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Diffstat (limited to 'lib/VMCore/Pass.cpp')
-rw-r--r-- | lib/VMCore/Pass.cpp | 323 |
1 files changed, 323 insertions, 0 deletions
diff --git a/lib/VMCore/Pass.cpp b/lib/VMCore/Pass.cpp new file mode 100644 index 0000000..6db5d7e --- /dev/null +++ b/lib/VMCore/Pass.cpp @@ -0,0 +1,323 @@ +//===- Pass.cpp - LLVM Pass Infrastructure Implementation -----------------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file implements the LLVM Pass infrastructure. It is primarily +// responsible with ensuring that passes are executed and batched together +// optimally. +// +//===----------------------------------------------------------------------===// + +#include "llvm/Pass.h" +#include "llvm/PassManager.h" +#include "llvm/Module.h" +#include "llvm/ModuleProvider.h" +#include "llvm/ADT/STLExtras.h" +#include "llvm/Support/ManagedStatic.h" +#include <algorithm> +#include <map> +#include <set> +using namespace llvm; + +//===----------------------------------------------------------------------===// +// Pass Implementation +// + +// Force out-of-line virtual method. +Pass::~Pass() { + delete Resolver; +} + +// Force out-of-line virtual method. +ModulePass::~ModulePass() { } + +bool Pass::mustPreserveAnalysisID(const PassInfo *AnalysisID) const { + return Resolver->getAnalysisIfAvailable(AnalysisID, true) != 0; +} + +// dumpPassStructure - Implement the -debug-passes=Structure option +void Pass::dumpPassStructure(unsigned Offset) { + cerr << std::string(Offset*2, ' ') << getPassName() << "\n"; +} + +/// getPassName - Return a nice clean name for a pass. This usually +/// implemented in terms of the name that is registered by one of the +/// Registration templates, but can be overloaded directly. +/// +const char *Pass::getPassName() const { + if (const PassInfo *PI = getPassInfo()) + return PI->getPassName(); + return "Unnamed pass: implement Pass::getPassName()"; +} + +// print - Print out the internal state of the pass. This is called by Analyze +// to print out the contents of an analysis. Otherwise it is not necessary to +// implement this method. +// +void Pass::print(std::ostream &O,const Module*) const { + O << "Pass::print not implemented for pass: '" << getPassName() << "'!\n"; +} + +// dump - call print(cerr); +void Pass::dump() const { + print(*cerr.stream(), 0); +} + +//===----------------------------------------------------------------------===// +// ImmutablePass Implementation +// +// Force out-of-line virtual method. +ImmutablePass::~ImmutablePass() { } + +//===----------------------------------------------------------------------===// +// FunctionPass Implementation +// + +// run - On a module, we run this pass by initializing, runOnFunction'ing once +// for every function in the module, then by finalizing. +// +bool FunctionPass::runOnModule(Module &M) { + bool Changed = doInitialization(M); + + for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I) + if (!I->isDeclaration()) // Passes are not run on external functions! + Changed |= runOnFunction(*I); + + return Changed | doFinalization(M); +} + +// run - On a function, we simply initialize, run the function, then finalize. +// +bool FunctionPass::run(Function &F) { + // Passes are not run on external functions! + if (F.isDeclaration()) return false; + + bool Changed = doInitialization(*F.getParent()); + Changed |= runOnFunction(F); + return Changed | doFinalization(*F.getParent()); +} + +//===----------------------------------------------------------------------===// +// BasicBlockPass Implementation +// + +// To run this pass on a function, we simply call runOnBasicBlock once for each +// function. +// +bool BasicBlockPass::runOnFunction(Function &F) { + bool Changed = doInitialization(F); + for (Function::iterator I = F.begin(), E = F.end(); I != E; ++I) + Changed |= runOnBasicBlock(*I); + return Changed | doFinalization(F); +} + +//===----------------------------------------------------------------------===// +// Pass Registration mechanism +// +namespace { +class PassRegistrar { + /// PassInfoMap - Keep track of the passinfo object for each registered llvm + /// pass. + typedef std::map<intptr_t, const PassInfo*> MapType; + MapType PassInfoMap; + + /// AnalysisGroupInfo - Keep track of information for each analysis group. + struct AnalysisGroupInfo { + const PassInfo *DefaultImpl; + std::set<const PassInfo *> Implementations; + AnalysisGroupInfo() : DefaultImpl(0) {} + }; + + /// AnalysisGroupInfoMap - Information for each analysis group. + std::map<const PassInfo *, AnalysisGroupInfo> AnalysisGroupInfoMap; + +public: + + const PassInfo *GetPassInfo(intptr_t TI) const { + MapType::const_iterator I = PassInfoMap.find(TI); + return I != PassInfoMap.end() ? I->second : 0; + } + + void RegisterPass(const PassInfo &PI) { + bool Inserted = + PassInfoMap.insert(std::make_pair(PI.getTypeInfo(),&PI)).second; + assert(Inserted && "Pass registered multiple times!"); Inserted=Inserted; + } + + void UnregisterPass(const PassInfo &PI) { + MapType::iterator I = PassInfoMap.find(PI.getTypeInfo()); + assert(I != PassInfoMap.end() && "Pass registered but not in map!"); + + // Remove pass from the map. + PassInfoMap.erase(I); + } + + void EnumerateWith(PassRegistrationListener *L) { + for (MapType::const_iterator I = PassInfoMap.begin(), + E = PassInfoMap.end(); I != E; ++I) + L->passEnumerate(I->second); + } + + + /// Analysis Group Mechanisms. + void RegisterAnalysisGroup(PassInfo *InterfaceInfo, + const PassInfo *ImplementationInfo, + bool isDefault) { + AnalysisGroupInfo &AGI = AnalysisGroupInfoMap[InterfaceInfo]; + assert(AGI.Implementations.count(ImplementationInfo) == 0 && + "Cannot add a pass to the same analysis group more than once!"); + AGI.Implementations.insert(ImplementationInfo); + if (isDefault) { + assert(AGI.DefaultImpl == 0 && InterfaceInfo->getNormalCtor() == 0 && + "Default implementation for analysis group already specified!"); + assert(ImplementationInfo->getNormalCtor() && + "Cannot specify pass as default if it does not have a default ctor"); + AGI.DefaultImpl = ImplementationInfo; + InterfaceInfo->setNormalCtor(ImplementationInfo->getNormalCtor()); + } + } +}; +} + +static std::vector<PassRegistrationListener*> *Listeners = 0; + +// FIXME: This should use ManagedStatic to manage the pass registrar. +// Unfortunately, we can't do this, because passes are registered with static +// ctors, and having llvm_shutdown clear this map prevents successful +// ressurection after llvm_shutdown is run. +static PassRegistrar *getPassRegistrar() { + static PassRegistrar *PassRegistrarObj = 0; + if (!PassRegistrarObj) + PassRegistrarObj = new PassRegistrar(); + return PassRegistrarObj; +} + +// getPassInfo - Return the PassInfo data structure that corresponds to this +// pass... +const PassInfo *Pass::getPassInfo() const { + return lookupPassInfo(PassID); +} + +const PassInfo *Pass::lookupPassInfo(intptr_t TI) { + return getPassRegistrar()->GetPassInfo(TI); +} + +void PassInfo::registerPass() { + getPassRegistrar()->RegisterPass(*this); + + // Notify any listeners. + if (Listeners) + for (std::vector<PassRegistrationListener*>::iterator + I = Listeners->begin(), E = Listeners->end(); I != E; ++I) + (*I)->passRegistered(this); +} + +void PassInfo::unregisterPass() { + getPassRegistrar()->UnregisterPass(*this); +} + +//===----------------------------------------------------------------------===// +// Analysis Group Implementation Code +//===----------------------------------------------------------------------===// + +// RegisterAGBase implementation +// +RegisterAGBase::RegisterAGBase(const char *Name, intptr_t InterfaceID, + intptr_t PassID, bool isDefault) + : PassInfo(Name, InterfaceID), + ImplementationInfo(0), isDefaultImplementation(isDefault) { + + InterfaceInfo = const_cast<PassInfo*>(Pass::lookupPassInfo(InterfaceID)); + if (InterfaceInfo == 0) { + // First reference to Interface, register it now. + registerPass(); + InterfaceInfo = this; + } + assert(isAnalysisGroup() && + "Trying to join an analysis group that is a normal pass!"); + + if (PassID) { + ImplementationInfo = Pass::lookupPassInfo(PassID); + assert(ImplementationInfo && + "Must register pass before adding to AnalysisGroup!"); + + // Make sure we keep track of the fact that the implementation implements + // the interface. + PassInfo *IIPI = const_cast<PassInfo*>(ImplementationInfo); + IIPI->addInterfaceImplemented(InterfaceInfo); + + getPassRegistrar()->RegisterAnalysisGroup(InterfaceInfo, IIPI, isDefault); + } +} + + +//===----------------------------------------------------------------------===// +// PassRegistrationListener implementation +// + +// PassRegistrationListener ctor - Add the current object to the list of +// PassRegistrationListeners... +PassRegistrationListener::PassRegistrationListener() { + if (!Listeners) Listeners = new std::vector<PassRegistrationListener*>(); + Listeners->push_back(this); +} + +// dtor - Remove object from list of listeners... +PassRegistrationListener::~PassRegistrationListener() { + std::vector<PassRegistrationListener*>::iterator I = + std::find(Listeners->begin(), Listeners->end(), this); + assert(Listeners && I != Listeners->end() && + "PassRegistrationListener not registered!"); + Listeners->erase(I); + + if (Listeners->empty()) { + delete Listeners; + Listeners = 0; + } +} + +// enumeratePasses - Iterate over the registered passes, calling the +// passEnumerate callback on each PassInfo object. +// +void PassRegistrationListener::enumeratePasses() { + getPassRegistrar()->EnumerateWith(this); +} + +//===----------------------------------------------------------------------===// +// AnalysisUsage Class Implementation +// + +namespace { + struct GetCFGOnlyPasses : public PassRegistrationListener { + typedef AnalysisUsage::VectorType VectorType; + VectorType &CFGOnlyList; + GetCFGOnlyPasses(VectorType &L) : CFGOnlyList(L) {} + + void passEnumerate(const PassInfo *P) { + if (P->isCFGOnlyPass()) + CFGOnlyList.push_back(P); + } + }; +} + +// setPreservesCFG - This function should be called to by the pass, iff they do +// not: +// +// 1. Add or remove basic blocks from the function +// 2. Modify terminator instructions in any way. +// +// This function annotates the AnalysisUsage info object to say that analyses +// that only depend on the CFG are preserved by this pass. +// +void AnalysisUsage::setPreservesCFG() { + // Since this transformation doesn't modify the CFG, it preserves all analyses + // that only depend on the CFG (like dominators, loop info, etc...) + GetCFGOnlyPasses(Preserved).enumeratePasses(); +} + + |