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/*
* Copyright (c) 2021 Cisco and/or its affiliates.
* 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.
*/
/**
* \file array.h
* \brief Fixed-size pool allocator
*/
#ifndef UTIL_COMMON_H
#define UTIL_COMMON_H
#define round_pow2(x, pow2) ((x + pow2 - 1) & ~(pow2 - 1))
#define _SIZEOF_ALIGNED(x, size) round_pow2(sizeof(x), size)
#define SIZEOF_ALIGNED(x) _SIZEOF_ALIGNED(x, sizeof(void*))
/* Definitions for builtins unavailable on MSVC */
#if defined(_MSC_VER) && !defined(__clang__)
#include <intrin.h>
uint32_t __inline __builtin_ctz(uint32_t value) {
uint32_t trailing_zero = 0;
if (_BitScanForward(&trailing_zero, value))
return trailing_zero;
else
return 32;
}
uint32_t __inline __builtin_clz(uint32_t value) {
uint32_t leading_zero = 0;
if (_BitScanReverse(&leading_zero, value))
return 31 - leading_zero;
else
return 32;
}
uint32_t __inline __builtin_clzl2(uint64_t value) {
uint32_t leading_zero = 0;
if (_BitScanReverse64(&leading_zero, value))
return 63 - leading_zero;
else
return 64;
}
#define __builtin_clzl __builtin_clzll
#endif
#define next_pow2(x) (x <= 1 ? 1 : 1ul << (64 - __builtin_clzl(x - 1)))
#endif /* UTIL_COMMON_H */
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