LLVM  9.0.0svn
Debug.h
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1 //===- llvm/Support/Debug.h - Easy way to add debug output ------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file implements a handy way of adding debugging information to your
10 // code, without it being enabled all of the time, and without having to add
11 // command line options to enable it.
12 //
13 // In particular, just wrap your code with the LLVM_DEBUG() macro, and it will
14 // be enabled automatically if you specify '-debug' on the command-line.
15 // LLVM_DEBUG() requires the DEBUG_TYPE macro to be defined. Set it to "foo"
16 // specify that your debug code belongs to class "foo". Be careful that you only
17 // do this after including Debug.h and not around any #include of headers.
18 // Headers should define and undef the macro acround the code that needs to use
19 // the LLVM_DEBUG() macro. Then, on the command line, you can specify
20 // '-debug-only=foo' to enable JUST the debug information for the foo class.
21 //
22 // When compiling without assertions, the -debug-* options and all code in
23 // LLVM_DEBUG() statements disappears, so it does not affect the runtime of the
24 // code.
25 //
26 //===----------------------------------------------------------------------===//
27 
28 #ifndef LLVM_SUPPORT_DEBUG_H
29 #define LLVM_SUPPORT_DEBUG_H
30 
31 namespace llvm {
32 
33 class raw_ostream;
34 
35 #ifndef NDEBUG
36 
37 /// isCurrentDebugType - Return true if the specified string is the debug type
38 /// specified on the command line, or if none was specified on the command line
39 /// with the -debug-only=X option.
40 ///
41 bool isCurrentDebugType(const char *Type);
42 
43 /// setCurrentDebugType - Set the current debug type, as if the -debug-only=X
44 /// option were specified. Note that DebugFlag also needs to be set to true for
45 /// debug output to be produced.
46 ///
47 void setCurrentDebugType(const char *Type);
48 
49 /// setCurrentDebugTypes - Set the current debug type, as if the
50 /// -debug-only=X,Y,Z option were specified. Note that DebugFlag
51 /// also needs to be set to true for debug output to be produced.
52 ///
53 void setCurrentDebugTypes(const char **Types, unsigned Count);
54 
55 /// DEBUG_WITH_TYPE macro - This macro should be used by passes to emit debug
56 /// information. In the '-debug' option is specified on the commandline, and if
57 /// this is a debug build, then the code specified as the option to the macro
58 /// will be executed. Otherwise it will not be. Example:
59 ///
60 /// DEBUG_WITH_TYPE("bitset", dbgs() << "Bitset contains: " << Bitset << "\n");
61 ///
62 /// This will emit the debug information if -debug is present, and -debug-only
63 /// is not specified, or is specified as "bitset".
64 #define DEBUG_WITH_TYPE(TYPE, X) \
65  do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType(TYPE)) { X; } \
66  } while (false)
67 
68 #else
69 #define isCurrentDebugType(X) (false)
70 #define setCurrentDebugType(X)
71 #define setCurrentDebugTypes(X, N)
72 #define DEBUG_WITH_TYPE(TYPE, X) do { } while (false)
73 #endif
74 
75 /// This boolean is set to true if the '-debug' command line option
76 /// is specified. This should probably not be referenced directly, instead, use
77 /// the DEBUG macro below.
78 ///
79 extern bool DebugFlag;
80 
81 /// \name Verification flags.
82 ///
83 /// These flags turns on/off that are expensive and are turned off by default,
84 /// unless macro EXPENSIVE_CHECKS is defined. The flags allow selectively
85 /// turning the checks on without need to recompile.
86 /// \{
87 
88 /// Enables verification of dominator trees.
89 ///
90 extern bool VerifyDomInfo;
91 
92 /// Enables verification of loop info.
93 ///
94 extern bool VerifyLoopInfo;
95 
96 /// Enables verification of MemorySSA.
97 ///
98 extern bool VerifyMemorySSA;
99 
100 ///\}
101 
102 /// EnableDebugBuffering - This defaults to false. If true, the debug
103 /// stream will install signal handlers to dump any buffered debug
104 /// output. It allows clients to selectively allow the debug stream
105 /// to install signal handlers if they are certain there will be no
106 /// conflict.
107 ///
108 extern bool EnableDebugBuffering;
109 
110 /// dbgs() - This returns a reference to a raw_ostream for debugging
111 /// messages. If debugging is disabled it returns errs(). Use it
112 /// like: dbgs() << "foo" << "bar";
113 raw_ostream &dbgs();
114 
115 // DEBUG macro - This macro should be used by passes to emit debug information.
116 // In the '-debug' option is specified on the commandline, and if this is a
117 // debug build, then the code specified as the option to the macro will be
118 // executed. Otherwise it will not be. Example:
119 //
120 // LLVM_DEBUG(dbgs() << "Bitset contains: " << Bitset << "\n");
121 //
122 #define LLVM_DEBUG(X) DEBUG_WITH_TYPE(DEBUG_TYPE, X)
123 
124 } // end namespace llvm
125 
126 #endif // LLVM_SUPPORT_DEBUG_H
Type
MessagePack types as defined in the standard, with the exception of Integer being divided into a sign...
Definition: MsgPackReader.h:48
bool VerifyMemorySSA
Enables verification of MemorySSA.
Definition: MemorySSA.cpp:82
This class represents lattice values for constants.
Definition: AllocatorList.h:23
void setCurrentDebugType(const char *Type)
setCurrentDebugType - Set the current debug type, as if the -debug-only=X option were specified...
Definition: Debug.cpp:68
bool VerifyDomInfo
Enables verification of dominator trees.
Definition: Dominators.cpp:31
bool VerifyLoopInfo
Enables verification of loop info.
Definition: LoopInfo.cpp:49
raw_ostream & dbgs()
dbgs() - This returns a reference to a raw_ostream for debugging messages.
Definition: Debug.cpp:132
bool EnableDebugBuffering
EnableDebugBuffering - This defaults to false.
Definition: Debug.cpp:165
bool DebugFlag
This boolean is set to true if the &#39;-debug&#39; command line option is specified.
Definition: Debug.cpp:43
bool isCurrentDebugType(const char *Type)
isCurrentDebugType - Return true if the specified string is the debug type specified on the command l...
Definition: Debug.cpp:50
void setCurrentDebugTypes(const char **Types, unsigned Count)
setCurrentDebugTypes - Set the current debug type, as if the -debug-only=X,Y,Z option were specified...
Definition: Debug.cpp:72