Improved tracking of value number kills. VN kills are now represented

as an (index,bool) pair. The bool flag records whether the kill is a
PHI kill or not. This code will be used to enable splitting of live
intervals containing PHI-kills.

A slight change to live interval weights introduced an extra spill
into lsr-code-insertion (outside the critical sections). The test 
condition has been updated to reflect this.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75097 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/CodeGen/LiveIntervalAnalysis.h

@@ -88,6 +88,8 @@ namespace llvm {
     typedef DenseMap<unsigned, LiveInterval*> Reg2IntervalMap;
     Reg2IntervalMap r2iMap_;
 
+    DenseMap<MachineBasicBlock*, unsigned> terminatorGaps;
+
     BitVector allocatableRegs_;
 
     std::vector<MachineInstr*> ClonedMIs;