// 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 // Tests whether scaling the Entropic scheduling weight based on input execution // time is effective or not. Inputs of size 10 will take at least 100 // microseconds more than any input of size 1-9. The input of size 2 in the // corpus should be favored by the exec-time-scaled Entropic scheduling policy // than the input of size 10 in the corpus, eventually finding the crashing // input {0xab, 0xcd} with less executions. #include #include #include static volatile int Sink; static volatile int *Nil = nullptr; extern "C" int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) { if (Size > 10) return 0; // To make the test quicker. if (Size != 2) { // execute a lot slower than the crashing input below. size_t ExecTimeUSec = 100; std::this_thread::sleep_for(std::chrono::microseconds(ExecTimeUSec)); if (Size > 0 && Data[0] == 0xaa && Size > 1 && Data[1] == 0xbb && Size > 2 && Data[2] == 0xcc && Size > 3 && Data[3] == 0xdd && Size > 4 && Data[4] == 0xee && Size > 5 && Data[5] == 0xff) Sink += 7; } if (Size == 2 && Data[0] == 0xab && Data[1] == 0xcd) *Nil = 42; // crash. return 0; }