1 | /* |
---|
2 | (C) Copyright 2001,2006, |
---|
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 without |
---|
10 | modification, are permitted provided that the following conditions are met: |
---|
11 | |
---|
12 | * Redistributions of source code must retain the above copyright notice, |
---|
13 | this list of conditions and the following disclaimer. |
---|
14 | * Redistributions in binary form must reproduce the above copyright |
---|
15 | notice, this list of conditions and the following disclaimer in the |
---|
16 | documentation and/or other materials provided with the distribution. |
---|
17 | * Neither the names of the copyright holders nor the names of their |
---|
18 | contributors may be used to endorse or promote products derived from this |
---|
19 | software without specific prior written permission. |
---|
20 | |
---|
21 | THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS |
---|
22 | IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED |
---|
23 | TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A |
---|
24 | PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER |
---|
25 | OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
---|
26 | EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
---|
27 | PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR |
---|
28 | PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF |
---|
29 | LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING |
---|
30 | NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS |
---|
31 | SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
---|
32 | */ |
---|
33 | #ifndef _FMIN_H_ |
---|
34 | #define _FMIN_H_ 1 |
---|
35 | |
---|
36 | #include <spu_intrinsics.h> |
---|
37 | #include "headers/vec_literal.h" |
---|
38 | |
---|
39 | /* Return the minimum numeric value of their arguments. If one argument |
---|
40 | * is a NaN, fmin returns the other value. If both are NaNs, then a NaN |
---|
41 | * is returned. |
---|
42 | * |
---|
43 | * Notes: |
---|
44 | * 1) Double precision denorms equate to zero so two denorms compare |
---|
45 | * equal thereby making the following true for two denorm inputs |
---|
46 | * fmin(a, b) != fmin(b, a); |
---|
47 | */ |
---|
48 | |
---|
49 | static __inline double _fmin(double x, double y) |
---|
50 | { |
---|
51 | vec_uint4 nan_x, selector, abs_x, gt, eq; |
---|
52 | vec_uint4 sign = VEC_LITERAL(vec_uint4, 0x80000000, 0, 0x80000000, 0); |
---|
53 | vec_uint4 infinity = VEC_LITERAL(vec_uint4, 0x7FF00000, 0, 0x7FF00000, 0); |
---|
54 | vec_double2 vx, vy, diff, min; |
---|
55 | |
---|
56 | vx = spu_promote(x, 0); |
---|
57 | vy = spu_promote(y, 0); |
---|
58 | |
---|
59 | /* If x is a NaN, then select y as min |
---|
60 | */ |
---|
61 | abs_x = spu_andc((vec_uint4)vx, sign); |
---|
62 | gt = spu_cmpgt(abs_x, infinity); |
---|
63 | eq = spu_cmpeq(abs_x, infinity); |
---|
64 | |
---|
65 | nan_x = spu_or(gt, spu_and(eq, spu_rlqwbyte(gt, 4))); |
---|
66 | |
---|
67 | diff = spu_sub(vy, vx); |
---|
68 | selector = spu_orc(nan_x, spu_cmpgt((vec_int4)diff, -1)); |
---|
69 | selector = spu_maskw(spu_extract(selector, 0)); |
---|
70 | |
---|
71 | min = spu_sel(vx, vy, (vec_ullong2)selector); |
---|
72 | |
---|
73 | return (spu_extract(min, 0)); |
---|
74 | } |
---|
75 | #endif /* _FMIN_H_ */ |
---|