Use uint16_t to store register overlaps to reduce static data.

llvm-svn: 152001
diff --git a/llvm/lib/CodeGen/RegAllocBase.cpp b/llvm/lib/CodeGen/RegAllocBase.cpp
index e088023..85119c9 100644
--- a/llvm/lib/CodeGen/RegAllocBase.cpp
+++ b/llvm/lib/CodeGen/RegAllocBase.cpp
@@ -236,7 +236,7 @@
 // physical register. Return the interfering register.
 unsigned RegAllocBase::checkPhysRegInterference(LiveInterval &VirtReg,
                                                 unsigned PhysReg) {
-  for (const unsigned *AliasI = TRI->getOverlaps(PhysReg); *AliasI; ++AliasI)
+  for (const uint16_t *AliasI = TRI->getOverlaps(PhysReg); *AliasI; ++AliasI)
     if (query(VirtReg, *AliasI).checkInterference())
       return *AliasI;
   return 0;