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512a0200de
All the kernel header files now use pargma once rather than the ifndef, as the pre-processed C files do not change while header files are protected with pargma once. This will also solve any naming issues caused by ifndef.
42 lines
907 B
C
42 lines
907 B
C
/*
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* Copyright 2020, Data61, CSIRO (ABN 41 687 119 230)
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*
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* SPDX-License-Identifier: GPL-2.0-only
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*/
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#pragma once
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#include <config.h>
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#include <types.h>
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#include <arch/model/statedata.h>
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static inline CONST uint64_t div64(uint64_t numerator, uint32_t denominator)
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{
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uint64_t quotient = 0llu;
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uint64_t long_denom = (uint64_t) denominator;
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if (unlikely(denominator > numerator)) {
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return 0;
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}
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assert(numerator > 0);
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assert(denominator > 0);
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/* align denominator to numerator */
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uint64_t c = ((uint64_t) 32u + clzl(denominator)) - clzll(numerator);
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long_denom = long_denom << c;
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/* perform binary long division */
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while (c < UINT64_MAX) {
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if (numerator >= long_denom) {
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numerator -= long_denom;
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quotient |= (1llu << c);
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}
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c--;
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long_denom = long_denom >> 1llu;
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}
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return quotient;
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}
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