diff --git a/llvm/lib/Target/X86/X86ISelPattern.cpp b/llvm/lib/Target/X86/X86ISelPattern.cpp
index f574a63..35796e9 100644
--- a/llvm/lib/Target/X86/X86ISelPattern.cpp
+++ b/llvm/lib/Target/X86/X86ISelPattern.cpp
@@ -27,6 +27,7 @@
 #include "llvm/Support/MathExtras.h"
 #include "llvm/ADT/Statistic.h"
 #include <set>
+#include <algorithm>
 using namespace llvm;
 
 //===----------------------------------------------------------------------===//