diff --git a/libc/utils/testutils/StreamWrapper.cpp b/libc/utils/testutils/StreamWrapper.cpp
@@ -8,6 +8,7 @@
 
 #include "StreamWrapper.h"
 #include <cassert>
+#include <fstream>
 #include <iostream>
 #include <memory>
 #include <string>
@@ -21,6 +22,7 @@ template <typename T> StreamWrapper &StreamWrapper::operator<<(T t) {
   assert(OS);
   std::ostream &Stream = *reinterpret_cast<std::ostream *>(OS);
   Stream << t;
+  Stream.flush();
   return *this;
 }
 
@@ -43,6 +45,15 @@ template StreamWrapper &
     StreamWrapper::operator<<<unsigned long long>(unsigned long long t);
 template StreamWrapper &StreamWrapper::operator<<<bool>(bool t);
 template StreamWrapper &StreamWrapper::operator<<<std::string>(std::string t);
+template StreamWrapper &StreamWrapper::operator<<<float>(float t);
+template StreamWrapper &StreamWrapper::operator<<<double>(double t);
+
+OutputFileStream::OutputFileStream(const char *FN)
+    : StreamWrapper(new std::ofstream(FN)) {}
+
+OutputFileStream::~OutputFileStream() {
+  delete reinterpret_cast<std::ofstream *>(OS);
+}
 
 } // namespace testutils
 } // namespace __llvm_libc
diff --git a/libc/utils/testutils/StreamWrapper.h b/libc/utils/testutils/StreamWrapper.h
@@ -16,6 +16,7 @@ namespace testutils {
 // standard headers so we must provide streams through indirection to not
 // expose the system libc headers.
 class StreamWrapper {
+protected:
   void *OS;
 
 public:
@@ -26,6 +27,12 @@ class StreamWrapper {
 
 StreamWrapper outs();
 
+class OutputFileStream : public StreamWrapper {
+public:
+  explicit OutputFileStream(const char *FN);
+  ~OutputFileStream();
+};
+
 } // namespace testutils
 } // namespace __llvm_libc
 

diff --git a/libc/utils/testutils/Timer.cpp b/libc/utils/testutils/Timer.cpp
@@ -0,0 +1,42 @@
+//===-- Timer.cpp --------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "Timer.h"
+
+#include <chrono>
+#include <fstream>
+
+namespace __llvm_libc {
+namespace testing {
+
+struct TimerImplementation {
+  std::chrono::high_resolution_clock::time_point Start;
+  std::chrono::high_resolution_clock::time_point End;
+};
+
+Timer::Timer() : Impl(new TimerImplementation) {}
+
+Timer::~Timer() { delete reinterpret_cast<TimerImplementation *>(Impl); }
+
+void Timer::start() {
+  auto T = reinterpret_cast<TimerImplementation *>(Impl);
+  T->Start = std::chrono::high_resolution_clock::now();
+}
+
+void Timer::stop() {
+  auto T = reinterpret_cast<TimerImplementation *>(Impl);
+  T->End = std::chrono::high_resolution_clock::now();
+}
+
+uint64_t Timer::nanoseconds() const {
+  auto T = reinterpret_cast<TimerImplementation *>(Impl);
+  return std::chrono::nanoseconds(T->End - T->Start).count();
+}
+
+} // namespace testing
+} // namespace __llvm_libc
diff --git a/libc/utils/testutils/Timer.h b/libc/utils/testutils/Timer.h
@@ -0,0 +1,33 @@
+//===-- Timer.h -------------------------------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_UTILS_TESTUTILS_TIMER_H
+#define LLVM_LIBC_UTILS_TESTUTILS_TIMER_H
+
+#include <stdint.h>
+
+namespace __llvm_libc {
+namespace testing {
+
+class Timer {
+  void *Impl;
+
+public:
+  Timer();
+  ~Timer();
+
+  void start();
+  void stop();
+
+  uint64_t nanoseconds() const;
+};
+
+} // namespace testing
+} // namespace __llvm_libc
+
+#endif // LLVM_LIBC_UTILS_TESTUTILS_TIMER_H