/// 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).
- uint_fast64_t operator()();
+ 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.
/// Module::createRNG to create a new RNG salted with the Module ID.
RandomNumberGenerator(StringRef Salt);
- // 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.
- std::mt19937_64 Generator;
+ generator_type Generator;
// Noncopyable.
RandomNumberGenerator(const RandomNumberGenerator &other) = delete;
#include "llvm/IR/GlobalVariable.h"
#include "llvm/IR/Module.h"
+#include "llvm/Support/RandomNumberGenerator.h"
#include "gtest/gtest.h"
+#include <random>
+
using namespace llvm;
namespace {
}
}
+TEST(ModuleTest, randomNumberGenerator) {
+ LLVMContext Context;
+ static char ID;
+ struct DummyPass : ModulePass {
+ DummyPass() : ModulePass(ID) {}
+ bool runOnModule(Module &) { return true; }
+ } DP;
+
+ Module M("R", Context);
+
+ std::uniform_int_distribution<int> dist;
+ constexpr std::size_t NBCheck = 10;
+
+ std::array<int, NBCheck> RandomStreams[2];
+ for (auto &RandomStream : RandomStreams) {
+ std::unique_ptr<RandomNumberGenerator> RNG{M.createRNG(&DP)};
+ std::generate(RandomStream.begin(), RandomStream.end(),
+ [&]() { return dist(*RNG); });
+ }
+
+ EXPECT_TRUE(std::equal(RandomStreams[0].begin(), RandomStreams[0].end(),
+ RandomStreams[1].begin()));
+}
+
} // end namespace