src/compiler/glsl/float64.glsl

   1 /*
   2  * The implementations contained in this file are heavily based on the
   3  * implementations found in the Berkeley SoftFloat library. As such, they are
   4  * licensed under the same 3-clause BSD license:
   5  *
   6  * License for Berkeley SoftFloat Release 3e
   7  *
   8  * John R. Hauser
   9  * 2018 January 20
  10  *
  11  * The following applies to the whole of SoftFloat Release 3e as well as to
  12  * each source file individually.
  13  *
  14  * Copyright 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018 The Regents of the
  15  * University of California.  All rights reserved.
  16  *
  17  * Redistribution and use in source and binary forms, with or without
  18  * modification, are permitted provided that the following conditions are met:
  19  *
  20  *  1. Redistributions of source code must retain the above copyright notice,
  21  *     this list of conditions, and the following disclaimer.
  22  *
  23  *  2. Redistributions in binary form must reproduce the above copyright
  24  *     notice, this list of conditions, and the following disclaimer in the
  25  *     documentation and/or other materials provided with the distribution.
  26  *
  27  *  3. Neither the name of the University nor the names of its contributors
  28  *     may be used to endorse or promote products derived from this software
  29  *     without specific prior written permission.
  30  *
  31  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS "AS IS", AND ANY
  32  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  33  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ARE
  34  * DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY
  35  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  36  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  37  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  38  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  39  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  40  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  41 */
  42
  43 #version 430
  44 #extension GL_ARB_gpu_shader_int64 : enable
  45 #extension GL_ARB_shader_bit_encoding : enable
  46
  47 #pragma warning(off)
  48
  49 /* Software IEEE floating-point rounding mode.
  50  * GLSL spec section "4.7.1 Range and Precision":
  51  * The rounding mode cannot be set and is undefined.
  52  * But here, we are able to define the rounding mode at the compilation time.
  53  */
  54 #define FLOAT_ROUND_NEAREST_EVEN    0
  55 #define FLOAT_ROUND_TO_ZERO         1
  56 #define FLOAT_ROUND_DOWN            2
  57 #define FLOAT_ROUND_UP              3
  58 #define FLOAT_ROUNDING_MODE         FLOAT_ROUND_NEAREST_EVEN
  59
  60 /* Absolute value of a Float64 :
  61  * Clear the sign bit
  62  */
  63 uint64_t
  64 __fabs64(uint64_t __a)
  65 {
  66    uvec2 a = unpackUint2x32(__a);
  67    a.y &= 0x7FFFFFFFu;
  68    return packUint2x32(a);
  69 }