1 //===- llvm/Support/Debug.h - Easy way to add debug output ------*- C++ -*-===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // This file implements a handy way of adding debugging information to your 11 // code, without it being enabled all of the time, and without having to add 12 // command line options to enable it. 13 // 14 // In particular, just wrap your code with the DEBUG() macro, and it will be 15 // enabled automatically if you specify '-debug' on the command-line. 16 // Alternatively, you can also use the SET_DEBUG_TYPE("foo") macro to specify 17 // that your debug code belongs to class "foo". Then, on the command line, you 18 // can specify '-debug-only=foo' to enable JUST the debug information for the 19 // foo class. 20 // 21 // When compiling without assertions, the -debug-* options and all code in 22 // DEBUG() statements disappears, so it does not effect the runtime of the code. 23 // 24 //===----------------------------------------------------------------------===// 25 26 #ifndef LLVM_SUPPORT_DEBUG_H 27 #define LLVM_SUPPORT_DEBUG_H 28 29 namespace llvm { 30 31 class raw_ostream; 32 33 /// DEBUG_TYPE macro - Files can specify a DEBUG_TYPE as a string, which causes 34 /// all of their DEBUG statements to be activatable with -debug-only=thatstring. 35 #ifndef DEBUG_TYPE 36 #define DEBUG_TYPE "" 37 #endif 38 39 #ifndef NDEBUG 40 /// DebugFlag - This boolean is set to true if the '-debug' command line option 41 /// is specified. This should probably not be referenced directly, instead, use 42 /// the DEBUG macro below. 43 /// 44 extern bool DebugFlag; 45 46 /// isCurrentDebugType - Return true if the specified string is the debug type 47 /// specified on the command line, or if none was specified on the command line 48 /// with the -debug-only=X option. 49 /// 50 bool isCurrentDebugType(const char *Type); 51 52 /// SetCurrentDebugType - Set the current debug type, as if the -debug-only=X 53 /// option were specified. Note that DebugFlag also needs to be set to true for 54 /// debug output to be produced. 55 /// 56 void SetCurrentDebugType(const char *Type); 57 58 /// DEBUG_WITH_TYPE macro - This macro should be used by passes to emit debug 59 /// information. In the '-debug' option is specified on the commandline, and if 60 /// this is a debug build, then the code specified as the option to the macro 61 /// will be executed. Otherwise it will not be. Example: 62 /// 63 /// DEBUG_WITH_TYPE("bitset", dbgs() << "Bitset contains: " << Bitset << "\n"); 64 /// 65 /// This will emit the debug information if -debug is present, and -debug-only 66 /// is not specified, or is specified as "bitset". 67 #define DEBUG_WITH_TYPE(TYPE, X) \ 68 do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType(TYPE)) { X; } \ 69 } while (0) 70 71 #else 72 #define isCurrentDebugType(X) (false) 73 #define SetCurrentDebugType(X) 74 #define DEBUG_WITH_TYPE(TYPE, X) do { } while (0) 75 #endif 76 77 /// EnableDebugBuffering - This defaults to false. If true, the debug 78 /// stream will install signal handlers to dump any buffered debug 79 /// output. It allows clients to selectively allow the debug stream 80 /// to install signal handlers if they are certain there will be no 81 /// conflict. 82 /// 83 extern bool EnableDebugBuffering; 84 85 /// dbgs() - This returns a reference to a raw_ostream for debugging 86 /// messages. If debugging is disabled it returns errs(). Use it 87 /// like: dbgs() << "foo" << "bar"; 88 raw_ostream &dbgs(); 89 90 // DEBUG macro - This macro should be used by passes to emit debug information. 91 // In the '-debug' option is specified on the commandline, and if this is a 92 // debug build, then the code specified as the option to the macro will be 93 // executed. Otherwise it will not be. Example: 94 // 95 // DEBUG(dbgs() << "Bitset contains: " << Bitset << "\n"); 96 // 97 #define DEBUG(X) DEBUG_WITH_TYPE(DEBUG_TYPE, X) 98 99 } // End llvm namespace 100 101 #endif 102