Import prebuilt clang toolchain for linux.
diff --git a/linux-x64/clang/include/llvm/CodeGen/ScheduleDAGMutation.h b/linux-x64/clang/include/llvm/CodeGen/ScheduleDAGMutation.h
new file mode 100644
index 0000000..5c23642
--- /dev/null
+++ b/linux-x64/clang/include/llvm/CodeGen/ScheduleDAGMutation.h
@@ -0,0 +1,34 @@
+//===- ScheduleDAGMutation.h - MachineInstr Scheduling ----------*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the ScheduleDAGMutation class, which represents
+// a target-specific mutation of the dependency graph for scheduling.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CODEGEN_SCHEDULEDAGMUTATION_H
+#define LLVM_CODEGEN_SCHEDULEDAGMUTATION_H
+
+namespace llvm {
+
+class ScheduleDAGInstrs;
+
+/// Mutate the DAG as a postpass after normal DAG building.
+class ScheduleDAGMutation {
+ virtual void anchor();
+
+public:
+ virtual ~ScheduleDAGMutation() = default;
+
+ virtual void apply(ScheduleDAGInstrs *DAG) = 0;
+};
+
+} // end namespace llvm
+
+#endif // LLVM_CODEGEN_SCHEDULEDAGMUTATION_H