Move StructurizeCFG out of R600 to generic Transforms.

Register it with PassManager

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@184343 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 1 insertions, 898 deletions

diff --git a/lib/Target/R600/AMDGPUStructurizeCFG.cpp b/lib/Target/R600/AMDGPUStructurizeCFG.cpp
deleted file mode 100644
index d26783d..0000000
--- a/lib/Target/R600/AMDGPUStructurizeCFG.cpp
+++ /dev/null
@@ -1,896 +0,0 @@
-//===-- AMDGPUStructurizeCFG.cpp -  ------------------===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-/// \file
-/// The pass implemented in this file transforms the programs control flow
-/// graph into a form that's suitable for code generation on hardware that
-/// implements control flow by execution masking. This currently includes all
-/// AMD GPUs but may as well be useful for other types of hardware.
-//
-//===----------------------------------------------------------------------===//
-
-#include "AMDGPU.h"
-#include "llvm/ADT/MapVector.h"
-#include "llvm/ADT/SCCIterator.h"
-#include "llvm/Analysis/RegionInfo.h"
-#include "llvm/Analysis/RegionIterator.h"
-#include "llvm/Analysis/RegionPass.h"
-#include "llvm/IR/Module.h"
-#include "llvm/Support/PatternMatch.h"
-#include "llvm/Transforms/Utils/SSAUpdater.h"
-
-using namespace llvm;
-using namespace llvm::PatternMatch;
-
-namespace {
-
-// Definition of the complex types used in this pass.
-
-typedef std::pair<BasicBlock *, Value *> BBValuePair;
-
-typedef SmallVector<RegionNode*, 8> RNVector;
-typedef SmallVector<BasicBlock*, 8> BBVector;
-typedef SmallVector<BranchInst*, 8> BranchVector;
-typedef SmallVector<BBValuePair, 2> BBValueVector;
-
-typedef SmallPtrSet<BasicBlock *, 8> BBSet;
-
-typedef MapVector<PHINode *, BBValueVector> PhiMap;
-typedef MapVector<BasicBlock *, BBVector> BB2BBVecMap;
-
-typedef DenseMap<DomTreeNode *, unsigned> DTN2UnsignedMap;
-typedef DenseMap<BasicBlock *, PhiMap> BBPhiMap;
-typedef DenseMap<BasicBlock *, Value *> BBPredicates;
-typedef DenseMap<BasicBlock *, BBPredicates> PredMap;
-typedef DenseMap<BasicBlock *, BasicBlock*> BB2BBMap;
-
-// The name for newly created blocks.
-
-static const char *FlowBlockName = "Flow";
-
-/// @brief Find the nearest common dominator for multiple BasicBlocks
-///
-/// Helper class for AMDGPUStructurizeCFG
-/// TODO: Maybe move into common code
-class NearestCommonDominator {
-
-  DominatorTree *DT;
-
-  DTN2UnsignedMap IndexMap;
-
-  BasicBlock *Result;
-  unsigned ResultIndex;
-  bool ExplicitMentioned;
-
-public:
-  /// \brief Start a new query
-  NearestCommonDominator(DominatorTree *DomTree) {
-    DT = DomTree;
-    Result = 0;
-  }
-
-  /// \brief Add BB to the resulting dominator
-  void addBlock(BasicBlock *BB, bool Remember = true) {
-
-    DomTreeNode *Node = DT->getNode(BB);
-
-    if (Result == 0) {
-      unsigned Numbering = 0;
-      for (;Node;Node = Node->getIDom())
-        IndexMap[Node] = ++Numbering;
-      Result = BB;
-      ResultIndex = 1;
-      ExplicitMentioned = Remember;
-      return;
-    }
-
-    for (;Node;Node = Node->getIDom())
-      if (IndexMap.count(Node))
-        break;
-      else
-        IndexMap[Node] = 0;
-
-    assert(Node && "Dominator tree invalid!");
-
-    unsigned Numbering = IndexMap[Node];
-    if (Numbering > ResultIndex) {
-      Result = Node->getBlock();
-      ResultIndex = Numbering;
-      ExplicitMentioned = Remember && (Result == BB);
-    } else if (Numbering == ResultIndex) {
-      ExplicitMentioned |= Remember;
-    }
-  }
-
-  /// \brief Is "Result" one of the BBs added with "Remember" = True?
-  bool wasResultExplicitMentioned() {
-    return ExplicitMentioned;
-  }
-
-  /// \brief Get the query result
-  BasicBlock *getResult() {
-    return Result;
-  }
-};
-
-/// @brief Transforms the control flow graph on one single entry/exit region
-/// at a time.
-///
-/// After the transform all "If"/"Then"/"Else" style control flow looks like
-/// this:
-///
-/// \verbatim
-/// 1
-/// ||
-/// | |
-/// 2 |
-/// | /
-/// |/   
-/// 3
-/// ||   Where:
-/// | |  1 = "If" block, calculates the condition
-/// 4 |  2 = "Then" subregion, runs if the condition is true
-/// | /  3 = "Flow" blocks, newly inserted flow blocks, rejoins the flow
-/// |/   4 = "Else" optional subregion, runs if the condition is false
-/// 5    5 = "End" block, also rejoins the control flow
-/// \endverbatim
-///
-/// Control flow is expressed as a branch where the true exit goes into the
-/// "Then"/"Else" region, while the false exit skips the region
-/// The condition for the optional "Else" region is expressed as a PHI node.
-/// The incomming values of the PHI node are true for the "If" edge and false
-/// for the "Then" edge.
-///
-/// Additionally to that even complicated loops look like this:
-///
-/// \verbatim
-/// 1
-/// ||
-/// | |
-/// 2 ^  Where:
-/// | /  1 = "Entry" block
-/// |/   2 = "Loop" optional subregion, with all exits at "Flow" block
-/// 3    3 = "Flow" block, with back edge to entry block
-/// |
-/// \endverbatim
-///
-/// The back edge of the "Flow" block is always on the false side of the branch
-/// while the true side continues the general flow. So the loop condition
-/// consist of a network of PHI nodes where the true incoming values expresses
-/// breaks and the false values expresses continue states.
-class AMDGPUStructurizeCFG : public RegionPass {
-
-  static char ID;
-
-  Type *Boolean;
-  ConstantInt *BoolTrue;
-  ConstantInt *BoolFalse;
-  UndefValue *BoolUndef;
-
-  Function *Func;
-  Region *ParentRegion;
-
-  DominatorTree *DT;
-
-  RNVector Order;
-  BBSet Visited;
-
-  BBPhiMap DeletedPhis;
-  BB2BBVecMap AddedPhis;
-
-  PredMap Predicates;
-  BranchVector Conditions;
-
-  BB2BBMap Loops;
-  PredMap LoopPreds;
-  BranchVector LoopConds;
-
-  RegionNode *PrevNode;
-
-  void orderNodes();
-
-  void analyzeLoops(RegionNode *N);
-
-  Value *invert(Value *Condition);
-
-  Value *buildCondition(BranchInst *Term, unsigned Idx, bool Invert);
-
-  void gatherPredicates(RegionNode *N);
-
-  void collectInfos();
-
-  void insertConditions(bool Loops);
-
-  void delPhiValues(BasicBlock *From, BasicBlock *To);
-
-  void addPhiValues(BasicBlock *From, BasicBlock *To);
-
-  void setPhiValues();
-
-  void killTerminator(BasicBlock *BB);
-
-  void changeExit(RegionNode *Node, BasicBlock *NewExit,
-                  bool IncludeDominator);
-
-  BasicBlock *getNextFlow(BasicBlock *Dominator);
-
-  BasicBlock *needPrefix(bool NeedEmpty);
-
-  BasicBlock *needPostfix(BasicBlock *Flow, bool ExitUseAllowed);
-
-  void setPrevNode(BasicBlock *BB);
-
-  bool dominatesPredicates(BasicBlock *BB, RegionNode *Node);
-
-  bool isPredictableTrue(RegionNode *Node);
-
-  void wireFlow(bool ExitUseAllowed, BasicBlock *LoopEnd);
-
-  void handleLoops(bool ExitUseAllowed, BasicBlock *LoopEnd);
-
-  void createFlow();
-
-  void rebuildSSA();
-
-public:
-  AMDGPUStructurizeCFG():
-    RegionPass(ID) {
-
-    initializeRegionInfoPass(*PassRegistry::getPassRegistry());
-  }
-
-  using Pass::doInitialization;
-  virtual bool doInitialization(Region *R, RGPassManager &RGM);
-
-  virtual bool runOnRegion(Region *R, RGPassManager &RGM);
-
-  virtual const char *getPassName() const {
-    return "AMDGPU simplify control flow";
-  }
-
-  void getAnalysisUsage(AnalysisUsage &AU) const {
-
-    AU.addRequired<DominatorTree>();
-    AU.addPreserved<DominatorTree>();
-    RegionPass::getAnalysisUsage(AU);
-  }
-
-};
-
-} // end anonymous namespace
-
-char AMDGPUStructurizeCFG::ID = 0;
-
-/// \brief Initialize the types and constants used in the pass
-bool AMDGPUStructurizeCFG::doInitialization(Region *R, RGPassManager &RGM) {
-  LLVMContext &Context = R->getEntry()->getContext();
-
-  Boolean = Type::getInt1Ty(Context);
-  BoolTrue = ConstantInt::getTrue(Context);
-  BoolFalse = ConstantInt::getFalse(Context);
-  BoolUndef = UndefValue::get(Boolean);
-
-  return false;
-}
-
-/// \brief Build up the general order of nodes
-void AMDGPUStructurizeCFG::orderNodes() {
-  scc_iterator<Region *> I = scc_begin(ParentRegion),
-                         E = scc_end(ParentRegion);
-  for (Order.clear(); I != E; ++I) {
-    std::vector<RegionNode *> &Nodes = *I;
-    Order.append(Nodes.begin(), Nodes.end());
-  }
-}
-
-/// \brief Determine the end of the loops
-void AMDGPUStructurizeCFG::analyzeLoops(RegionNode *N) {
-
-  if (N->isSubRegion()) {
-    // Test for exit as back edge
-    BasicBlock *Exit = N->getNodeAs<Region>()->getExit();
-    if (Visited.count(Exit))
-      Loops[Exit] = N->getEntry();
-
-  } else {
-    // Test for sucessors as back edge
-    BasicBlock *BB = N->getNodeAs<BasicBlock>();
-    BranchInst *Term = cast<BranchInst>(BB->getTerminator());
-
-    for (unsigned i = 0, e = Term->getNumSuccessors(); i != e; ++i) {
-      BasicBlock *Succ = Term->getSuccessor(i);
-
-      if (Visited.count(Succ))
-        Loops[Succ] = BB;
-    }
-  }
-}
-
-/// \brief Invert the given condition
-Value *AMDGPUStructurizeCFG::invert(Value *Condition) {
-
-  // First: Check if it's a constant
-  if (Condition == BoolTrue)
-    return BoolFalse;
-
-  if (Condition == BoolFalse)
-    return BoolTrue;
-
-  if (Condition == BoolUndef)
-    return BoolUndef;
-
-  // Second: If the condition is already inverted, return the original value
-  if (match(Condition, m_Not(m_Value(Condition))))
-    return Condition;
-
-  // Third: Check all the users for an invert
-  BasicBlock *Parent = cast<Instruction>(Condition)->getParent();
-  for (Value::use_iterator I = Condition->use_begin(),
-       E = Condition->use_end(); I != E; ++I) {
-
-    Instruction *User = dyn_cast<Instruction>(*I);
-    if (!User || User->getParent() != Parent)
-      continue;
-
-    if (match(*I, m_Not(m_Specific(Condition))))
-      return *I;
-  }
-
-  // Last option: Create a new instruction
-  return BinaryOperator::CreateNot(Condition, "", Parent->getTerminator());
-}
-
-/// \brief Build the condition for one edge
-Value *AMDGPUStructurizeCFG::buildCondition(BranchInst *Term, unsigned Idx,
-                                            bool Invert) {
-  Value *Cond = Invert ? BoolFalse : BoolTrue;
-  if (Term->isConditional()) {
-    Cond = Term->getCondition();
-
-    if (Idx != (unsigned)Invert)
-      Cond = invert(Cond);
-  }
-  return Cond;
-}
-
-/// \brief Analyze the predecessors of each block and build up predicates
-void AMDGPUStructurizeCFG::gatherPredicates(RegionNode *N) {
-
-  RegionInfo *RI = ParentRegion->getRegionInfo();
-  BasicBlock *BB = N->getEntry();
-  BBPredicates &Pred = Predicates[BB];
-  BBPredicates &LPred = LoopPreds[BB];
-
-  for (pred_iterator PI = pred_begin(BB), PE = pred_end(BB);
-       PI != PE; ++PI) {
-
-    // Ignore it if it's a branch from outside into our region entry
-    if (!ParentRegion->contains(*PI))
-      continue;
-
-    Region *R = RI->getRegionFor(*PI);
-    if (R == ParentRegion) {
-
-      // It's a top level block in our region
-      BranchInst *Term = cast<BranchInst>((*PI)->getTerminator());
-      for (unsigned i = 0, e = Term->getNumSuccessors(); i != e; ++i) {
-        BasicBlock *Succ = Term->getSuccessor(i);
-        if (Succ != BB)
-          continue;
-
-        if (Visited.count(*PI)) {
-          // Normal forward edge
-          if (Term->isConditional()) {
-            // Try to treat it like an ELSE block
-            BasicBlock *Other = Term->getSuccessor(!i);
-            if (Visited.count(Other) && !Loops.count(Other) &&
-                !Pred.count(Other) && !Pred.count(*PI)) {
-
-              Pred[Other] = BoolFalse;
-              Pred[*PI] = BoolTrue;
-              continue;
-            }
-          }
-          Pred[*PI] = buildCondition(Term, i, false);
- 
-        } else {
-          // Back edge
-          LPred[*PI] = buildCondition(Term, i, true);
-        }
-      }
-
-    } else {
-
-      // It's an exit from a sub region
-      while(R->getParent() != ParentRegion)
-        R = R->getParent();
-
-      // Edge from inside a subregion to its entry, ignore it
-      if (R == N)
-        continue;
-
-      BasicBlock *Entry = R->getEntry();
-      if (Visited.count(Entry))
-        Pred[Entry] = BoolTrue;
-      else
-        LPred[Entry] = BoolFalse;
-    }
-  }
-}
-
-/// \brief Collect various loop and predicate infos
-void AMDGPUStructurizeCFG::collectInfos() {
-
-  // Reset predicate
-  Predicates.clear();
-
-  // and loop infos
-  Loops.clear();
-  LoopPreds.clear();
-
-  // Reset the visited nodes
-  Visited.clear();
-
-  for (RNVector::reverse_iterator OI = Order.rbegin(), OE = Order.rend();
-       OI != OE; ++OI) {
-
-    // Analyze all the conditions leading to a node
-    gatherPredicates(*OI);
-
-    // Remember that we've seen this node
-    Visited.insert((*OI)->getEntry());
-
-    // Find the last back edges
-    analyzeLoops(*OI);
-  }
-}
-
-/// \brief Insert the missing branch conditions
-void AMDGPUStructurizeCFG::insertConditions(bool Loops) {
-  BranchVector &Conds = Loops ? LoopConds : Conditions;
-  Value *Default = Loops ? BoolTrue : BoolFalse;
-  SSAUpdater PhiInserter;
-
-  for (BranchVector::iterator I = Conds.begin(),
-       E = Conds.end(); I != E; ++I) {
-
-    BranchInst *Term = *I;
-    assert(Term->isConditional());
-
-    BasicBlock *Parent = Term->getParent();
-    BasicBlock *SuccTrue = Term->getSuccessor(0);
-    BasicBlock *SuccFalse = Term->getSuccessor(1);
-
-    PhiInserter.Initialize(Boolean, "");
-    PhiInserter.AddAvailableValue(&Func->getEntryBlock(), Default);
-    PhiInserter.AddAvailableValue(Loops ? SuccFalse : Parent, Default);
-
-    BBPredicates &Preds = Loops ? LoopPreds[SuccFalse] : Predicates[SuccTrue];
-
-    NearestCommonDominator Dominator(DT);
-    Dominator.addBlock(Parent, false);
-
-    Value *ParentValue = 0;
-    for (BBPredicates::iterator PI = Preds.begin(), PE = Preds.end();
-         PI != PE; ++PI) {
-
-      if (PI->first == Parent) {
-        ParentValue = PI->second;
-        break;
-      }
-      PhiInserter.AddAvailableValue(PI->first, PI->second);
-      Dominator.addBlock(PI->first);
-    }
-
-    if (ParentValue) {
-      Term->setCondition(ParentValue);
-    } else {
-      if (!Dominator.wasResultExplicitMentioned())
-        PhiInserter.AddAvailableValue(Dominator.getResult(), Default);
-
-      Term->setCondition(PhiInserter.GetValueInMiddleOfBlock(Parent));
-    }
-  }
-}
-
-/// \brief Remove all PHI values coming from "From" into "To" and remember
-/// them in DeletedPhis
-void AMDGPUStructurizeCFG::delPhiValues(BasicBlock *From, BasicBlock *To) {
-  PhiMap &Map = DeletedPhis[To];
-  for (BasicBlock::iterator I = To->begin(), E = To->end();
-       I != E && isa<PHINode>(*I);) {
-
-    PHINode &Phi = cast<PHINode>(*I++);
-    while (Phi.getBasicBlockIndex(From) != -1) {
-      Value *Deleted = Phi.removeIncomingValue(From, false);
-      Map[&Phi].push_back(std::make_pair(From, Deleted));
-    }
-  }
-}
-
-/// \brief Add a dummy PHI value as soon as we knew the new predecessor
-void AMDGPUStructurizeCFG::addPhiValues(BasicBlock *From, BasicBlock *To) {
-  for (BasicBlock::iterator I = To->begin(), E = To->end();
-       I != E && isa<PHINode>(*I);) {
-
-    PHINode &Phi = cast<PHINode>(*I++);
-    Value *Undef = UndefValue::get(Phi.getType());
-    Phi.addIncoming(Undef, From);
-  }
-  AddedPhis[To].push_back(From);
-}
-
-/// \brief Add the real PHI value as soon as everything is set up
-void AMDGPUStructurizeCFG::setPhiValues() {
-
-  SSAUpdater Updater;
-  for (BB2BBVecMap::iterator AI = AddedPhis.begin(), AE = AddedPhis.end();
-       AI != AE; ++AI) {
-
-    BasicBlock *To = AI->first;
-    BBVector &From = AI->second;
-
-    if (!DeletedPhis.count(To))
-      continue;
-
-    PhiMap &Map = DeletedPhis[To];
-    for (PhiMap::iterator PI = Map.begin(), PE = Map.end();
-         PI != PE; ++PI) {
-
-      PHINode *Phi = PI->first;
-      Value *Undef = UndefValue::get(Phi->getType());
-      Updater.Initialize(Phi->getType(), "");
-      Updater.AddAvailableValue(&Func->getEntryBlock(), Undef);
-      Updater.AddAvailableValue(To, Undef);
-
-      NearestCommonDominator Dominator(DT);
-      Dominator.addBlock(To, false);
-      for (BBValueVector::iterator VI = PI->second.begin(),
-           VE = PI->second.end(); VI != VE; ++VI) {
-
-        Updater.AddAvailableValue(VI->first, VI->second);
-        Dominator.addBlock(VI->first);
-      }
-
-      if (!Dominator.wasResultExplicitMentioned())
-        Updater.AddAvailableValue(Dominator.getResult(), Undef);
-
-      for (BBVector::iterator FI = From.begin(), FE = From.end();
-           FI != FE; ++FI) {
-
-        int Idx = Phi->getBasicBlockIndex(*FI);
-        assert(Idx != -1);
-        Phi->setIncomingValue(Idx, Updater.GetValueAtEndOfBlock(*FI));
-      }
-    }
-
-    DeletedPhis.erase(To);
-  }
-  assert(DeletedPhis.empty());
-}
-
-/// \brief Remove phi values from all successors and then remove the terminator.
-void AMDGPUStructurizeCFG::killTerminator(BasicBlock *BB) {
-  TerminatorInst *Term = BB->getTerminator();
-  if (!Term)
-    return;
-
-  for (succ_iterator SI = succ_begin(BB), SE = succ_end(BB);
-       SI != SE; ++SI) {
-
-    delPhiValues(BB, *SI);
-  }
-
-  Term->eraseFromParent();
-}
-
-/// \brief Let node exit(s) point to NewExit
-void AMDGPUStructurizeCFG::changeExit(RegionNode *Node, BasicBlock *NewExit,
-                                      bool IncludeDominator) {
-
-  if (Node->isSubRegion()) {
-    Region *SubRegion = Node->getNodeAs<Region>();
-    BasicBlock *OldExit = SubRegion->getExit();
-    BasicBlock *Dominator = 0;
-
-    // Find all the edges from the sub region to the exit
-    for (pred_iterator I = pred_begin(OldExit), E = pred_end(OldExit);
-         I != E;) {
-
-      BasicBlock *BB = *I++;
-      if (!SubRegion->contains(BB))
-        continue;
-
-      // Modify the edges to point to the new exit
-      delPhiValues(BB, OldExit);
-      BB->getTerminator()->replaceUsesOfWith(OldExit, NewExit);
-      addPhiValues(BB, NewExit);
-
-      // Find the new dominator (if requested)
-      if (IncludeDominator) {
-        if (!Dominator)
-          Dominator = BB;
-        else
-          Dominator = DT->findNearestCommonDominator(Dominator, BB);
-      }
-    }
-
-    // Change the dominator (if requested)
-    if (Dominator)
-      DT->changeImmediateDominator(NewExit, Dominator);
-
-    // Update the region info
-    SubRegion->replaceExit(NewExit);
-
-  } else {
-    BasicBlock *BB = Node->getNodeAs<BasicBlock>();
-    killTerminator(BB);
-    BranchInst::Create(NewExit, BB);
-    addPhiValues(BB, NewExit);
-    if (IncludeDominator)
-      DT->changeImmediateDominator(NewExit, BB);
-  }
-}
-
-/// \brief Create a new flow node and update dominator tree and region info
-BasicBlock *AMDGPUStructurizeCFG::getNextFlow(BasicBlock *Dominator) {
-  LLVMContext &Context = Func->getContext();
-  BasicBlock *Insert = Order.empty() ? ParentRegion->getExit() :
-                       Order.back()->getEntry();
-  BasicBlock *Flow = BasicBlock::Create(Context, FlowBlockName,
-                                        Func, Insert);
-  DT->addNewBlock(Flow, Dominator);
-  ParentRegion->getRegionInfo()->setRegionFor(Flow, ParentRegion);
-  return Flow;
-}
-
-/// \brief Create a new or reuse the previous node as flow node
-BasicBlock *AMDGPUStructurizeCFG::needPrefix(bool NeedEmpty) {
-
-  BasicBlock *Entry = PrevNode->getEntry();
-
-  if (!PrevNode->isSubRegion()) {
-    killTerminator(Entry);
-    if (!NeedEmpty || Entry->getFirstInsertionPt() == Entry->end())
-      return Entry;
-
-  } 
-
-  // create a new flow node
-  BasicBlock *Flow = getNextFlow(Entry);
-
-  // and wire it up
-  changeExit(PrevNode, Flow, true);
-  PrevNode = ParentRegion->getBBNode(Flow);
-  return Flow;
-}
-
-/// \brief Returns the region exit if possible, otherwise just a new flow node
-BasicBlock *AMDGPUStructurizeCFG::needPostfix(BasicBlock *Flow,
-                                              bool ExitUseAllowed) {
-
-  if (Order.empty() && ExitUseAllowed) {
-    BasicBlock *Exit = ParentRegion->getExit();
-    DT->changeImmediateDominator(Exit, Flow);
-    addPhiValues(Flow, Exit);
-    return Exit;
-  }
-  return getNextFlow(Flow);
-}
-
-/// \brief Set the previous node
-void AMDGPUStructurizeCFG::setPrevNode(BasicBlock *BB) {
-  PrevNode =  ParentRegion->contains(BB) ? ParentRegion->getBBNode(BB) : 0;
-}
-
-/// \brief Does BB dominate all the predicates of Node ?
-bool AMDGPUStructurizeCFG::dominatesPredicates(BasicBlock *BB, RegionNode *Node) {
-  BBPredicates &Preds = Predicates[Node->getEntry()];
-  for (BBPredicates::iterator PI = Preds.begin(), PE = Preds.end();
-       PI != PE; ++PI) {
-
-    if (!DT->dominates(BB, PI->first))
-      return false;
-  }
-  return true;
-}
-
-/// \brief Can we predict that this node will always be called?
-bool AMDGPUStructurizeCFG::isPredictableTrue(RegionNode *Node) {
-
-  BBPredicates &Preds = Predicates[Node->getEntry()];
-  bool Dominated = false;
-
-  // Regionentry is always true
-  if (PrevNode == 0)
-    return true;
-
-  for (BBPredicates::iterator I = Preds.begin(), E = Preds.end();
-       I != E; ++I) {
-
-    if (I->second != BoolTrue)
-      return false;
-
-    if (!Dominated && DT->dominates(I->first, PrevNode->getEntry()))
-      Dominated = true;
-  }
-
-  // TODO: The dominator check is too strict
-  return Dominated;
-}
-
-/// Take one node from the order vector and wire it up
-void AMDGPUStructurizeCFG::wireFlow(bool ExitUseAllowed,
-                                    BasicBlock *LoopEnd) {
-
-  RegionNode *Node = Order.pop_back_val();
-  Visited.insert(Node->getEntry());
-
-  if (isPredictableTrue(Node)) {
-    // Just a linear flow
-    if (PrevNode) {
-      changeExit(PrevNode, Node->getEntry(), true);
-    }
-    PrevNode = Node;
-
-  } else {
-    // Insert extra prefix node (or reuse last one)
-    BasicBlock *Flow = needPrefix(false);
-
-    // Insert extra postfix node (or use exit instead)
-    BasicBlock *Entry = Node->getEntry();
-    BasicBlock *Next = needPostfix(Flow, ExitUseAllowed);
-
-    // let it point to entry and next block
-    Conditions.push_back(BranchInst::Create(Entry, Next, BoolUndef, Flow));
-    addPhiValues(Flow, Entry);
-    DT->changeImmediateDominator(Entry, Flow);
-
-    PrevNode = Node;
-    while (!Order.empty() && !Visited.count(LoopEnd) &&
-           dominatesPredicates(Entry, Order.back())) {
-      handleLoops(false, LoopEnd);
-    }
-
-    changeExit(PrevNode, Next, false);
-    setPrevNode(Next);
-  }
-}
-
-void AMDGPUStructurizeCFG::handleLoops(bool ExitUseAllowed,
-                                       BasicBlock *LoopEnd) {
-  RegionNode *Node = Order.back();
-  BasicBlock *LoopStart = Node->getEntry();
-
-  if (!Loops.count(LoopStart)) {
-    wireFlow(ExitUseAllowed, LoopEnd);
-    return;
-  }
-
-  if (!isPredictableTrue(Node))
-    LoopStart = needPrefix(true);
-
-  LoopEnd = Loops[Node->getEntry()];
-  wireFlow(false, LoopEnd);
-  while (!Visited.count(LoopEnd)) {
-    handleLoops(false, LoopEnd);
-  }
-
-  // Create an extra loop end node
-  LoopEnd = needPrefix(false);
-  BasicBlock *Next = needPostfix(LoopEnd, ExitUseAllowed);
-  LoopConds.push_back(BranchInst::Create(Next, LoopStart,
-                                         BoolUndef, LoopEnd));
-  addPhiValues(LoopEnd, LoopStart);
-  setPrevNode(Next);
-}
-
-/// After this function control flow looks like it should be, but
-/// branches and PHI nodes only have undefined conditions.
-void AMDGPUStructurizeCFG::createFlow() {
-
-  BasicBlock *Exit = ParentRegion->getExit();
-  bool EntryDominatesExit = DT->dominates(ParentRegion->getEntry(), Exit);
-
-  DeletedPhis.clear();
-  AddedPhis.clear();
-  Conditions.clear();
-  LoopConds.clear();
-
-  PrevNode = 0;
-  Visited.clear();
-
-  while (!Order.empty()) {
-    handleLoops(EntryDominatesExit, 0);
-  }
-
-  if (PrevNode)
-    changeExit(PrevNode, Exit, EntryDominatesExit);
-  else
-    assert(EntryDominatesExit);
-}
-
-/// Handle a rare case where the disintegrated nodes instructions
-/// no longer dominate all their uses. Not sure if this is really nessasary
-void AMDGPUStructurizeCFG::rebuildSSA() {
-  SSAUpdater Updater;
-  for (Region::block_iterator I = ParentRegion->block_begin(),
-                              E = ParentRegion->block_end();
-       I != E; ++I) {
-
-    BasicBlock *BB = *I;
-    for (BasicBlock::iterator II = BB->begin(), IE = BB->end();
-         II != IE; ++II) {
-
-      bool Initialized = false;
-      for (Use *I = &II->use_begin().getUse(), *Next; I; I = Next) {
-
-        Next = I->getNext();
-
-        Instruction *User = cast<Instruction>(I->getUser());
-        if (User->getParent() == BB) {
-          continue;
-
-        } else if (PHINode *UserPN = dyn_cast<PHINode>(User)) {
-          if (UserPN->getIncomingBlock(*I) == BB)
-            continue;
-        }
-
-        if (DT->dominates(II, User))
-          continue;
-
-        if (!Initialized) {
-          Value *Undef = UndefValue::get(II->getType());
-          Updater.Initialize(II->getType(), "");
-          Updater.AddAvailableValue(&Func->getEntryBlock(), Undef);
-          Updater.AddAvailableValue(BB, II);
-          Initialized = true;
-        }
-        Updater.RewriteUseAfterInsertions(*I);
-      }
-    }
-  }
-}
-
-/// \brief Run the transformation for each region found
-bool AMDGPUStructurizeCFG::runOnRegion(Region *R, RGPassManager &RGM) {
-  if (R->isTopLevelRegion())
-    return false;
-
-  Func = R->getEntry()->getParent();
-  ParentRegion = R;
-
-  DT = &getAnalysis<DominatorTree>();
-
-  orderNodes();
-  collectInfos();
-  createFlow();
-  insertConditions(false);
-  insertConditions(true);
-  setPhiValues();
-  rebuildSSA();
-
-  // Cleanup
-  Order.clear();
-  Visited.clear();
-  DeletedPhis.clear();
-  AddedPhis.clear();
-  Predicates.clear();
-  Conditions.clear();
-  Loops.clear();
-  LoopPreds.clear();
-  LoopConds.clear();
-
-  return true;
-}
-
-/// \brief Create the pass
-Pass *llvm::createAMDGPUStructurizeCFGPass() {
-  return new AMDGPUStructurizeCFG();
-}
diff --git a/lib/Target/R600/AMDGPUTargetMachine.cpp b/lib/Target/R600/AMDGPUTargetMachine.cpp
index 2fba434..90f72de 100644
--- a/lib/Target/R600/AMDGPUTargetMachine.cpp
+++ b/lib/Target/R600/AMDGPUTargetMachine.cpp
@@ -109,7 +109,7 @@ bool
 AMDGPUPassConfig::addPreISel() {
   const AMDGPUSubtarget &ST = TM->getSubtarget<AMDGPUSubtarget>();
   if (ST.getGeneration() > AMDGPUSubtarget::NORTHERN_ISLANDS) {
-    addPass(createAMDGPUStructurizeCFGPass());
+    addPass(createStructurizeCFGPass());
     addPass(createSIAnnotateControlFlowPass());
   } else {
     addPass(createR600TextureIntrinsicsReplacer());
diff --git a/lib/Target/R600/CMakeLists.txt b/lib/Target/R600/CMakeLists.txt
index 1b79bf5..824475e 100644
--- a/lib/Target/R600/CMakeLists.txt
+++ b/lib/Target/R600/CMakeLists.txt
@@ -22,7 +22,6 @@ add_llvm_target(R600CodeGen
   AMDGPUMCInstLower.cpp
   AMDGPUMachineFunction.cpp
   AMDGPUSubtarget.cpp
-  AMDGPUStructurizeCFG.cpp
   AMDGPUTargetMachine.cpp
   AMDGPUISelLowering.cpp
   AMDGPUConvertToISA.cpp