Record whether the weights on out-edges from a MBB are normalized.

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

diff --git a/lib/CodeGen/LiveIntervalAnalysis.cpp b/lib/CodeGen/LiveIntervalAnalysis.cpp
index adca4cc738e1e7801a3ed8f48fff67964ed55c74..9738dac65ad8e6fa351f4809d92930ffb5ae9caa 100644 (file)
--- a/lib/CodeGen/LiveIntervalAnalysis.cpp
+++ b/lib/CodeGen/LiveIntervalAnalysis.cpp
@@ -223,11 +223,11 @@ void LiveIntervals::computeRegMasks() {
     RMB.first = RegMaskSlots.size();
     for (MachineBasicBlock::iterator MI = MBB->begin(), ME = MBB->end();
          MI != ME; ++MI)
-      for (MIOperands MO(MI); MO.isValid(); ++MO) {
-        if (!MO->isRegMask())
+      for (const MachineOperand &MO : MI->operands()) {
+        if (!MO.isRegMask())
           continue;
           RegMaskSlots.push_back(Indexes->getInstructionIndex(MI).getRegSlot());
-          RegMaskBits.push_back(MO->getRegMask());
+          RegMaskBits.push_back(MO.getRegMask());
       }
     // Compute the number of register mask instructions in this block.
     RMB.second = RegMaskSlots.size() - RMB.first;
@@ -396,9 +396,6 @@ static void extendSegmentsToUses(LiveRange &LR, const SlotIndexes &Indexes,
   }
 }
 
-/// shrinkToUses - After removing some uses of a register, shrink its live
-/// range to just the remaining uses. This method does not compute reaching
-/// defs for new uses, and it doesn't remove dead defs.
 bool LiveIntervals::shrinkToUses(LiveInterval *li,
                                  SmallVectorImpl<MachineInstr*> *dead) {
   DEBUG(dbgs() << "Shrink: " << *li << '\n');
@@ -406,9 +403,14 @@ bool LiveIntervals::shrinkToUses(LiveInterval *li,
          && "Can only shrink virtual registers");
 
   // Shrink subregister live ranges.
+  bool NeedsCleanup = false;
   for (LiveInterval::SubRange &S : li->subranges()) {
     shrinkToUses(S, li->reg);
+    if (S.empty())
+      NeedsCleanup = true;
   }
+  if (NeedsCleanup)
+    li->removeEmptySubRanges();
 
   // Find all the values used, including PHI kills.
   ShrinkToUsesWorkList WorkList;
@@ -927,23 +929,23 @@ public:
   void updateAllRanges(MachineInstr *MI) {
     DEBUG(dbgs() << "handleMove " << OldIdx << " -> " << NewIdx << ": " << *MI);
     bool hasRegMask = false;
-    for (MIOperands MO(MI); MO.isValid(); ++MO) {
-      if (MO->isRegMask())
+    for (MachineOperand &MO : MI->operands()) {
+      if (MO.isRegMask())
         hasRegMask = true;
-      if (!MO->isReg())
+      if (!MO.isReg())
         continue;
       // Aggressively clear all kill flags.
       // They are reinserted by VirtRegRewriter.
-      if (MO->isUse())
-        MO->setIsKill(false);
+      if (MO.isUse())
+        MO.setIsKill(false);
 
-      unsigned Reg = MO->getReg();
+      unsigned Reg = MO.getReg();
       if (!Reg)
         continue;
       if (TargetRegisterInfo::isVirtualRegister(Reg)) {
         LiveInterval &LI = LIS.getInterval(Reg);
         if (LI.hasSubRanges()) {
-          unsigned SubReg = MO->getSubReg();
+          unsigned SubReg = MO.getSubReg();
           unsigned LaneMask = TRI.getSubRegIndexLaneMask(SubReg);
           for (LiveInterval::SubRange &S : LI.subranges()) {
             if ((S.LaneMask & LaneMask) == 0)