1 //===-- Debug.cpp - An easy way to add debug output to your code ----------===// 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 handle 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 in release mode, the -debug-* options and all code in DEBUG() 22 // statements disappears, so it does not effect the runtime of the code. 23 // 24 //===----------------------------------------------------------------------===// 25 26 #include "llvm/Support/CommandLine.h" 27 #include "llvm/Support/Debug.h" 28 using namespace llvm; 29 30 // All Debug.h functionality is a no-op in NDEBUG mode. 31 #ifndef NDEBUG 32 bool llvm::DebugFlag; // DebugFlag - Exported boolean set by the -debug option 33 34 // -debug - Command line option to enable the DEBUG statements in the passes. 35 // This flag may only be enabled in debug builds. 36 static cl::opt<bool, true> 37 Debug("debug", cl::desc("Enable debug output"), cl::Hidden, 38 cl::location(DebugFlag)); 39 40 static std::string CurrentDebugType; 41 static struct DebugOnlyOpt { 42 void operator=(const std::string &Val) const { 43 DebugFlag |= !Val.empty(); 44 CurrentDebugType = Val; 45 } 46 } DebugOnlyOptLoc; 47 48 static cl::opt<DebugOnlyOpt, true, cl::parser<std::string> > 49 DebugOnly("debug-only", cl::desc("Enable a specific type of debug output"), 50 cl::Hidden, cl::value_desc("debug string"), 51 cl::location(DebugOnlyOptLoc), cl::ValueRequired); 52 53 // isCurrentDebugType - Return true if the specified string is the debug type 54 // specified on the command line, or if none was specified on the command line 55 // with the -debug-only=X option. 56 // 57 bool llvm::isCurrentDebugType(const char *DebugType) { 58 return CurrentDebugType.empty() || DebugType == CurrentDebugType; 59 } 60 61 /// SetCurrentDebugType - Set the current debug type, as if the -debug-only=X 62 /// option were specified. Note that DebugFlag also needs to be set to true for 63 /// debug output to be produced. 64 /// 65 void llvm::SetCurrentDebugType(const char *Type) { 66 CurrentDebugType = Type; 67 } 68 69 #else 70 // Avoid "has no symbols" warning. 71 namespace llvm { 72 int Debug_dummy = 0; 73 } 74 #endif 75