Don't transfer unused values to the new intervals formed by splitting.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117673 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SplitKit.cpp b/lib/CodeGen/SplitKit.cpp
index 84d3003..763cce8 100644
--- a/lib/CodeGen/SplitKit.cpp
+++ b/lib/CodeGen/SplitKit.cpp
@@ -913,6 +913,9 @@
   for (LiveInterval::const_vni_iterator I = parent.vni_begin(),
        E = parent.vni_end(); I != E; ++I) {
     const VNInfo *VNI = *I;
+    // Don't transfer unused values to the new intervals.
+    if (VNI->isUnused())
+      continue;
     // Original def is contained in the split intervals.
     if (intervalsLiveAt(VNI->def)) {
       // Did this value escape?