1 // ABI Support -*- C++ -*- 2 3 // Copyright (C) 2000-2013 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@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 auxillary. 148 void 149 __cxa_bad_cast() __attribute__((__noreturn__)); 150 151 void 152 __cxa_bad_typeid() __attribute__((__noreturn__)); 153 154 155 /** 156 * @brief Demangling routine. 157 * ABI-mandated entry point in the C++ runtime library for demangling. 158 * 159 * @param __mangled_name A NUL-terminated character string 160 * containing the name to be demangled. 161 * 162 * @param __output_buffer A region of memory, allocated with 163 * malloc, of @a *__length bytes, into which the demangled name is 164 * stored. If @a __output_buffer is not long enough, it is 165 * expanded using realloc. @a __output_buffer may instead be NULL; 166 * in that case, the demangled name is placed in a region of memory 167 * allocated with malloc. 168 * 169 * @param __length If @a __length is non-NULL, the length of the 170 * buffer containing the demangled name is placed in @a *__length. 171 * 172 * @param __status @a *__status is set to one of the following values: 173 * 0: The demangling operation succeeded. 174 * -1: A memory allocation failure occurred. 175 * -2: @a mangled_name is not a valid name under the C++ ABI mangling rules. 176 * -3: One of the arguments is invalid. 177 * 178 * @return A pointer to the start of the NUL-terminated demangled 179 * name, or NULL if the demangling fails. The caller is 180 * responsible for deallocating this memory using @c free. 181 * 182 * The demangling is performed using the C++ ABI mangling rules, 183 * with GNU extensions. For example, this function is used in 184 * __gnu_cxx::__verbose_terminate_handler. 185 * 186 * See http://gcc.gnu.org/onlinedocs/libstdc++/manual/bk01pt12ch39.html 187 * for other examples of use. 188 * 189 * @note The same demangling functionality is available via 190 * libiberty (@c <libiberty/demangle.h> and @c libiberty.a) in GCC 191 * 3.1 and later, but that requires explicit installation (@c 192 * --enable-install-libiberty) and uses a different API, although 193 * the ABI is unchanged. 194 */ 195 char* 196 __cxa_demangle(const char* __mangled_name, char* __output_buffer, 197 size_t* __length, int* __status); 198 199 #ifdef __cplusplus 200 } 201 } // namespace __cxxabiv1 202 #endif 203 204 #ifdef __cplusplus 205 206 #include <typeinfo> 207 208 namespace __cxxabiv1 209 { 210 // Type information for int, float etc. 211 class __fundamental_type_info : public std::type_info 212 { 213 public: 214 explicit 215 __fundamental_type_info(const char* __n) : std::type_info(__n) { } 216 217 virtual 218 ~__fundamental_type_info(); 219 }; 220 221 // Type information for array objects. 222 class __array_type_info : public std::type_info 223 { 224 public: 225 explicit 226 __array_type_info(const char* __n) : std::type_info(__n) { } 227 228 virtual 229 ~__array_type_info(); 230 }; 231 232 // Type information for functions (both member and non-member). 233 class __function_type_info : public std::type_info 234 { 235 public: 236 explicit 237 __function_type_info(const char* __n) : std::type_info(__n) { } 238 239 virtual 240 ~__function_type_info(); 241 242 protected: 243 // Implementation defined member function. 244 virtual bool 245 __is_function_p() const; 246 }; 247 248 // Type information for enumerations. 249 class __enum_type_info : public std::type_info 250 { 251 public: 252 explicit 253 __enum_type_info(const char* __n) : std::type_info(__n) { } 254 255 virtual 256 ~__enum_type_info(); 257 }; 258 259 // Common type information for simple pointers and pointers to member. 260 class __pbase_type_info : public std::type_info 261 { 262 public: 263 unsigned int __flags; // Qualification of the target object. 264 const std::type_info* __pointee; // Type of pointed to object. 265 266 explicit 267 __pbase_type_info(const char* __n, int __quals, 268 const std::type_info* __type) 269 : std::type_info(__n), __flags(__quals), __pointee(__type) 270 { } 271 272 virtual 273 ~__pbase_type_info(); 274 275 // Implementation defined type. 276 enum __masks 277 { 278 __const_mask = 0x1, 279 __volatile_mask = 0x2, 280 __restrict_mask = 0x4, 281 __incomplete_mask = 0x8, 282 __incomplete_class_mask = 0x10 283 }; 284 285 protected: 286 __pbase_type_info(const __pbase_type_info&); 287 288 __pbase_type_info& 289 operator=(const __pbase_type_info&); 290 291 // Implementation defined member functions. 292 virtual bool 293 __do_catch(const std::type_info* __thr_type, void** __thr_obj, 294 unsigned int __outer) const; 295 296 inline virtual bool 297 __pointer_catch(const __pbase_type_info* __thr_type, void** __thr_obj, 298 unsigned __outer) const; 299 }; 300 301 // Type information for simple pointers. 302 class __pointer_type_info : public __pbase_type_info 303 { 304 public: 305 explicit 306 __pointer_type_info(const char* __n, int __quals, 307 const std::type_info* __type) 308 : __pbase_type_info (__n, __quals, __type) { } 309 310 311 virtual 312 ~__pointer_type_info(); 313 314 protected: 315 // Implementation defined member functions. 316 virtual bool 317 __is_pointer_p() const; 318 319 virtual bool 320 __pointer_catch(const __pbase_type_info* __thr_type, void** __thr_obj, 321 unsigned __outer) const; 322 }; 323 324 class __class_type_info; 325 326 // Type information for a pointer to member variable. 327 class __pointer_to_member_type_info : public __pbase_type_info 328 { 329 public: 330 __class_type_info* __context; // Class of the member. 331 332 explicit 333 __pointer_to_member_type_info(const char* __n, int __quals, 334 const std::type_info* __type, 335 __class_type_info* __klass) 336 : __pbase_type_info(__n, __quals, __type), __context(__klass) { } 337 338 virtual 339 ~__pointer_to_member_type_info(); 340 341 protected: 342 __pointer_to_member_type_info(const __pointer_to_member_type_info&); 343 344 __pointer_to_member_type_info& 345 operator=(const __pointer_to_member_type_info&); 346 347 // Implementation defined member function. 348 virtual bool 349 __pointer_catch(const __pbase_type_info* __thr_type, void** __thr_obj, 350 unsigned __outer) const; 351 }; 352 353 // Helper class for __vmi_class_type. 354 class __base_class_type_info 355 { 356 public: 357 const __class_type_info* __base_type; // Base class type. 358 #ifdef _GLIBCXX_LLP64 359 long long __offset_flags; // Offset and info. 360 #else 361 long __offset_flags; // Offset and info. 362 #endif 363 364 enum __offset_flags_masks 365 { 366 __virtual_mask = 0x1, 367 __public_mask = 0x2, 368 __hwm_bit = 2, 369 __offset_shift = 8 // Bits to shift offset. 370 }; 371 372 // Implementation defined member functions. 373 bool 374 __is_virtual_p() const 375 { return __offset_flags & __virtual_mask; } 376 377 bool 378 __is_public_p() const 379 { return __offset_flags & __public_mask; } 380 381 ptrdiff_t 382 __offset() const 383 { 384 // This shift, being of a signed type, is implementation 385 // defined. GCC implements such shifts as arithmetic, which is 386 // what we want. 387 return static_cast<ptrdiff_t>(__offset_flags) >> __offset_shift; 388 } 389 }; 390 391 // Type information for a class. 392 class __class_type_info : public std::type_info 393 { 394 public: 395 explicit 396 __class_type_info (const char *__n) : type_info(__n) { } 397 398 virtual 399 ~__class_type_info (); 400 401 // Implementation defined types. 402 // The type sub_kind tells us about how a base object is contained 403 // within a derived object. We often do this lazily, hence the 404 // UNKNOWN value. At other times we may use NOT_CONTAINED to mean 405 // not publicly contained. 406 enum __sub_kind 407 { 408 // We have no idea. 409 __unknown = 0, 410 411 // Not contained within us (in some circumstances this might 412 // mean not contained publicly) 413 __not_contained, 414 415 // Contained ambiguously. 416 __contained_ambig, 417 418 // Via a virtual path. 419 __contained_virtual_mask = __base_class_type_info::__virtual_mask, 420 421 // Via a public path. 422 __contained_public_mask = __base_class_type_info::__public_mask, 423 424 // Contained within us. 425 __contained_mask = 1 << __base_class_type_info::__hwm_bit, 426 427 __contained_private = __contained_mask, 428 __contained_public = __contained_mask | __contained_public_mask 429 }; 430 431 struct __upcast_result; 432 struct __dyncast_result; 433 434 protected: 435 // Implementation defined member functions. 436 virtual bool 437 __do_upcast(const __class_type_info* __dst_type, void**__obj_ptr) const; 438 439 virtual bool 440 __do_catch(const type_info* __thr_type, void** __thr_obj, 441 unsigned __outer) const; 442 443 public: 444 // Helper for upcast. See if DST is us, or one of our bases. 445 // Return false if not found, true if found. 446 virtual bool 447 __do_upcast(const __class_type_info* __dst, const void* __obj, 448 __upcast_result& __restrict __result) const; 449 450 // Indicate whether SRC_PTR of type SRC_TYPE is contained publicly 451 // within OBJ_PTR. OBJ_PTR points to a base object of our type, 452 // which is the destination type. SRC2DST indicates how SRC 453 // objects might be contained within this type. If SRC_PTR is one 454 // of our SRC_TYPE bases, indicate the virtuality. Returns 455 // not_contained for non containment or private containment. 456 inline __sub_kind 457 __find_public_src(ptrdiff_t __src2dst, const void* __obj_ptr, 458 const __class_type_info* __src_type, 459 const void* __src_ptr) const; 460 461 // Helper for dynamic cast. ACCESS_PATH gives the access from the 462 // most derived object to this base. DST_TYPE indicates the 463 // desired type we want. OBJ_PTR points to a base of our type 464 // within the complete object. SRC_TYPE indicates the static type 465 // started from and SRC_PTR points to that base within the most 466 // derived object. Fill in RESULT with what we find. Return true 467 // if we have located an ambiguous match. 468 virtual bool 469 __do_dyncast(ptrdiff_t __src2dst, __sub_kind __access_path, 470 const __class_type_info* __dst_type, const void* __obj_ptr, 471 const __class_type_info* __src_type, const void* __src_ptr, 472 __dyncast_result& __result) const; 473 474 // Helper for find_public_subobj. SRC2DST indicates how SRC_TYPE 475 // bases are inherited by the type started from -- which is not 476 // necessarily the current type. The current type will be a base 477 // of the destination type. OBJ_PTR points to the current base. 478 virtual __sub_kind 479 __do_find_public_src(ptrdiff_t __src2dst, const void* __obj_ptr, 480 const __class_type_info* __src_type, 481 const void* __src_ptr) const; 482 }; 483 484 // Type information for a class with a single non-virtual base. 485 class __si_class_type_info : public __class_type_info 486 { 487 public: 488 const __class_type_info* __base_type; 489 490 explicit 491 __si_class_type_info(const char *__n, const __class_type_info *__base) 492 : __class_type_info(__n), __base_type(__base) { } 493 494 virtual 495 ~__si_class_type_info(); 496 497 protected: 498 __si_class_type_info(const __si_class_type_info&); 499 500 __si_class_type_info& 501 operator=(const __si_class_type_info&); 502 503 // Implementation defined member functions. 504 virtual bool 505 __do_dyncast(ptrdiff_t __src2dst, __sub_kind __access_path, 506 const __class_type_info* __dst_type, const void* __obj_ptr, 507 const __class_type_info* __src_type, const void* __src_ptr, 508 __dyncast_result& __result) const; 509 510 virtual __sub_kind 511 __do_find_public_src(ptrdiff_t __src2dst, const void* __obj_ptr, 512 const __class_type_info* __src_type, 513 const void* __sub_ptr) const; 514 515 virtual bool 516 __do_upcast(const __class_type_info*__dst, const void*__obj, 517 __upcast_result& __restrict __result) const; 518 }; 519 520 // Type information for a class with multiple and/or virtual bases. 521 class __vmi_class_type_info : public __class_type_info 522 { 523 public: 524 unsigned int __flags; // Details about the class hierarchy. 525 unsigned int __base_count; // Number of direct bases. 526 527 // The array of bases uses the trailing array struct hack so this 528 // class is not constructable with a normal constructor. It is 529 // internally generated by the compiler. 530 __base_class_type_info __base_info[1]; // Array of bases. 531 532 explicit 533 __vmi_class_type_info(const char* __n, int ___flags) 534 : __class_type_info(__n), __flags(___flags), __base_count(0) { } 535 536 virtual 537 ~__vmi_class_type_info(); 538 539 // Implementation defined types. 540 enum __flags_masks 541 { 542 __non_diamond_repeat_mask = 0x1, // Distinct instance of repeated base. 543 __diamond_shaped_mask = 0x2, // Diamond shaped multiple inheritance. 544 __flags_unknown_mask = 0x10 545 }; 546 547 protected: 548 // Implementation defined member functions. 549 virtual bool 550 __do_dyncast(ptrdiff_t __src2dst, __sub_kind __access_path, 551 const __class_type_info* __dst_type, const void* __obj_ptr, 552 const __class_type_info* __src_type, const void* __src_ptr, 553 __dyncast_result& __result) const; 554 555 virtual __sub_kind 556 __do_find_public_src(ptrdiff_t __src2dst, const void* __obj_ptr, 557 const __class_type_info* __src_type, 558 const void* __src_ptr) const; 559 560 virtual bool 561 __do_upcast(const __class_type_info* __dst, const void* __obj, 562 __upcast_result& __restrict __result) const; 563 }; 564 565 // Exception handling forward declarations. 566 struct __cxa_exception; 567 struct __cxa_refcounted_exception; 568 struct __cxa_dependent_exception; 569 struct __cxa_eh_globals; 570 571 extern "C" 572 { 573 // Dynamic cast runtime. 574 575 // src2dst has the following possible values 576 // >-1: src_type is a unique public non-virtual base of dst_type 577 // dst_ptr + src2dst == src_ptr 578 // -1: unspecified relationship 579 // -2: src_type is not a public base of dst_type 580 // -3: src_type is a multiple public non-virtual base of dst_type 581 void* 582 __dynamic_cast(const void* __src_ptr, // Starting object. 583 const __class_type_info* __src_type, // Static type of object. 584 const __class_type_info* __dst_type, // Desired target type. 585 ptrdiff_t __src2dst); // How src and dst are related. 586 587 588 // Exception handling runtime. 589 590 // The __cxa_eh_globals for the current thread can be obtained by using 591 // either of the following functions. The "fast" version assumes at least 592 // one prior call of __cxa_get_globals has been made from the current 593 // thread, so no initialization is necessary. 594 __cxa_eh_globals* 595 __cxa_get_globals() _GLIBCXX_NOTHROW __attribute__ ((__const__)); 596 597 __cxa_eh_globals* 598 __cxa_get_globals_fast() _GLIBCXX_NOTHROW __attribute__ ((__const__)); 599 600 // Allocate memory for the primary exception plus the thrown object. 601 void* 602 __cxa_allocate_exception(size_t) _GLIBCXX_NOTHROW; 603 604 // Free the space allocated for the primary exception. 605 void 606 __cxa_free_exception(void*) _GLIBCXX_NOTHROW; 607 608 // Throw the exception. 609 void 610 __cxa_throw(void*, std::type_info*, void (_GLIBCXX_CDTOR_CALLABI *) (void *)) 611 __attribute__((__noreturn__)); 612 613 // Used to implement exception handlers. 614 void* 615 __cxa_get_exception_ptr(void*) _GLIBCXX_NOTHROW __attribute__ ((__pure__)); 616 617 void* 618 __cxa_begin_catch(void*) _GLIBCXX_NOTHROW; 619 620 void 621 __cxa_end_catch(); 622 623 void 624 __cxa_rethrow() __attribute__((__noreturn__)); 625 626 // Returns the type_info for the currently handled exception [15.3/8], or 627 // null if there is none. 628 std::type_info* 629 __cxa_current_exception_type() _GLIBCXX_NOTHROW __attribute__ ((__pure__)); 630 631 // GNU Extensions. 632 633 // Allocate memory for a dependent exception. 634 __cxa_dependent_exception* 635 __cxa_allocate_dependent_exception() _GLIBCXX_NOTHROW; 636 637 // Free the space allocated for the dependent exception. 638 void 639 __cxa_free_dependent_exception(__cxa_dependent_exception*) _GLIBCXX_NOTHROW; 640 641 } // extern "C" 642 643 // A magic placeholder class that can be caught by reference 644 // to recognize foreign exceptions. 645 class __foreign_exception 646 { 647 virtual ~__foreign_exception() throw(); 648 virtual void __pure_dummy() = 0; // prevent catch by value 649 }; 650 651 } // namespace __cxxabiv1 652 653 /** @namespace abi 654 * @brief The cross-vendor C++ Application Binary Interface. A 655 * namespace alias to __cxxabiv1, but user programs should use the 656 * alias 'abi'. 657 * 658 * A brief overview of an ABI is given in the libstdc++ FAQ, question 659 * 5.8 (you may have a copy of the FAQ locally, or you can view the online 660 * version at http://gcc.gnu.org/onlinedocs/libstdc++/faq.html#5_8 ). 661 * 662 * GCC subscribes to a cross-vendor ABI for C++, sometimes 663 * called the IA64 ABI because it happens to be the native ABI for that 664 * platform. It is summarized at http://www.codesourcery.com/cxx-abi/ 665 * along with the current specification. 666 * 667 * For users of GCC greater than or equal to 3.x, entry points are 668 * available in <cxxabi.h>, which notes, <em>'It is not normally 669 * necessary for user programs to include this header, or use the 670 * entry points directly. However, this header is available should 671 * that be needed.'</em> 672 */ 673 namespace abi = __cxxabiv1; 674 675 namespace __gnu_cxx 676 { 677 /** 678 * @brief Exception thrown by __cxa_guard_acquire. 679 * @ingroup exceptions 680 * 681 * 6.7[stmt.dcl]/4: If control re-enters the declaration (recursively) 682 * while the object is being initialized, the behavior is undefined. 683 * 684 * Since we already have a library function to handle locking, we might 685 * as well check for this situation and throw an exception. 686 * We use the second byte of the guard variable to remember that we're 687 * in the middle of an initialization. 688 */ 689 class recursive_init_error: public std::exception 690 { 691 public: 692 recursive_init_error() throw() { } 693 virtual ~recursive_init_error() throw (); 694 }; 695 } 696 #endif // __cplusplus 697 698 #pragma GCC visibility pop 699 700 #endif // __CXXABI_H 701