1 files changed, 148 insertions, 0 deletions
diff --git a/llvm/lib/CodeGen/MachineRegionInfo.cpp b/llvm/lib/CodeGen/MachineRegionInfo.cpp
new file mode 100644
index 0000000000000..2961d456be0d3
--- /dev/null
+++ b/llvm/lib/CodeGen/MachineRegionInfo.cpp
@@ -0,0 +1,148 @@
+//===- lib/Codegen/MachineRegionInfo.cpp ----------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/CodeGen/MachineRegionInfo.h"
+#include "llvm/ADT/Statistic.h"
+#include "llvm/Analysis/RegionInfoImpl.h"
+#include "llvm/CodeGen/MachinePostDominators.h"
+#include "llvm/Config/llvm-config.h"
+#include "llvm/Pass.h"
+#include "llvm/Support/Compiler.h"
+#include "llvm/Support/Debug.h"
+
+#define DEBUG_TYPE "machine-region-info"
+
+using namespace llvm;
+
+STATISTIC(numMachineRegions,       "The # of machine regions");
+STATISTIC(numMachineSimpleRegions, "The # of simple machine regions");
+
+namespace llvm {
+
+template class RegionBase<RegionTraits<MachineFunction>>;
+template class RegionNodeBase<RegionTraits<MachineFunction>>;
+template class RegionInfoBase<RegionTraits<MachineFunction>>;
+
+} // end namespace llvm
+
+//===----------------------------------------------------------------------===//
+// MachineRegion implementation
+
+MachineRegion::MachineRegion(MachineBasicBlock *Entry, MachineBasicBlock *Exit,
+                             MachineRegionInfo* RI,
+                             MachineDominatorTree *DT, MachineRegion *Parent) :
+  RegionBase<RegionTraits<MachineFunction>>(Entry, Exit, RI, DT, Parent) {}
+
+MachineRegion::~MachineRegion() = default;
+
+//===----------------------------------------------------------------------===//
+// MachineRegionInfo implementation
+
+MachineRegionInfo::MachineRegionInfo() = default;
+
+MachineRegionInfo::~MachineRegionInfo() = default;
+
+void MachineRegionInfo::updateStatistics(MachineRegion *R) {
+  ++numMachineRegions;
+
+  // TODO: Slow. Should only be enabled if -stats is used.
+  if (R->isSimple())
+    ++numMachineSimpleRegions;
+}
+
+void MachineRegionInfo::recalculate(MachineFunction &F,
+                                    MachineDominatorTree *DT_,
+                                    MachinePostDominatorTree *PDT_,
+                                    MachineDominanceFrontier *DF_) {
+  DT = DT_;
+  PDT = PDT_;
+  DF = DF_;
+
+  MachineBasicBlock *Entry = GraphTraits<MachineFunction*>::getEntryNode(&F);
+
+  TopLevelRegion = new MachineRegion(Entry, nullptr, this, DT, nullptr);
+  updateStatistics(TopLevelRegion);
+  calculate(F);
+}
+
+//===----------------------------------------------------------------------===//
+// MachineRegionInfoPass implementation
+//
+
+MachineRegionInfoPass::MachineRegionInfoPass() : MachineFunctionPass(ID) {
+  initializeMachineRegionInfoPassPass(*PassRegistry::getPassRegistry());
+}
+
+MachineRegionInfoPass::~MachineRegionInfoPass() = default;
+
+bool MachineRegionInfoPass::runOnMachineFunction(MachineFunction &F) {
+  releaseMemory();
+
+  auto DT = &getAnalysis<MachineDominatorTree>();
+  auto PDT = &getAnalysis<MachinePostDominatorTree>();
+  auto DF = &getAnalysis<MachineDominanceFrontier>();
+
+  RI.recalculate(F, DT, PDT, DF);
+
+  LLVM_DEBUG(RI.dump());
+
+  return false;
+}
+
+void MachineRegionInfoPass::releaseMemory() {
+  RI.releaseMemory();
+}
+
+void MachineRegionInfoPass::verifyAnalysis() const {
+  // Only do verification when user wants to, otherwise this expensive check
+  // will be invoked by PMDataManager::verifyPreservedAnalysis when
+  // a regionpass (marked PreservedAll) finish.
+  if (MachineRegionInfo::VerifyRegionInfo)
+    RI.verifyAnalysis();
+}
+
+void MachineRegionInfoPass::getAnalysisUsage(AnalysisUsage &AU) const {
+  AU.setPreservesAll();
+  AU.addRequired<MachineDominatorTree>();
+  AU.addRequired<MachinePostDominatorTree>();
+  AU.addRequired<MachineDominanceFrontier>();
+  MachineFunctionPass::getAnalysisUsage(AU);
+}
+
+void MachineRegionInfoPass::print(raw_ostream &OS, const Module *) const {
+  RI.print(OS);
+}
+
+#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
+LLVM_DUMP_METHOD void MachineRegionInfoPass::dump() const {
+  RI.dump();
+}
+#endif
+
+char MachineRegionInfoPass::ID = 0;
+char &MachineRegionInfoPassID = MachineRegionInfoPass::ID;
+
+INITIALIZE_PASS_BEGIN(MachineRegionInfoPass, DEBUG_TYPE,
+                      "Detect single entry single exit regions", true, true)
+INITIALIZE_PASS_DEPENDENCY(MachineDominatorTree)
+INITIALIZE_PASS_DEPENDENCY(MachinePostDominatorTree)
+INITIALIZE_PASS_DEPENDENCY(MachineDominanceFrontier)
+INITIALIZE_PASS_END(MachineRegionInfoPass, DEBUG_TYPE,
+                    "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 *createMachineRegionInfoPass() {
+  return new MachineRegionInfoPass();
+}
+
+} // end namespace llvm