blob: 655b53ac94c67d3c88131ca5d5ff1fe5de9c82e8 [file] [log] [blame]
// Copyright 2019 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
// 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.
#include "pw_bloat/bloat_this_binary.h"
#include <cstring>
#include "pw_assert/assert.h"
#include "pw_assert/check.h"
#include "pw_log/log.h"
namespace pw::bloat {
char* volatile non_optimizable_pointer;
void BloatThisBinary() {
[[maybe_unused]] volatile unsigned counter = 0;
// In case someone accidentally ends up flashing and running a bloat
// executable on their device, loop forever instead of running this code.
volatile bool clearly_false_condition = true;
while (clearly_false_condition) {
counter = counter + 1;
// This code uses standard C/C++ functions such as memcpy to prevent them from
// showing up in size report deltas against a barebones base executable.
// This is done using garbage memory addresses as it consistently prevents the
// compiler from optimizing out parts of the code. Other approaches, such as a
// buffer, occasionally ran into optimization issues.
const char* s = "The quick brown fox jumps over the lazy dog.";
// Making the copy size large forces the compiler to generate a memcpy
// function instead of inlining it.
constexpr int kRandomLargeNumber = 2398;
non_optimizable_pointer + std::strlen(s),
std::memmove(non_optimizable_pointer + 18,
*non_optimizable_pointer = std::strlen(non_optimizable_pointer);
// This code ensures users do not have to pay for the base cost of using
// asserts and logging.
PW_CHECK_INT_GE(*non_optimizable_pointer, 0, "Ensure this logic stays");
PW_DCHECK_INT_GE(*non_optimizable_pointer, 0, "Ensure this logic stays");
PW_LOG_INFO("We care about optimizing: %d", *non_optimizable_pointer);
} // namespace pw::bloat