//===- RegionInfo.cpp - SESE region detection analysis --------------------===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // Detects single entry single exit regions in the control flow graph. //===----------------------------------------------------------------------===// #include "llvm/Analysis/RegionInfo.h" #include "llvm/ADT/PostOrderIterator.h" #include "llvm/ADT/Statistic.h" #include "llvm/Analysis/LoopInfo.h" #include "llvm/Analysis/RegionInfoImpl.h" #include "llvm/Analysis/RegionIterator.h" #include "llvm/Support/CommandLine.h" #include "llvm/Support/Debug.h" #include "llvm/Support/ErrorHandling.h" #include #include #include #ifndef NDEBUG #include "llvm/Analysis/RegionPrinter.h" #endif using namespace llvm; #define DEBUG_TYPE "region" namespace llvm { template class RegionBase>; template class RegionNodeBase>; template class RegionInfoBase>; } STATISTIC(numRegions, "The # of regions"); STATISTIC(numSimpleRegions, "The # of simple regions"); // Always verify if expensive checking is enabled. static cl::opt VerifyRegionInfoX( "verify-region-info", cl::location(RegionInfoBase>::VerifyRegionInfo), cl::desc("Verify region info (time consuming)")); static cl::opt printStyleX("print-region-style", cl::location(RegionInfo::printStyle), cl::Hidden, cl::desc("style of printing regions"), cl::values( clEnumValN(Region::PrintNone, "none", "print no details"), clEnumValN(Region::PrintBB, "bb", "print regions in detail with block_iterator"), clEnumValN(Region::PrintRN, "rn", "print regions in detail with element_iterator"), clEnumValEnd)); //===----------------------------------------------------------------------===// // Region implementation // Region::Region(BasicBlock *Entry, BasicBlock *Exit, RegionInfo* RI, DominatorTree *DT, Region *Parent) : RegionBase>(Entry, Exit, RI, DT, Parent) { } Region::~Region() { } //===----------------------------------------------------------------------===// // RegionInfo implementation // RegionInfo::RegionInfo() : RegionInfoBase>() { } RegionInfo::~RegionInfo() { } void RegionInfo::updateStatistics(Region *R) { ++numRegions; // TODO: Slow. Should only be enabled if -stats is used. if (R->isSimple()) ++numSimpleRegions; } void RegionInfo::recalculate(Function &F, DominatorTree *DT_, PostDominatorTree *PDT_, DominanceFrontier *DF_) { DT = DT_; PDT = PDT_; DF = DF_; TopLevelRegion = new Region(&F.getEntryBlock(), nullptr, this, DT, nullptr); updateStatistics(TopLevelRegion); calculate(F); } #ifndef NDEBUG void RegionInfo::view() { viewRegion(this); } void RegionInfo::viewOnly() { viewRegionOnly(this); } #endif //===----------------------------------------------------------------------===// // RegionInfoPass implementation // RegionInfoPass::RegionInfoPass() : FunctionPass(ID) { initializeRegionInfoPassPass(*PassRegistry::getPassRegistry()); } RegionInfoPass::~RegionInfoPass() { } bool RegionInfoPass::runOnFunction(Function &F) { releaseMemory(); auto DT = &getAnalysis().getDomTree(); auto PDT = &getAnalysis().getPostDomTree(); auto DF = &getAnalysis().getDominanceFrontier(); RI.recalculate(F, DT, PDT, DF); return false; } void RegionInfoPass::releaseMemory() { RI.releaseMemory(); } void RegionInfoPass::verifyAnalysis() const { RI.verifyAnalysis(); } void RegionInfoPass::getAnalysisUsage(AnalysisUsage &AU) const { AU.setPreservesAll(); AU.addRequiredTransitive(); AU.addRequired(); AU.addRequired(); } void RegionInfoPass::print(raw_ostream &OS, const Module *) const { RI.print(OS); } #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP) LLVM_DUMP_METHOD void RegionInfoPass::dump() const { RI.dump(); } #endif char RegionInfoPass::ID = 0; INITIALIZE_PASS_BEGIN(RegionInfoPass, "regions", "Detect single entry single exit regions", true, true) INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass) INITIALIZE_PASS_DEPENDENCY(PostDominatorTreeWrapperPass) INITIALIZE_PASS_DEPENDENCY(DominanceFrontierWrapperPass) INITIALIZE_PASS_END(RegionInfoPass, "regions", "Detect single entry single exit regions", true, true) // Create methods available outside of this file, to use them // "include/llvm/LinkAllPasses.h". Otherwise the pass would be deleted by // the link time optimization. namespace llvm { FunctionPass *createRegionInfoPass() { return new RegionInfoPass(); } }