Add a missing #include, patch courtesy of Baptiste Lepilleur.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23302 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index bffc176..ddbe45a 100644
--- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -40,6 +40,7 @@
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/MathExtras.h"
 #include "llvm/Target/TargetLowering.h"
+#include <algorithm>
 #include <cmath>
 using namespace llvm;