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/*
* 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 itype ilogb(vtype x) {
utype ux = as_utype(x);
utype ax = ux & (utype)EXSIGNBIT_SP32;
itype rs = (itype)-118 - convert_itype(clz(ux & (utype)MANTBITS_SP32));
itype r = as_itype(ax >> EXPSHIFTBITS_SP32) - (itype)EXPBIAS_SP32;
r = (ax < (utype)0x00800000U) ? rs : r;
r = ((ax > (utype)EXPBITS_SP32) | (ax == (utype)0)) ? (itype)0x80000000 : r;
r = (ax == (utype)EXPBITS_SP32) ? (itype)0x7fffffff : r;
return r;
}
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