Avoid eraseing copies from a reserved register unless the definition can be

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

diff --git a/lib/CodeGen/RegAllocBasic.cpp b/lib/CodeGen/RegAllocBasic.cpp
index 8bb8556bc889ad777ce4f14d2241040fe8cff375..8019cf227bdc3db68e14e0382a76ca50e2b7ee69 100644 (file)
--- a/lib/CodeGen/RegAllocBasic.cpp
+++ b/lib/CodeGen/RegAllocBasic.cpp
@@ -20,7 +20,6 @@
 #include "RenderMachineFunction.h"
 #include "Spiller.h"
 #include "VirtRegMap.h"
-#include "RegisterCoalescer.h"
 #include "llvm/ADT/OwningPtr.h"
 #include "llvm/ADT/Statistic.h"
 #include "llvm/Analysis/AliasAnalysis.h"
@@ -160,7 +159,7 @@ void RABasic::getAnalysisUsage(AnalysisUsage &AU) const {
   AU.addPreserved<LiveDebugVariables>();
   if (StrongPHIElim)
     AU.addRequiredID(StrongPHIEliminationID);
-  AU.addRequiredTransitive<RegisterCoalescer>();
+  AU.addRequiredTransitiveID(RegisterCoalescerPassID);
   AU.addRequired<CalculateSpillWeights>();
   AU.addRequired<LiveStacks>();
   AU.addPreserved<LiveStacks>();
@@ -234,6 +233,7 @@ void RegAllocBase::init(VirtRegMap &vrm, LiveIntervals &lis) {
   MRI = &vrm.getRegInfo();
   VRM = &vrm;
   LIS = &lis;
+  MRI->freezeReservedRegs(vrm.getMachineFunction());
   RegClassInfo.runOnMachineFunction(vrm.getMachineFunction());
 
   const unsigned NumRegs = TRI->getNumRegs();
@@ -499,8 +499,9 @@ unsigned RABasic::selectOrSplit(LiveInterval &VirtReg,
       // Found an available register.
       return PhysReg;
     }
+    Queries[interfReg].collectInterferingVRegs(1);
     LiveInterval *interferingVirtReg =
-      Queries[interfReg].firstInterference().liveUnionPos().value();
+      Queries[interfReg].interferingVRegs().front();
 
     // The current VirtReg must either be spillable, or one of its interferences
     // must have less spill weight.