Revert my last patch until I consult with Evan about it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@58591 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/PreAllocSplitting.cpp b/lib/CodeGen/PreAllocSplitting.cpp
index 4044b73..8f223b3 100644 (file)
--- a/lib/CodeGen/PreAllocSplitting.cpp
+++ b/lib/CodeGen/PreAllocSplitting.cpp
@@ -89,8 +89,6 @@ namespace {
         AU.addPreservedID(StrongPHIEliminationID);
       else
         AU.addPreservedID(PHIEliminationID);
-      AU.addRequired<MachineLoopInfo>();
-      AU.addPreserved<MachineLoopInfo>();
       MachineFunctionPass::getAnalysisUsage(AU);
     }
     
@@ -635,14 +633,6 @@ bool PreAllocSplitting::SplitRegLiveInterval(LiveInterval *LI) {
     assert(0 && "Val# is defined by a dead def?");
     abort();
   }
-  
-  // Pre-splitting a vreg that does not have a PHI kill across a barrier
-  // that is within a loop can potentially create a join that was not
-  // present before, which would make updating the live intervals very
-  // difficult.  Bailout instead.
-  MachineLoopInfo& MLI = getAnalysis<MachineLoopInfo>();
-  if (!ValNo->hasPHIKill && MLI.getLoopFor(BarrierMBB))
-    return false;
 
   // FIXME: For now, if definition is rematerializable, do not split.
   MachineInstr *DefMI = (ValNo->def != ~0U)