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// Copyright 2023 The Pigweed Authors
//
// Licensed under the Apache License, Version 2.0 (the "License"); you may not
// use this file except in compliance with the License. You may obtain a copy of
// the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
// License for the specific language governing permissions and limitations under
// the License.
// This size report uses pw::string::Format and std::snprintf to write a single
// printf-style string to a buffer. The number of bytes written is returned.
//
// This compares the overhead of using pw::string::Format to directly calling
// std::snprintf and determining the number of bytes written. It demonstrates
// that the code for using pw::string::Format is much simpler.
#include "pw_allocator/split_free_list_allocator.h"
#include "pw_bloat/bloat_this_binary.h"
#ifdef SIZE_REPORT_METRIC_PROXY
#include "pw_allocator/allocator_metric_proxy.h"
#endif // SIZE_REPORT_METRIC_PROXY
namespace {
pw::allocator::SplitFreeListAllocator allocator;
#ifdef SIZE_REPORT_METRIC_PROXY
pw::allocator::AllocatorMetricProxy proxy(0);
#endif // SIZE_REPORT_METRIC_PROXY
constexpr void* kFakeMemoryRegionStart = &allocator;
constexpr size_t kFakeMemoryRegionSize = 4096;
constexpr size_t kSplitFreeListThreshold = 128;
} // namespace
int main() {
pw::bloat::BloatThisBinary();
allocator.Init(
pw::ByteSpan(reinterpret_cast<std::byte*>(kFakeMemoryRegionStart),
kFakeMemoryRegionSize),
kSplitFreeListThreshold);
struct Foo {
char name[16];
};
struct Bar : public Foo {
int number;
};
// Small allocation.
Foo* foo =
static_cast<Foo*>(allocator.Allocate(pw::allocator::Layout::Of<Foo>()));
if (foo == nullptr) {
return 1;
}
foo->name[0] = '\0';
// Reallocate.
Bar* bar = static_cast<Bar*>(
allocator.Reallocate(foo, pw::allocator::Layout::Of<Foo>(), sizeof(Bar)));
if (bar == nullptr) {
return 1;
}
bar->number = 4;
// Large allocation.
struct Baz {
std::byte data[kSplitFreeListThreshold * 2];
};
Baz* baz =
static_cast<Baz*>(allocator.Allocate(pw::allocator::Layout::Of<Baz>()));
if (baz == nullptr) {
return 1;
}
baz->data[kSplitFreeListThreshold] = std::byte(0xf1);
// Deallocate.
allocator.Deallocate(bar, pw::allocator::Layout::Of<Bar>());
allocator.Deallocate(baz, pw::allocator::Layout::Of<Baz>());
#ifdef SIZE_REPORT_UNIQUE_PTR
struct Point {
int x;
int y;
Point(int xx, int yy) : x(xx), y(yy) {}
};
{
std::optional<pw::allocator::UniquePtr<Point>> maybe_point =
allocator.MakeUnique<Point>(3, 4);
if (!maybe_point.has_value()) {
return 1;
}
pw::allocator::UniquePtr<Point> point = *maybe_point;
point->x = point->y * 2;
}
#endif // SIZE_REPORT_UNIQUE_PTR
#ifdef SIZE_REPORT_METRIC_PROXY
proxy.Initialize(allocator);
Foo* foo2 =
static_cast<Foo*>(proxy.Allocate(pw::allocator::Layout::Of<Foo>()));
if (foo2 == nullptr) {
return 1;
}
foo2->name[1] = 'a';
proxy.Deallocate(foo2, pw::allocator::Layout::Of<Foo>());
#endif // SIZE_REPORT_METRIC_PROXY
return 0;
}
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