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HyperLogLogRank.h
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1 /*
2  * Copyright 2017 MapD Technologies, Inc.
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 #ifndef QUERYENGINE_HYPERLOGLOGRT_H
18 #define QUERYENGINE_HYPERLOGLOGRT_H
19 
20 #include "../Shared/funcannotations.h"
21 #ifdef _MSC_VER
22 #include <intrin.h>
23 #endif
24 
25 #ifdef __CUDACC__
26 inline __device__ int32_t get_rank(uint64_t x, uint32_t b) {
27  return min(b, static_cast<uint32_t>(x ? __clzll(x) : 64)) + 1;
28 }
29 #else
30 FORCE_INLINE uint8_t get_rank(uint64_t x, uint32_t b) {
31 #ifdef _MSC_VER
32  return std::min(b, static_cast<uint32_t>(x ? __lzcnt64(x) : 64)) + 1;
33 #else
34  return std::min(b, static_cast<uint32_t>(x ? __builtin_clzl(x) : 64)) + 1;
35 #endif
36 }
37 #endif
38 
39 #endif // QUERYENGINE_HYPERLOGLOGRT_H
FORCE_INLINE uint8_t get_rank(uint64_t x, uint32_t b)
#define FORCE_INLINE