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///////////////////////////////////////////////////////////////////////////
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//
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// Copyright (c) 2002, Industrial Light & Magic, a division of Lucas
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// Digital Ltd. LLC
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//
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// All rights reserved.
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//
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// Redistribution and use in source and binary forms, with or without
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// modification, are permitted provided that the following conditions are
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// met:
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// * Redistributions of source code must retain the above copyright
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// notice, this list of conditions and the following disclaimer.
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// * Redistributions in binary form must reproduce the above
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// copyright notice, this list of conditions and the following disclaimer
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// in the documentation and/or other materials provided with the
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// distribution.
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// * Neither the name of Industrial Light & Magic nor the names of
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// its contributors may be used to endorse or promote products derived
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// from this software without specific prior written permission.
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//
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// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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//
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///////////////////////////////////////////////////////////////////////////
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// Primary authors:
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// Florian Kainz <kainz@ilm.com>
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// Rod Bogart <rgb@ilm.com>
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//---------------------------------------------------------------------------
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//
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// half -- a 16-bit floating point number class:
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//
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// Type half can represent positive and negative numbers whose
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// magnitude is between roughly 6.1e-5 and 6.5e+4 with a relative
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// error of 9.8e-4; numbers smaller than 6.1e-5 can be represented
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// with an absolute error of 6.0e-8. All integers from -2048 to
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// +2048 can be represented exactly.
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//
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// Type half behaves (almost) like the built-in C++ floating point
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// types. In arithmetic expressions, half, float and double can be
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// mixed freely. Here are a few examples:
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//
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// half a (3.5);
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// float b (a + sqrt (a));
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// a += b;
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// b += a;
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// b = a + 7;
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//
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// Conversions from half to float are lossless; all half numbers
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// are exactly representable as floats.
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//
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// Conversions from float to half may not preserve a float's value
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// exactly. If a float is not representable as a half, then the
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// float value is rounded to the nearest representable half. If a
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// float value is exactly in the middle between the two closest
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// representable half values, then the float value is rounded to
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// the closest half whose least significant bit is zero.
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//
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// Overflows during float-to-half conversions cause arithmetic
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// exceptions. An overflow occurs when the float value to be
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// converted is too large to be represented as a half, or if the
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// float value is an infinity or a NAN.
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//
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// The implementation of type half makes the following assumptions
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// about the implementation of the built-in C++ types:
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//
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// float is an IEEE 754 single-precision number
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// sizeof (float) == 4
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// sizeof (unsigned int) == sizeof (float)
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// alignof (unsigned int) == alignof (float)
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// sizeof (unsigned short) == 2
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//
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//---------------------------------------------------------------------------
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#ifndef _HALF_H_
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#define _HALF_H_
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#include "halfExport.h" // for definition of HALF_EXPORT
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#include <iostream>
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class half
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{
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public:
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//-------------
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// Constructors
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//-------------
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half (); // no initialization
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half (float f);
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//--------------------
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// Conversion to float
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//--------------------
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operator float () const;
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//------------
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// Unary minus
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//------------
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half operator - () const;
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//-----------
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// Assignment
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//-----------
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half & operator = (half h);
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half & operator = (float f);
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half & operator += (half h);
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half & operator += (float f);
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half & operator -= (half h);
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half & operator -= (float f);
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half & operator *= (half h);
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half & operator *= (float f);
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half & operator /= (half h);
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half & operator /= (float f);
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//---------------------------------------------------------
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// Round to n-bit precision (n should be between 0 and 10).
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// After rounding, the significand's 10-n least significant
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// bits will be zero.
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//---------------------------------------------------------
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half round (unsigned int n) const;
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//--------------------------------------------------------------------
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// Classification:
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//
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// h.isFinite() returns true if h is a normalized number,
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// a denormalized number or zero
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//
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// h.isNormalized() returns true if h is a normalized number
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//
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// h.isDenormalized() returns true if h is a denormalized number
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//
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// h.isZero() returns true if h is zero
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//
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// h.isNan() returns true if h is a NAN
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//
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// h.isInfinity() returns true if h is a positive
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// or a negative infinity
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//
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// h.isNegative() returns true if the sign bit of h
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// is set (negative)
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//--------------------------------------------------------------------
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bool isFinite () const;
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bool isNormalized () const;
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bool isDenormalized () const;
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bool isZero () const;
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bool isNan () const;
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bool isInfinity () const;
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bool isNegative () const;
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//--------------------------------------------
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// Special values
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//
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// posInf() returns +infinity
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//
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// negInf() returns -infinity
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//
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// qNan() returns a NAN with the bit
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// pattern 0111111111111111
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//
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// sNan() returns a NAN with the bit
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// pattern 0111110111111111
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//--------------------------------------------
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static half posInf ();
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static half negInf ();
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static half qNan ();
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static half sNan ();
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//--------------------------------------
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// Access to the internal representation
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//--------------------------------------
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HALF_EXPORT unsigned short bits () const;
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HALF_EXPORT void setBits (unsigned short bits);
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public:
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union uif
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{
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unsigned int i;
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float f;
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};
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private:
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HALF_EXPORT static short convert (int i);
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HALF_EXPORT static float overflow ();
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|
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unsigned short _h;
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|
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HALF_EXPORT static const uif _toFloat[1 << 16];
|
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HALF_EXPORT static const unsigned short _eLut[1 << 9];
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};
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|
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//-----------
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// Stream I/O
|
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//-----------
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|
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HALF_EXPORT std::ostream & operator << (std::ostream &os, half h);
|
|
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HALF_EXPORT std::istream & operator >> (std::istream &is, half &h);
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|
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//----------
|
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// Debugging
|
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//----------
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|
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HALF_EXPORT void printBits (std::ostream &os, half h);
|
|
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HALF_EXPORT void printBits (std::ostream &os, float f);
|
|
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HALF_EXPORT void printBits (char c[19], half h);
|
|
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HALF_EXPORT void printBits (char c[35], float f);
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|
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//-------------------------------------------------------------------------
|
|
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// Limits
|
|
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//
|
|
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8dc392 |
// Visual C++ will complain if HALF_MIN, HALF_NRM_MIN etc. are not float
|
|
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// constants, but at least one other compiler (gcc 2.96) produces incorrect
|
|
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// results if they are.
|
|
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//-------------------------------------------------------------------------
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|
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|
|
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#if (defined _WIN32 || defined _WIN64) && defined _MSC_VER
|
|
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|
|
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#define HALF_MIN 5.96046448e-08f // Smallest positive half
|
|
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|
|
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#define HALF_NRM_MIN 6.10351562e-05f // Smallest positive normalized half
|
|
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|
|
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#define HALF_MAX 65504.0f // Largest positive half
|
|
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|
|
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8dc392 |
#define HALF_EPSILON 0.00097656f // Smallest positive e for which
|
|
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// half (1.0 + e) != half (1.0)
|
|
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#else
|
|
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|
|
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#define HALF_MIN 5.96046448e-08 // Smallest positive half
|
|
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|
|
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8dc392 |
#define HALF_NRM_MIN 6.10351562e-05 // Smallest positive normalized half
|
|
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8dc392 |
|
|
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8dc392 |
#define HALF_MAX 65504.0 // Largest positive half
|
|
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8dc392 |
|
|
Packit |
8dc392 |
#define HALF_EPSILON 0.00097656 // Smallest positive e for which
|
|
Packit |
8dc392 |
// half (1.0 + e) != half (1.0)
|
|
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8dc392 |
#endif
|
|
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|
|
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|
|
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8dc392 |
#define HALF_MANT_DIG 11 // Number of digits in mantissa
|
|
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8dc392 |
// (significand + hidden leading 1)
|
|
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|
|
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#define HALF_DIG 2 // Number of base 10 digits that
|
|
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8dc392 |
// can be represented without change
|
|
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8dc392 |
|
|
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8dc392 |
#define HALF_RADIX 2 // Base of the exponent
|
|
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8dc392 |
|
|
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8dc392 |
#define HALF_MIN_EXP -13 // Minimum negative integer such that
|
|
Packit |
8dc392 |
// HALF_RADIX raised to the power of
|
|
Packit |
8dc392 |
// one less than that integer is a
|
|
Packit |
8dc392 |
// normalized half
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
#define HALF_MAX_EXP 16 // Maximum positive integer such that
|
|
Packit |
8dc392 |
// HALF_RADIX raised to the power of
|
|
Packit |
8dc392 |
// one less than that integer is a
|
|
Packit |
8dc392 |
// normalized half
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
#define HALF_MIN_10_EXP -4 // Minimum positive integer such
|
|
Packit |
8dc392 |
// that 10 raised to that power is
|
|
Packit |
8dc392 |
// a normalized half
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
#define HALF_MAX_10_EXP 4 // Maximum positive integer such
|
|
Packit |
8dc392 |
// that 10 raised to that power is
|
|
Packit |
8dc392 |
// a normalized half
|
|
Packit |
8dc392 |
|
|
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8dc392 |
|
|
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8dc392 |
//---------------------------------------------------------------------------
|
|
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8dc392 |
//
|
|
Packit |
8dc392 |
// Implementation --
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// Representation of a float:
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// We assume that a float, f, is an IEEE 754 single-precision
|
|
Packit |
8dc392 |
// floating point number, whose bits are arranged as follows:
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// 31 (msb)
|
|
Packit |
8dc392 |
// |
|
|
Packit |
8dc392 |
// | 30 23
|
|
Packit |
8dc392 |
// | | |
|
|
Packit |
8dc392 |
// | | | 22 0 (lsb)
|
|
Packit |
8dc392 |
// | | | | |
|
|
Packit |
8dc392 |
// X XXXXXXXX XXXXXXXXXXXXXXXXXXXXXXX
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// s e m
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// S is the sign-bit, e is the exponent and m is the significand.
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// If e is between 1 and 254, f is a normalized number:
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// s e-127
|
|
Packit |
8dc392 |
// f = (-1) * 2 * 1.m
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// If e is 0, and m is not zero, f is a denormalized number:
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// s -126
|
|
Packit |
8dc392 |
// f = (-1) * 2 * 0.m
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// If e and m are both zero, f is zero:
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// f = 0.0
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// If e is 255, f is an "infinity" or "not a number" (NAN),
|
|
Packit |
8dc392 |
// depending on whether m is zero or not.
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// Examples:
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// 0 00000000 00000000000000000000000 = 0.0
|
|
Packit |
8dc392 |
// 0 01111110 00000000000000000000000 = 0.5
|
|
Packit |
8dc392 |
// 0 01111111 00000000000000000000000 = 1.0
|
|
Packit |
8dc392 |
// 0 10000000 00000000000000000000000 = 2.0
|
|
Packit |
8dc392 |
// 0 10000000 10000000000000000000000 = 3.0
|
|
Packit |
8dc392 |
// 1 10000101 11110000010000000000000 = -124.0625
|
|
Packit |
8dc392 |
// 0 11111111 00000000000000000000000 = +infinity
|
|
Packit |
8dc392 |
// 1 11111111 00000000000000000000000 = -infinity
|
|
Packit |
8dc392 |
// 0 11111111 10000000000000000000000 = NAN
|
|
Packit |
8dc392 |
// 1 11111111 11111111111111111111111 = NAN
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// Representation of a half:
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// Here is the bit-layout for a half number, h:
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// 15 (msb)
|
|
Packit |
8dc392 |
// |
|
|
Packit |
8dc392 |
// | 14 10
|
|
Packit |
8dc392 |
// | | |
|
|
Packit |
8dc392 |
// | | | 9 0 (lsb)
|
|
Packit |
8dc392 |
// | | | | |
|
|
Packit |
8dc392 |
// X XXXXX XXXXXXXXXX
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// s e m
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// S is the sign-bit, e is the exponent and m is the significand.
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// If e is between 1 and 30, h is a normalized number:
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// s e-15
|
|
Packit |
8dc392 |
// h = (-1) * 2 * 1.m
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// If e is 0, and m is not zero, h is a denormalized number:
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// S -14
|
|
Packit |
8dc392 |
// h = (-1) * 2 * 0.m
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// If e and m are both zero, h is zero:
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// h = 0.0
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// If e is 31, h is an "infinity" or "not a number" (NAN),
|
|
Packit |
8dc392 |
// depending on whether m is zero or not.
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// Examples:
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// 0 00000 0000000000 = 0.0
|
|
Packit |
8dc392 |
// 0 01110 0000000000 = 0.5
|
|
Packit |
8dc392 |
// 0 01111 0000000000 = 1.0
|
|
Packit |
8dc392 |
// 0 10000 0000000000 = 2.0
|
|
Packit |
8dc392 |
// 0 10000 1000000000 = 3.0
|
|
Packit |
8dc392 |
// 1 10101 1111000001 = -124.0625
|
|
Packit |
8dc392 |
// 0 11111 0000000000 = +infinity
|
|
Packit |
8dc392 |
// 1 11111 0000000000 = -infinity
|
|
Packit |
8dc392 |
// 0 11111 1000000000 = NAN
|
|
Packit |
8dc392 |
// 1 11111 1111111111 = NAN
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// Conversion:
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// Converting from a float to a half requires some non-trivial bit
|
|
Packit |
8dc392 |
// manipulations. In some cases, this makes conversion relatively
|
|
Packit |
8dc392 |
// slow, but the most common case is accelerated via table lookups.
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// Converting back from a half to a float is easier because we don't
|
|
Packit |
8dc392 |
// have to do any rounding. In addition, there are only 65536
|
|
Packit |
8dc392 |
// different half numbers; we can convert each of those numbers once
|
|
Packit |
8dc392 |
// and store the results in a table. Later, all conversions can be
|
|
Packit |
8dc392 |
// done using only simple table lookups.
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
//---------------------------------------------------------------------------
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
//--------------------
|
|
Packit |
8dc392 |
// Simple constructors
|
|
Packit |
8dc392 |
//--------------------
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
inline
|
|
Packit |
8dc392 |
half::half ()
|
|
Packit |
8dc392 |
{
|
|
Packit |
8dc392 |
// no initialization
|
|
Packit |
8dc392 |
}
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
//----------------------------
|
|
Packit |
8dc392 |
// Half-from-float constructor
|
|
Packit |
8dc392 |
//----------------------------
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
inline
|
|
Packit |
8dc392 |
half::half (float f)
|
|
Packit |
8dc392 |
{
|
|
Packit |
8dc392 |
uif x;
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
x.f = f;
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
if (f == 0)
|
|
Packit |
8dc392 |
{
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// Common special case - zero.
|
|
Packit |
8dc392 |
// Preserve the zero's sign bit.
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
_h = (x.i >> 16);
|
|
Packit |
8dc392 |
}
|
|
Packit |
8dc392 |
else
|
|
Packit |
8dc392 |
{
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// We extract the combined sign and exponent, e, from our
|
|
Packit |
8dc392 |
// floating-point number, f. Then we convert e to the sign
|
|
Packit |
8dc392 |
// and exponent of the half number via a table lookup.
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// For the most common case, where a normalized half is produced,
|
|
Packit |
8dc392 |
// the table lookup returns a non-zero value; in this case, all
|
|
Packit |
8dc392 |
// we have to do is round f's significand to 10 bits and combine
|
|
Packit |
8dc392 |
// the result with e.
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// For all other cases (overflow, zeroes, denormalized numbers
|
|
Packit |
8dc392 |
// resulting from underflow, infinities and NANs), the table
|
|
Packit |
8dc392 |
// lookup returns zero, and we call a longer, non-inline function
|
|
Packit |
8dc392 |
// to do the float-to-half conversion.
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
register int e = (x.i >> 23) & 0x000001ff;
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
e = _eLut[e];
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
if (e)
|
|
Packit |
8dc392 |
{
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// Simple case - round the significand, m, to 10
|
|
Packit |
8dc392 |
// bits and combine it with the sign and exponent.
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
register int m = x.i & 0x007fffff;
|
|
Packit |
8dc392 |
_h = e + ((m + 0x00000fff + ((m >> 13) & 1)) >> 13);
|
|
Packit |
8dc392 |
}
|
|
Packit |
8dc392 |
else
|
|
Packit |
8dc392 |
{
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// Difficult case - call a function.
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
_h = convert (x.i);
|
|
Packit |
8dc392 |
}
|
|
Packit |
8dc392 |
}
|
|
Packit |
8dc392 |
}
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
//------------------------------------------
|
|
Packit |
8dc392 |
// Half-to-float conversion via table lookup
|
|
Packit |
8dc392 |
//------------------------------------------
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
inline
|
|
Packit |
8dc392 |
half::operator float () const
|
|
Packit |
8dc392 |
{
|
|
Packit |
8dc392 |
return _toFloat[_h].f;
|
|
Packit |
8dc392 |
}
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
//-------------------------
|
|
Packit |
8dc392 |
// Round to n-bit precision
|
|
Packit |
8dc392 |
//-------------------------
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
inline half
|
|
Packit |
8dc392 |
half::round (unsigned int n) const
|
|
Packit |
8dc392 |
{
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// Parameter check.
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
if (n >= 10)
|
|
Packit |
8dc392 |
return *this;
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// Disassemble h into the sign, s,
|
|
Packit |
8dc392 |
// and the combined exponent and significand, e.
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
unsigned short s = _h & 0x8000;
|
|
Packit |
8dc392 |
unsigned short e = _h & 0x7fff;
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// Round the exponent and significand to the nearest value
|
|
Packit |
8dc392 |
// where ones occur only in the (10-n) most significant bits.
|
|
Packit |
8dc392 |
// Note that the exponent adjusts automatically if rounding
|
|
Packit |
8dc392 |
// up causes the significand to overflow.
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
e >>= 9 - n;
|
|
Packit |
8dc392 |
e += e & 1;
|
|
Packit |
8dc392 |
e <<= 9 - n;
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// Check for exponent overflow.
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
if (e >= 0x7c00)
|
|
Packit |
8dc392 |
{
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// Overflow occurred -- truncate instead of rounding.
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
e = _h;
|
|
Packit |
8dc392 |
e >>= 10 - n;
|
|
Packit |
8dc392 |
e <<= 10 - n;
|
|
Packit |
8dc392 |
}
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
// Put the original sign bit back.
|
|
Packit |
8dc392 |
//
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
half h;
|
|
Packit |
8dc392 |
h._h = s | e;
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
return h;
|
|
Packit |
8dc392 |
}
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
//-----------------------
|
|
Packit |
8dc392 |
// Other inline functions
|
|
Packit |
8dc392 |
//-----------------------
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
inline half
|
|
Packit |
8dc392 |
half::operator - () const
|
|
Packit |
8dc392 |
{
|
|
Packit |
8dc392 |
half h;
|
|
Packit |
8dc392 |
h._h = _h ^ 0x8000;
|
|
Packit |
8dc392 |
return h;
|
|
Packit |
8dc392 |
}
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
inline half &
|
|
Packit |
8dc392 |
half::operator = (half h)
|
|
Packit |
8dc392 |
{
|
|
Packit |
8dc392 |
_h = h._h;
|
|
Packit |
8dc392 |
return *this;
|
|
Packit |
8dc392 |
}
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
inline half &
|
|
Packit |
8dc392 |
half::operator = (float f)
|
|
Packit |
8dc392 |
{
|
|
Packit |
8dc392 |
*this = half (f);
|
|
Packit |
8dc392 |
return *this;
|
|
Packit |
8dc392 |
}
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
inline half &
|
|
Packit |
8dc392 |
half::operator += (half h)
|
|
Packit |
8dc392 |
{
|
|
Packit |
8dc392 |
*this = half (float (*this) + float (h));
|
|
Packit |
8dc392 |
return *this;
|
|
Packit |
8dc392 |
}
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
inline half &
|
|
Packit |
8dc392 |
half::operator += (float f)
|
|
Packit |
8dc392 |
{
|
|
Packit |
8dc392 |
*this = half (float (*this) + f);
|
|
Packit |
8dc392 |
return *this;
|
|
Packit |
8dc392 |
}
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
inline half &
|
|
Packit |
8dc392 |
half::operator -= (half h)
|
|
Packit |
8dc392 |
{
|
|
Packit |
8dc392 |
*this = half (float (*this) - float (h));
|
|
Packit |
8dc392 |
return *this;
|
|
Packit |
8dc392 |
}
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
inline half &
|
|
Packit |
8dc392 |
half::operator -= (float f)
|
|
Packit |
8dc392 |
{
|
|
Packit |
8dc392 |
*this = half (float (*this) - f);
|
|
Packit |
8dc392 |
return *this;
|
|
Packit |
8dc392 |
}
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
inline half &
|
|
Packit |
8dc392 |
half::operator *= (half h)
|
|
Packit |
8dc392 |
{
|
|
Packit |
8dc392 |
*this = half (float (*this) * float (h));
|
|
Packit |
8dc392 |
return *this;
|
|
Packit |
8dc392 |
}
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
inline half &
|
|
Packit |
8dc392 |
half::operator *= (float f)
|
|
Packit |
8dc392 |
{
|
|
Packit |
8dc392 |
*this = half (float (*this) * f);
|
|
Packit |
8dc392 |
return *this;
|
|
Packit |
8dc392 |
}
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
inline half &
|
|
Packit |
8dc392 |
half::operator /= (half h)
|
|
Packit |
8dc392 |
{
|
|
Packit |
8dc392 |
*this = half (float (*this) / float (h));
|
|
Packit |
8dc392 |
return *this;
|
|
Packit |
8dc392 |
}
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
inline half &
|
|
Packit |
8dc392 |
half::operator /= (float f)
|
|
Packit |
8dc392 |
{
|
|
Packit |
8dc392 |
*this = half (float (*this) / f);
|
|
Packit |
8dc392 |
return *this;
|
|
Packit |
8dc392 |
}
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
inline bool
|
|
Packit |
8dc392 |
half::isFinite () const
|
|
Packit |
8dc392 |
{
|
|
Packit |
8dc392 |
unsigned short e = (_h >> 10) & 0x001f;
|
|
Packit |
8dc392 |
return e < 31;
|
|
Packit |
8dc392 |
}
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
inline bool
|
|
Packit |
8dc392 |
half::isNormalized () const
|
|
Packit |
8dc392 |
{
|
|
Packit |
8dc392 |
unsigned short e = (_h >> 10) & 0x001f;
|
|
Packit |
8dc392 |
return e > 0 && e < 31;
|
|
Packit |
8dc392 |
}
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
inline bool
|
|
Packit |
8dc392 |
half::isDenormalized () const
|
|
Packit |
8dc392 |
{
|
|
Packit |
8dc392 |
unsigned short e = (_h >> 10) & 0x001f;
|
|
Packit |
8dc392 |
unsigned short m = _h & 0x3ff;
|
|
Packit |
8dc392 |
return e == 0 && m != 0;
|
|
Packit |
8dc392 |
}
|
|
Packit |
8dc392 |
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Packit |
8dc392 |
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Packit |
8dc392 |
inline bool
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Packit |
8dc392 |
half::isZero () const
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Packit |
8dc392 |
{
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Packit |
8dc392 |
return (_h & 0x7fff) == 0;
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Packit |
8dc392 |
}
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Packit |
8dc392 |
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Packit |
8dc392 |
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Packit |
8dc392 |
inline bool
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Packit |
8dc392 |
half::isNan () const
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Packit |
8dc392 |
{
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Packit |
8dc392 |
unsigned short e = (_h >> 10) & 0x001f;
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Packit |
8dc392 |
unsigned short m = _h & 0x3ff;
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Packit |
8dc392 |
return e == 31 && m != 0;
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Packit |
8dc392 |
}
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Packit |
8dc392 |
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Packit |
8dc392 |
|
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Packit |
8dc392 |
inline bool
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Packit |
8dc392 |
half::isInfinity () const
|
|
Packit |
8dc392 |
{
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|
Packit |
8dc392 |
unsigned short e = (_h >> 10) & 0x001f;
|
|
Packit |
8dc392 |
unsigned short m = _h & 0x3ff;
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|
Packit |
8dc392 |
return e == 31 && m == 0;
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|
Packit |
8dc392 |
}
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|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
inline bool
|
|
Packit |
8dc392 |
half::isNegative () const
|
|
Packit |
8dc392 |
{
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|
Packit |
8dc392 |
return (_h & 0x8000) != 0;
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|
Packit |
8dc392 |
}
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|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
inline half
|
|
Packit |
8dc392 |
half::posInf ()
|
|
Packit |
8dc392 |
{
|
|
Packit |
8dc392 |
half h;
|
|
Packit |
8dc392 |
h._h = 0x7c00;
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|
Packit |
8dc392 |
return h;
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|
Packit |
8dc392 |
}
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|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
inline half
|
|
Packit |
8dc392 |
half::negInf ()
|
|
Packit |
8dc392 |
{
|
|
Packit |
8dc392 |
half h;
|
|
Packit |
8dc392 |
h._h = 0xfc00;
|
|
Packit |
8dc392 |
return h;
|
|
Packit |
8dc392 |
}
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
inline half
|
|
Packit |
8dc392 |
half::qNan ()
|
|
Packit |
8dc392 |
{
|
|
Packit |
8dc392 |
half h;
|
|
Packit |
8dc392 |
h._h = 0x7fff;
|
|
Packit |
8dc392 |
return h;
|
|
Packit |
8dc392 |
}
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
inline half
|
|
Packit |
8dc392 |
half::sNan ()
|
|
Packit |
8dc392 |
{
|
|
Packit |
8dc392 |
half h;
|
|
Packit |
8dc392 |
h._h = 0x7dff;
|
|
Packit |
8dc392 |
return h;
|
|
Packit |
8dc392 |
}
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
inline unsigned short
|
|
Packit |
8dc392 |
half::bits () const
|
|
Packit |
8dc392 |
{
|
|
Packit |
8dc392 |
return _h;
|
|
Packit |
8dc392 |
}
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
inline void
|
|
Packit |
8dc392 |
half::setBits (unsigned short bits)
|
|
Packit |
8dc392 |
{
|
|
Packit |
8dc392 |
_h = bits;
|
|
Packit |
8dc392 |
}
|
|
Packit |
8dc392 |
|
|
Packit |
8dc392 |
#endif
|