1 //===- Pass.cpp - LLVM Pass Infrastructure Implementation -----------------===//
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 the LLVM Pass infrastructure. It is primarily
11 // responsible with ensuring that passes are executed and batched together
14 //===----------------------------------------------------------------------===//
16 #include "llvm/PassManager.h"
17 #include "llvm/Module.h"
18 #include "llvm/ModuleProvider.h"
19 #include "llvm/ADT/STLExtras.h"
20 #include "llvm/Support/ManagedStatic.h"
25 //===----------------------------------------------------------------------===//
26 // Pass Implementation
29 // Force out-of-line virtual method.
34 // Force out-of-line virtual method.
35 ModulePass::~ModulePass() { }
37 bool Pass::mustPreserveAnalysisID(const PassInfo *AnalysisID) const {
38 return Resolver->getAnalysisToUpdate(AnalysisID, true) != 0;
41 // dumpPassStructure - Implement the -debug-passes=Structure option
42 void Pass::dumpPassStructure(unsigned Offset) {
43 cerr << std::string(Offset*2, ' ') << getPassName() << "\n";
46 // getPassName - Use C++ RTTI to get a SOMEWHAT intelligible name for the pass.
48 const char *Pass::getPassName() const {
49 if (const PassInfo *PI = getPassInfo())
50 return PI->getPassName();
51 return "Unnamed pass: implement Pass::getPassName()";
54 // print - Print out the internal state of the pass. This is called by Analyze
55 // to print out the contents of an analysis. Otherwise it is not necessary to
56 // implement this method.
58 void Pass::print(std::ostream &O,const Module*) const {
59 O << "Pass::print not implemented for pass: '" << getPassName() << "'!\n";
62 // dump - call print(cerr);
63 void Pass::dump() const {
64 print(*cerr.stream(), 0);
67 //===----------------------------------------------------------------------===//
68 // ImmutablePass Implementation
70 // Force out-of-line virtual method.
71 ImmutablePass::~ImmutablePass() { }
73 //===----------------------------------------------------------------------===//
74 // FunctionPass Implementation
77 // run - On a module, we run this pass by initializing, runOnFunction'ing once
78 // for every function in the module, then by finalizing.
80 bool FunctionPass::runOnModule(Module &M) {
81 bool Changed = doInitialization(M);
83 for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I)
84 if (!I->isDeclaration()) // Passes are not run on external functions!
85 Changed |= runOnFunction(*I);
87 return Changed | doFinalization(M);
90 // run - On a function, we simply initialize, run the function, then finalize.
92 bool FunctionPass::run(Function &F) {
93 // Passes are not run on external functions!
94 if (F.isDeclaration()) return false;
96 bool Changed = doInitialization(*F.getParent());
97 Changed |= runOnFunction(F);
98 return Changed | doFinalization(*F.getParent());
101 //===----------------------------------------------------------------------===//
102 // BasicBlockPass Implementation
105 // To run this pass on a function, we simply call runOnBasicBlock once for each
108 bool BasicBlockPass::runOnFunction(Function &F) {
109 bool Changed = doInitialization(F);
110 for (Function::iterator I = F.begin(), E = F.end(); I != E; ++I)
111 Changed |= runOnBasicBlock(*I);
112 return Changed | doFinalization(F);
115 //===----------------------------------------------------------------------===//
116 // Pass Registration mechanism
119 class PassRegistrar {
120 /// PassInfoMap - Keep track of the passinfo object for each registered llvm
122 std::map<intptr_t, PassInfo*> PassInfoMap;
124 /// AnalysisGroupInfo - Keep track of information for each analysis group.
125 struct AnalysisGroupInfo {
126 const PassInfo *DefaultImpl;
127 std::set<const PassInfo *> Implementations;
128 AnalysisGroupInfo() : DefaultImpl(0) {}
131 /// AnalysisGroupInfoMap - Information for each analysis group.
132 std::map<const PassInfo *, AnalysisGroupInfo> AnalysisGroupInfoMap;
136 const PassInfo *GetPassInfo(intptr_t TI) const {
137 std::map<intptr_t, PassInfo*>::const_iterator I = PassInfoMap.find(TI);
138 return I != PassInfoMap.end() ? I->second : 0;
141 void RegisterPass(PassInfo &PI) {
143 PassInfoMap.insert(std::make_pair(PI.getTypeInfo(),&PI)).second;
144 assert(Inserted && "Pass registered multiple times!");
147 void UnregisterPass(PassInfo &PI) {
148 std::map<intptr_t, PassInfo*>::iterator I =
149 PassInfoMap.find(PI.getTypeInfo());
150 assert(I != PassInfoMap.end() && "Pass registered but not in map!");
152 // Remove pass from the map.
153 PassInfoMap.erase(I);
156 void EnumerateWith(PassRegistrationListener *L) {
157 for (std::map<intptr_t, PassInfo*>::const_iterator I = PassInfoMap.begin(),
158 E = PassInfoMap.end(); I != E; ++I)
159 L->passEnumerate(I->second);
163 /// Analysis Group Mechanisms.
164 void RegisterAnalysisGroup(PassInfo *InterfaceInfo,
165 const PassInfo *ImplementationInfo,
167 AnalysisGroupInfo &AGI = AnalysisGroupInfoMap[InterfaceInfo];
168 assert(AGI.Implementations.count(ImplementationInfo) == 0 &&
169 "Cannot add a pass to the same analysis group more than once!");
170 AGI.Implementations.insert(ImplementationInfo);
172 assert(AGI.DefaultImpl == 0 && InterfaceInfo->getNormalCtor() == 0 &&
173 "Default implementation for analysis group already specified!");
174 assert(ImplementationInfo->getNormalCtor() &&
175 "Cannot specify pass as default if it does not have a default ctor");
176 AGI.DefaultImpl = ImplementationInfo;
177 InterfaceInfo->setNormalCtor(ImplementationInfo->getNormalCtor());
183 static std::vector<PassRegistrationListener*> *Listeners = 0;
185 // FIXME: This should use ManagedStatic to manage the pass registrar.
186 // Unfortunately, we can't do this, because passes are registered with static
187 // ctors, and having llvm_shutdown clear this map prevents successful
188 // ressurection after llvm_shutdown is run.
189 static PassRegistrar *getPassRegistrar() {
190 static PassRegistrar *PassRegistrarObj = 0;
191 if (!PassRegistrarObj)
192 PassRegistrarObj = new PassRegistrar();
193 return PassRegistrarObj;
196 // getPassInfo - Return the PassInfo data structure that corresponds to this
198 const PassInfo *Pass::getPassInfo() const {
199 return lookupPassInfo(PassID);
202 const PassInfo *Pass::lookupPassInfo(intptr_t TI) {
203 return getPassRegistrar()->GetPassInfo(TI);
206 void RegisterPassBase::registerPass() {
207 getPassRegistrar()->RegisterPass(PIObj);
209 // Notify any listeners.
211 for (std::vector<PassRegistrationListener*>::iterator
212 I = Listeners->begin(), E = Listeners->end(); I != E; ++I)
213 (*I)->passRegistered(&PIObj);
216 void RegisterPassBase::unregisterPass() {
217 getPassRegistrar()->UnregisterPass(PIObj);
220 //===----------------------------------------------------------------------===//
221 // Analysis Group Implementation Code
222 //===----------------------------------------------------------------------===//
224 // RegisterAGBase implementation
226 RegisterAGBase::RegisterAGBase(intptr_t InterfaceID,
227 intptr_t PassID, bool isDefault)
228 : RegisterPassBase(InterfaceID),
229 ImplementationInfo(0), isDefaultImplementation(isDefault) {
231 InterfaceInfo = const_cast<PassInfo*>(Pass::lookupPassInfo(InterfaceID));
232 if (InterfaceInfo == 0) {
233 // First reference to Interface, register it now.
235 InterfaceInfo = &PIObj;
237 assert(PIObj.isAnalysisGroup() &&
238 "Trying to join an analysis group that is a normal pass!");
241 ImplementationInfo = Pass::lookupPassInfo(PassID);
242 assert(ImplementationInfo &&
243 "Must register pass before adding to AnalysisGroup!");
245 // Make sure we keep track of the fact that the implementation implements
247 PassInfo *IIPI = const_cast<PassInfo*>(ImplementationInfo);
248 IIPI->addInterfaceImplemented(InterfaceInfo);
250 getPassRegistrar()->RegisterAnalysisGroup(InterfaceInfo, IIPI, isDefault);
254 void RegisterAGBase::setGroupName(const char *Name) {
255 assert(InterfaceInfo->getPassName()[0] == 0 && "Interface Name already set!");
256 InterfaceInfo->setPassName(Name);
260 //===----------------------------------------------------------------------===//
261 // PassRegistrationListener implementation
264 // PassRegistrationListener ctor - Add the current object to the list of
265 // PassRegistrationListeners...
266 PassRegistrationListener::PassRegistrationListener() {
267 if (!Listeners) Listeners = new std::vector<PassRegistrationListener*>();
268 Listeners->push_back(this);
271 // dtor - Remove object from list of listeners...
272 PassRegistrationListener::~PassRegistrationListener() {
273 std::vector<PassRegistrationListener*>::iterator I =
274 std::find(Listeners->begin(), Listeners->end(), this);
275 assert(Listeners && I != Listeners->end() &&
276 "PassRegistrationListener not registered!");
279 if (Listeners->empty()) {
285 // enumeratePasses - Iterate over the registered passes, calling the
286 // passEnumerate callback on each PassInfo object.
288 void PassRegistrationListener::enumeratePasses() {
289 getPassRegistrar()->EnumerateWith(this);
292 //===----------------------------------------------------------------------===//
293 // AnalysisUsage Class Implementation
297 struct GetCFGOnlyPasses : public PassRegistrationListener {
298 std::vector<AnalysisID> &CFGOnlyList;
299 GetCFGOnlyPasses(std::vector<AnalysisID> &L) : CFGOnlyList(L) {}
301 void passEnumerate(const PassInfo *P) {
302 if (P->isCFGOnlyPass())
303 CFGOnlyList.push_back(P);
308 // setPreservesCFG - This function should be called to by the pass, iff they do
311 // 1. Add or remove basic blocks from the function
312 // 2. Modify terminator instructions in any way.
314 // This function annotates the AnalysisUsage info object to say that analyses
315 // that only depend on the CFG are preserved by this pass.
317 void AnalysisUsage::setPreservesCFG() {
318 // Since this transformation doesn't modify the CFG, it preserves all analyses
319 // that only depend on the CFG (like dominators, loop info, etc...)
320 GetCFGOnlyPasses(Preserved).enumeratePasses();