1 //===- llvm/PassSupport.h - Pass Support code -------------------*- 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 defines stuff that is used to define and "use" Passes.  This file
11 // is automatically #included by Pass.h, so:
12 //
13 //           NO .CPP FILES SHOULD INCLUDE THIS FILE DIRECTLY
14 //
15 // Instead, #include Pass.h.
16 //
17 // This file defines Pass registration code and classes used for it.
18 //
19 //===----------------------------------------------------------------------===//
20 
21 #ifndef LLVM_PASSSUPPORT_H
22 #define LLVM_PASSSUPPORT_H
23 
24 #include "Pass.h"
25 #include "llvm/InitializePasses.h"
26 #include "llvm/PassInfo.h"
27 #include "llvm/PassRegistry.h"
28 #include "llvm/Support/Atomic.h"
29 #include "llvm/Support/Valgrind.h"
30 #include <vector>
31 
32 namespace llvm {
33 
34 class TargetMachine;
35 
36 #define CALL_ONCE_INITIALIZATION(function) \
37   static volatile sys::cas_flag initialized = 0; \
38   sys::cas_flag old_val = sys::CompareAndSwap(&initialized, 1, 0); \
39   if (old_val == 0) { \
40     function(Registry); \
41     sys::MemoryFence(); \
42     TsanIgnoreWritesBegin(); \
43     TsanHappensBefore(&initialized); \
44     initialized = 2; \
45     TsanIgnoreWritesEnd(); \
46   } else { \
47     sys::cas_flag tmp = initialized; \
48     sys::MemoryFence(); \
49     while (tmp != 2) { \
50       tmp = initialized; \
51       sys::MemoryFence(); \
52     } \
53   } \
54   TsanHappensAfter(&initialized);
55 
56 #define INITIALIZE_PASS(passName, arg, name, cfg, analysis) \
57   static void* initialize##passName##PassOnce(PassRegistry &Registry) { \
58     PassInfo *PI = new PassInfo(name, arg, & passName ::ID, \
59       PassInfo::NormalCtor_t(callDefaultCtor< passName >), cfg, analysis); \
60     Registry.registerPass(*PI, true); \
61     return PI; \
62   } \
63   void llvm::initialize##passName##Pass(PassRegistry &Registry) { \
64     CALL_ONCE_INITIALIZATION(initialize##passName##PassOnce) \
65   }
66 
67 #define INITIALIZE_PASS_BEGIN(passName, arg, name, cfg, analysis) \
68   static void* initialize##passName##PassOnce(PassRegistry &Registry) {
69 
70 #define INITIALIZE_PASS_DEPENDENCY(depName) \
71     initialize##depName##Pass(Registry);
72 #define INITIALIZE_AG_DEPENDENCY(depName) \
73     initialize##depName##AnalysisGroup(Registry);
74 
75 #define INITIALIZE_PASS_END(passName, arg, name, cfg, analysis) \
76     PassInfo *PI = new PassInfo(name, arg, & passName ::ID, \
77       PassInfo::NormalCtor_t(callDefaultCtor< passName >), cfg, analysis); \
78     Registry.registerPass(*PI, true); \
79     return PI; \
80   } \
81   void llvm::initialize##passName##Pass(PassRegistry &Registry) { \
82     CALL_ONCE_INITIALIZATION(initialize##passName##PassOnce) \
83   }
84 
85 #define INITIALIZE_PASS_WITH_OPTIONS(PassName, Arg, Name, Cfg, Analysis) \
86   INITIALIZE_PASS_BEGIN(PassName, Arg, Name, Cfg, Analysis) \
87   PassName::registerOptions(); \
88   INITIALIZE_PASS_END(PassName, Arg, Name, Cfg, Analysis)
89 
90 #define INITIALIZE_PASS_WITH_OPTIONS_BEGIN(PassName, Arg, Name, Cfg, Analysis) \
91   INITIALIZE_PASS_BEGIN(PassName, Arg, Name, Cfg, Analysis) \
92   PassName::registerOptions(); \
93 
94 template<typename PassName>
callDefaultCtor()95 Pass *callDefaultCtor() { return new PassName(); }
96 
callTargetMachineCtor(TargetMachine * TM)97 template <typename PassName> Pass *callTargetMachineCtor(TargetMachine *TM) {
98   return new PassName(TM);
99 }
100 
101 //===---------------------------------------------------------------------------
102 /// RegisterPass<t> template - This template class is used to notify the system
103 /// that a Pass is available for use, and registers it into the internal
104 /// database maintained by the PassManager.  Unless this template is used, opt,
105 /// for example will not be able to see the pass and attempts to create the pass
106 /// will fail. This template is used in the follow manner (at global scope, in
107 /// your .cpp file):
108 ///
109 /// static RegisterPass<YourPassClassName> tmp("passopt", "My Pass Name");
110 ///
111 /// This statement will cause your pass to be created by calling the default
112 /// constructor exposed by the pass.  If you have a different constructor that
113 /// must be called, create a global constructor function (which takes the
114 /// arguments you need and returns a Pass*) and register your pass like this:
115 ///
116 /// static RegisterPass<PassClassName> tmp("passopt", "My Name");
117 ///
118 template<typename passName>
119 struct RegisterPass : public PassInfo {
120 
121   // Register Pass using default constructor...
122   RegisterPass(const char *PassArg, const char *Name, bool CFGOnly = false,
123                bool is_analysis = false)
124     : PassInfo(Name, PassArg, &passName::ID,
125                PassInfo::NormalCtor_t(callDefaultCtor<passName>),
126                CFGOnly, is_analysis) {
127     PassRegistry::getPassRegistry()->registerPass(*this);
128   }
129 };
130 
131 
132 /// RegisterAnalysisGroup - Register a Pass as a member of an analysis _group_.
133 /// Analysis groups are used to define an interface (which need not derive from
134 /// Pass) that is required by passes to do their job.  Analysis Groups differ
135 /// from normal analyses because any available implementation of the group will
136 /// be used if it is available.
137 ///
138 /// If no analysis implementing the interface is available, a default
139 /// implementation is created and added.  A pass registers itself as the default
140 /// implementation by specifying 'true' as the second template argument of this
141 /// class.
142 ///
143 /// In addition to registering itself as an analysis group member, a pass must
144 /// register itself normally as well.  Passes may be members of multiple groups
145 /// and may still be "required" specifically by name.
146 ///
147 /// The actual interface may also be registered as well (by not specifying the
148 /// second template argument).  The interface should be registered to associate
149 /// a nice name with the interface.
150 ///
151 class RegisterAGBase : public PassInfo {
152 public:
153   RegisterAGBase(const char *Name,
154                  const void *InterfaceID,
155                  const void *PassID = nullptr,
156                  bool isDefault = false);
157 };
158 
159 template<typename Interface, bool Default = false>
160 struct RegisterAnalysisGroup : public RegisterAGBase {
RegisterAnalysisGroupRegisterAnalysisGroup161   explicit RegisterAnalysisGroup(PassInfo &RPB)
162     : RegisterAGBase(RPB.getPassName(),
163                      &Interface::ID, RPB.getTypeInfo(),
164                      Default) {
165   }
166 
RegisterAnalysisGroupRegisterAnalysisGroup167   explicit RegisterAnalysisGroup(const char *Name)
168     : RegisterAGBase(Name, &Interface::ID) {
169   }
170 };
171 
172 #define INITIALIZE_ANALYSIS_GROUP(agName, name, defaultPass) \
173   static void* initialize##agName##AnalysisGroupOnce(PassRegistry &Registry) { \
174     initialize##defaultPass##Pass(Registry); \
175     PassInfo *AI = new PassInfo(name, & agName :: ID); \
176     Registry.registerAnalysisGroup(& agName ::ID, 0, *AI, false, true); \
177     return AI; \
178   } \
179   void llvm::initialize##agName##AnalysisGroup(PassRegistry &Registry) { \
180     CALL_ONCE_INITIALIZATION(initialize##agName##AnalysisGroupOnce) \
181   }
182 
183 
184 #define INITIALIZE_AG_PASS(passName, agName, arg, name, cfg, analysis, def) \
185   static void* initialize##passName##PassOnce(PassRegistry &Registry) { \
186     if (!def) initialize##agName##AnalysisGroup(Registry); \
187     PassInfo *PI = new PassInfo(name, arg, & passName ::ID, \
188       PassInfo::NormalCtor_t(callDefaultCtor< passName >), cfg, analysis); \
189     Registry.registerPass(*PI, true); \
190     \
191     PassInfo *AI = new PassInfo(name, & agName :: ID); \
192     Registry.registerAnalysisGroup(& agName ::ID, & passName ::ID, \
193                                    *AI, def, true); \
194     return AI; \
195   } \
196   void llvm::initialize##passName##Pass(PassRegistry &Registry) { \
197     CALL_ONCE_INITIALIZATION(initialize##passName##PassOnce) \
198   }
199 
200 
201 #define INITIALIZE_AG_PASS_BEGIN(passName, agName, arg, n, cfg, analysis, def) \
202   static void* initialize##passName##PassOnce(PassRegistry &Registry) { \
203     if (!def) initialize##agName##AnalysisGroup(Registry);
204 
205 #define INITIALIZE_AG_PASS_END(passName, agName, arg, n, cfg, analysis, def) \
206     PassInfo *PI = new PassInfo(n, arg, & passName ::ID, \
207       PassInfo::NormalCtor_t(callDefaultCtor< passName >), cfg, analysis); \
208     Registry.registerPass(*PI, true); \
209     \
210     PassInfo *AI = new PassInfo(n, & agName :: ID); \
211     Registry.registerAnalysisGroup(& agName ::ID, & passName ::ID, \
212                                    *AI, def, true); \
213     return AI; \
214   } \
215   void llvm::initialize##passName##Pass(PassRegistry &Registry) { \
216     CALL_ONCE_INITIALIZATION(initialize##passName##PassOnce) \
217   }
218 
219 //===---------------------------------------------------------------------------
220 /// PassRegistrationListener class - This class is meant to be derived from by
221 /// clients that are interested in which passes get registered and unregistered
222 /// at runtime (which can be because of the RegisterPass constructors being run
223 /// as the program starts up, or may be because a shared object just got
224 /// loaded).
225 ///
226 struct PassRegistrationListener {
227 
PassRegistrationListenerPassRegistrationListener228   PassRegistrationListener() {}
~PassRegistrationListenerPassRegistrationListener229   virtual ~PassRegistrationListener() {}
230 
231   /// Callback functions - These functions are invoked whenever a pass is loaded
232   /// or removed from the current executable.
233   ///
passRegisteredPassRegistrationListener234   virtual void passRegistered(const PassInfo *) {}
235 
236   /// enumeratePasses - Iterate over the registered passes, calling the
237   /// passEnumerate callback on each PassInfo object.
238   ///
239   void enumeratePasses();
240 
241   /// passEnumerate - Callback function invoked when someone calls
242   /// enumeratePasses on this PassRegistrationListener object.
243   ///
passEnumeratePassRegistrationListener244   virtual void passEnumerate(const PassInfo *) {}
245 };
246 
247 
248 } // End llvm namespace
249 
250 #endif
251