//===-- X86Counter.h --------------------------------------------*- 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 // //===----------------------------------------------------------------------===// /// /// \file /// Perf counter that reads the LBRs for measuring the benchmarked block's /// throughput. /// /// More info at: https://lwn.net/Articles/680985 //===----------------------------------------------------------------------===// #ifndef LLVM_TOOLS_LLVM_EXEGESIS_LIB_X86_X86COUNTER_H #define LLVM_TOOLS_LLVM_EXEGESIS_LIB_X86_X86COUNTER_H #include "../PerfHelper.h" #include "llvm/Support/Error.h" // FIXME: Use appropriate wrappers for poll.h and mman.h // to support Windows and remove this linux-only guard. #if defined(__linux__) && defined(HAVE_LIBPFM) && \ defined(LIBPFM_HAS_FIELD_CYCLES) namespace llvm { namespace exegesis { class X86LbrPerfEvent : public pfm::PerfEvent { public: X86LbrPerfEvent(unsigned SamplingPeriod); }; class X86LbrCounter : public pfm::CounterGroup { public: static Error checkLbrSupport(); explicit X86LbrCounter(pfm::PerfEvent &&Event); virtual ~X86LbrCounter(); void start() override; Expected<SmallVector<int64_t, 4>> readOrError(StringRef FunctionBytes) const override; private: Expected<SmallVector<int64_t, 4>> doReadCounter(const void *From, const void *To) const; void *MMappedBuffer = nullptr; }; } // namespace exegesis } // namespace llvm #endif // defined(__linux__) && defined(HAVE_LIBPFM) && // defined(LIBPFM_HAS_FIELD_CYCLES) #endif // LLVM_TOOLS_LLVM_EXEGESIS_LIB_X86_X86COUNTER_H