Imported Upstream version 5.18.0.247

Former-commit-id: 2d6af2e4ed0eda5cbdc2946446ef7718456ad190

external/llvm/lib/CodeGen/MachineDominators.cpp

@@ -1,158 +0,0 @@
-//===- MachineDominators.cpp - Machine Dominator Calculation --------------===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// This file implements simple dominator construction algorithms for finding
-// forward dominators on machine functions.
-//
-//===----------------------------------------------------------------------===//
-
-#include "llvm/CodeGen/MachineDominators.h"
-#include "llvm/ADT/SmallBitVector.h"
-#include "llvm/CodeGen/Passes.h"
-#include "llvm/Support/CommandLine.h"
-
-using namespace llvm;
-
-// Always verify dominfo if expensive checking is enabled.
-#ifdef EXPENSIVE_CHECKS
-static bool VerifyMachineDomInfo = true;
-#else
-static bool VerifyMachineDomInfo = false;
-#endif
-static cl::opt<bool, true> VerifyMachineDomInfoX(
-    "verify-machine-dom-info", cl::location(VerifyMachineDomInfo), cl::Hidden,
-    cl::desc("Verify machine dominator info (time consuming)"));
-
-namespace llvm {
-template class DomTreeNodeBase<MachineBasicBlock>;
-template class DominatorTreeBase<MachineBasicBlock, false>; // DomTreeBase
-}
-
-char MachineDominatorTree::ID = 0;
-
-INITIALIZE_PASS(MachineDominatorTree, "machinedomtree",
-                "MachineDominator Tree Construction", true, true)
-
-char &llvm::MachineDominatorsID = MachineDominatorTree::ID;
-
-void MachineDominatorTree::getAnalysisUsage(AnalysisUsage &AU) const {
-  AU.setPreservesAll();
-  MachineFunctionPass::getAnalysisUsage(AU);
-}
-
-bool MachineDominatorTree::runOnMachineFunction(MachineFunction &F) {
-  CriticalEdgesToSplit.clear();
-  NewBBs.clear();
-  DT.reset(new DomTreeBase<MachineBasicBlock>());
-  DT->recalculate(F);
-  return false;
-}
-
-MachineDominatorTree::MachineDominatorTree()
-    : MachineFunctionPass(ID) {
-  initializeMachineDominatorTreePass(*PassRegistry::getPassRegistry());
-}
-
-void MachineDominatorTree::releaseMemory() {
-  CriticalEdgesToSplit.clear();
-  DT.reset(nullptr);
-}
-
-void MachineDominatorTree::verifyAnalysis() const {
-  if (DT && VerifyMachineDomInfo)
-    verifyDomTree();
-}
-
-void MachineDominatorTree::print(raw_ostream &OS, const Module*) const {
-  if (DT)
-    DT->print(OS);
-}
-
-void MachineDominatorTree::applySplitCriticalEdges() const {
-  // Bail out early if there is nothing to do.
-  if (CriticalEdgesToSplit.empty())
-    return;
-
-  // For each element in CriticalEdgesToSplit, remember whether or not element
-  // is the new immediate domminator of its successor. The mapping is done by
-  // index, i.e., the information for the ith element of CriticalEdgesToSplit is
-  // the ith element of IsNewIDom.
-  SmallBitVector IsNewIDom(CriticalEdgesToSplit.size(), true);
-  size_t Idx = 0;
-
-  // Collect all the dominance properties info, before invalidating
-  // the underlying DT.
-  for (CriticalEdge &Edge : CriticalEdgesToSplit) {
-    // Update dominator information.
-    MachineBasicBlock *Succ = Edge.ToBB;
-    MachineDomTreeNode *SuccDTNode = DT->getNode(Succ);
-
-    for (MachineBasicBlock *PredBB : Succ->predecessors()) {
-      if (PredBB == Edge.NewBB)
-        continue;
-      // If we are in this situation:
-      // FromBB1        FromBB2
-      //    +              +
-      //   + +            + +
-      //  +   +          +   +
-      // ...  Split1  Split2 ...
-      //           +   +
-      //            + +
-      //             +
-      //            Succ
-      // Instead of checking the domiance property with Split2, we check it with
-      // FromBB2 since Split2 is still unknown of the underlying DT structure.
-      if (NewBBs.count(PredBB)) {
-        assert(PredBB->pred_size() == 1 && "A basic block resulting from a "
-                                           "critical edge split has more "
-                                           "than one predecessor!");
-        PredBB = *PredBB->pred_begin();
-      }
-      if (!DT->dominates(SuccDTNode, DT->getNode(PredBB))) {
-        IsNewIDom[Idx] = false;
-        break;
-      }
-    }
-    ++Idx;
-  }
-
-  // Now, update DT with the collected dominance properties info.
-  Idx = 0;
-  for (CriticalEdge &Edge : CriticalEdgesToSplit) {
-    // We know FromBB dominates NewBB.
-    MachineDomTreeNode *NewDTNode = DT->addNewBlock(Edge.NewBB, Edge.FromBB);
-
-    // If all the other predecessors of "Succ" are dominated by "Succ" itself
-    // then the new block is the new immediate dominator of "Succ". Otherwise,
-    // the new block doesn't dominate anything.
-    if (IsNewIDom[Idx])
-      DT->changeImmediateDominator(DT->getNode(Edge.ToBB), NewDTNode);
-    ++Idx;
-  }
-  NewBBs.clear();
-  CriticalEdgesToSplit.clear();
-}
-
-void MachineDominatorTree::verifyDomTree() const {
-  if (!DT)
-    return;
-  MachineFunction &F = *getRoot()->getParent();
-
-  DomTreeBase<MachineBasicBlock> OtherDT;
-  OtherDT.recalculate(F);
-  if (getRootNode()->getBlock() != OtherDT.getRootNode()->getBlock() ||
-      DT->compare(OtherDT)) {
-    errs() << "MachineDominatorTree for function " << F.getName()
-           << " is not up to date!\nComputed:\n";
-    DT->print(errs());
-    errs() << "\nActual:\n";
-    OtherDT.print(errs());
-    abort();
-  }
-}