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#ifndef AWS_COMMON_MATH_GCC_BUILTIN_INL
#define AWS_COMMON_MATH_GCC_BUILTIN_INL
/**
* Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: Apache-2.0.
*/
/*
* This header is already included, but include it again to make editor
* highlighting happier.
*/
#include <aws/common/common.h>
#include <aws/common/math.h>
/* clang-format off */
AWS_EXTERN_C_BEGIN
/**
* Search from the MSB to LSB, looking for a 1
*/
AWS_STATIC_IMPL size_t aws_clz_u32(uint32_t n) {
if (n == 0) {
return sizeof(n) * 8;
}
return __builtin_clz(n);
}
AWS_STATIC_IMPL size_t aws_clz_i32(int32_t n) {
if (n == 0) {
return sizeof(n) * 8;
}
return __builtin_clz(n);
}
AWS_STATIC_IMPL size_t aws_clz_u64(uint64_t n) {
if (n == 0) {
return sizeof(n) * 8;
}
return __builtin_clzll(n);
}
AWS_STATIC_IMPL size_t aws_clz_i64(int64_t n) {
if (n == 0) {
return sizeof(n) * 8;
}
return __builtin_clzll(n);
}
AWS_STATIC_IMPL size_t aws_clz_size(size_t n) {
#if SIZE_BITS == 64
return aws_clz_u64(n);
#else
return aws_clz_u32(n);
#endif
}
/**
* Search from the LSB to MSB, looking for a 1
*/
AWS_STATIC_IMPL size_t aws_ctz_u32(uint32_t n) {
if (n == 0) {
return sizeof(n) * 8;
}
return __builtin_ctzl(n);
}
AWS_STATIC_IMPL size_t aws_ctz_i32(int32_t n) {
if (n == 0) {
return sizeof(n) * 8;
}
return __builtin_ctz(n);
}
AWS_STATIC_IMPL size_t aws_ctz_u64(uint64_t n) {
if (n == 0) {
return sizeof(n) * 8;
}
return __builtin_ctzll(n);
}
AWS_STATIC_IMPL size_t aws_ctz_i64(int64_t n) {
if (n == 0) {
return sizeof(n) * 8;
}
return __builtin_ctzll(n);
}
AWS_STATIC_IMPL size_t aws_ctz_size(size_t n) {
#if SIZE_BITS == 64
return aws_ctz_u64(n);
#else
return aws_ctz_u32(n);
#endif
}
AWS_EXTERN_C_END
/* clang-format on */
#endif /* AWS_COMMON_MATH_GCC_BUILTIN_INL */
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