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1//===-- Generic utilities for GPU timing ----------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9#ifndef LLVM_LIBC_SRC_TIME_GPU_TIME_UTILS_H10#define LLVM_LIBC_SRC_TIME_GPU_TIME_UTILS_H11 12#include "hdr/time_macros.h"13#include "hdr/types/clock_t.h"14#include "src/__support/GPU/utils.h"15#include "src/__support/macros/config.h"16 17namespace LIBC_NAMESPACE_DECL {18 19#if defined(LIBC_TARGET_ARCH_IS_AMDGPU)20// AMDGPU does not have a single set frequency. Different architectures and21// cards can have different values. The actualy frequency needs to be read from22// the kernel driver and will be between 25 MHz and 100 MHz on most cards. All23// cards following the GFX9 ISAs use a 100 MHz clock so we will default to that.24constexpr uint64_t clock_freq = 100000000UL;25 26// We provide an externally visible symbol such that the runtime can set27// this to the correct value.28extern "C" {29[[gnu::visibility("protected")]]30extern gpu::Constant<uint64_t> __llvm_libc_clock_freq;31}32#define GPU_CLOCKS_PER_SEC static_cast<clock_t>(__llvm_libc_clock_freq)33 34#elif defined(LIBC_TARGET_ARCH_IS_NVPTX)35// NPVTX uses a single 1 GHz fixed frequency clock for all target architectures.36#define GPU_CLOCKS_PER_SEC static_cast<clock_t>(1000000000UL)37#else38#error "Unsupported target"39#endif40 41constexpr uint64_t TICKS_PER_SEC = 1000000000UL;42 43} // namespace LIBC_NAMESPACE_DECL44 45#endif // LLVM_LIBC_SRC_TIME_GPU_TIME_UTILS_H46