Vector Optimized Library of Kernels  2.4
Architecture-tuned implementations of math kernels
bit_utils.h
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1 // Copyright 2017 Google LLC
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 // http://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
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12 // See the License for the specific language governing permissions and
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14 
15 #ifndef CPU_FEATURES_INCLUDE_INTERNAL_BIT_UTILS_H_
16 #define CPU_FEATURES_INCLUDE_INTERNAL_BIT_UTILS_H_
17 
18 #include <assert.h>
19 #include <stdbool.h>
20 #include <stdint.h>
21 
22 #include "cpu_features_macros.h"
23 
25 
26 inline static bool IsBitSet(uint32_t reg, uint32_t bit) {
27  return (reg >> bit) & 0x1;
28 }
29 
30 inline static uint32_t ExtractBitRange(uint32_t reg, uint32_t msb,
31  uint32_t lsb) {
32  const uint64_t bits = msb - lsb + 1ULL;
33  const uint64_t mask = (1ULL << bits) - 1ULL;
34  assert(msb >= lsb);
35  return (reg >> lsb) & mask;
36 }
37 
39 
40 #endif // CPU_FEATURES_INCLUDE_INTERNAL_BIT_UTILS_H_
IsBitSet
static CPU_FEATURES_START_CPP_NAMESPACE bool IsBitSet(uint32_t reg, uint32_t bit)
Definition: bit_utils.h:26
CPU_FEATURES_START_CPP_NAMESPACE
#define CPU_FEATURES_START_CPP_NAMESPACE
Definition: cpu_features_macros.h:114
ExtractBitRange
static uint32_t ExtractBitRange(uint32_t reg, uint32_t msb, uint32_t lsb)
Definition: bit_utils.h:30
cpu_features_macros.h
CPU_FEATURES_END_CPP_NAMESPACE
#define CPU_FEATURES_END_CPP_NAMESPACE
Definition: cpu_features_macros.h:115