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 29namespace llvm { 30 31class 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/// 44extern 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/// 50bool 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/// 56void 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/// 83extern 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"; 88raw_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