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/*
* Copyright (c) 2014-2017, NVIDIA CORPORATION. All rights reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
typedef union {
float f;
unsigned int i;
} FPI;
#define EXPBIAS 127
#define MANTBITS 23
#define GET_EXP(u) (int)(((u)&0x7fffffff) >> MANTBITS)
float
__mth_i_aint(float xx)
{
unsigned int ux, mask;
int xexp;
float x;
FPI fpi;
x = xx;
fpi.f = x;
ux = fpi.i;
xexp = GET_EXP(ux) - EXPBIAS;
if (xexp < 0) {
/* |x| < 0 => zero with the original sign */
fpi.i = ux & 0x80000000;
} else if (xexp < MANTBITS) {
/* 1 <= |x| < 2^24:
* just mask out the trailing bits of the mantissa beyond the
* range of the exponent; mask out the exponent field as well.
*/
mask = (1 << (MANTBITS - xexp)) - 1;
fpi.i = ux & ~mask;
}
/* else for illegal input, nan, inf, overflow, ...; just return it */
return fpi.f;
}
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