forked from OSchip/llvm-project
65 lines
2.6 KiB
C++
65 lines
2.6 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/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);
|
|
}
|
|
|
|
} // namespace libc_benchmarks
|
|
} // namespace llvm
|