Down-scale slot index distance to save bits.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187438 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/RegAllocGreedy.cpp b/lib/CodeGen/RegAllocGreedy.cpp
index 87b11a5..f9e363b 100644
--- a/lib/CodeGen/RegAllocGreedy.cpp
+++ b/lib/CodeGen/RegAllocGreedy.cpp
@@ -419,7 +419,7 @@
       // Allocate original local ranges in linear instruction order. Since they
       // are singly defined, this produces optimal coloring in the absence of
       // global interference and other constraints.
-      Prio = LI->beginIndex().distance(Indexes->getLastIndex());
+      Prio = LI->beginIndex().getInstrDistance(Indexes->getLastIndex());
     }
     else {
       // Allocate global and split ranges in long->short order. Long ranges that