1 /*
2 * Copyright (c) 2017, NVIDIA CORPORATION. All rights reserved.
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 *
16 */
17
18 #include "mthdecls.h"
19
20 /* should handle 0**0 w/ exception */
21 float
__mth_i_rpowk(float x,long long i)22 __mth_i_rpowk(float x, long long i)
23 {
24 long long k;
25 float f;
26
27 f = 1;
28 k = i;
29 if (k < 0)
30 k = -k;
31 for (;;) {
32 if (k & 1)
33 f *= x;
34 k >>= 1;
35 if (k == 0)
36 break;
37 x *= x;
38 }
39 if (i < 0)
40 f = 1.0f / f;
41 return f;
42 }
43