Index: src/diy_fp.h |
=================================================================== |
--- src/diy_fp.h (revision 4180) |
+++ src/diy_fp.h (working copy) |
@@ -1,117 +0,0 @@ |
-// 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_DIY_FP_H_ |
-#define V8_DIY_FP_H_ |
- |
-namespace v8 { |
-namespace internal { |
- |
-// This "Do It Yourself Floating Point" class implements a floating-point number |
-// with a uint64 significand and an int exponent. Normalized DiyFp numbers will |
-// have the most significant bit of the significand set. |
-// Multiplication and Subtraction do not normalize their results. |
-// DiyFp are not designed to contain special doubles (NaN and Infinity). |
-class DiyFp { |
- public: |
- static const int kSignificandSize = 64; |
- |
- DiyFp() : f_(0), e_(0) {} |
- DiyFp(uint64_t f, int e) : f_(f), e_(e) {} |
- |
- // this = this - other. |
- // The exponents of both numbers must be the same and the significand of this |
- // must be bigger than the significand of other. |
- // The result will not be normalized. |
- void Subtract(const DiyFp& other) { |
- ASSERT(e_ == other.e_); |
- ASSERT(f_ >= other.f_); |
- f_ -= other.f_; |
- } |
- |
- // Returns a - b. |
- // The exponents of both numbers must be the same and this must be bigger |
- // than other. The result will not be normalized. |
- static DiyFp Minus(const DiyFp& a, const DiyFp& b) { |
- DiyFp result = a; |
- result.Subtract(b); |
- return result; |
- } |
- |
- |
- // this = this * other. |
- void Multiply(const DiyFp& other); |
- |
- // returns a * b; |
- static DiyFp Times(const DiyFp& a, const DiyFp& b) { |
- DiyFp result = a; |
- result.Multiply(b); |
- return result; |
- } |
- |
- void Normalize() { |
- ASSERT(f_ != 0); |
- uint64_t f = f_; |
- int e = e_; |
- |
- // This method is mainly called for normalizing boundaries. In general |
- // boundaries need to be shifted by 10 bits. We thus optimize for this case. |
- const uint64_t k10MSBits = V8_2PART_UINT64_C(0xFFC00000, 00000000); |
- while ((f & k10MSBits) == 0) { |
- f <<= 10; |
- e -= 10; |
- } |
- while ((f & kUint64MSB) == 0) { |
- f <<= 1; |
- e--; |
- } |
- f_ = f; |
- e_ = e; |
- } |
- |
- static DiyFp Normalize(const DiyFp& a) { |
- DiyFp result = a; |
- result.Normalize(); |
- return result; |
- } |
- |
- uint64_t f() const { return f_; } |
- int e() const { return e_; } |
- |
- void set_f(uint64_t new_value) { f_ = new_value; } |
- void set_e(int new_value) { e_ = new_value; } |
- |
- private: |
- static const uint64_t kUint64MSB = V8_2PART_UINT64_C(0x80000000, 00000000); |
- |
- uint64_t f_; |
- int e_; |
-}; |
- |
-} } // namespace v8::internal |
- |
-#endif // V8_DIY_FP_H_ |