Remove LLVM 8.0.1 files.

1 files changed, 0 insertions, 552 deletions

diff --git a/gnu/llvm/lib/Transforms/Utils/LowerSwitch.cpp b/gnu/llvm/lib/Transforms/Utils/LowerSwitch.cpp
deleted file mode 100644
index d019a44fc70..00000000000
--- a/gnu/llvm/lib/Transforms/Utils/LowerSwitch.cpp
+++ /dev/null
@@ -1,552 +0,0 @@
-//===- LowerSwitch.cpp - Eliminate Switch instructions --------------------===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// The LowerSwitch transformation rewrites switch instructions with a sequence
-// of branches, which allows targets to get away with not implementing the
-// switch instruction until it is convenient.
-//
-//===----------------------------------------------------------------------===//
-
-#include "llvm/ADT/DenseMap.h"
-#include "llvm/ADT/STLExtras.h"
-#include "llvm/ADT/SmallPtrSet.h"
-#include "llvm/ADT/SmallVector.h"
-#include "llvm/IR/BasicBlock.h"
-#include "llvm/IR/CFG.h"
-#include "llvm/IR/Constants.h"
-#include "llvm/IR/Function.h"
-#include "llvm/IR/InstrTypes.h"
-#include "llvm/IR/Instructions.h"
-#include "llvm/IR/Value.h"
-#include "llvm/Pass.h"
-#include "llvm/Support/Casting.h"
-#include "llvm/Support/Compiler.h"
-#include "llvm/Support/Debug.h"
-#include "llvm/Support/raw_ostream.h"
-#include "llvm/Transforms/Utils.h"
-#include "llvm/Transforms/Utils/BasicBlockUtils.h"
-#include <algorithm>
-#include <cassert>
-#include <cstdint>
-#include <iterator>
-#include <limits>
-#include <vector>
-
-using namespace llvm;
-
-#define DEBUG_TYPE "lower-switch"
-
-namespace {
-
-  struct IntRange {
-    int64_t Low, High;
-  };
-
-} // end anonymous namespace
-
-// Return true iff R is covered by Ranges.
-static bool IsInRanges(const IntRange &R,
-                       const std::vector<IntRange> &Ranges) {
-  // Note: Ranges must be sorted, non-overlapping and non-adjacent.
-
-  // Find the first range whose High field is >= R.High,
-  // then check if the Low field is <= R.Low. If so, we
-  // have a Range that covers R.
-  auto I = std::lower_bound(
-      Ranges.begin(), Ranges.end(), R,
-      [](const IntRange &A, const IntRange &B) { return A.High < B.High; });
-  return I != Ranges.end() && I->Low <= R.Low;
-}
-
-namespace {
-
-  /// Replace all SwitchInst instructions with chained branch instructions.
-  class LowerSwitch : public FunctionPass {
-  public:
-    // Pass identification, replacement for typeid
-    static char ID;
-
-    LowerSwitch() : FunctionPass(ID) {
-      initializeLowerSwitchPass(*PassRegistry::getPassRegistry());
-    }
-
-    bool runOnFunction(Function &F) override;
-
-    struct CaseRange {
-      ConstantInt* Low;
-      ConstantInt* High;
-      BasicBlock* BB;
-
-      CaseRange(ConstantInt *low, ConstantInt *high, BasicBlock *bb)
-          : Low(low), High(high), BB(bb) {}
-    };
-
-    using CaseVector = std::vector<CaseRange>;
-    using CaseItr = std::vector<CaseRange>::iterator;
-
-  private:
-    void processSwitchInst(SwitchInst *SI, SmallPtrSetImpl<BasicBlock*> &DeleteList);
-
-    BasicBlock *switchConvert(CaseItr Begin, CaseItr End,
-                              ConstantInt *LowerBound, ConstantInt *UpperBound,
-                              Value *Val, BasicBlock *Predecessor,
-                              BasicBlock *OrigBlock, BasicBlock *Default,
-                              const std::vector<IntRange> &UnreachableRanges);
-    BasicBlock *newLeafBlock(CaseRange &Leaf, Value *Val, BasicBlock *OrigBlock,
-                             BasicBlock *Default);
-    unsigned Clusterify(CaseVector &Cases, SwitchInst *SI);
-  };
-
-  /// The comparison function for sorting the switch case values in the vector.
-  /// WARNING: Case ranges should be disjoint!
-  struct CaseCmp {
-    bool operator()(const LowerSwitch::CaseRange& C1,
-                    const LowerSwitch::CaseRange& C2) {
-      const ConstantInt* CI1 = cast<const ConstantInt>(C1.Low);
-      const ConstantInt* CI2 = cast<const ConstantInt>(C2.High);
-      return CI1->getValue().slt(CI2->getValue());
-    }
-  };
-
-} // end anonymous namespace
-
-char LowerSwitch::ID = 0;
-
-// Publicly exposed interface to pass...
-char &llvm::LowerSwitchID = LowerSwitch::ID;
-
-INITIALIZE_PASS(LowerSwitch, "lowerswitch",
-                "Lower SwitchInst's to branches", false, false)
-
-// createLowerSwitchPass - Interface to this file...
-FunctionPass *llvm::createLowerSwitchPass() {
-  return new LowerSwitch();
-}
-
-bool LowerSwitch::runOnFunction(Function &F) {
-  bool Changed = false;
-  SmallPtrSet<BasicBlock*, 8> DeleteList;
-
-  for (Function::iterator I = F.begin(), E = F.end(); I != E; ) {
-    BasicBlock *Cur = &*I++; // Advance over block so we don't traverse new blocks
-
-    // If the block is a dead Default block that will be deleted later, don't
-    // waste time processing it.
-    if (DeleteList.count(Cur))
-      continue;
-
-    if (SwitchInst *SI = dyn_cast<SwitchInst>(Cur->getTerminator())) {
-      Changed = true;
-      processSwitchInst(SI, DeleteList);
-    }
-  }
-
-  for (BasicBlock* BB: DeleteList) {
-    DeleteDeadBlock(BB);
-  }
-
-  return Changed;
-}
-
-/// Used for debugging purposes.
-LLVM_ATTRIBUTE_USED
-static raw_ostream &operator<<(raw_ostream &O,
-                               const LowerSwitch::CaseVector &C) {
-  O << "[";
-
-  for (LowerSwitch::CaseVector::const_iterator B = C.begin(),
-         E = C.end(); B != E; ) {
-    O << *B->Low << " -" << *B->High;
-    if (++B != E) O << ", ";
-  }
-
-  return O << "]";
-}
-
-/// Update the first occurrence of the "switch statement" BB in the PHI
-/// node with the "new" BB. The other occurrences will:
-///
-/// 1) Be updated by subsequent calls to this function.  Switch statements may
-/// have more than one outcoming edge into the same BB if they all have the same
-/// value. When the switch statement is converted these incoming edges are now
-/// coming from multiple BBs.
-/// 2) Removed if subsequent incoming values now share the same case, i.e.,
-/// multiple outcome edges are condensed into one. This is necessary to keep the
-/// number of phi values equal to the number of branches to SuccBB.
-static void fixPhis(BasicBlock *SuccBB, BasicBlock *OrigBB, BasicBlock *NewBB,
-                    unsigned NumMergedCases) {
-  for (BasicBlock::iterator I = SuccBB->begin(),
-                            IE = SuccBB->getFirstNonPHI()->getIterator();
-       I != IE; ++I) {
-    PHINode *PN = cast<PHINode>(I);
-
-    // Only update the first occurrence.
-    unsigned Idx = 0, E = PN->getNumIncomingValues();
-    unsigned LocalNumMergedCases = NumMergedCases;
-    for (; Idx != E; ++Idx) {
-      if (PN->getIncomingBlock(Idx) == OrigBB) {
-        PN->setIncomingBlock(Idx, NewBB);
-        break;
-      }
-    }
-
-    // Remove additional occurrences coming from condensed cases and keep the
-    // number of incoming values equal to the number of branches to SuccBB.
-    SmallVector<unsigned, 8> Indices;
-    for (++Idx; LocalNumMergedCases > 0 && Idx < E; ++Idx)
-      if (PN->getIncomingBlock(Idx) == OrigBB) {
-        Indices.push_back(Idx);
-        LocalNumMergedCases--;
-      }
-    // Remove incoming values in the reverse order to prevent invalidating
-    // *successive* index.
-    for (unsigned III : llvm::reverse(Indices))
-      PN->removeIncomingValue(III);
-  }
-}
-
-/// Convert the switch statement into a binary lookup of the case values.
-/// The function recursively builds this tree. LowerBound and UpperBound are
-/// used to keep track of the bounds for Val that have already been checked by
-/// a block emitted by one of the previous calls to switchConvert in the call
-/// stack.
-BasicBlock *
-LowerSwitch::switchConvert(CaseItr Begin, CaseItr End, ConstantInt *LowerBound,
-                           ConstantInt *UpperBound, Value *Val,
-                           BasicBlock *Predecessor, BasicBlock *OrigBlock,
-                           BasicBlock *Default,
-                           const std::vector<IntRange> &UnreachableRanges) {
-  unsigned Size = End - Begin;
-
-  if (Size == 1) {
-    // Check if the Case Range is perfectly squeezed in between
-    // already checked Upper and Lower bounds. If it is then we can avoid
-    // emitting the code that checks if the value actually falls in the range
-    // because the bounds already tell us so.
-    if (Begin->Low == LowerBound && Begin->High == UpperBound) {
-      unsigned NumMergedCases = 0;
-      if (LowerBound && UpperBound)
-        NumMergedCases =
-            UpperBound->getSExtValue() - LowerBound->getSExtValue();
-      fixPhis(Begin->BB, OrigBlock, Predecessor, NumMergedCases);
-      return Begin->BB;
-    }
-    return newLeafBlock(*Begin, Val, OrigBlock, Default);
-  }
-
-  unsigned Mid = Size / 2;
-  std::vector<CaseRange> LHS(Begin, Begin + Mid);
-  LLVM_DEBUG(dbgs() << "LHS: " << LHS << "\n");
-  std::vector<CaseRange> RHS(Begin + Mid, End);
-  LLVM_DEBUG(dbgs() << "RHS: " << RHS << "\n");
-
-  CaseRange &Pivot = *(Begin + Mid);
-  LLVM_DEBUG(dbgs() << "Pivot ==> " << Pivot.Low->getValue() << " -"
-                    << Pivot.High->getValue() << "\n");
-
-  // NewLowerBound here should never be the integer minimal value.
-  // This is because it is computed from a case range that is never
-  // the smallest, so there is always a case range that has at least
-  // a smaller value.
-  ConstantInt *NewLowerBound = Pivot.Low;
-
-  // Because NewLowerBound is never the smallest representable integer
-  // it is safe here to subtract one.
-  ConstantInt *NewUpperBound = ConstantInt::get(NewLowerBound->getContext(),
-                                                NewLowerBound->getValue() - 1);
-
-  if (!UnreachableRanges.empty()) {
-    // Check if the gap between LHS's highest and NewLowerBound is unreachable.
-    int64_t GapLow = LHS.back().High->getSExtValue() + 1;
-    int64_t GapHigh = NewLowerBound->getSExtValue() - 1;
-    IntRange Gap = { GapLow, GapHigh };
-    if (GapHigh >= GapLow && IsInRanges(Gap, UnreachableRanges))
-      NewUpperBound = LHS.back().High;
-  }
-
-  LLVM_DEBUG(dbgs() << "LHS Bounds ==> "; if (LowerBound) {
-    dbgs() << LowerBound->getSExtValue();
-  } else { dbgs() << "NONE"; } dbgs() << " - "
-                                      << NewUpperBound->getSExtValue() << "\n";
-             dbgs() << "RHS Bounds ==> ";
-             dbgs() << NewLowerBound->getSExtValue() << " - "; if (UpperBound) {
-               dbgs() << UpperBound->getSExtValue() << "\n";
-             } else { dbgs() << "NONE\n"; });
-
-  // Create a new node that checks if the value is < pivot. Go to the
-  // left branch if it is and right branch if not.
-  Function* F = OrigBlock->getParent();
-  BasicBlock* NewNode = BasicBlock::Create(Val->getContext(), "NodeBlock");
-
-  ICmpInst* Comp = new ICmpInst(ICmpInst::ICMP_SLT,
-                                Val, Pivot.Low, "Pivot");
-
-  BasicBlock *LBranch = switchConvert(LHS.begin(), LHS.end(), LowerBound,
-                                      NewUpperBound, Val, NewNode, OrigBlock,
-                                      Default, UnreachableRanges);
-  BasicBlock *RBranch = switchConvert(RHS.begin(), RHS.end(), NewLowerBound,
-                                      UpperBound, Val, NewNode, OrigBlock,
-                                      Default, UnreachableRanges);
-
-  F->getBasicBlockList().insert(++OrigBlock->getIterator(), NewNode);
-  NewNode->getInstList().push_back(Comp);
-
-  BranchInst::Create(LBranch, RBranch, Comp, NewNode);
-  return NewNode;
-}
-
-/// Create a new leaf block for the binary lookup tree. It checks if the
-/// switch's value == the case's value. If not, then it jumps to the default
-/// branch. At this point in the tree, the value can't be another valid case
-/// value, so the jump to the "default" branch is warranted.
-BasicBlock* LowerSwitch::newLeafBlock(CaseRange& Leaf, Value* Val,
-                                      BasicBlock* OrigBlock,
-                                      BasicBlock* Default) {
-  Function* F = OrigBlock->getParent();
-  BasicBlock* NewLeaf = BasicBlock::Create(Val->getContext(), "LeafBlock");
-  F->getBasicBlockList().insert(++OrigBlock->getIterator(), NewLeaf);
-
-  // Emit comparison
-  ICmpInst* Comp = nullptr;
-  if (Leaf.Low == Leaf.High) {
-    // Make the seteq instruction...
-    Comp = new ICmpInst(*NewLeaf, ICmpInst::ICMP_EQ, Val,
-                        Leaf.Low, "SwitchLeaf");
-  } else {
-    // Make range comparison
-    if (Leaf.Low->isMinValue(true /*isSigned*/)) {
-      // Val >= Min && Val <= Hi --> Val <= Hi
-      Comp = new ICmpInst(*NewLeaf, ICmpInst::ICMP_SLE, Val, Leaf.High,
-                          "SwitchLeaf");
-    } else if (Leaf.Low->isZero()) {
-      // Val >= 0 && Val <= Hi --> Val <=u Hi
-      Comp = new ICmpInst(*NewLeaf, ICmpInst::ICMP_ULE, Val, Leaf.High,
-                          "SwitchLeaf");
-    } else {
-      // Emit V-Lo <=u Hi-Lo
-      Constant* NegLo = ConstantExpr::getNeg(Leaf.Low);
-      Instruction* Add = BinaryOperator::CreateAdd(Val, NegLo,
-                                                   Val->getName()+".off",
-                                                   NewLeaf);
-      Constant *UpperBound = ConstantExpr::getAdd(NegLo, Leaf.High);
-      Comp = new ICmpInst(*NewLeaf, ICmpInst::ICMP_ULE, Add, UpperBound,
-                          "SwitchLeaf");
-    }
-  }
-
-  // Make the conditional branch...
-  BasicBlock* Succ = Leaf.BB;
-  BranchInst::Create(Succ, Default, Comp, NewLeaf);
-
-  // If there were any PHI nodes in this successor, rewrite one entry
-  // from OrigBlock to come from NewLeaf.
-  for (BasicBlock::iterator I = Succ->begin(); isa<PHINode>(I); ++I) {
-    PHINode* PN = cast<PHINode>(I);
-    // Remove all but one incoming entries from the cluster
-    uint64_t Range = Leaf.High->getSExtValue() -
-                     Leaf.Low->getSExtValue();
-    for (uint64_t j = 0; j < Range; ++j) {
-      PN->removeIncomingValue(OrigBlock);
-    }
-
-    int BlockIdx = PN->getBasicBlockIndex(OrigBlock);
-    assert(BlockIdx != -1 && "Switch didn't go to this successor??");
-    PN->setIncomingBlock((unsigned)BlockIdx, NewLeaf);
-  }
-
-  return NewLeaf;
-}
-
-/// Transform simple list of Cases into list of CaseRange's.
-unsigned LowerSwitch::Clusterify(CaseVector& Cases, SwitchInst *SI) {
-  unsigned numCmps = 0;
-
-  // Start with "simple" cases
-  for (auto Case : SI->cases())
-    Cases.push_back(CaseRange(Case.getCaseValue(), Case.getCaseValue(),
-                              Case.getCaseSuccessor()));
-
-  llvm::sort(Cases, CaseCmp());
-
-  // Merge case into clusters
-  if (Cases.size() >= 2) {
-    CaseItr I = Cases.begin();
-    for (CaseItr J = std::next(I), E = Cases.end(); J != E; ++J) {
-      int64_t nextValue = J->Low->getSExtValue();
-      int64_t currentValue = I->High->getSExtValue();
-      BasicBlock* nextBB = J->BB;
-      BasicBlock* currentBB = I->BB;
-
-      // If the two neighboring cases go to the same destination, merge them
-      // into a single case.
-      assert(nextValue > currentValue && "Cases should be strictly ascending");
-      if ((nextValue == currentValue + 1) && (currentBB == nextBB)) {
-        I->High = J->High;
-        // FIXME: Combine branch weights.
-      } else if (++I != J) {
-        *I = *J;
-      }
-    }
-    Cases.erase(std::next(I), Cases.end());
-  }
-
-  for (CaseItr I=Cases.begin(), E=Cases.end(); I!=E; ++I, ++numCmps) {
-    if (I->Low != I->High)
-      // A range counts double, since it requires two compares.
-      ++numCmps;
-  }
-
-  return numCmps;
-}
-
-/// Replace the specified switch instruction with a sequence of chained if-then
-/// insts in a balanced binary search.
-void LowerSwitch::processSwitchInst(SwitchInst *SI,
-                                    SmallPtrSetImpl<BasicBlock*> &DeleteList) {
-  BasicBlock *CurBlock = SI->getParent();
-  BasicBlock *OrigBlock = CurBlock;
-  Function *F = CurBlock->getParent();
-  Value *Val = SI->getCondition();  // The value we are switching on...
-  BasicBlock* Default = SI->getDefaultDest();
-
-  // Don't handle unreachable blocks. If there are successors with phis, this
-  // would leave them behind with missing predecessors.
-  if ((CurBlock != &F->getEntryBlock() && pred_empty(CurBlock)) ||
-      CurBlock->getSinglePredecessor() == CurBlock) {
-    DeleteList.insert(CurBlock);
-    return;
-  }
-
-  // If there is only the default destination, just branch.
-  if (!SI->getNumCases()) {
-    BranchInst::Create(Default, CurBlock);
-    SI->eraseFromParent();
-    return;
-  }
-
-  // Prepare cases vector.
-  CaseVector Cases;
-  unsigned numCmps = Clusterify(Cases, SI);
-  LLVM_DEBUG(dbgs() << "Clusterify finished. Total clusters: " << Cases.size()
-                    << ". Total compares: " << numCmps << "\n");
-  LLVM_DEBUG(dbgs() << "Cases: " << Cases << "\n");
-  (void)numCmps;
-
-  ConstantInt *LowerBound = nullptr;
-  ConstantInt *UpperBound = nullptr;
-  std::vector<IntRange> UnreachableRanges;
-
-  if (isa<UnreachableInst>(Default->getFirstNonPHIOrDbg())) {
-    // Make the bounds tightly fitted around the case value range, because we
-    // know that the value passed to the switch must be exactly one of the case
-    // values.
-    assert(!Cases.empty());
-    LowerBound = Cases.front().Low;
-    UpperBound = Cases.back().High;
-
-    DenseMap<BasicBlock *, unsigned> Popularity;
-    unsigned MaxPop = 0;
-    BasicBlock *PopSucc = nullptr;
-
-    IntRange R = {std::numeric_limits<int64_t>::min(),
-                  std::numeric_limits<int64_t>::max()};
-    UnreachableRanges.push_back(R);
-    for (const auto &I : Cases) {
-      int64_t Low = I.Low->getSExtValue();
-      int64_t High = I.High->getSExtValue();
-
-      IntRange &LastRange = UnreachableRanges.back();
-      if (LastRange.Low == Low) {
-        // There is nothing left of the previous range.
-        UnreachableRanges.pop_back();
-      } else {
-        // Terminate the previous range.
-        assert(Low > LastRange.Low);
-        LastRange.High = Low - 1;
-      }
-      if (High != std::numeric_limits<int64_t>::max()) {
-        IntRange R = { High + 1, std::numeric_limits<int64_t>::max() };
-        UnreachableRanges.push_back(R);
-      }
-
-      // Count popularity.
-      int64_t N = High - Low + 1;
-      unsigned &Pop = Popularity[I.BB];
-      if ((Pop += N) > MaxPop) {
-        MaxPop = Pop;
-        PopSucc = I.BB;
-      }
-    }
-#ifndef NDEBUG
-    /* UnreachableRanges should be sorted and the ranges non-adjacent. */
-    for (auto I = UnreachableRanges.begin(), E = UnreachableRanges.end();
-         I != E; ++I) {
-      assert(I->Low <= I->High);
-      auto Next = I + 1;
-      if (Next != E) {
-        assert(Next->Low > I->High);
-      }
-    }
-#endif
-
-    // As the default block in the switch is unreachable, update the PHI nodes
-    // (remove the entry to the default block) to reflect this.
-    Default->removePredecessor(OrigBlock);
-
-    // Use the most popular block as the new default, reducing the number of
-    // cases.
-    assert(MaxPop > 0 && PopSucc);
-    Default = PopSucc;
-    Cases.erase(
-        llvm::remove_if(
-            Cases, [PopSucc](const CaseRange &R) { return R.BB == PopSucc; }),
-        Cases.end());
-
-    // If there are no cases left, just branch.
-    if (Cases.empty()) {
-      BranchInst::Create(Default, CurBlock);
-      SI->eraseFromParent();
-      // As all the cases have been replaced with a single branch, only keep
-      // one entry in the PHI nodes.
-      for (unsigned I = 0 ; I < (MaxPop - 1) ; ++I)
-        PopSucc->removePredecessor(OrigBlock);
-      return;
-    }
-  }
-
-  unsigned NrOfDefaults = (SI->getDefaultDest() == Default) ? 1 : 0;
-  for (const auto &Case : SI->cases())
-    if (Case.getCaseSuccessor() == Default)
-      NrOfDefaults++;
-
-  // Create a new, empty default block so that the new hierarchy of
-  // if-then statements go to this and the PHI nodes are happy.
-  BasicBlock *NewDefault = BasicBlock::Create(SI->getContext(), "NewDefault");
-  F->getBasicBlockList().insert(Default->getIterator(), NewDefault);
-  BranchInst::Create(Default, NewDefault);
-
-  BasicBlock *SwitchBlock =
-      switchConvert(Cases.begin(), Cases.end(), LowerBound, UpperBound, Val,
-                    OrigBlock, OrigBlock, NewDefault, UnreachableRanges);
-
-  // If there are entries in any PHI nodes for the default edge, make sure
-  // to update them as well.
-  fixPhis(Default, OrigBlock, NewDefault, NrOfDefaults);
-
-  // Branch to our shiny new if-then stuff...
-  BranchInst::Create(SwitchBlock, OrigBlock);
-
-  // We are now done with the switch instruction, delete it.
-  BasicBlock *OldDefault = SI->getDefaultDest();
-  CurBlock->getInstList().erase(SI);
-
-  // If the Default block has no more predecessors just add it to DeleteList.
-  if (pred_begin(OldDefault) == pred_end(OldDefault))
-    DeleteList.insert(OldDefault);
-}