Simplify hasNUsesOfValue and hasAnyUsesOfValue even more. This

[oota-llvm.git] / lib / CodeGen / BranchFolding.cpp

diff --git a/lib/CodeGen/BranchFolding.cpp b/lib/CodeGen/BranchFolding.cpp
index 1807f98cb139f3844efe4581219ee05e5a1c78af..f6b3d9cada5066d602eb1ffcb4ae93055ef09d6b 100644 (file)
--- a/lib/CodeGen/BranchFolding.cpp
+++ b/lib/CodeGen/BranchFolding.cpp
@@ -38,13 +38,13 @@ STATISTIC(NumBranchOpts, "Number of branches optimized");
 STATISTIC(NumTailMerge , "Number of block tails merged");
 static cl::opt<cl::boolOrDefault> FlagEnableTailMerge("enable-tail-merge", 
                               cl::init(cl::BOU_UNSET), cl::Hidden);
-namespace {
-  // Throttle for huge numbers of predecessors (compile speed problems)
-  static cl::opt<unsigned>
-  TailMergeThreshold("tail-merge-threshold", 
-            cl::desc("Max number of predecessors to consider tail merging"),
-            cl::init(100), cl::Hidden);
+// Throttle for huge numbers of predecessors (compile speed problems)
+static cl::opt<unsigned>
+TailMergeThreshold("tail-merge-threshold", 
+          cl::desc("Max number of predecessors to consider tail merging"),
+          cl::init(100), cl::Hidden);
 
+namespace {
   struct VISIBILITY_HIDDEN BranchFolder : public MachineFunctionPass {
     static char ID;
     explicit BranchFolder(bool defaultEnableTailMerge) : 
@@ -114,12 +114,12 @@ void BranchFolder::RemoveDeadBlock(MachineBasicBlock *MBB) {
   while (!MBB->succ_empty())
     MBB->removeSuccessor(MBB->succ_end()-1);
   
-  // If there is DWARF info to active, check to see if there are any LABEL
+  // If there is DWARF info to active, check to see if there are any DBG_LABEL
   // records in the basic block.  If so, unregister them from MachineModuleInfo.
   if (MMI && !MBB->empty()) {
     for (MachineBasicBlock::iterator I = MBB->begin(), E = MBB->end();
          I != E; ++I) {
-      if ((unsigned)I->getOpcode() == TargetInstrInfo::LABEL) {
+      if ((unsigned)I->getOpcode() == TargetInstrInfo::DBG_LABEL) {
         // The label ID # is always operand #0, an immediate.
         MMI->InvalidateLabel(I->getOperand(0).getImm());
       }
@@ -127,7 +127,7 @@ void BranchFolder::RemoveDeadBlock(MachineBasicBlock *MBB) {
   }
   
   // Remove the block.
-  MF->getBasicBlockList().erase(MBB);
+  MF->erase(MBB);
 }
 
 /// OptimizeImpDefsBlock - If a basic block is just a bunch of implicit_def
@@ -375,17 +375,15 @@ void BranchFolder::ReplaceTailWithBranchTo(MachineBasicBlock::iterator OldInst,
 /// iterator.  This returns the new MBB.
 MachineBasicBlock *BranchFolder::SplitMBBAt(MachineBasicBlock &CurMBB,
                                             MachineBasicBlock::iterator BBI1) {
+  MachineFunction &MF = *CurMBB.getParent();
+
   // Create the fall-through block.
   MachineFunction::iterator MBBI = &CurMBB;
-  MachineBasicBlock *NewMBB = new MachineBasicBlock(CurMBB.getBasicBlock());
-  CurMBB.getParent()->getBasicBlockList().insert(++MBBI, NewMBB);
+  MachineBasicBlock *NewMBB =MF.CreateMachineBasicBlock(CurMBB.getBasicBlock());
+  CurMBB.getParent()->insert(++MBBI, NewMBB);
 
   // Move all the successors of this block to the specified block.
-  while (!CurMBB.succ_empty()) {
-    MachineBasicBlock *S = *(CurMBB.succ_end()-1);
-    NewMBB->addSuccessor(S);
-    CurMBB.removeSuccessor(S);
-  }
+  NewMBB->transferSuccessors(&CurMBB);
  
   // Add an edge from CurMBB to NewMBB for the fall-through.
   CurMBB.addSuccessor(NewMBB);
@@ -529,18 +527,20 @@ unsigned BranchFolder::ComputeSameTails(unsigned CurHash,
 void BranchFolder::RemoveBlocksWithHash(unsigned CurHash, 
                                         MachineBasicBlock* SuccBB,
                                         MachineBasicBlock* PredBB) {
-  for (MPIterator CurMPIter = prior(MergePotentials.end()),
-                  B = MergePotentials.begin(); 
+  MPIterator CurMPIter, B;
+  for (CurMPIter = prior(MergePotentials.end()), B = MergePotentials.begin(); 
        CurMPIter->first==CurHash;
        --CurMPIter) {
     // Put the unconditional branch back, if we need one.
     MachineBasicBlock *CurMBB = CurMPIter->second;
     if (SuccBB && CurMBB != PredBB)
       FixTail(CurMBB, SuccBB, TII);
-    MergePotentials.erase(CurMPIter);
-    if (CurMPIter==B) 
+    if (CurMPIter==B)
       break;
   }
+  if (CurMPIter->first!=CurHash)
+    CurMPIter++;
+  MergePotentials.erase(CurMPIter, MergePotentials.end());
 }
 
 /// CreateCommonTailOnlyBlock - None of the blocks to be tail-merged consist
@@ -699,8 +699,7 @@ bool BranchFolder::TailMergeBlocks(MachineFunction &MF) {
   // transformations.)
 
   for (MachineFunction::iterator I = MF.begin(), E = MF.end(); I != E; ++I) {
-    if (!I->succ_empty() && I->pred_size() >= 2 && 
-         I->pred_size() < TailMergeThreshold) {
+    if (I->pred_size() >= 2 && I->pred_size() < TailMergeThreshold) {
       MachineBasicBlock *IBB = I;
       MachineBasicBlock *PredBB = prior(I);
       MergePotentials.clear();