Eliminate data relocations by using NULL instead of global empty list.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29250 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/LiveIntervalAnalysis.cpp b/lib/CodeGen/LiveIntervalAnalysis.cpp
index fba0467..9e0d5d2 100644
--- a/lib/CodeGen/LiveIntervalAnalysis.cpp
+++ b/lib/CodeGen/LiveIntervalAnalysis.cpp
@@ -639,8 +639,10 @@
       DEBUG(std::cerr << getInstructionIndex(mi) << "\t" << *mi);
 
       // handle implicit defs
-      for (const unsigned* id = tid.ImplicitDefs; *id; ++id)
-        handleRegisterDef(mbb, mi, *id);
+      if (tid.ImplicitDefs) {
+        for (const unsigned* id = tid.ImplicitDefs; *id; ++id)
+          handleRegisterDef(mbb, mi, *id);
+      }
 
       // handle explicit defs
       for (int i = mi->getNumOperands() - 1; i >= 0; --i) {