1//===- FuzzerExtraCounters.cpp - Extra coverage counters ------------------===// 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// Extra coverage counters defined by user code. 10//===----------------------------------------------------------------------===// 11 12#include "FuzzerDefs.h" 13 14#if LIBFUZZER_LINUX || LIBFUZZER_NETBSD || LIBFUZZER_FREEBSD || \ 15 LIBFUZZER_OPENBSD 16__attribute__((weak)) extern uint8_t __start___libfuzzer_extra_counters; 17__attribute__((weak)) extern uint8_t __stop___libfuzzer_extra_counters; 18 19namespace fuzzer { 20uint8_t *ExtraCountersBegin() { return &__start___libfuzzer_extra_counters; } 21uint8_t *ExtraCountersEnd() { return &__stop___libfuzzer_extra_counters; } 22ATTRIBUTE_NO_SANITIZE_ALL 23void ClearExtraCounters() { // hand-written memset, don't asan-ify. 24 uintptr_t *Beg = reinterpret_cast<uintptr_t*>(ExtraCountersBegin()); 25 uintptr_t *End = reinterpret_cast<uintptr_t*>(ExtraCountersEnd()); 26 for (; Beg < End; Beg++) { 27 *Beg = 0; 28 __asm__ __volatile__("" : : : "memory"); 29 } 30} 31 32} // namespace fuzzer 33 34#else 35// TODO: implement for other platforms. 36namespace fuzzer { 37uint8_t *ExtraCountersBegin() { return nullptr; } 38uint8_t *ExtraCountersEnd() { return nullptr; } 39void ClearExtraCounters() {} 40} // namespace fuzzer 41 42#endif 43