1 // ABI Support -*- C++ -*- 2 3 // Copyright (C) 2000-2014 Free Software Foundation, Inc. 4 // 5 // This file is part of GCC. 6 // 7 // GCC 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, or (at your option) 10 // any later version. 11 // 12 // GCC 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 // Under Section 7 of GPL version 3, you are granted additional 18 // permissions described in the GCC Runtime Library Exception, version 19 // 3.1, as published by the Free Software Foundation. 20 21 // You should have received a copy of the GNU General Public License and 22 // a copy of the GCC Runtime Library Exception along with this program; 23 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 24 // <http://www.gnu.org/licenses/>. 25 26 // Written by Nathan Sidwell, Codesourcery LLC, <nathan (at) codesourcery.com> 27 28 /* This file declares the new abi entry points into the runtime. It is not 29 normally necessary for user programs to include this header, or use the 30 entry points directly. However, this header is available should that be 31 needed. 32 33 Some of the entry points are intended for both C and C++, thus this header 34 is includable from both C and C++. Though the C++ specific parts are not 35 available in C, naturally enough. */ 36 37 /** @file cxxabi.h 38 * The header provides an interface to the C++ ABI. 39 */ 40 41 #ifndef _CXXABI_H 42 #define _CXXABI_H 1 43 44 #pragma GCC system_header 45 46 #pragma GCC visibility push(default) 47 48 #include <stddef.h> 49 #include <bits/c++config.h> 50 #include <bits/cxxabi_tweaks.h> 51 #include <bits/cxxabi_forced.h> 52 53 #ifndef _GLIBCXX_CDTOR_CALLABI 54 #define _GLIBCXX_CDTOR_CALLABI 55 #endif 56 57 #ifdef __cplusplus 58 namespace __cxxabiv1 59 { 60 extern "C" 61 { 62 #endif 63 64 typedef __cxa_cdtor_return_type (*__cxa_cdtor_type)(void *); 65 66 // Allocate array. 67 void* 68 __cxa_vec_new(size_t __element_count, size_t __element_size, 69 size_t __padding_size, __cxa_cdtor_type __constructor, 70 __cxa_cdtor_type __destructor); 71 72 void* 73 __cxa_vec_new2(size_t __element_count, size_t __element_size, 74 size_t __padding_size, __cxa_cdtor_type __constructor, 75 __cxa_cdtor_type __destructor, void *(*__alloc) (size_t), 76 void (*__dealloc) (void*)); 77 78 void* 79 __cxa_vec_new3(size_t __element_count, size_t __element_size, 80 size_t __padding_size, __cxa_cdtor_type __constructor, 81 __cxa_cdtor_type __destructor, void *(*__alloc) (size_t), 82 void (*__dealloc) (void*, size_t)); 83 84 // Construct array. 85 __cxa_vec_ctor_return_type 86 __cxa_vec_ctor(void* __array_address, size_t __element_count, 87 size_t __element_size, __cxa_cdtor_type __constructor, 88 __cxa_cdtor_type __destructor); 89 90 __cxa_vec_ctor_return_type 91 __cxa_vec_cctor(void* __dest_array, void* __src_array, 92 size_t __element_count, size_t __element_size, 93 __cxa_cdtor_return_type (*__constructor) (void*, void*), 94 __cxa_cdtor_type __destructor); 95 96 // Destruct array. 97 void 98 __cxa_vec_dtor(void* __array_address, size_t __element_count, 99 size_t __element_size, __cxa_cdtor_type __destructor); 100 101 void 102 __cxa_vec_cleanup(void* __array_address, size_t __element_count, size_t __s, 103 __cxa_cdtor_type __destructor) _GLIBCXX_NOTHROW; 104 105 // Destruct and release array. 106 void 107 __cxa_vec_delete(void* __array_address, size_t __element_size, 108 size_t __padding_size, __cxa_cdtor_type __destructor); 109 110 void 111 __cxa_vec_delete2(void* __array_address, size_t __element_size, 112 size_t __padding_size, __cxa_cdtor_type __destructor, 113 void (*__dealloc) (void*)); 114 115 void 116 __cxa_vec_delete3(void* __array_address, size_t __element_size, 117 size_t __padding_size, __cxa_cdtor_type __destructor, 118 void (*__dealloc) (void*, size_t)); 119 120 int 121 __cxa_guard_acquire(__guard*); 122 123 void 124 __cxa_guard_release(__guard*) _GLIBCXX_NOTHROW; 125 126 void 127 __cxa_guard_abort(__guard*) _GLIBCXX_NOTHROW; 128 129 // DSO destruction. 130 int 131 __cxa_atexit(void (*)(void*), void*, void*) _GLIBCXX_NOTHROW; 132 133 int 134 __cxa_finalize(void*); 135 136 // TLS destruction. 137 int 138 __cxa_thread_atexit(void (*)(void*), void*, void *) _GLIBCXX_NOTHROW; 139 140 // Pure virtual functions. 141 void 142 __cxa_pure_virtual(void) __attribute__ ((__noreturn__)); 143 144 void 145 __cxa_deleted_virtual(void) __attribute__ ((__noreturn__)); 146 147 // Exception handling auxiliary. 148 void 149 __cxa_bad_cast() __attribute__((__noreturn__)); 150 151 void 152 __cxa_bad_typeid() __attribute__((__noreturn__)); 153 154 void 155 __cxa_throw_bad_array_new_length() __attribute__((__noreturn__)); 156 157 void 158 __cxa_throw_bad_array_length() __attribute__((__noreturn__)); 159 160 /** 161 * @brief Demangling routine. 162 * ABI-mandated entry point in the C++ runtime library for demangling. 163 * 164 * @param __mangled_name A NUL-terminated character string 165 * containing the name to be demangled. 166 * 167 * @param __output_buffer A region of memory, allocated with 168 * malloc, of @a *__length bytes, into which the demangled name is 169 * stored. If @a __output_buffer is not long enough, it is 170 * expanded using realloc. @a __output_buffer may instead be NULL; 171 * in that case, the demangled name is placed in a region of memory 172 * allocated with malloc. 173 * 174 * @param __length If @a __length is non-NULL, the length of the 175 * buffer containing the demangled name is placed in @a *__length. 176 * 177 * @param __status @a *__status is set to one of the following values: 178 * 0: The demangling operation succeeded. 179 * -1: A memory allocation failure occurred. 180 * -2: @a mangled_name is not a valid name under the C++ ABI mangling rules. 181 * -3: One of the arguments is invalid. 182 * 183 * @return A pointer to the start of the NUL-terminated demangled 184 * name, or NULL if the demangling fails. The caller is 185 * responsible for deallocating this memory using @c free. 186 * 187 * The demangling is performed using the C++ ABI mangling rules, 188 * with GNU extensions. For example, this function is used in 189 * __gnu_cxx::__verbose_terminate_handler. 190 * 191 * See http://gcc.gnu.org/onlinedocs/libstdc++/manual/bk01pt12ch39.html 192 * for other examples of use. 193 * 194 * @note The same demangling functionality is available via 195 * libiberty (@c <libiberty/demangle.h> and @c libiberty.a) in GCC 196 * 3.1 and later, but that requires explicit installation (@c 197 * --enable-install-libiberty) and uses a different API, although 198 * the ABI is unchanged. 199 */ 200 char* 201 __cxa_demangle(const char* __mangled_name, char* __output_buffer, 202 size_t* __length, int* __status); 203 204 #ifdef __cplusplus 205 } 206 } // namespace __cxxabiv1 207 #endif 208 209 #ifdef __cplusplus 210 211 #include <typeinfo> 212 213 namespace __cxxabiv1 214 { 215 // Type information for int, float etc. 216 class __fundamental_type_info : public std::type_info 217 { 218 public: 219 explicit 220 __fundamental_type_info(const char* __n) : std::type_info(__n) { } 221 222 virtual 223 ~__fundamental_type_info(); 224 }; 225 226 // Type information for array objects. 227 class __array_type_info : public std::type_info 228 { 229 public: 230 explicit 231 __array_type_info(const char* __n) : std::type_info(__n) { } 232 233 virtual 234 ~__array_type_info(); 235 }; 236 237 // Type information for functions (both member and non-member). 238 class __function_type_info : public std::type_info 239 { 240 public: 241 explicit 242 __function_type_info(const char* __n) : std::type_info(__n) { } 243 244 virtual 245 ~__function_type_info(); 246 247 protected: 248 // Implementation defined member function. 249 virtual bool 250 __is_function_p() const; 251 }; 252 253 // Type information for enumerations. 254 class __enum_type_info : public std::type_info 255 { 256 public: 257 explicit 258 __enum_type_info(const char* __n) : std::type_info(__n) { } 259 260 virtual 261 ~__enum_type_info(); 262 }; 263 264 // Common type information for simple pointers and pointers to member. 265 class __pbase_type_info : public std::type_info 266 { 267 public: 268 unsigned int __flags; // Qualification of the target object. 269 const std::type_info* __pointee; // Type of pointed to object. 270 271 explicit 272 __pbase_type_info(const char* __n, int __quals, 273 const std::type_info* __type) 274 : std::type_info(__n), __flags(__quals), __pointee(__type) 275 { } 276 277 virtual 278 ~__pbase_type_info(); 279 280 // Implementation defined type. 281 enum __masks 282 { 283 __const_mask = 0x1, 284 __volatile_mask = 0x2, 285 __restrict_mask = 0x4, 286 __incomplete_mask = 0x8, 287 __incomplete_class_mask = 0x10 288 }; 289 290 protected: 291 __pbase_type_info(const __pbase_type_info&); 292 293 __pbase_type_info& 294 operator=(const __pbase_type_info&); 295 296 // Implementation defined member functions. 297 virtual bool 298 __do_catch(const std::type_info* __thr_type, void** __thr_obj, 299 unsigned int __outer) const; 300 301 inline virtual bool 302 __pointer_catch(const __pbase_type_info* __thr_type, void** __thr_obj, 303 unsigned __outer) const; 304 }; 305 306 // Type information for simple pointers. 307 class __pointer_type_info : public __pbase_type_info 308 { 309 public: 310 explicit 311 __pointer_type_info(const char* __n, int __quals, 312 const std::type_info* __type) 313 : __pbase_type_info (__n, __quals, __type) { } 314 315 316 virtual 317 ~__pointer_type_info(); 318 319 protected: 320 // Implementation defined member functions. 321 virtual bool 322 __is_pointer_p() const; 323 324 virtual bool 325 __pointer_catch(const __pbase_type_info* __thr_type, void** __thr_obj, 326 unsigned __outer) const; 327 }; 328 329 class __class_type_info; 330 331 // Type information for a pointer to member variable. 332 class __pointer_to_member_type_info : public __pbase_type_info 333 { 334 public: 335 __class_type_info* __context; // Class of the member. 336 337 explicit 338 __pointer_to_member_type_info(const char* __n, int __quals, 339 const std::type_info* __type, 340 __class_type_info* __klass) 341 : __pbase_type_info(__n, __quals, __type), __context(__klass) { } 342 343 virtual 344 ~__pointer_to_member_type_info(); 345 346 protected: 347 __pointer_to_member_type_info(const __pointer_to_member_type_info&); 348 349 __pointer_to_member_type_info& 350 operator=(const __pointer_to_member_type_info&); 351 352 // Implementation defined member function. 353 virtual bool 354 __pointer_catch(const __pbase_type_info* __thr_type, void** __thr_obj, 355 unsigned __outer) const; 356 }; 357 358 // Helper class for __vmi_class_type. 359 class __base_class_type_info 360 { 361 public: 362 const __class_type_info* __base_type; // Base class type. 363 #ifdef _GLIBCXX_LLP64 364 long long __offset_flags; // Offset and info. 365 #else 366 long __offset_flags; // Offset and info. 367 #endif 368 369 enum __offset_flags_masks 370 { 371 __virtual_mask = 0x1, 372 __public_mask = 0x2, 373 __hwm_bit = 2, 374 __offset_shift = 8 // Bits to shift offset. 375 }; 376 377 // Implementation defined member functions. 378 bool 379 __is_virtual_p() const 380 { return __offset_flags & __virtual_mask; } 381 382 bool 383 __is_public_p() const 384 { return __offset_flags & __public_mask; } 385 386 ptrdiff_t 387 __offset() const 388 { 389 // This shift, being of a signed type, is implementation 390 // defined. GCC implements such shifts as arithmetic, which is 391 // what we want. 392 return static_cast<ptrdiff_t>(__offset_flags) >> __offset_shift; 393 } 394 }; 395 396 // Type information for a class. 397 class __class_type_info : public std::type_info 398 { 399 public: 400 explicit 401 __class_type_info (const char *__n) : type_info(__n) { } 402 403 virtual 404 ~__class_type_info (); 405 406 // Implementation defined types. 407 // The type sub_kind tells us about how a base object is contained 408 // within a derived object. We often do this lazily, hence the 409 // UNKNOWN value. At other times we may use NOT_CONTAINED to mean 410 // not publicly contained. 411 enum __sub_kind 412 { 413 // We have no idea. 414 __unknown = 0, 415 416 // Not contained within us (in some circumstances this might 417 // mean not contained publicly) 418 __not_contained, 419 420 // Contained ambiguously. 421 __contained_ambig, 422 423 // Via a virtual path. 424 __contained_virtual_mask = __base_class_type_info::__virtual_mask, 425 426 // Via a public path. 427 __contained_public_mask = __base_class_type_info::__public_mask, 428 429 // Contained within us. 430 __contained_mask = 1 << __base_class_type_info::__hwm_bit, 431 432 __contained_private = __contained_mask, 433 __contained_public = __contained_mask | __contained_public_mask 434 }; 435 436 struct __upcast_result; 437 struct __dyncast_result; 438 439 protected: 440 // Implementation defined member functions. 441 virtual bool 442 __do_upcast(const __class_type_info* __dst_type, void**__obj_ptr) const; 443 444 virtual bool 445 __do_catch(const type_info* __thr_type, void** __thr_obj, 446 unsigned __outer) const; 447 448 public: 449 // Helper for upcast. See if DST is us, or one of our bases. 450 // Return false if not found, true if found. 451 virtual bool 452 __do_upcast(const __class_type_info* __dst, const void* __obj, 453 __upcast_result& __restrict __result) const; 454 455 // Indicate whether SRC_PTR of type SRC_TYPE is contained publicly 456 // within OBJ_PTR. OBJ_PTR points to a base object of our type, 457 // which is the destination type. SRC2DST indicates how SRC 458 // objects might be contained within this type. If SRC_PTR is one 459 // of our SRC_TYPE bases, indicate the virtuality. Returns 460 // not_contained for non containment or private containment. 461 inline __sub_kind 462 __find_public_src(ptrdiff_t __src2dst, const void* __obj_ptr, 463 const __class_type_info* __src_type, 464 const void* __src_ptr) const; 465 466 // Helper for dynamic cast. ACCESS_PATH gives the access from the 467 // most derived object to this base. DST_TYPE indicates the 468 // desired type we want. OBJ_PTR points to a base of our type 469 // within the complete object. SRC_TYPE indicates the static type 470 // started from and SRC_PTR points to that base within the most 471 // derived object. Fill in RESULT with what we find. Return true 472 // if we have located an ambiguous match. 473 virtual bool 474 __do_dyncast(ptrdiff_t __src2dst, __sub_kind __access_path, 475 const __class_type_info* __dst_type, const void* __obj_ptr, 476 const __class_type_info* __src_type, const void* __src_ptr, 477 __dyncast_result& __result) const; 478 479 // Helper for find_public_subobj. SRC2DST indicates how SRC_TYPE 480 // bases are inherited by the type started from -- which is not 481 // necessarily the current type. The current type will be a base 482 // of the destination type. OBJ_PTR points to the current base. 483 virtual __sub_kind 484 __do_find_public_src(ptrdiff_t __src2dst, const void* __obj_ptr, 485 const __class_type_info* __src_type, 486 const void* __src_ptr) const; 487 }; 488 489 // Type information for a class with a single non-virtual base. 490 class __si_class_type_info : public __class_type_info 491 { 492 public: 493 const __class_type_info* __base_type; 494 495 explicit 496 __si_class_type_info(const char *__n, const __class_type_info *__base) 497 : __class_type_info(__n), __base_type(__base) { } 498 499 virtual 500 ~__si_class_type_info(); 501 502 protected: 503 __si_class_type_info(const __si_class_type_info&); 504 505 __si_class_type_info& 506 operator=(const __si_class_type_info&); 507 508 // Implementation defined member functions. 509 virtual bool 510 __do_dyncast(ptrdiff_t __src2dst, __sub_kind __access_path, 511 const __class_type_info* __dst_type, const void* __obj_ptr, 512 const __class_type_info* __src_type, const void* __src_ptr, 513 __dyncast_result& __result) const; 514 515 virtual __sub_kind 516 __do_find_public_src(ptrdiff_t __src2dst, const void* __obj_ptr, 517 const __class_type_info* __src_type, 518 const void* __sub_ptr) const; 519 520 virtual bool 521 __do_upcast(const __class_type_info*__dst, const void*__obj, 522 __upcast_result& __restrict __result) const; 523 }; 524 525 // Type information for a class with multiple and/or virtual bases. 526 class __vmi_class_type_info : public __class_type_info 527 { 528 public: 529 unsigned int __flags; // Details about the class hierarchy. 530 unsigned int __base_count; // Number of direct bases. 531 532 // The array of bases uses the trailing array struct hack so this 533 // class is not constructable with a normal constructor. It is 534 // internally generated by the compiler. 535 __base_class_type_info __base_info[1]; // Array of bases. 536 537 explicit 538 __vmi_class_type_info(const char* __n, int ___flags) 539 : __class_type_info(__n), __flags(___flags), __base_count(0) { } 540 541 virtual 542 ~__vmi_class_type_info(); 543 544 // Implementation defined types. 545 enum __flags_masks 546 { 547 __non_diamond_repeat_mask = 0x1, // Distinct instance of repeated base. 548 __diamond_shaped_mask = 0x2, // Diamond shaped multiple inheritance. 549 __flags_unknown_mask = 0x10 550 }; 551 552 protected: 553 // Implementation defined member functions. 554 virtual bool 555 __do_dyncast(ptrdiff_t __src2dst, __sub_kind __access_path, 556 const __class_type_info* __dst_type, const void* __obj_ptr, 557 const __class_type_info* __src_type, const void* __src_ptr, 558 __dyncast_result& __result) const; 559 560 virtual __sub_kind 561 __do_find_public_src(ptrdiff_t __src2dst, const void* __obj_ptr, 562 const __class_type_info* __src_type, 563 const void* __src_ptr) const; 564 565 virtual bool 566 __do_upcast(const __class_type_info* __dst, const void* __obj, 567 __upcast_result& __restrict __result) const; 568 }; 569 570 // Exception handling forward declarations. 571 struct __cxa_exception; 572 struct __cxa_refcounted_exception; 573 struct __cxa_dependent_exception; 574 struct __cxa_eh_globals; 575 576 extern "C" 577 { 578 // Dynamic cast runtime. 579 580 // src2dst has the following possible values 581 // >-1: src_type is a unique public non-virtual base of dst_type 582 // dst_ptr + src2dst == src_ptr 583 // -1: unspecified relationship 584 // -2: src_type is not a public base of dst_type 585 // -3: src_type is a multiple public non-virtual base of dst_type 586 void* 587 __dynamic_cast(const void* __src_ptr, // Starting object. 588 const __class_type_info* __src_type, // Static type of object. 589 const __class_type_info* __dst_type, // Desired target type. 590 ptrdiff_t __src2dst); // How src and dst are related. 591 592 593 // Exception handling runtime. 594 595 // The __cxa_eh_globals for the current thread can be obtained by using 596 // either of the following functions. The "fast" version assumes at least 597 // one prior call of __cxa_get_globals has been made from the current 598 // thread, so no initialization is necessary. 599 __cxa_eh_globals* 600 __cxa_get_globals() _GLIBCXX_NOTHROW __attribute__ ((__const__)); 601 602 __cxa_eh_globals* 603 __cxa_get_globals_fast() _GLIBCXX_NOTHROW __attribute__ ((__const__)); 604 605 // Allocate memory for the primary exception plus the thrown object. 606 void* 607 __cxa_allocate_exception(size_t) _GLIBCXX_NOTHROW; 608 609 // Free the space allocated for the primary exception. 610 void 611 __cxa_free_exception(void*) _GLIBCXX_NOTHROW; 612 613 // Throw the exception. 614 void 615 __cxa_throw(void*, std::type_info*, void (_GLIBCXX_CDTOR_CALLABI *) (void *)) 616 __attribute__((__noreturn__)); 617 618 // Used to implement exception handlers. 619 void* 620 __cxa_get_exception_ptr(void*) _GLIBCXX_NOTHROW __attribute__ ((__pure__)); 621 622 void* 623 __cxa_begin_catch(void*) _GLIBCXX_NOTHROW; 624 625 void 626 __cxa_end_catch(); 627 628 void 629 __cxa_rethrow() __attribute__((__noreturn__)); 630 631 // Returns the type_info for the currently handled exception [15.3/8], or 632 // null if there is none. 633 std::type_info* 634 __cxa_current_exception_type() _GLIBCXX_NOTHROW __attribute__ ((__pure__)); 635 636 // GNU Extensions. 637 638 // Allocate memory for a dependent exception. 639 __cxa_dependent_exception* 640 __cxa_allocate_dependent_exception() _GLIBCXX_NOTHROW; 641 642 // Free the space allocated for the dependent exception. 643 void 644 __cxa_free_dependent_exception(__cxa_dependent_exception*) _GLIBCXX_NOTHROW; 645 646 } // extern "C" 647 648 // A magic placeholder class that can be caught by reference 649 // to recognize foreign exceptions. 650 class __foreign_exception 651 { 652 virtual ~__foreign_exception() throw(); 653 virtual void __pure_dummy() = 0; // prevent catch by value 654 }; 655 656 } // namespace __cxxabiv1 657 658 /** @namespace abi 659 * @brief The cross-vendor C++ Application Binary Interface. A 660 * namespace alias to __cxxabiv1, but user programs should use the 661 * alias 'abi'. 662 * 663 * A brief overview of an ABI is given in the libstdc++ FAQ, question 664 * 5.8 (you may have a copy of the FAQ locally, or you can view the online 665 * version at http://gcc.gnu.org/onlinedocs/libstdc++/faq.html#5_8 ). 666 * 667 * GCC subscribes to a cross-vendor ABI for C++, sometimes 668 * called the IA64 ABI because it happens to be the native ABI for that 669 * platform. It is summarized at http://www.codesourcery.com/cxx-abi/ 670 * along with the current specification. 671 * 672 * For users of GCC greater than or equal to 3.x, entry points are 673 * available in <cxxabi.h>, which notes, <em>'It is not normally 674 * necessary for user programs to include this header, or use the 675 * entry points directly. However, this header is available should 676 * that be needed.'</em> 677 */ 678 namespace abi = __cxxabiv1; 679 680 namespace __gnu_cxx 681 { 682 /** 683 * @brief Exception thrown by __cxa_guard_acquire. 684 * @ingroup exceptions 685 * 686 * 6.7[stmt.dcl]/4: If control re-enters the declaration (recursively) 687 * while the object is being initialized, the behavior is undefined. 688 * 689 * Since we already have a library function to handle locking, we might 690 * as well check for this situation and throw an exception. 691 * We use the second byte of the guard variable to remember that we're 692 * in the middle of an initialization. 693 */ 694 class recursive_init_error: public std::exception 695 { 696 public: 697 recursive_init_error() throw() { } 698 virtual ~recursive_init_error() throw (); 699 }; 700 } 701 #endif // __cplusplus 702 703 #pragma GCC visibility pop 704 705 #endif // __CXXABI_H 706
