Import prebuilt clang toolchain for linux.
diff --git a/linux-x64/clang/include/llvm/Support/Valgrind.h b/linux-x64/clang/include/llvm/Support/Valgrind.h
new file mode 100644
index 0000000..084b901
--- /dev/null
+++ b/linux-x64/clang/include/llvm/Support/Valgrind.h
@@ -0,0 +1,32 @@
+//===- llvm/Support/Valgrind.h - Communication with Valgrind ----*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Methods for communicating with a valgrind instance this program is running
+// under. These are all no-ops unless LLVM was configured on a system with the
+// valgrind headers installed and valgrind is controlling this process.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_SUPPORT_VALGRIND_H
+#define LLVM_SUPPORT_VALGRIND_H
+
+#include <cstddef>
+
+namespace llvm {
+namespace sys {
+ // True if Valgrind is controlling this process.
+ bool RunningOnValgrind();
+
+ // Discard valgrind's translation of code in the range [Addr .. Addr + Len).
+ // Otherwise valgrind may continue to execute the old version of the code.
+ void ValgrindDiscardTranslations(const void *Addr, size_t Len);
+} // namespace sys
+} // end namespace llvm
+
+#endif // LLVM_SUPPORT_VALGRIND_H