Update V8 to r5804 as required by WebKit r72274
Change-Id: I287670630b22383dbce46e4a6fad4ec9eb37d8b8
diff --git a/src/bignum.h b/src/bignum.h
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+++ b/src/bignum.h
@@ -0,0 +1,140 @@
+// Copyright 2010 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_BIGNUM_H_
+#define V8_BIGNUM_H_
+
+namespace v8 {
+namespace internal {
+
+class Bignum {
+ public:
+ // 3584 = 128 * 28. We can represent 2^3584 > 10^1000 accurately.
+ // This bignum can encode much bigger numbers, since it contains an
+ // exponent.
+ static const int kMaxSignificantBits = 3584;
+
+ Bignum();
+ void AssignUInt16(uint16_t value);
+ void AssignUInt64(uint64_t value);
+ void AssignBignum(const Bignum& other);
+
+ void AssignDecimalString(Vector<const char> value);
+ void AssignHexString(Vector<const char> value);
+
+ void AssignPowerUInt16(uint16_t base, int exponent);
+
+ void AddUInt16(uint16_t operand);
+ void AddUInt64(uint64_t operand);
+ void AddBignum(const Bignum& other);
+ // Precondition: this >= other.
+ void SubtractBignum(const Bignum& other);
+
+ void Square();
+ void ShiftLeft(int shift_amount);
+ void MultiplyByUInt32(uint32_t factor);
+ void MultiplyByUInt64(uint64_t factor);
+ void MultiplyByPowerOfTen(int exponent);
+ void Times10() { return MultiplyByUInt32(10); }
+ // Pseudocode:
+ // int result = this / other;
+ // this = this % other;
+ // In the worst case this function is in O(this/other).
+ uint16_t DivideModuloIntBignum(const Bignum& other);
+
+ bool ToHexString(char* buffer, int buffer_size) const;
+
+ static int Compare(const Bignum& a, const Bignum& b);
+ static bool Equal(const Bignum& a, const Bignum& b) {
+ return Compare(a, b) == 0;
+ }
+ static bool LessEqual(const Bignum& a, const Bignum& b) {
+ return Compare(a, b) <= 0;
+ }
+ static bool Less(const Bignum& a, const Bignum& b) {
+ return Compare(a, b) < 0;
+ }
+ // Returns Compare(a + b, c);
+ static int PlusCompare(const Bignum& a, const Bignum& b, const Bignum& c);
+ // Returns a + b == c
+ static bool PlusEqual(const Bignum& a, const Bignum& b, const Bignum& c) {
+ return PlusCompare(a, b, c) == 0;
+ }
+ // Returns a + b <= c
+ static bool PlusLessEqual(const Bignum& a, const Bignum& b, const Bignum& c) {
+ return PlusCompare(a, b, c) <= 0;
+ }
+ // Returns a + b < c
+ static bool PlusLess(const Bignum& a, const Bignum& b, const Bignum& c) {
+ return PlusCompare(a, b, c) < 0;
+ }
+ private:
+ typedef uint32_t Chunk;
+ typedef uint64_t DoubleChunk;
+
+ static const int kChunkSize = sizeof(Chunk) * 8;
+ static const int kDoubleChunkSize = sizeof(DoubleChunk) * 8;
+ // With bigit size of 28 we loose some bits, but a double still fits easily
+ // into two chunks, and more importantly we can use the Comba multiplication.
+ static const int kBigitSize = 28;
+ static const Chunk kBigitMask = (1 << kBigitSize) - 1;
+ // Every instance allocates kBigitLength chunks on the stack. Bignums cannot
+ // grow. There are no checks if the stack-allocated space is sufficient.
+ static const int kBigitCapacity = kMaxSignificantBits / kBigitSize;
+
+ void EnsureCapacity(int size) {
+ if (size > kBigitCapacity) {
+ UNREACHABLE();
+ }
+ }
+ void Align(const Bignum& other);
+ void Clamp();
+ bool IsClamped() const;
+ void Zero();
+ // Requires this to have enough capacity (no tests done).
+ // Updates used_digits_ if necessary.
+ // by must be < kBigitSize.
+ void BigitsShiftLeft(int shift_amount);
+ // BigitLength includes the "hidden" digits encoded in the exponent.
+ int BigitLength() const { return used_digits_ + exponent_; }
+ Chunk BigitAt(int index) const;
+ void SubtractTimes(const Bignum& other, int factor);
+
+ Chunk bigits_buffer_[kBigitCapacity];
+ // A vector backed by bigits_buffer_. This way accesses to the array are
+ // checked for out-of-bounds errors.
+ Vector<Chunk> bigits_;
+ int used_digits_;
+ // The Bignum's value equals value(bigits_) * 2^(exponent_ * kBigitSize).
+ int exponent_;
+
+ DISALLOW_COPY_AND_ASSIGN(Bignum);
+};
+
+} } // namespace v8::internal
+
+#endif // V8_BIGNUM_H_