blob: 69a478902945b2deafd0efeda2f49b42be076b9e [file] [log] [blame]
/*
* Copyright (C) 2016 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "config.h"
#include "ArrayConventions.h"
#include "JSCInlines.h"
namespace JSC {
#if USE(JSVALUE64)
void clearArrayMemset(WriteBarrier<Unknown>* base, unsigned count)
{
#if CPU(X86_64) && COMPILER(GCC_OR_CLANG)
uint64_t zero = 0;
asm volatile (
"rep stosq\n\t"
: "+D"(base), "+c"(count)
: "a"(zero)
: "memory"
);
#else // not CPU(X86_64)
memset(base, 0, count * sizeof(WriteBarrier<Unknown>));
#endif // generic CPU
}
void clearArrayMemset(double* base, unsigned count)
{
#if CPU(X86_64) && COMPILER(GCC_OR_CLANG)
uint64_t pnan = bitwise_cast<uint64_t>(PNaN);
asm volatile (
"rep stosq\n\t"
: "+D"(base), "+c"(count)
: "a"(pnan)
: "memory"
);
#else // not CPU(X86_64)
// Oh no, we can't actually do any better than this!
for (unsigned i = count; i--;)
base[i] = PNaN;
#endif // generic CPU
}
#endif // USE(JSVALUE64)
} // namespace JSC