Source/JavaScriptCore/jit/ExecutableAllocationFuzz.cpp

/*
 * Copyright (C) 2015 Apple Inc. All rights reserved.
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 *
 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
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 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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#include "config.h"
#include "ExecutableAllocationFuzz.h"

#include "TestRunnerUtils.h"
#include <wtf/Atomics.h>
#include <wtf/DataLog.h>

namespace JSC {

static Atomic<unsigned> s_numberOfExecutableAllocationFuzzChecks;
unsigned numberOfExecutableAllocationFuzzChecks()
{
    return s_numberOfExecutableAllocationFuzzChecks.load();
}

ExecutableAllocationFuzzResult doExecutableAllocationFuzzing()
{
    ASSERT(Options::useExecutableAllocationFuzz());
    
    unsigned oldValue;
    unsigned newValue;
    do {
        oldValue = s_numberOfExecutableAllocationFuzzChecks.load();
        newValue = oldValue + 1;
    } while (!s_numberOfExecutableAllocationFuzzChecks.compareExchangeWeak(oldValue, newValue));
    
    if (newValue == Options::fireExecutableAllocationFuzzAt()) {
        if (Options::verboseExecutableAllocationFuzz()) {
            dataLog("Will pretend to fail executable allocation.\n");
            WTFReportBacktrace();
        }
        return PretendToFailExecutableAllocation;
    }
    
    if (Options::fireExecutableAllocationFuzzAtOrAfter()
        && newValue >= Options::fireExecutableAllocationFuzzAtOrAfter()) {
        if (Options::verboseExecutableAllocationFuzz()) {
            dataLog("Will pretend to fail executable allocation.\n");
            WTFReportBacktrace();
        }
        return PretendToFailExecutableAllocation;
    }
    
    return AllowNormalExecutableAllocation;
}

} // namespace JSC