Merge "Update prebuilt Clang to r353983." into p9.0HEADp9.0-backupp9.0

1 files changed, 69 insertions, 0 deletions

diff --git a/clang-r353983/include/llvm/Support/RandomNumberGenerator.h b/clang-r353983/include/llvm/Support/RandomNumberGenerator.h
new file mode 100644
index 00000000..55d6876c
--- /dev/null
+++ b/clang-r353983/include/llvm/Support/RandomNumberGenerator.h
@@ -0,0 +1,69 @@
+//==- llvm/Support/RandomNumberGenerator.h - RNG for diversity ---*- 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
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines an abstraction for deterministic random number
+// generation (RNG).  Note that the current implementation is not
+// cryptographically secure as it uses the C++11 <random> facilities.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_SUPPORT_RANDOMNUMBERGENERATOR_H_
+#define LLVM_SUPPORT_RANDOMNUMBERGENERATOR_H_
+
+#include "llvm/Support/Compiler.h"
+#include "llvm/Support/DataTypes.h" // Needed for uint64_t on Windows.
+#include <random>
+#include <system_error>
+
+namespace llvm {
+class StringRef;
+
+/// A random number generator.
+///
+/// Instances of this class should not be shared across threads. The
+/// seed should be set by passing the -rng-seed=<uint64> option. Use
+/// Module::createRNG to create a new RNG instance for use with that
+/// module.
+class RandomNumberGenerator {
+
+  // 64-bit Mersenne Twister by Matsumoto and Nishimura, 2000
+  // http://en.cppreference.com/w/cpp/numeric/random/mersenne_twister_engine
+  // This RNG is deterministically portable across C++11
+  // implementations.
+  using generator_type = std::mt19937_64;
+
+public:
+  using result_type = generator_type::result_type;
+
+  /// Returns a random number in the range [0, Max).
+  result_type operator()();
+
+  static constexpr result_type min() { return generator_type::min(); }
+  static constexpr result_type max() { return generator_type::max(); }
+
+private:
+  /// Seeds and salts the underlying RNG engine.
+  ///
+  /// This constructor should not be used directly. Instead use
+  /// Module::createRNG to create a new RNG salted with the Module ID.
+  RandomNumberGenerator(StringRef Salt);
+
+  generator_type Generator;
+
+  // Noncopyable.
+  RandomNumberGenerator(const RandomNumberGenerator &other) = delete;
+  RandomNumberGenerator &operator=(const RandomNumberGenerator &other) = delete;
+
+  friend class Module;
+};
+
+// Get random vector of specified size
+std::error_code getRandomBytes(void *Buffer, size_t Size);
+}
+
+#endif