Start the process of making MachineLoopInfo possible by templating Loop.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44097 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 0 insertions, 396 deletions

diff --git a/lib/Analysis/LoopInfo.cpp b/lib/Analysis/LoopInfo.cpp
index 09dca27..20ca892 100644
--- a/lib/Analysis/LoopInfo.cpp
+++ b/lib/Analysis/LoopInfo.cpp
@@ -34,69 +34,9 @@ X("loops", "Natural Loop Construction", true);
 //===----------------------------------------------------------------------===//
 // Loop implementation
 //
-bool Loop::contains(const BasicBlock *BB) const {
-  return std::find(Blocks.begin(), Blocks.end(), BB) != Blocks.end();
-}
-
-bool Loop::isLoopExit(const BasicBlock *BB) const {
-  for (succ_const_iterator SI = succ_begin(BB), SE = succ_end(BB);
-       SI != SE; ++SI) {
-    if (!contains(*SI))
-      return true;
-  }
-  return false;
-}
 
 /// getNumBackEdges - Calculate the number of back edges to the loop header.
 ///
-unsigned Loop::getNumBackEdges() const {
-  unsigned NumBackEdges = 0;
-  BasicBlock *H = getHeader();
-
-  for (pred_iterator I = pred_begin(H), E = pred_end(H); I != E; ++I)
-    if (contains(*I))
-      ++NumBackEdges;
-
-  return NumBackEdges;
-}
-
-/// isLoopInvariant - Return true if the specified value is loop invariant
-///
-bool Loop::isLoopInvariant(Value *V) const {
-  if (Instruction *I = dyn_cast<Instruction>(V))
-    return !contains(I->getParent());
-  return true;  // All non-instructions are loop invariant
-}
-
-void Loop::print(std::ostream &OS, unsigned Depth) const {
-  OS << std::string(Depth*2, ' ') << "Loop Containing: ";
-
-  for (unsigned i = 0; i < getBlocks().size(); ++i) {
-    if (i) OS << ",";
-    WriteAsOperand(OS, getBlocks()[i], false);
-  }
-  OS << "\n";
-
-  for (iterator I = begin(), E = end(); I != E; ++I)
-    (*I)->print(OS, Depth+2);
-}
-
-/// verifyLoop - Verify loop structure
-void Loop::verifyLoop() const {
-#ifndef NDEBUG
-  assert (getHeader() && "Loop header is missing");
-  assert (getLoopPreheader() && "Loop preheader is missing");
-  assert (getLoopLatch() && "Loop latch is missing");
-  for (std::vector<Loop*>::const_iterator I = SubLoops.begin(), E = SubLoops.end();
-       I != E; ++I)
-    (*I)->verifyLoop();
-#endif
-}
-
-void Loop::dump() const {
-  print(cerr);
-}
-
 
 //===----------------------------------------------------------------------===//
 // LoopInfo implementation
@@ -341,341 +281,5 @@ void LoopInfo::removeBlock(BasicBlock *BB) {
   }
 }
 
-
-//===----------------------------------------------------------------------===//
-// APIs for simple analysis of the loop.
-//
-
-/// getExitingBlocks - Return all blocks inside the loop that have successors
-/// outside of the loop.  These are the blocks _inside of the current loop_
-/// which branch out.  The returned list is always unique.
-///
-void Loop::getExitingBlocks(SmallVectorImpl<BasicBlock*> &ExitingBlocks) const {
-  // Sort the blocks vector so that we can use binary search to do quick
-  // lookups.
-  SmallVector<BasicBlock*, 128> LoopBBs(block_begin(), block_end());
-  std::sort(LoopBBs.begin(), LoopBBs.end());
-  
-  for (std::vector<BasicBlock*>::const_iterator BI = Blocks.begin(),
-       BE = Blocks.end(); BI != BE; ++BI)
-    for (succ_iterator I = succ_begin(*BI), E = succ_end(*BI); I != E; ++I)
-      if (!std::binary_search(LoopBBs.begin(), LoopBBs.end(), *I)) {
-        // Not in current loop? It must be an exit block.
-        ExitingBlocks.push_back(*BI);
-        break;
-      }
-}
-
-/// getExitBlocks - Return all of the successor blocks of this loop.  These
-/// are the blocks _outside of the current loop_ which are branched to.
-///
-void Loop::getExitBlocks(SmallVectorImpl<BasicBlock*> &ExitBlocks) const {
-  // Sort the blocks vector so that we can use binary search to do quick
-  // lookups.
-  SmallVector<BasicBlock*, 128> LoopBBs(block_begin(), block_end());
-  std::sort(LoopBBs.begin(), LoopBBs.end());
-  
-  for (std::vector<BasicBlock*>::const_iterator BI = Blocks.begin(),
-       BE = Blocks.end(); BI != BE; ++BI)
-    for (succ_iterator I = succ_begin(*BI), E = succ_end(*BI); I != E; ++I)
-      if (!std::binary_search(LoopBBs.begin(), LoopBBs.end(), *I))
-        // Not in current loop? It must be an exit block.
-        ExitBlocks.push_back(*I);
-}
-
-/// getUniqueExitBlocks - Return all unique successor blocks of this loop. These
-/// are the blocks _outside of the current loop_ which are branched to. This
-/// assumes that loop is in canonical form.
-//
-void Loop::getUniqueExitBlocks(SmallVectorImpl<BasicBlock*> &ExitBlocks) const {
-  // Sort the blocks vector so that we can use binary search to do quick
-  // lookups.
-  SmallVector<BasicBlock*, 128> LoopBBs(block_begin(), block_end());
-  std::sort(LoopBBs.begin(), LoopBBs.end());
-
-  std::vector<BasicBlock*> switchExitBlocks;  
-  
-  for (std::vector<BasicBlock*>::const_iterator BI = Blocks.begin(),
-    BE = Blocks.end(); BI != BE; ++BI) {
-
-    BasicBlock *current = *BI;
-    switchExitBlocks.clear();
-
-    for (succ_iterator I = succ_begin(*BI), E = succ_end(*BI); I != E; ++I) {
-      if (std::binary_search(LoopBBs.begin(), LoopBBs.end(), *I))
-    // If block is inside the loop then it is not a exit block.
-        continue;
-
-      pred_iterator PI = pred_begin(*I);
-      BasicBlock *firstPred = *PI;
-
-      // If current basic block is this exit block's first predecessor
-      // then only insert exit block in to the output ExitBlocks vector.
-      // This ensures that same exit block is not inserted twice into
-      // ExitBlocks vector.
-      if (current != firstPred) 
-        continue;
-
-      // If a terminator has more then two successors, for example SwitchInst,
-      // then it is possible that there are multiple edges from current block 
-      // to one exit block. 
-      if (current->getTerminator()->getNumSuccessors() <= 2) {
-        ExitBlocks.push_back(*I);
-        continue;
-      }
-      
-      // In case of multiple edges from current block to exit block, collect
-      // only one edge in ExitBlocks. Use switchExitBlocks to keep track of
-      // duplicate edges.
-      if (std::find(switchExitBlocks.begin(), switchExitBlocks.end(), *I) 
-          == switchExitBlocks.end()) {
-        switchExitBlocks.push_back(*I);
-        ExitBlocks.push_back(*I);
-      }
-    }
-  }
-}
-
-
-/// getLoopPreheader - If there is a preheader for this loop, return it.  A
-/// loop has a preheader if there is only one edge to the header of the loop
-/// from outside of the loop.  If this is the case, the block branching to the
-/// header of the loop is the preheader node.
-///
-/// This method returns null if there is no preheader for the loop.
-///
-BasicBlock *Loop::getLoopPreheader() const {
-  // Keep track of nodes outside the loop branching to the header...
-  BasicBlock *Out = 0;
-
-  // Loop over the predecessors of the header node...
-  BasicBlock *Header = getHeader();
-  for (pred_iterator PI = pred_begin(Header), PE = pred_end(Header);
-       PI != PE; ++PI)
-    if (!contains(*PI)) {     // If the block is not in the loop...
-      if (Out && Out != *PI)
-        return 0;             // Multiple predecessors outside the loop
-      Out = *PI;
-    }
-
-  // Make sure there is only one exit out of the preheader.
-  assert(Out && "Header of loop has no predecessors from outside loop?");
-  succ_iterator SI = succ_begin(Out);
-  ++SI;
-  if (SI != succ_end(Out))
-    return 0;  // Multiple exits from the block, must not be a preheader.
-
-  // If there is exactly one preheader, return it.  If there was zero, then Out
-  // is still null.
-  return Out;
-}
-
-/// getLoopLatch - If there is a latch block for this loop, return it.  A
-/// latch block is the canonical backedge for a loop.  A loop header in normal
-/// form has two edges into it: one from a preheader and one from a latch
-/// block.
-BasicBlock *Loop::getLoopLatch() const {
-  BasicBlock *Header = getHeader();
-  pred_iterator PI = pred_begin(Header), PE = pred_end(Header);
-  if (PI == PE) return 0;  // no preds?
-  
-  BasicBlock *Latch = 0;
-  if (contains(*PI))
-    Latch = *PI;
-  ++PI;
-  if (PI == PE) return 0;  // only one pred?
-  
-  if (contains(*PI)) {
-    if (Latch) return 0;  // multiple backedges
-    Latch = *PI;
-  }
-  ++PI;
-  if (PI != PE) return 0;  // more than two preds
-  
-  return Latch;  
-}
-
-/// getCanonicalInductionVariable - Check to see if the loop has a canonical
-/// induction variable: an integer recurrence that starts at 0 and increments by
-/// one each time through the loop.  If so, return the phi node that corresponds
-/// to it.
-///
-PHINode *Loop::getCanonicalInductionVariable() const {
-  BasicBlock *H = getHeader();
-
-  BasicBlock *Incoming = 0, *Backedge = 0;
-  pred_iterator PI = pred_begin(H);
-  assert(PI != pred_end(H) && "Loop must have at least one backedge!");
-  Backedge = *PI++;
-  if (PI == pred_end(H)) return 0;  // dead loop
-  Incoming = *PI++;
-  if (PI != pred_end(H)) return 0;  // multiple backedges?
-
-  if (contains(Incoming)) {
-    if (contains(Backedge))
-      return 0;
-    std::swap(Incoming, Backedge);
-  } else if (!contains(Backedge))
-    return 0;
-
-  // Loop over all of the PHI nodes, looking for a canonical indvar.
-  for (BasicBlock::iterator I = H->begin(); isa<PHINode>(I); ++I) {
-    PHINode *PN = cast<PHINode>(I);
-    if (Instruction *Inc =
-        dyn_cast<Instruction>(PN->getIncomingValueForBlock(Backedge)))
-      if (Inc->getOpcode() == Instruction::Add && Inc->getOperand(0) == PN)
-        if (ConstantInt *CI = dyn_cast<ConstantInt>(Inc->getOperand(1)))
-          if (CI->equalsInt(1))
-            return PN;
-  }
-  return 0;
-}
-
-/// getCanonicalInductionVariableIncrement - Return the LLVM value that holds
-/// the canonical induction variable value for the "next" iteration of the loop.
-/// This always succeeds if getCanonicalInductionVariable succeeds.
-///
-Instruction *Loop::getCanonicalInductionVariableIncrement() const {
-  if (PHINode *PN = getCanonicalInductionVariable()) {
-    bool P1InLoop = contains(PN->getIncomingBlock(1));
-    return cast<Instruction>(PN->getIncomingValue(P1InLoop));
-  }
-  return 0;
-}
-
-/// getTripCount - Return a loop-invariant LLVM value indicating the number of
-/// times the loop will be executed.  Note that this means that the backedge of
-/// the loop executes N-1 times.  If the trip-count cannot be determined, this
-/// returns null.
-///
-Value *Loop::getTripCount() const {
-  // Canonical loops will end with a 'cmp ne I, V', where I is the incremented
-  // canonical induction variable and V is the trip count of the loop.
-  Instruction *Inc = getCanonicalInductionVariableIncrement();
-  if (Inc == 0) return 0;
-  PHINode *IV = cast<PHINode>(Inc->getOperand(0));
-
-  BasicBlock *BackedgeBlock =
-    IV->getIncomingBlock(contains(IV->getIncomingBlock(1)));
-
-  if (BranchInst *BI = dyn_cast<BranchInst>(BackedgeBlock->getTerminator()))
-    if (BI->isConditional()) {
-      if (ICmpInst *ICI = dyn_cast<ICmpInst>(BI->getCondition())) {
-        if (ICI->getOperand(0) == Inc)
-          if (BI->getSuccessor(0) == getHeader()) {
-            if (ICI->getPredicate() == ICmpInst::ICMP_NE)
-              return ICI->getOperand(1);
-          } else if (ICI->getPredicate() == ICmpInst::ICMP_EQ) {
-            return ICI->getOperand(1);
-          }
-      }
-    }
-
-  return 0;
-}
-
-/// isLCSSAForm - Return true if the Loop is in LCSSA form
-bool Loop::isLCSSAForm() const { 
-  // Sort the blocks vector so that we can use binary search to do quick
-  // lookups.
-  SmallPtrSet<BasicBlock*, 16> LoopBBs(block_begin(), block_end());
-  
-  for (block_iterator BI = block_begin(), E = block_end(); BI != E; ++BI) {
-    BasicBlock *BB = *BI;
-    for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ++I)
-      for (Value::use_iterator UI = I->use_begin(), E = I->use_end(); UI != E;
-           ++UI) {
-        BasicBlock *UserBB = cast<Instruction>(*UI)->getParent();
-        if (PHINode *P = dyn_cast<PHINode>(*UI)) {
-          unsigned OperandNo = UI.getOperandNo();
-          UserBB = P->getIncomingBlock(OperandNo/2);
-        }
-        
-        // Check the current block, as a fast-path.  Most values are used in the
-        // same block they are defined in.
-        if (UserBB != BB && !LoopBBs.count(UserBB))
-          return false;
-      }
-  }
-  
-  return true;
-}
-
-//===-------------------------------------------------------------------===//
-// APIs for updating loop information after changing the CFG
-//
-
-/// addBasicBlockToLoop - This function is used by other analyses to update loop
-/// information.  NewBB is set to be a new member of the current loop.  Because
-/// of this, it is added as a member of all parent loops, and is added to the
-/// specified LoopInfo object as being in the current basic block.  It is not
-/// valid to replace the loop header with this method.
-///
-void Loop::addBasicBlockToLoop(BasicBlock *NewBB, LoopInfo &LI) {
-  assert((Blocks.empty() || LI[getHeader()] == this) &&
-         "Incorrect LI specified for this loop!");
-  assert(NewBB && "Cannot add a null basic block to the loop!");
-  assert(LI[NewBB] == 0 && "BasicBlock already in the loop!");
-
-  // Add the loop mapping to the LoopInfo object...
-  LI.BBMap[NewBB] = this;
-
-  // Add the basic block to this loop and all parent loops...
-  Loop *L = this;
-  while (L) {
-    L->Blocks.push_back(NewBB);
-    L = L->getParentLoop();
-  }
-}
-
-/// replaceChildLoopWith - This is used when splitting loops up.  It replaces
-/// the OldChild entry in our children list with NewChild, and updates the
-/// parent pointers of the two loops as appropriate.
-void Loop::replaceChildLoopWith(Loop *OldChild, Loop *NewChild) {
-  assert(OldChild->ParentLoop == this && "This loop is already broken!");
-  assert(NewChild->ParentLoop == 0 && "NewChild already has a parent!");
-  std::vector<Loop*>::iterator I = std::find(SubLoops.begin(), SubLoops.end(),
-                                             OldChild);
-  assert(I != SubLoops.end() && "OldChild not in loop!");
-  *I = NewChild;
-  OldChild->ParentLoop = 0;
-  NewChild->ParentLoop = this;
-}
-
-/// addChildLoop - Add the specified loop to be a child of this loop.
-///
-void Loop::addChildLoop(Loop *NewChild) {
-  assert(NewChild->ParentLoop == 0 && "NewChild already has a parent!");
-  NewChild->ParentLoop = this;
-  SubLoops.push_back(NewChild);
-}
-
-template<typename T>
-static void RemoveFromVector(std::vector<T*> &V, T *N) {
-  typename std::vector<T*>::iterator I = std::find(V.begin(), V.end(), N);
-  assert(I != V.end() && "N is not in this list!");
-  V.erase(I);
-}
-
-/// removeChildLoop - This removes the specified child from being a subloop of
-/// this loop.  The loop is not deleted, as it will presumably be inserted
-/// into another loop.
-Loop *Loop::removeChildLoop(iterator I) {
-  assert(I != SubLoops.end() && "Cannot remove end iterator!");
-  Loop *Child = *I;
-  assert(Child->ParentLoop == this && "Child is not a child of this loop!");
-  SubLoops.erase(SubLoops.begin()+(I-begin()));
-  Child->ParentLoop = 0;
-  return Child;
-}
-
-
-/// removeBlockFromLoop - This removes the specified basic block from the
-/// current loop, updating the Blocks and ExitBlocks lists as appropriate.  This
-/// does not update the mapping in the LoopInfo class.
-void Loop::removeBlockFromLoop(BasicBlock *BB) {
-  RemoveFromVector(Blocks, BB);
-}
-
 // Ensure this file gets linked when LoopInfo.h is used.
 DEFINING_FILE_FOR(LoopInfo)