1 //===- llvm/Support/Debug.h - Easy way to add debug output ------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
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.
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
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.
24 //===----------------------------------------------------------------------===//
26 #ifndef LLVM_SUPPORT_DEBUG_H
27 #define LLVM_SUPPORT_DEBUG_H
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.
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.
44 extern bool DebugFlag;
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.
50 bool isCurrentDebugType(const char *Type);
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.
56 void SetCurrentDebugType(const char *Type);
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:
63 /// DEBUG_WITH_TYPE("bitset", dbgs() << "Bitset contains: " << Bitset << "\n");
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; } \
72 #define isCurrentDebugType(X) (false)
73 #define SetCurrentDebugType(X)
74 #define DEBUG_WITH_TYPE(TYPE, X) do { } while (0)
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
83 extern bool EnableDebugBuffering;
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";
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:
95 // DEBUG(dbgs() << "Bitset contains: " << Bitset << "\n");
97 #define DEBUG(X) DEBUG_WITH_TYPE(DEBUG_TYPE, X)
99 } // End llvm namespace