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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* vim: set ts=8 sts=2 et sw=2 tw=80:
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef jit_ScalarTypeUtils_h
#define jit_ScalarTypeUtils_h
#include "mozilla/CheckedInt.h"
#include <stdint.h>
#include "js/ScalarType.h"
namespace js {
namespace jit {
// Compute |index * Scalar::byteSize(type) + offsetAdjustment|. If this doesn't
// overflow and is non-negative, return true and store the result in *offset.
// If the computation overflows or the result is negative, false is returned and
// *offset is left unchanged.
[[nodiscard]] inline bool ArrayOffsetFitsInInt32(int32_t index,
Scalar::Type type,
int32_t offsetAdjustment,
int32_t* offset) {
mozilla::CheckedInt<int32_t> val = index;
val *= Scalar::byteSize(type);
val += offsetAdjustment;
if (!val.isValid() || val.value() < 0) {
return false;
}
*offset = val.value();
return true;
}
} // namespace jit
} // namespace js
#endif /* jit_ScalarTypeUtils_h */
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