Fix crash in debug output.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11659 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/RegAllocLinearScan.cpp b/lib/CodeGen/RegAllocLinearScan.cpp
index b24f6c8..25c37f6 100644
--- a/lib/CodeGen/RegAllocLinearScan.cpp
+++ b/lib/CodeGen/RegAllocLinearScan.cpp
@@ -735,7 +735,7 @@
                     DEBUG(std::cerr << "\t\t\t\tadded store for reg" << li->reg
                           << " to ss#" << slot << " after: \t\t"
                           << LiveIntervals::getBaseIndex(index) << " \t";
-                          prior(mi,2)->print(std::cerr, *tm_));
+                          mi->print(std::cerr, *tm_));
                 }
             }
         }