1b0094c2404d0f826aa736bdb7d4d2fba65ad50b4Chris Lattner//===- llvm/Support/ErrorHandling.h - Fatal error handling ------*- C++ -*-===// 231e2466f159a887fed9139067a676f65adf2a8c3Torok Edwin// 331e2466f159a887fed9139067a676f65adf2a8c3Torok Edwin// The LLVM Compiler Infrastructure 431e2466f159a887fed9139067a676f65adf2a8c3Torok Edwin// 531e2466f159a887fed9139067a676f65adf2a8c3Torok Edwin// This file is distributed under the University of Illinois Open Source 631e2466f159a887fed9139067a676f65adf2a8c3Torok Edwin// License. See LICENSE.TXT for details. 731e2466f159a887fed9139067a676f65adf2a8c3Torok Edwin// 831e2466f159a887fed9139067a676f65adf2a8c3Torok Edwin//===----------------------------------------------------------------------===// 931e2466f159a887fed9139067a676f65adf2a8c3Torok Edwin// 10b0094c2404d0f826aa736bdb7d4d2fba65ad50b4Chris Lattner// This file defines an API used to indicate fatal error conditions. Non-fatal 11b0094c2404d0f826aa736bdb7d4d2fba65ad50b4Chris Lattner// errors (most of them) should be handled through LLVMContext. 1231e2466f159a887fed9139067a676f65adf2a8c3Torok Edwin// 1331e2466f159a887fed9139067a676f65adf2a8c3Torok Edwin//===----------------------------------------------------------------------===// 1431e2466f159a887fed9139067a676f65adf2a8c3Torok Edwin 1531e2466f159a887fed9139067a676f65adf2a8c3Torok Edwin#ifndef LLVM_SUPPORT_ERRORHANDLING_H 1631e2466f159a887fed9139067a676f65adf2a8c3Torok Edwin#define LLVM_SUPPORT_ERRORHANDLING_H 1731e2466f159a887fed9139067a676f65adf2a8c3Torok Edwin 18afd693cff38ea76188f8f895c75fdf24c90c606aDaniel Dunbar#include "llvm/ADT/StringRef.h" 19255f89faee13dc491cb64fbeae3c763e7e2ea4e6Chandler Carruth#include "llvm/Support/Compiler.h" 2013223c98f2fa63c7d718287313c328a813509839Alisdair Meredith#include <string> 2131e2466f159a887fed9139067a676f65adf2a8c3Torok Edwin 2231e2466f159a887fed9139067a676f65adf2a8c3Torok Edwinnamespace llvm { 2382a29b6a02324e65847ed99bae84dafb2755ea32Daniel Dunbar class Twine; 2482a29b6a02324e65847ed99bae84dafb2755ea32Daniel Dunbar 25b6017b03dab80e1e7bfeec4e7debff0fefa9563eChris Lattner /// An error handler callback. 26b0094c2404d0f826aa736bdb7d4d2fba65ad50b4Chris Lattner typedef void (*fatal_error_handler_t)(void *user_data, 27ce945578ee190cefee0cdd987c1c287d04b8536aChad Rosier const std::string& reason, 28ce945578ee190cefee0cdd987c1c287d04b8536aChad Rosier bool gen_crash_diag); 2931e2466f159a887fed9139067a676f65adf2a8c3Torok Edwin 30b0094c2404d0f826aa736bdb7d4d2fba65ad50b4Chris Lattner /// install_fatal_error_handler - Installs a new error handler to be used 31ca15f3d6d6c29e9cc75225730270e9ef85834a22Daniel Dunbar /// whenever a serious (non-recoverable) error is encountered by LLVM. 32ca15f3d6d6c29e9cc75225730270e9ef85834a22Daniel Dunbar /// 33b6017b03dab80e1e7bfeec4e7debff0fefa9563eChris Lattner /// If you are using llvm_start_multithreaded, you should register the handler 34b6017b03dab80e1e7bfeec4e7debff0fefa9563eChris Lattner /// before doing that. 35b6017b03dab80e1e7bfeec4e7debff0fefa9563eChris Lattner /// 36b6017b03dab80e1e7bfeec4e7debff0fefa9563eChris Lattner /// If no error handler is installed the default is to print the error message 37ca15f3d6d6c29e9cc75225730270e9ef85834a22Daniel Dunbar /// to stderr, and call exit(1). If an error handler is installed then it is 38ca15f3d6d6c29e9cc75225730270e9ef85834a22Daniel Dunbar /// the handler's responsibility to log the message, it will no longer be 39ca15f3d6d6c29e9cc75225730270e9ef85834a22Daniel Dunbar /// printed to stderr. If the error handler returns, then exit(1) will be 40ca15f3d6d6c29e9cc75225730270e9ef85834a22Daniel Dunbar /// called. 41ca15f3d6d6c29e9cc75225730270e9ef85834a22Daniel Dunbar /// 42583b6dbcc586359e6ea7c3e4ac46bdb708779dceDan Gohman /// It is dangerous to naively use an error handler which throws an exception. 43583b6dbcc586359e6ea7c3e4ac46bdb708779dceDan Gohman /// Even though some applications desire to gracefully recover from arbitrary 44583b6dbcc586359e6ea7c3e4ac46bdb708779dceDan Gohman /// faults, blindly throwing exceptions through unfamiliar code isn't a way to 45583b6dbcc586359e6ea7c3e4ac46bdb708779dceDan Gohman /// achieve this. 46583b6dbcc586359e6ea7c3e4ac46bdb708779dceDan Gohman /// 47ca15f3d6d6c29e9cc75225730270e9ef85834a22Daniel Dunbar /// \param user_data - An argument which will be passed to the install error 48ca15f3d6d6c29e9cc75225730270e9ef85834a22Daniel Dunbar /// handler. 49b0094c2404d0f826aa736bdb7d4d2fba65ad50b4Chris Lattner void install_fatal_error_handler(fatal_error_handler_t handler, 50b0094c2404d0f826aa736bdb7d4d2fba65ad50b4Chris Lattner void *user_data = 0); 5131e2466f159a887fed9139067a676f65adf2a8c3Torok Edwin 52b6017b03dab80e1e7bfeec4e7debff0fefa9563eChris Lattner /// Restores default error handling behaviour. 53b6017b03dab80e1e7bfeec4e7debff0fefa9563eChris Lattner /// This must not be called between llvm_start_multithreaded() and 54b6017b03dab80e1e7bfeec4e7debff0fefa9563eChris Lattner /// llvm_stop_multithreaded(). 55b0094c2404d0f826aa736bdb7d4d2fba65ad50b4Chris Lattner void remove_fatal_error_handler(); 5631e2466f159a887fed9139067a676f65adf2a8c3Torok Edwin 57e16068240e21650becf9b47a4dc2284531397696Dan Gohman /// ScopedFatalErrorHandler - This is a simple helper class which just 58e16068240e21650becf9b47a4dc2284531397696Dan Gohman /// calls install_fatal_error_handler in its constructor and 59e16068240e21650becf9b47a4dc2284531397696Dan Gohman /// remove_fatal_error_handler in its destructor. 60e16068240e21650becf9b47a4dc2284531397696Dan Gohman struct ScopedFatalErrorHandler { 61e16068240e21650becf9b47a4dc2284531397696Dan Gohman explicit ScopedFatalErrorHandler(fatal_error_handler_t handler, 62e16068240e21650becf9b47a4dc2284531397696Dan Gohman void *user_data = 0) { 63e16068240e21650becf9b47a4dc2284531397696Dan Gohman install_fatal_error_handler(handler, user_data); 64e16068240e21650becf9b47a4dc2284531397696Dan Gohman } 65e16068240e21650becf9b47a4dc2284531397696Dan Gohman 66e16068240e21650becf9b47a4dc2284531397696Dan Gohman ~ScopedFatalErrorHandler() { remove_fatal_error_handler(); } 67e16068240e21650becf9b47a4dc2284531397696Dan Gohman }; 68e16068240e21650becf9b47a4dc2284531397696Dan Gohman 69583b6dbcc586359e6ea7c3e4ac46bdb708779dceDan Gohman /// Reports a serious error, calling any installed error handler. These 70583b6dbcc586359e6ea7c3e4ac46bdb708779dceDan Gohman /// functions are intended to be used for error conditions which are outside 71583b6dbcc586359e6ea7c3e4ac46bdb708779dceDan Gohman /// the control of the compiler (I/O errors, invalid user input, etc.) 72583b6dbcc586359e6ea7c3e4ac46bdb708779dceDan Gohman /// 73b6017b03dab80e1e7bfeec4e7debff0fefa9563eChris Lattner /// If no error handler is installed the default is to print the message to 7497c8c51f075ff49b1f67f6d7d31969212d72512bTorok Edwin /// standard error, followed by a newline. 753b30a2bdcaf6a63690309c0df3dae23defb14005Torok Edwin /// After the error handler is called this function will call exit(1), it 763b30a2bdcaf6a63690309c0df3dae23defb14005Torok Edwin /// does not return. 77ce945578ee190cefee0cdd987c1c287d04b8536aChad Rosier LLVM_ATTRIBUTE_NORETURN void report_fatal_error(const char *reason, 78ce945578ee190cefee0cdd987c1c287d04b8536aChad Rosier bool gen_crash_diag = true); 79ce945578ee190cefee0cdd987c1c287d04b8536aChad Rosier LLVM_ATTRIBUTE_NORETURN void report_fatal_error(const std::string &reason, 80ce945578ee190cefee0cdd987c1c287d04b8536aChad Rosier bool gen_crash_diag = true); 81ce945578ee190cefee0cdd987c1c287d04b8536aChad Rosier LLVM_ATTRIBUTE_NORETURN void report_fatal_error(StringRef reason, 82ce945578ee190cefee0cdd987c1c287d04b8536aChad Rosier bool gen_crash_diag = true); 83ce945578ee190cefee0cdd987c1c287d04b8536aChad Rosier LLVM_ATTRIBUTE_NORETURN void report_fatal_error(const Twine &reason, 84ce945578ee190cefee0cdd987c1c287d04b8536aChad Rosier bool gen_crash_diag = true); 8531e2466f159a887fed9139067a676f65adf2a8c3Torok Edwin 8697c8c51f075ff49b1f67f6d7d31969212d72512bTorok Edwin /// This function calls abort(), and prints the optional message to stderr. 87c23197a26f34f559ea9797de51e187087c039c42Torok Edwin /// Use the llvm_unreachable macro (that adds location info), instead of 88c23197a26f34f559ea9797de51e187087c039c42Torok Edwin /// calling this function directly. 8919e57025d458d3cb50804fd821fd89b868a819bdChandler Carruth LLVM_ATTRIBUTE_NORETURN void llvm_unreachable_internal(const char *msg=0, 9019e57025d458d3cb50804fd821fd89b868a819bdChandler Carruth const char *file=0, 9119e57025d458d3cb50804fd821fd89b868a819bdChandler Carruth unsigned line=0); 9231e2466f159a887fed9139067a676f65adf2a8c3Torok Edwin} 9331e2466f159a887fed9139067a676f65adf2a8c3Torok Edwin 94b121bfcc22660b1bdfb1183b191b6516988bcaf5John McCall/// Marks that the current location is not supposed to be reachable. 95b121bfcc22660b1bdfb1183b191b6516988bcaf5John McCall/// In !NDEBUG builds, prints the message and location info to stderr. 96b121bfcc22660b1bdfb1183b191b6516988bcaf5John McCall/// In NDEBUG builds, becomes an optimizer hint that the current location 97b121bfcc22660b1bdfb1183b191b6516988bcaf5John McCall/// is not supposed to be reachable. On compilers that don't support 98b121bfcc22660b1bdfb1183b191b6516988bcaf5John McCall/// such hints, prints a reduced message instead. 99583b6dbcc586359e6ea7c3e4ac46bdb708779dceDan Gohman/// 100b121bfcc22660b1bdfb1183b191b6516988bcaf5John McCall/// Use this instead of assert(0). It conveys intent more clearly and 101b121bfcc22660b1bdfb1183b191b6516988bcaf5John McCall/// allows compilers to omit some unnecessary code. 102dac237e18209b697a8ba122d0ddd9cad4dfba1f8Torok Edwin#ifndef NDEBUG 10366b856683fb67796aa77e52d676c4739e8e47d6dJeffrey Yasskin#define llvm_unreachable(msg) \ 10466b856683fb67796aa77e52d676c4739e8e47d6dJeffrey Yasskin ::llvm::llvm_unreachable_internal(msg, __FILE__, __LINE__) 105b121bfcc22660b1bdfb1183b191b6516988bcaf5John McCall#elif defined(LLVM_BUILTIN_UNREACHABLE) 1062f9a9ed785416a7350f30141fcc405b69a1b9d5dJohn McCall#define llvm_unreachable(msg) LLVM_BUILTIN_UNREACHABLE 107b121bfcc22660b1bdfb1183b191b6516988bcaf5John McCall#else 108b121bfcc22660b1bdfb1183b191b6516988bcaf5John McCall#define llvm_unreachable(msg) ::llvm::llvm_unreachable_internal() 109dac237e18209b697a8ba122d0ddd9cad4dfba1f8Torok Edwin#endif 110ab7c09b6b6f4516a631fd6788918c237c83939afTorok Edwin 11131e2466f159a887fed9139067a676f65adf2a8c3Torok Edwin#endif 112