src/libcompiler_builtins/compiler-rt/lib/fuzzer/FuzzerRandom.h

   1 //===- FuzzerRandom.h - Internal header for the Fuzzer ----------*- C++ -* ===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 // fuzzer::Random
  10 //===----------------------------------------------------------------------===//
  11
  12 #ifndef LLVM_FUZZER_RANDOM_H
  13 #define LLVM_FUZZER_RANDOM_H
  14
  15 #include <random>
  16
  17 namespace fuzzer {
  18 class Random : public std::mt19937 {
  19  public:
  20   Random(unsigned int seed) : std::mt19937(seed) {}
  21   result_type operator()() { return this->std::mt19937::operator()(); }
  22   size_t Rand() { return this->operator()(); }
  23   size_t RandBool() { return Rand() % 2; }
  24   size_t operator()(size_t n) { return n ? Rand() % n : 0; }
  25   intptr_t operator()(intptr_t From, intptr_t To) {
  26     assert(From < To);
  27     intptr_t RangeSize = To - From + 1;
  28     return operator()(RangeSize) + From;
  29   }
  30 };
  31
  32 }  // namespace fuzzer
  33
  34 #endif  // LLVM_FUZZER_RANDOM_H