lib/CodeGen/MachineRegionInfo.cpp

   1
   2 #include "llvm/CodeGen/MachineRegionInfo.h"
   3 #include "llvm/CodeGen/MachinePostDominators.h"
   4 #include "llvm/ADT/Statistic.h"
   5 #include "llvm/Analysis/RegionInfoImpl.h"
   6
   7 using namespace llvm;
   8
   9 STATISTIC(numMachineRegions,       "The # of machine regions");
  10 STATISTIC(numMachineSimpleRegions, "The # of simple machine regions");
  11
  12 namespace llvm {
  13 template class RegionBase<RegionTraits<MachineFunction>>;
  14 template class RegionNodeBase<RegionTraits<MachineFunction>>;
  15 template class RegionInfoBase<RegionTraits<MachineFunction>>;
  16 }
  17
  18 //===----------------------------------------------------------------------===//
  19 // MachineRegion implementation
  20 //
  21
  22 MachineRegion::MachineRegion(MachineBasicBlock *Entry, MachineBasicBlock *Exit,
  23                              MachineRegionInfo* RI,
  24                              MachineDominatorTree *DT, MachineRegion *Parent) :
  25   RegionBase<RegionTraits<MachineFunction>>(Entry, Exit, RI, DT, Parent) {
  26
  27 }
  28
  29 MachineRegion::~MachineRegion() { }
  30
  31 //===----------------------------------------------------------------------===//
  32 // MachineRegionInfo implementation
  33 //
  34
  35 MachineRegionInfo::MachineRegionInfo() :
  36   RegionInfoBase<RegionTraits<MachineFunction>>() {
  37
  38 }
  39
  40 MachineRegionInfo::~MachineRegionInfo() {
  41
  42 }
  43
  44 void MachineRegionInfo::updateStatistics(MachineRegion *R) {
  45   ++numMachineRegions;
  46
  47   // TODO: Slow. Should only be enabled if -stats is used.
  48   if (R->isSimple())
  49     ++numMachineSimpleRegions;
  50 }
  51
  52 void MachineRegionInfo::recalculate(MachineFunction &F,
  53                                     MachineDominatorTree *DT_,
  54                                     MachinePostDominatorTree *PDT_,
  55                                     MachineDominanceFrontier *DF_) {
  56   DT = DT_;
  57   PDT = PDT_;
  58   DF = DF_;
  59
  60   MachineBasicBlock *Entry = GraphTraits<MachineFunction*>::getEntryNode(&F);
  61
  62   TopLevelRegion = new MachineRegion(Entry, nullptr, this, DT, nullptr);
  63   updateStatistics(TopLevelRegion);
  64   calculate(F);
  65 }
  66
  67 //===----------------------------------------------------------------------===//
  68 // MachineRegionInfoPass implementation
  69 //
  70
  71 MachineRegionInfoPass::MachineRegionInfoPass() : MachineFunctionPass(ID) {
  72   initializeMachineRegionInfoPassPass(*PassRegistry::getPassRegistry());
  73 }
  74
  75 MachineRegionInfoPass::~MachineRegionInfoPass() {
  76
  77 }
  78
  79 bool MachineRegionInfoPass::runOnMachineFunction(MachineFunction &F) {
  80   releaseMemory();
  81
  82   auto DT = &getAnalysis<MachineDominatorTree>();
  83   auto PDT = &getAnalysis<MachinePostDominatorTree>();
  84   auto DF = &getAnalysis<MachineDominanceFrontier>();
  85
  86   RI.recalculate(F, DT, PDT, DF);
  87   return false;
  88 }
  89
  90 void MachineRegionInfoPass::releaseMemory() {
  91   RI.releaseMemory();
  92 }
  93
  94 void MachineRegionInfoPass::verifyAnalysis() const {
  95   // Only do verification when user wants to, otherwise this expensive check
  96   // will be invoked by PMDataManager::verifyPreservedAnalysis when
  97   // a regionpass (marked PreservedAll) finish.
  98   if (MachineRegionInfo::VerifyRegionInfo)
  99     RI.verifyAnalysis();
 100 }
 101
 102 void MachineRegionInfoPass::getAnalysisUsage(AnalysisUsage &AU) const {
 103   AU.setPreservesAll();
 104   AU.addRequiredTransitive<DominatorTreeWrapperPass>();
 105   AU.addRequired<PostDominatorTree>();
 106   AU.addRequired<DominanceFrontier>();
 107 }
 108
 109 void MachineRegionInfoPass::print(raw_ostream &OS, const Module *) const {
 110   RI.print(OS);
 111 }
 112
 113 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
 114 void MachineRegionInfoPass::dump() const {
 115   RI.dump();
 116 }
 117 #endif
 118
 119 char MachineRegionInfoPass::ID = 0;
 120
 121 INITIALIZE_PASS_BEGIN(MachineRegionInfoPass, "regions",
 122                 "Detect single entry single exit regions", true, true)
 123 INITIALIZE_PASS_DEPENDENCY(MachineDominatorTree)
 124 INITIALIZE_PASS_DEPENDENCY(MachinePostDominatorTree)
 125 INITIALIZE_PASS_DEPENDENCY(MachineDominanceFrontier)
 126 INITIALIZE_PASS_END(MachineRegionInfoPass, "regions",
 127                 "Detect single entry single exit regions", true, true)
 128
 129 // Create methods available outside of this file, to use them
 130 // "include/llvm/LinkAllPasses.h". Otherwise the pass would be deleted by
 131 // the link time optimization.
 132
 133 namespace llvm {
 134   FunctionPass *createMachineRegionInfoPass() {
 135     return new MachineRegionInfoPass();
 136   }
 137 }
 138