v8/src/v8conversions.h
2013-12-20 13:33:20 +00:00

114 lines
3.9 KiB
C++

// Copyright 2011 the V8 project authors. All rights reserved.
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * 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.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "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 THE COPYRIGHT
// OWNER 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.
#ifndef V8_V8CONVERSIONS_H_
#define V8_V8CONVERSIONS_H_
#include "conversions.h"
namespace v8 {
namespace internal {
static inline bool IsMinusZero(double value) {
static const DoubleRepresentation minus_zero(-0.0);
return DoubleRepresentation(value) == minus_zero;
}
// Integer32 is an integer that can be represented as a signed 32-bit
// integer. It has to be in the range [-2^31, 2^31 - 1].
// We also have to check for negative 0 as it is not an Integer32.
static inline bool IsInt32Double(double value) {
return !IsMinusZero(value) &&
value >= kMinInt &&
value <= kMaxInt &&
value == FastI2D(FastD2I(value));
}
// Convert from Number object to C integer.
inline int32_t NumberToInt32(Object* number) {
if (number->IsSmi()) return Smi::cast(number)->value();
return DoubleToInt32(number->Number());
}
inline uint32_t NumberToUint32(Object* number) {
if (number->IsSmi()) return Smi::cast(number)->value();
return DoubleToUint32(number->Number());
}
// Converts a string into a double value according to ECMA-262 9.3.1
double StringToDouble(UnicodeCache* unicode_cache,
String* str,
int flags,
double empty_string_val = 0);
// Converts a string into an integer.
double StringToInt(UnicodeCache* unicode_cache, String* str, int radix);
inline bool TryNumberToSize(Isolate* isolate,
Object* number, size_t* result) {
SealHandleScope shs(isolate);
if (number->IsSmi()) {
int value = Smi::cast(number)->value();
ASSERT(
static_cast<unsigned>(Smi::kMaxValue)
<= std::numeric_limits<size_t>::max());
if (value >= 0) {
*result = static_cast<size_t>(value);
return true;
}
return false;
} else {
ASSERT(number->IsHeapNumber());
double value = HeapNumber::cast(number)->value();
if (value >= 0 &&
value <= std::numeric_limits<size_t>::max()) {
*result = static_cast<size_t>(value);
return true;
} else {
return false;
}
}
}
// Converts a number into size_t.
inline size_t NumberToSize(Isolate* isolate,
Object* number) {
size_t result = 0;
bool is_valid = TryNumberToSize(isolate, number, &result);
CHECK(is_valid);
return result;
}
} } // namespace v8::internal
#endif // V8_V8CONVERSIONS_H_