mirror of
https://github.com/llvm/llvm-project.git
synced 2025-05-01 04:06:07 +00:00
59198d062f
The next step is to be able to benchmark several implementations at once and compare which one performs best on a particular machine. Differential Revision: https://reviews.llvm.org/D107265
124 lines
4.6 KiB
C++
124 lines
4.6 KiB
C++
//===-- Benchmark memory specific tools -----------------------------------===//
|
|
//
|
|
// 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
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#include "LibcMemoryBenchmark.h"
|
|
#include "llvm/ADT/SmallVector.h"
|
|
#include "llvm/ADT/Twine.h"
|
|
#include "llvm/Support/ErrorHandling.h"
|
|
#include "llvm/Support/MathExtras.h"
|
|
#include <algorithm>
|
|
|
|
namespace llvm {
|
|
namespace libc_benchmarks {
|
|
|
|
// Returns a distribution that samples the buffer to satisfy the required
|
|
// alignment.
|
|
// When alignment is set, the distribution is scaled down by `Factor` and scaled
|
|
// up again by the same amount during sampling.
|
|
static std::uniform_int_distribution<uint32_t>
|
|
getOffsetDistribution(size_t BufferSize, size_t MaxSizeValue,
|
|
MaybeAlign AccessAlignment) {
|
|
if (AccessAlignment && *AccessAlignment > AlignedBuffer::Alignment)
|
|
report_fatal_error(
|
|
"AccessAlignment must be less or equal to AlignedBuffer::Alignment");
|
|
if (!AccessAlignment)
|
|
return std::uniform_int_distribution<uint32_t>(0, 0); // Always 0.
|
|
// If we test up to Size bytes, the returned offset must stay under
|
|
// BuffersSize - Size.
|
|
int64_t MaxOffset = BufferSize;
|
|
MaxOffset -= MaxSizeValue;
|
|
MaxOffset -= 1;
|
|
if (MaxOffset < 0)
|
|
report_fatal_error(
|
|
"BufferSize too small to exercise specified Size configuration");
|
|
MaxOffset /= AccessAlignment->value();
|
|
return std::uniform_int_distribution<uint32_t>(0, MaxOffset);
|
|
}
|
|
|
|
OffsetDistribution::OffsetDistribution(size_t BufferSize, size_t MaxSizeValue,
|
|
MaybeAlign AccessAlignment)
|
|
: Distribution(
|
|
getOffsetDistribution(BufferSize, MaxSizeValue, AccessAlignment)),
|
|
Factor(AccessAlignment.valueOrOne().value()) {}
|
|
|
|
// Precomputes offset where to insert mismatches between the two buffers.
|
|
MismatchOffsetDistribution::MismatchOffsetDistribution(size_t BufferSize,
|
|
size_t MaxSizeValue,
|
|
size_t MismatchAt)
|
|
: MismatchAt(MismatchAt) {
|
|
if (MismatchAt <= 1)
|
|
return;
|
|
for (size_t I = MaxSizeValue + 1; I < BufferSize; I += MaxSizeValue)
|
|
MismatchIndices.push_back(I);
|
|
if (MismatchIndices.empty())
|
|
report_fatal_error("Unable to generate mismatch");
|
|
MismatchIndexSelector =
|
|
std::uniform_int_distribution<size_t>(0, MismatchIndices.size() - 1);
|
|
}
|
|
|
|
static size_t getL1DataCacheSize() {
|
|
const std::vector<CacheInfo> &CacheInfos = HostState::get().Caches;
|
|
const auto IsL1DataCache = [](const CacheInfo &CI) {
|
|
return CI.Type == "Data" && CI.Level == 1;
|
|
};
|
|
const auto CacheIt = find_if(CacheInfos, IsL1DataCache);
|
|
if (CacheIt != CacheInfos.end())
|
|
return CacheIt->Size;
|
|
report_fatal_error("Unable to read L1 Cache Data Size");
|
|
}
|
|
|
|
static size_t getAvailableBufferSize() {
|
|
static constexpr int64_t KiB = 1024;
|
|
static constexpr int64_t ParameterStorageBytes = 4 * KiB;
|
|
static constexpr int64_t L1LeftAsideBytes = 1 * KiB;
|
|
return getL1DataCacheSize() - L1LeftAsideBytes - ParameterStorageBytes;
|
|
}
|
|
|
|
ParameterBatch::ParameterBatch(size_t BufferCount)
|
|
: BufferSize(getAvailableBufferSize() / BufferCount),
|
|
BatchSize(BufferSize / sizeof(ParameterType)), Parameters(BatchSize) {
|
|
if (BufferSize <= 0 || BatchSize < 100)
|
|
report_fatal_error("Not enough L1 cache");
|
|
}
|
|
|
|
size_t ParameterBatch::getBatchBytes() const {
|
|
size_t BatchBytes = 0;
|
|
for (auto &P : Parameters)
|
|
BatchBytes += P.SizeBytes;
|
|
return BatchBytes;
|
|
}
|
|
|
|
void ParameterBatch::checkValid(const ParameterType &P) const {
|
|
if (P.OffsetBytes + P.SizeBytes >= BufferSize)
|
|
report_fatal_error(
|
|
llvm::Twine("Call would result in buffer overflow: Offset=")
|
|
.concat(llvm::Twine(P.OffsetBytes))
|
|
.concat(", Size=")
|
|
.concat(llvm::Twine(P.SizeBytes))
|
|
.concat(", BufferSize=")
|
|
.concat(llvm::Twine(BufferSize)));
|
|
}
|
|
|
|
CopyHarness::CopyHarness()
|
|
: ParameterBatch(2), SrcBuffer(ParameterBatch::BufferSize),
|
|
DstBuffer(ParameterBatch::BufferSize) {}
|
|
|
|
ComparisonHarness::ComparisonHarness()
|
|
: ParameterBatch(2), LhsBuffer(ParameterBatch::BufferSize),
|
|
RhsBuffer(ParameterBatch::BufferSize) {
|
|
// The memcmp buffers always compare equal.
|
|
memset(LhsBuffer.begin(), 0xF, BufferSize);
|
|
memset(RhsBuffer.begin(), 0xF, BufferSize);
|
|
}
|
|
|
|
SetHarness::SetHarness()
|
|
: ParameterBatch(1), DstBuffer(ParameterBatch::BufferSize) {}
|
|
|
|
} // namespace libc_benchmarks
|
|
} // namespace llvm
|