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 define the DEBUG_TYPE macro to "foo" specify 17// that your debug code belongs to class "foo". Be careful that you only do 18// this after including Debug.h and not around any #include of headers. Headers 19// should define and undef the macro acround the code that needs to use the 20// DEBUG() macro. Then, on the command line, you can specify '-debug-only=foo' 21// to enable JUST the debug information for the foo class. 22// 23// When compiling without assertions, the -debug-* options and all code in 24// DEBUG() statements disappears, so it does not affect the runtime of the code. 25// 26//===----------------------------------------------------------------------===// 27 28#ifndef LLVM_SUPPORT_DEBUG_H 29#define LLVM_SUPPORT_DEBUG_H 30 31#include "llvm/Support/raw_ostream.h" 32 33namespace llvm { 34 35#ifndef NDEBUG 36/// DebugFlag - This boolean is set to true if the '-debug' command line option 37/// is specified. This should probably not be referenced directly, instead, use 38/// the DEBUG macro below. 39/// 40extern bool DebugFlag; 41 42/// isCurrentDebugType - Return true if the specified string is the debug type 43/// specified on the command line, or if none was specified on the command line 44/// with the -debug-only=X option. 45/// 46bool isCurrentDebugType(const char *Type); 47 48/// setCurrentDebugType - Set the current debug type, as if the -debug-only=X 49/// option were specified. Note that DebugFlag also needs to be set to true for 50/// debug output to be produced. 51/// 52void setCurrentDebugType(const char *Type); 53 54/// DEBUG_WITH_TYPE macro - This macro should be used by passes to emit debug 55/// information. In the '-debug' option is specified on the commandline, and if 56/// this is a debug build, then the code specified as the option to the macro 57/// will be executed. Otherwise it will not be. Example: 58/// 59/// DEBUG_WITH_TYPE("bitset", dbgs() << "Bitset contains: " << Bitset << "\n"); 60/// 61/// This will emit the debug information if -debug is present, and -debug-only 62/// is not specified, or is specified as "bitset". 63#define DEBUG_WITH_TYPE(TYPE, X) \ 64 do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType(TYPE)) { X; } \ 65 } while (0) 66 67#else 68#define isCurrentDebugType(X) (false) 69#define setCurrentDebugType(X) 70#define DEBUG_WITH_TYPE(TYPE, X) do { } while (0) 71#endif 72 73/// EnableDebugBuffering - This defaults to false. If true, the debug 74/// stream will install signal handlers to dump any buffered debug 75/// output. It allows clients to selectively allow the debug stream 76/// to install signal handlers if they are certain there will be no 77/// conflict. 78/// 79extern bool EnableDebugBuffering; 80 81/// dbgs() - This returns a reference to a raw_ostream for debugging 82/// messages. If debugging is disabled it returns errs(). Use it 83/// like: dbgs() << "foo" << "bar"; 84raw_ostream &dbgs(); 85 86// DEBUG macro - This macro should be used by passes to emit debug information. 87// In the '-debug' option is specified on the commandline, and if this is a 88// debug build, then the code specified as the option to the macro will be 89// executed. Otherwise it will not be. Example: 90// 91// DEBUG(dbgs() << "Bitset contains: " << Bitset << "\n"); 92// 93#define DEBUG(X) DEBUG_WITH_TYPE(DEBUG_TYPE, X) 94 95} // End llvm namespace 96 97#endif 98