1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
|
/*
* Copyright (c) 2015 Advanced Micro Devices, Inc.
* Copyright (c) 2016 Aaron Watry
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
_CL_OVERLOADABLE inttype ilogb(vtype x) {
utype ux = as_utype(x);
utype ax = ux & (utype)(~SIGNBIT_DP64);
inttype r = convert_inttype(ax >> EXPSHIFTBITS_DP64) - (inttype)EXPBIAS_DP64;
inttype rs = (inttype)-1011 - convert_inttype(clz(ax & (utype)MANTBITS_DP64));
r = (ax < (utype)0x0010000000000000UL) ? rs : r;
r = (ax > (utype)0x7ff0000000000000UL) | (ax == (utype)0UL) ? (utype)0x80000000 : r;
r = (ax == (utype)0x7ff0000000000000UL) ? (utype)0x7fffffff : r;
return r;
}
|
