression *exp,
1819                                enum noside noside) override;
1820
1821   enum exp_opcode opcode () const override
1822   { return UNOP_MEMVAL_TYPE; }
1823
1824 protected:
1825
1826   void do_generate_ax (struct expression *exp,
1827                        struct agent_expr *ax,
1828                        struct axs_value *value,
1829                        struct type *cast_type)
1830     override;
1831 };
1832
1833 /* Implement the 'this' expression.  */
1834 class op_this_operation
1835   : public tuple_holding_operation<>
1836 {
1837 public:
1838
1839   using tuple_holding_operation::tuple_holding_operation;
1840
1841   value *evaluate (struct type *expect_type,
1842                    struct expression *exp,
1843                    enum noside noside) override
1844   {
1845     return value_of_this (exp->language_defn);
1846   }
1847
1848   enum exp_opcode opcode () const override
1849   { return OP_THIS; }
1850
1851 protected:
1852
1853   void do_generate_ax (struct expression *exp,
1854                        struct agent_expr *ax,
1855                        struct axs_value *value,
1856                        struct type *cast_type)
1857     override;
1858 };
1859
1860 /* Implement the "type instance" operation.  */
1861 class type_instance_operation
1862   : public tuple_holding_operation<type_instance_flags, std::vector<type *>,
1863                                    operation_up>
1864 {
1865 public:
1866
1867   using tuple_holding_operation::tuple_holding_operation;
1868
1869   value *evaluate (struct type *expect_type,
1870                    struct expression *exp,
1871                    enum noside noside) override;
1872
1873   enum exp_opcode opcode () const override
1874   { return TYPE_INSTANCE; }
1875 };
1876
1877 /* The assignment operator.  */
1878 class assign_operation
1879   : public tuple_holding_operation<operation_up, operation_up>
1880 {
1881 public:
1882
1883   using tuple_holding_operation::tuple_holding_operation;
1884
1885   value *evaluate (struct type *expect_type,
1886                    struct expression *exp,
1887                    enum noside noside) override
1888   {
1889     value *lhs = std::get<0> (m_storage)->evaluate (nullptr, exp, noside);
1890     /* Special-case assignments where the left-hand-side is a
1891        convenience variable -- in these, don't bother setting an
1892        expected type.  This avoids a weird case where re-assigning a
1893        string or array to an internal variable could error with "Too
1894        many array elements".  */
1895     struct type *xtype = (VALUE_LVAL (lhs) == lval_internalvar
1896                           ? nullptr
1897                           : value_type (lhs));
1898     value *rhs = std::get<1> (m_storage)->evaluate (xtype, exp, noside);
1899
1900     if (noside == EVAL_AVOID_SIDE_EFFECTS)
1901       return lhs;
1902     if (binop_user_defined_p (BINOP_ASSIGN, lhs, rhs))
1903       return value_x_binop (lhs, rhs, BINOP_ASSIGN, OP_NULL, noside);
1904     else
1905       return value_assign (lhs, rhs);
1906   }
1907
1908   enum exp_opcode opcode () const override
1909   { return BINOP_ASSIGN; }
1910
1911   /* Return the left-hand-side of the assignment.  */
1912   operation *get_lhs () const
1913   {
1914     return std::get<0> (m_storage).get ();
1915   }
1916
1917 protected:
1918
1919   void do_generate_ax (struct expression *exp,
1920                        struct agent_expr *ax,
1921                        struct axs_value *value,
1922                        struct type *cast_type)
1923     override;
1924 };
1925
1926 /* Assignment with modification, like "+=".  */
1927 class assign_modify_operation
1928   : public tuple_holding_operation<exp_opcode, operation_up, operation_up>
1929 {
1930 public:
1931
1932   using tuple_holding_operation::tuple_holding_operation;
1933
1934   value *evaluate (struct type *expect_type,
1935                    struct expression *exp,
1936                    enum noside noside) override
1937   {
1938     value *lhs = std::get<1> (m_storage)->evaluate (nullptr, exp, noside);
1939     value *rhs = std::get<2> (m_storage)->evaluate (expect_type, exp, noside);
1940     return eval_binop_assign_modify (expect_type, exp, noside,
1941                                      std::get<0> (m_storage), lhs, rhs);
1942   }
1943
1944   enum exp_opcode opcode () const override
1945   { return BINOP_ASSIGN_MODIFY; }
1946
1947 protected:
1948
1949   void do_generate_ax (struct expression *exp,
1950                        struct agent_expr *ax,
1951                        struct axs_value *value,
1952                        struct type *cast_type)
1953     override;
1954 };
1955
1956 /* Not a cast!  Extract a value of a given type from the contents of a
1957    value.  The new value is extracted from the least significant bytes
1958    of the old value.  The new value's type must be no bigger than the
1959    old values type.  */
1960 class unop_extract_operation
1961   : public maybe_constant_operation<operation_up, struct type *>
1962 {
1963 public:
1964
1965   using maybe_constant_operation::maybe_constant_operation;
1966
1967   value *evaluate (struct type *expect_type, struct expression *exp,
1968                    enum noside noside) override;
1969
1970   enum exp_opcode opcode () const override
1971   { return UNOP_EXTRACT; }
1972
1973   /* Return the type referenced by this object.  */
1974   struct type *get_type () const
1975   {
1976     return std::get<1> (m_storage);
1977   }
1978
1979 protected:
1980
1981   void do_generate_ax (struct expression *exp,
1982                        struct agent_expr *ax,
1983                        struct axs_value *value,
1984                        struct type *cast_type) override;
1985 };
1986
1987 /* A type cast.  */
1988 class unop_cast_operation
1989   : public maybe_constant_operation<operation_up, struct type *>
1990 {
1991 public:
1992
1993   using maybe_constant_operation::maybe_constant_operation;
1994
1995   value *evaluate (struct type *expect_type,
1996                    struct expression *exp,
1997                    enum noside noside) override
1998   {
1999     return std::get<0> (m_storage)->evaluate_for_cast (std::get<1> (m_storage),
2000                                                        exp, noside);
2001   }
2002
2003   enum exp_opcode opcode () const override
2004   { return UNOP_CAST; }
2005
2006   /* Return the type referenced by this object.  */
2007   struct type *get_type () const
2008   {
2009     return std::get<1> (m_storage);
2010   }
2011
2012 protected:
2013
2014   void do_generate_ax (struct expression *exp,
2015                        struct agent_expr *ax,
2016                        struct axs_value *value,
2017                        struct type *cast_type)
2018     override;
2019 };
2020
2021 /* A cast, but the type comes from an expression, not a "struct
2022    type".  */
2023 class unop_cast_type_operation
2024   : public maybe_constant_operation<operation_up, operation_up>
2025 {
2026 public:
2027
2028   using maybe_constant_operation::maybe_constant_operation;
2029
2030   value *evaluate (struct type *expect_type,
2031                    struct expression *exp,
2032                    enum noside noside) override
2033   {
2034     value *val = std::get<0> (m_storage)->evaluate (nullptr, exp,
2035                                                     EVAL_AVOID_SIDE_EFFECTS);
2036     return std::get<1> (m_storage)->evaluate_for_cast (value_type (val),
2037                                                        exp, noside);
2038   }
2039
2040   enum exp_opcode opcode () const override
2041   { return UNOP_CAST_TYPE; }
2042
2043 protected:
2044
2045   void do_generate_ax (struct expression *exp,
2046                        struct agent_expr *ax,
2047                        struct axs_value *value,
2048                        struct type *cast_type)
2049     override;
2050 };
2051
2052 typedef value *cxx_cast_ftype (struct type *, value *);
2053
2054 /* This implements dynamic_cast and reinterpret_cast.  static_cast and
2055    const_cast are handled by the ordinary case operations.  */
2056 template<exp_opcode OP, cxx_cast_ftype FUNC>
2057 class cxx_cast_operation
2058   : public maybe_constant_operation<operation_up, operation_up>
2059 {
2060 public:
2061
2062   using maybe_constant_operation::maybe_constant_operation;
2063
2064   value *evaluate (struct type *expect_type,
2065                    struct expression *exp,
2066                    enum noside noside) override
2067   {
2068     value *val = std::get<0> (m_storage)->evaluate (nullptr, exp,
2069                                                     EVAL_AVOID_SIDE_EFFECTS);
2070     struct type *type = value_type (val);
2071     value *rhs = std::get<1> (m_storage)->evaluate (type, exp, noside);
2072     return FUNC (type, rhs);
2073   }
2074
2075   enum exp_opcode opcode () const override
2076   { return OP; }
2077 };
2078
2079 using dynamic_cast_operation = cxx_cast_operation<UNOP_DYNAMIC_CAST,
2080                                                   value_dynamic_cast>;
2081 using reinterpret_cast_operation = cxx_cast_operation<UNOP_REINTERPRET_CAST,
2082                                                       value_reinterpret_cast>;
2083
2084 /* Multi-dimensional subscripting.  */
2085 class multi_subscript_operation
2086   : public tuple_holding_operation<operation_up, std::vector<operation_up>>
2087 {
2088 public:
2089
2090   using tuple_holding_operation::tuple_holding_operation;
2091
2092   value *evaluate (struct type *expect_type,
2093                    struct expression *exp,
2094                    enum noside noside) override;
2095
2096   enum exp_opcode opcode () const override
2097   { return MULTI_SUBSCRIPT; }
2098 };
2099
2100 /* The "&&" operator.  */
2101 class logical_and_operation
2102   : public maybe_constant_operation<operation_up, operation_up>
2103 {
2104 public:
2105
2106   using maybe_constant_operation::maybe_constant_operation;
2107
2108   value *evaluate (struct type *expect_type,
2109                    struct expression *exp,
2110                    enum noside noside) override;
2111
2112   enum exp_opcode opcode () const override
2113   { return BINOP_LOGICAL_AND; }
2114
2115 protected:
2116
2117   void do_generate_ax (struct expression *exp,
2118                        struct agent_expr *ax,
2119                        struct axs_value *value,
2120                        struct type *cast_type)
2121     override;
2122 };
2123
2124 /* The "||" operator.  */
2125 class logical_or_operation
2126   : public maybe_constant_operation<operation_up, operation_up>
2127 {
2128 public:
2129
2130   using maybe_constant_operation::maybe_constant_operation;
2131
2132   value *evaluate (struct type *expect_type,
2133                    struct expression *exp,
2134                    enum noside noside) override;
2135
2136   enum exp_opcode opcode () const override
2137   { return BINOP_LOGICAL_OR; }
2138
2139 protected:
2140
2141   void do_generate_ax (struct expression *exp,
2142                        struct agent_expr *ax,
2143                        struct axs_value *value,
2144                        struct type *cast_type)
2145     override;
2146 };
2147
2148 /* This class implements ADL (aka Koenig) function calls for C++.  It
2149    holds the name of the function to call, the block in which the
2150    lookup should be done, and a vector of arguments.  */
2151 class adl_func_operation
2152   : public tuple_holding_operation<std::string, const block *,
2153                                    std::vector<operation_up>>
2154 {
2155 public:
2156
2157   using tuple_holding_operation::tuple_holding_operation;
2158
2159   value *evaluate (struct type *expect_type,
2160                    struct expression *exp,
2161                    enum noside noside) override;
2162
2163   enum exp_opcode opcode () const override
2164   { return OP_ADL_FUNC; }
2165 };
2166
2167 /* The OP_ARRAY operation.  */
2168 class array_operation
2169   : public tuple_holding_operation<int, int, std::vector<operation_up>>
2170 {
2171 public:
2172
2173   using tuple_holding_operation::tuple_holding_operation;
2174
2175   value *evaluate (struct type *expect_type,
2176                    struct expression *exp,
2177                    enum noside noside) override;
2178
2179   enum exp_opcode opcode () const override
2180   { return OP_ARRAY; }
2181
2182 private:
2183
2184   struct value *evaluate_struct_tuple (struct value *struct_val,
2185                                        struct expression *exp,
2186                                        enum noside noside, int nargs);
2187 };
2188
2189 /* A function call.  This holds the callee operation and the
2190    arguments.  */
2191 class funcall_operation
2192   : public tuple_holding_operation<operation_up, std::vector<operation_up>>
2193 {
2194 public:
2195
2196   using tuple_holding_operation::tuple_holding_operation;
2197
2198   value *evaluate (struct type *expect_type,
2199                    struct expression *exp,
2200                    enum noside noside) override
2201   {
2202     return std::get<0> (m_storage)->evaluate_funcall (expect_type, exp, noside,
2203                                                       std::get<1> (m_storage));
2204   }
2205
2206   enum exp_opcode opcode () const override
2207   { return OP_FUNCALL; }
2208 };
2209
2210 } /* namespace expr */
2211
2212 #endif /* EXPOP_H */