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// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2020, 2024, Oracle and/or its affiliates.
*/
#include <linux/bpf.h>
#include <stdint.h>
#include <bpf/bpf_helpers.h>
#ifndef noinline
# define noinline __attribute__((noinline))
#endif
noinline int16_t dt_agg_qbin(int64_t val)
{
int16_t off;
uint64_t tmp;
if (val == 0)
return 63;
if (val == 0x8000000000000000)
return 0;
tmp = val;
if (val < 0)
tmp *= -1;
/* now, tmp has at least one 1, while the leading bit is 0 */
off = 1;
if (tmp & 0x7fffffff00000000) { off += 32; tmp >>= 32; }
if (tmp & 0x00000000ffff0000) { off += 16; tmp >>= 16; }
if (tmp & 0x000000000000ff00) { off += 8; tmp >>= 8; }
if (tmp & 0x00000000000000f0) { off += 4; tmp >>= 4; }
if (tmp & 0x000000000000000c) { off += 2; tmp >>= 2; }
if (tmp & 0x0000000000000002) { off += 1; }
if (val < 0)
off *= -1;
off += 63;
return off;
}
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