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/*
* Copyright (C) 2018 The Android Open Source Project
*
* 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
*
* http://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.
*/
#include <stdint.h>
#include <stdlib.h>
#include "TestUtils.h"
// The loop in this function is only guaranteed to not be optimized away by the compiler
// if optimizations are turned off. This is partially because the compiler doesn't have
// any idea about the function since it is retrieved using dlsym.
//
// In an effort to defend against the compiler:
// 1. The loop iteration variable is volatile.
// 2. A call to this function should be wrapped in TestUtils::DoNotOptimize().
extern "C" int BusyWait() {
for (size_t i = 0; i < 1000000;) {
unwindstack::DoNotOptimize(i++);
}
return 0;
}
// Do a loop that guarantees the terminating leaf frame will be in
// the this library and not a function from a different library.
extern "C" void WaitForever() {
bool run = true;
while (run) {
unwindstack::DoNotOptimize(run = true);
}
}
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