OpenCores
URL https://opencores.org/ocsvn/openrisc_me/openrisc_me/trunk

Subversion Repositories openrisc_me

[/] [openrisc/] [trunk/] [gnu-src/] [newlib-1.18.0/] [newlib/] [libm/] [machine/] [spu/] [headers/] [powd2.h] - Blame information for rev 207

Details | Compare with Previous | View Log

Line No. Rev Author Line
1 207 jeremybenn
/* --------------------------------------------------------------  */
2
/* (C)Copyright 2001,2008,                                         */
3
/* International Business Machines Corporation,                    */
4
/* Sony Computer Entertainment, Incorporated,                      */
5
/* Toshiba Corporation,                                            */
6
/*                                                                 */
7
/* All Rights Reserved.                                            */
8
/*                                                                 */
9
/* Redistribution and use in source and binary forms, with or      */
10
/* without modification, are permitted provided that the           */
11
/* following conditions are met:                                   */
12
/*                                                                 */
13
/* - Redistributions of source code must retain the above copyright*/
14
/*   notice, this list of conditions and the following disclaimer. */
15
/*                                                                 */
16
/* - Redistributions in binary form must reproduce the above       */
17
/*   copyright notice, this list of conditions and the following   */
18
/*   disclaimer in the documentation and/or other materials        */
19
/*   provided with the distribution.                               */
20
/*                                                                 */
21
/* - Neither the name of IBM Corporation nor the names of its      */
22
/*   contributors may be used to endorse or promote products       */
23
/*   derived from this software without specific prior written     */
24
/*   permission.                                                   */
25
/*                                                                 */
26
/* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND          */
27
/* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,     */
28
/* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF        */
29
/* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE        */
30
/* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR            */
31
/* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,    */
32
/* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT    */
33
/* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;    */
34
/* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)        */
35
/* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN       */
36
/* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR    */
37
/* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,  */
38
/* EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.              */
39
/* --------------------------------------------------------------  */
40
/* PROLOG END TAG zYx                                              */
41
#ifdef __SPU__
42
#ifndef _POWD2_H_
43
#define _POWD2_H_       1
44
 
45
#include "exp2d2.h"
46
#include "log2d2.h"
47
 
48
/*
49
 * FUNCTION
50
 *      vector double _powd2(vector double x, vector double y)
51
 *
52
 * DESCRIPTION
53
 *      The _powd2 function computes x raised to the power y for the set of
54
 *      vectors. The powd2 function is computed as by decomposing
55
 *      the problem into:
56
 *
57
 *              x^y = 2^(y*log2(x))
58
 *
59
 *
60
 */
61
static __inline vector double _powd2(vector double x, vector double y)
62
{
63
  vec_uchar16 splat_hi = (vec_uchar16) { 0,1,2,3,0,1,2,3, 8,9,10,11, 8,9,10,11 };
64
  vec_int4 exp, shift;
65
  vec_uint4 sign = (vec_uint4) { 0x80000000, 0, 0x80000000, 0 };
66
  vec_uint4 or_mask, and_mask, evenmask, intmask;
67
  vec_double2 in_hi;
68
  vector double signmask = spu_splats(-0.0);
69
  vector signed int error = spu_splats(-1);
70
  vector double zero = spu_splats(0.0);
71
  vector unsigned int y_is_int, y_is_odd, y_is_even;
72
  vector unsigned int x_is_neg;
73
  vector double xabs, xsign;
74
  vector double out;
75
 
76
 
77
  xsign = spu_and(x, signmask);
78
  xabs  = spu_andc(x, signmask);
79
  x_is_neg = (vec_uint4)spu_cmpgt(zero, x);
80
 
81
 
82
  /* First we solve assuming x was non-negative */
83
  out = _exp2d2(spu_mul(y, _log2d2(xabs)));
84
 
85
  in_hi = spu_shuffle(y, y, splat_hi);
86
  exp = spu_and(spu_rlmask((vec_int4)in_hi, -20), 0x7FF);
87
 
88
  /* Determine if y is an integer */
89
  shift = spu_sub(((vec_int4) { 1023, 1043, 1023, 1043 }), exp);
90
  or_mask = spu_andc(spu_cmpgt(shift, 0), sign);
91
  and_mask = spu_rlmask(((vec_uint4) { 0xFFFFF, -1, 0xFFFFF, -1 }), shift);
92
  intmask = spu_or(spu_and(and_mask, spu_cmpgt(shift, -32)), or_mask);
93
  y_is_int = (vec_uint4)spu_cmpeq(y, spu_andc(y, (vec_double2)(intmask)));
94
 
95
  /* Determine if y is an even integer */
96
  shift = spu_sub(((vec_int4) { 1024, 1044, 1024, 1044 }), exp);
97
  or_mask = spu_andc(spu_cmpgt(shift, 0), sign);
98
  and_mask = spu_rlmask(((vec_uint4) { 0xFFFFF, -1, 0xFFFFF, -1 }), shift);
99
  evenmask = spu_or(spu_and(and_mask, spu_cmpgt(shift, -32)), or_mask);
100
  y_is_even = (vec_uint4)spu_cmpeq(y, spu_andc(y, (vec_double2)(evenmask)));
101
 
102
  y_is_odd = spu_andc(y_is_int, y_is_even);
103
 
104
 
105
  /* Special Cases
106
   */
107
 
108
  /* x < 0 is only ok when y integer */
109
  out = spu_sel(out, (vec_double2)error, (vec_ullong2)spu_andc(x_is_neg, y_is_int));
110
 
111
  /* Preserve the sign of x if y is an odd integer */
112
  out = spu_sel(out, spu_or(out, xsign), (vec_ullong2)y_is_odd);
113
 
114
  /* x = anything, y = +/- 0, returns 1 */
115
  out = spu_sel(out, spu_splats(1.0), spu_cmpabseq(y, zero));
116
 
117
  return(out);
118
}
119
 
120
#endif /* _POWD2_H_ */
121
#endif /* __SPU__ */

powered by: WebSVN 2.1.0

© copyright 1999-2024 OpenCores.org, equivalent to Oliscience, all rights reserved. OpenCores®, registered trademark.