732 lines
18 KiB
C
732 lines
18 KiB
C
/*
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* Utility compute operations used by translated code.
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*
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* Copyright (c) 2007 Thiemo Seufer
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* Copyright (c) 2007 Jocelyn Mayer
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this software and associated documentation files (the "Software"), to deal
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* in the Software without restriction, including without limitation the rights
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* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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* THE SOFTWARE.
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*/
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#ifndef HOST_UTILS_H
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#define HOST_UTILS_H
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#include "qemu/compiler.h"
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#include "qemu/bswap.h"
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#ifdef CONFIG_INT128
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static inline void mulu64(uint64_t *plow, uint64_t *phigh,
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uint64_t a, uint64_t b)
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{
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__uint128_t r = (__uint128_t)a * b;
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*plow = r;
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*phigh = r >> 64;
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}
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static inline void muls64(uint64_t *plow, uint64_t *phigh,
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int64_t a, int64_t b)
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{
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__int128_t r = (__int128_t)a * b;
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*plow = r;
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*phigh = r >> 64;
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}
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/* compute with 96 bit intermediate result: (a*b)/c */
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static inline uint64_t muldiv64(uint64_t a, uint32_t b, uint32_t c)
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{
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return (__int128_t)a * b / c;
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}
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static inline int divu128(uint64_t *plow, uint64_t *phigh, uint64_t divisor)
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{
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if (divisor == 0) {
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return 1;
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} else {
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__uint128_t dividend = ((__uint128_t)*phigh << 64) | *plow;
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__uint128_t result = dividend / divisor;
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*plow = result;
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*phigh = dividend % divisor;
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return result > UINT64_MAX;
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}
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}
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static inline int divs128(int64_t *plow, int64_t *phigh, int64_t divisor)
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{
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if (divisor == 0) {
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return 1;
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} else {
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__int128_t dividend = ((__int128_t)*phigh << 64) | *plow;
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__int128_t result = dividend / divisor;
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*plow = result;
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*phigh = dividend % divisor;
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return result != *plow;
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}
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}
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#else
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void muls64(uint64_t *plow, uint64_t *phigh, int64_t a, int64_t b);
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void mulu64(uint64_t *plow, uint64_t *phigh, uint64_t a, uint64_t b);
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int divu128(uint64_t *plow, uint64_t *phigh, uint64_t divisor);
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int divs128(int64_t *plow, int64_t *phigh, int64_t divisor);
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static inline uint64_t muldiv64(uint64_t a, uint32_t b, uint32_t c)
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{
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union {
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uint64_t ll;
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struct {
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#ifdef HOST_WORDS_BIGENDIAN
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uint32_t high, low;
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#else
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uint32_t low, high;
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#endif
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} l;
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} u, res;
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uint64_t rl, rh;
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u.ll = a;
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rl = (uint64_t)u.l.low * (uint64_t)b;
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rh = (uint64_t)u.l.high * (uint64_t)b;
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rh += (rl >> 32);
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res.l.high = rh / c;
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res.l.low = (((rh % c) << 32) + (rl & 0xffffffff)) / c;
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return res.ll;
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}
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#endif
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/**
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* clz32 - count leading zeros in a 32-bit value.
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* @val: The value to search
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*
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* Returns 32 if the value is zero. Note that the GCC builtin is
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* undefined if the value is zero.
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*/
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static inline int clz32(uint32_t val)
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{
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return val ? __builtin_clz(val) : 32;
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}
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/**
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* clo32 - count leading ones in a 32-bit value.
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* @val: The value to search
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*
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* Returns 32 if the value is -1.
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*/
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static inline int clo32(uint32_t val)
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{
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return clz32(~val);
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}
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/**
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* clz64 - count leading zeros in a 64-bit value.
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* @val: The value to search
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*
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* Returns 64 if the value is zero. Note that the GCC builtin is
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* undefined if the value is zero.
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*/
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static inline int clz64(uint64_t val)
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{
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return val ? __builtin_clzll(val) : 64;
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}
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/**
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* clo64 - count leading ones in a 64-bit value.
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* @val: The value to search
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*
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* Returns 64 if the value is -1.
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*/
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static inline int clo64(uint64_t val)
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{
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return clz64(~val);
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}
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/**
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* ctz32 - count trailing zeros in a 32-bit value.
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* @val: The value to search
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*
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* Returns 32 if the value is zero. Note that the GCC builtin is
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* undefined if the value is zero.
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*/
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static inline int ctz32(uint32_t val)
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{
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return val ? __builtin_ctz(val) : 32;
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}
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/**
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* cto32 - count trailing ones in a 32-bit value.
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* @val: The value to search
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*
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* Returns 32 if the value is -1.
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*/
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static inline int cto32(uint32_t val)
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{
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return ctz32(~val);
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}
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/**
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* ctz64 - count trailing zeros in a 64-bit value.
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* @val: The value to search
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*
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* Returns 64 if the value is zero. Note that the GCC builtin is
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* undefined if the value is zero.
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*/
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static inline int ctz64(uint64_t val)
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{
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return val ? __builtin_ctzll(val) : 64;
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}
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/**
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* cto64 - count trailing ones in a 64-bit value.
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* @val: The value to search
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*
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* Returns 64 if the value is -1.
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*/
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static inline int cto64(uint64_t val)
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{
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return ctz64(~val);
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}
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/**
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* clrsb32 - count leading redundant sign bits in a 32-bit value.
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* @val: The value to search
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*
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* Returns the number of bits following the sign bit that are equal to it.
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* No special cases; output range is [0-31].
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*/
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static inline int clrsb32(uint32_t val)
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{
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#if __has_builtin(__builtin_clrsb) || !defined(__clang__)
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return __builtin_clrsb(val);
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#else
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return clz32(val ^ ((int32_t)val >> 1)) - 1;
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#endif
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}
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/**
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* clrsb64 - count leading redundant sign bits in a 64-bit value.
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* @val: The value to search
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*
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* Returns the number of bits following the sign bit that are equal to it.
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* No special cases; output range is [0-63].
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*/
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static inline int clrsb64(uint64_t val)
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{
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#if __has_builtin(__builtin_clrsbll) || !defined(__clang__)
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return __builtin_clrsbll(val);
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#else
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return clz64(val ^ ((int64_t)val >> 1)) - 1;
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#endif
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}
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/**
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* ctpop8 - count the population of one bits in an 8-bit value.
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* @val: The value to search
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*/
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static inline int ctpop8(uint8_t val)
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{
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return __builtin_popcount(val);
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}
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/**
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* ctpop16 - count the population of one bits in a 16-bit value.
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* @val: The value to search
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*/
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static inline int ctpop16(uint16_t val)
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{
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return __builtin_popcount(val);
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}
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/**
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* ctpop32 - count the population of one bits in a 32-bit value.
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* @val: The value to search
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*/
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static inline int ctpop32(uint32_t val)
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{
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return __builtin_popcount(val);
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}
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/**
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* ctpop64 - count the population of one bits in a 64-bit value.
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* @val: The value to search
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*/
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static inline int ctpop64(uint64_t val)
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{
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return __builtin_popcountll(val);
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}
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/**
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* revbit8 - reverse the bits in an 8-bit value.
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* @x: The value to modify.
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*/
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static inline uint8_t revbit8(uint8_t x)
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{
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#if __has_builtin(__builtin_bitreverse8)
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return __builtin_bitreverse8(x);
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#else
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/* Assign the correct nibble position. */
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x = ((x & 0xf0) >> 4)
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| ((x & 0x0f) << 4);
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/* Assign the correct bit position. */
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x = ((x & 0x88) >> 3)
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| ((x & 0x44) >> 1)
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| ((x & 0x22) << 1)
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| ((x & 0x11) << 3);
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return x;
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#endif
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}
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/**
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* revbit16 - reverse the bits in a 16-bit value.
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* @x: The value to modify.
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*/
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static inline uint16_t revbit16(uint16_t x)
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{
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#if __has_builtin(__builtin_bitreverse16)
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return __builtin_bitreverse16(x);
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#else
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/* Assign the correct byte position. */
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x = bswap16(x);
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/* Assign the correct nibble position. */
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x = ((x & 0xf0f0) >> 4)
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| ((x & 0x0f0f) << 4);
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/* Assign the correct bit position. */
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x = ((x & 0x8888) >> 3)
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| ((x & 0x4444) >> 1)
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| ((x & 0x2222) << 1)
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| ((x & 0x1111) << 3);
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return x;
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#endif
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}
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/**
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* revbit32 - reverse the bits in a 32-bit value.
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* @x: The value to modify.
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*/
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static inline uint32_t revbit32(uint32_t x)
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{
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#if __has_builtin(__builtin_bitreverse32)
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return __builtin_bitreverse32(x);
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#else
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/* Assign the correct byte position. */
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x = bswap32(x);
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/* Assign the correct nibble position. */
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x = ((x & 0xf0f0f0f0u) >> 4)
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| ((x & 0x0f0f0f0fu) << 4);
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/* Assign the correct bit position. */
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x = ((x & 0x88888888u) >> 3)
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| ((x & 0x44444444u) >> 1)
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| ((x & 0x22222222u) << 1)
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| ((x & 0x11111111u) << 3);
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return x;
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#endif
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}
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/**
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* revbit64 - reverse the bits in a 64-bit value.
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* @x: The value to modify.
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*/
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static inline uint64_t revbit64(uint64_t x)
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{
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#if __has_builtin(__builtin_bitreverse64)
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return __builtin_bitreverse64(x);
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#else
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/* Assign the correct byte position. */
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x = bswap64(x);
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/* Assign the correct nibble position. */
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x = ((x & 0xf0f0f0f0f0f0f0f0ull) >> 4)
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| ((x & 0x0f0f0f0f0f0f0f0full) << 4);
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/* Assign the correct bit position. */
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x = ((x & 0x8888888888888888ull) >> 3)
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| ((x & 0x4444444444444444ull) >> 1)
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| ((x & 0x2222222222222222ull) << 1)
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| ((x & 0x1111111111111111ull) << 3);
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return x;
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#endif
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}
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/**
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* sadd32_overflow - addition with overflow indication
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* @x, @y: addends
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* @ret: Output for sum
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*
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* Computes *@ret = @x + @y, and returns true if and only if that
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* value has been truncated.
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*/
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static inline bool sadd32_overflow(int32_t x, int32_t y, int32_t *ret)
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{
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#if __has_builtin(__builtin_add_overflow) || __GNUC__ >= 5
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return __builtin_add_overflow(x, y, ret);
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#else
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*ret = x + y;
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return ((*ret ^ x) & ~(x ^ y)) < 0;
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#endif
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}
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/**
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* sadd64_overflow - addition with overflow indication
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* @x, @y: addends
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* @ret: Output for sum
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*
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* Computes *@ret = @x + @y, and returns true if and only if that
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* value has been truncated.
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*/
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static inline bool sadd64_overflow(int64_t x, int64_t y, int64_t *ret)
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{
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#if __has_builtin(__builtin_add_overflow) || __GNUC__ >= 5
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return __builtin_add_overflow(x, y, ret);
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#else
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*ret = x + y;
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return ((*ret ^ x) & ~(x ^ y)) < 0;
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#endif
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}
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/**
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* uadd32_overflow - addition with overflow indication
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* @x, @y: addends
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* @ret: Output for sum
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*
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* Computes *@ret = @x + @y, and returns true if and only if that
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* value has been truncated.
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*/
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static inline bool uadd32_overflow(uint32_t x, uint32_t y, uint32_t *ret)
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{
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#if __has_builtin(__builtin_add_overflow) || __GNUC__ >= 5
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return __builtin_add_overflow(x, y, ret);
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#else
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*ret = x + y;
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return *ret < x;
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#endif
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}
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/**
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* uadd64_overflow - addition with overflow indication
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* @x, @y: addends
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* @ret: Output for sum
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*
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* Computes *@ret = @x + @y, and returns true if and only if that
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* value has been truncated.
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*/
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static inline bool uadd64_overflow(uint64_t x, uint64_t y, uint64_t *ret)
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{
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#if __has_builtin(__builtin_add_overflow) || __GNUC__ >= 5
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return __builtin_add_overflow(x, y, ret);
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#else
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*ret = x + y;
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return *ret < x;
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#endif
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}
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/**
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* ssub32_overflow - subtraction with overflow indication
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* @x: Minuend
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* @y: Subtrahend
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* @ret: Output for difference
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*
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* Computes *@ret = @x - @y, and returns true if and only if that
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* value has been truncated.
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*/
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static inline bool ssub32_overflow(int32_t x, int32_t y, int32_t *ret)
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{
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#if __has_builtin(__builtin_sub_overflow) || __GNUC__ >= 5
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return __builtin_sub_overflow(x, y, ret);
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#else
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*ret = x - y;
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return ((*ret ^ x) & (x ^ y)) < 0;
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#endif
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}
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/**
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* ssub64_overflow - subtraction with overflow indication
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* @x: Minuend
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* @y: Subtrahend
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* @ret: Output for sum
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*
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* Computes *@ret = @x - @y, and returns true if and only if that
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* value has been truncated.
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*/
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static inline bool ssub64_overflow(int64_t x, int64_t y, int64_t *ret)
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{
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#if __has_builtin(__builtin_sub_overflow) || __GNUC__ >= 5
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return __builtin_sub_overflow(x, y, ret);
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#else
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*ret = x - y;
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return ((*ret ^ x) & (x ^ y)) < 0;
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#endif
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}
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/**
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* usub32_overflow - subtraction with overflow indication
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* @x: Minuend
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* @y: Subtrahend
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* @ret: Output for sum
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*
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* Computes *@ret = @x - @y, and returns true if and only if that
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* value has been truncated.
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*/
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static inline bool usub32_overflow(uint32_t x, uint32_t y, uint32_t *ret)
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{
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#if __has_builtin(__builtin_sub_overflow) || __GNUC__ >= 5
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return __builtin_sub_overflow(x, y, ret);
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#else
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*ret = x - y;
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return x < y;
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#endif
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}
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/**
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* usub64_overflow - subtraction with overflow indication
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* @x: Minuend
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* @y: Subtrahend
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* @ret: Output for sum
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*
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* Computes *@ret = @x - @y, and returns true if and only if that
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* value has been truncated.
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*/
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static inline bool usub64_overflow(uint64_t x, uint64_t y, uint64_t *ret)
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{
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#if __has_builtin(__builtin_sub_overflow) || __GNUC__ >= 5
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return __builtin_sub_overflow(x, y, ret);
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#else
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*ret = x - y;
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return x < y;
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#endif
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}
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/**
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* smul32_overflow - multiplication with overflow indication
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* @x, @y: Input multipliers
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* @ret: Output for product
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*
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* Computes *@ret = @x * @y, and returns true if and only if that
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* value has been truncated.
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*/
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static inline bool smul32_overflow(int32_t x, int32_t y, int32_t *ret)
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{
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|
#if __has_builtin(__builtin_mul_overflow) || __GNUC__ >= 5
|
|
return __builtin_mul_overflow(x, y, ret);
|
|
#else
|
|
int64_t z = (int64_t)x * y;
|
|
*ret = z;
|
|
return *ret != z;
|
|
#endif
|
|
}
|
|
|
|
/**
|
|
* smul64_overflow - multiplication with overflow indication
|
|
* @x, @y: Input multipliers
|
|
* @ret: Output for product
|
|
*
|
|
* Computes *@ret = @x * @y, and returns true if and only if that
|
|
* value has been truncated.
|
|
*/
|
|
static inline bool smul64_overflow(int64_t x, int64_t y, int64_t *ret)
|
|
{
|
|
#if __has_builtin(__builtin_mul_overflow) || __GNUC__ >= 5
|
|
return __builtin_mul_overflow(x, y, ret);
|
|
#else
|
|
uint64_t hi, lo;
|
|
muls64(&lo, &hi, x, y);
|
|
*ret = lo;
|
|
return hi != ((int64_t)lo >> 63);
|
|
#endif
|
|
}
|
|
|
|
/**
|
|
* umul32_overflow - multiplication with overflow indication
|
|
* @x, @y: Input multipliers
|
|
* @ret: Output for product
|
|
*
|
|
* Computes *@ret = @x * @y, and returns true if and only if that
|
|
* value has been truncated.
|
|
*/
|
|
static inline bool umul32_overflow(uint32_t x, uint32_t y, uint32_t *ret)
|
|
{
|
|
#if __has_builtin(__builtin_mul_overflow) || __GNUC__ >= 5
|
|
return __builtin_mul_overflow(x, y, ret);
|
|
#else
|
|
uint64_t z = (uint64_t)x * y;
|
|
*ret = z;
|
|
return z > UINT32_MAX;
|
|
#endif
|
|
}
|
|
|
|
/**
|
|
* umul64_overflow - multiplication with overflow indication
|
|
* @x, @y: Input multipliers
|
|
* @ret: Output for product
|
|
*
|
|
* Computes *@ret = @x * @y, and returns true if and only if that
|
|
* value has been truncated.
|
|
*/
|
|
static inline bool umul64_overflow(uint64_t x, uint64_t y, uint64_t *ret)
|
|
{
|
|
#if __has_builtin(__builtin_mul_overflow) || __GNUC__ >= 5
|
|
return __builtin_mul_overflow(x, y, ret);
|
|
#else
|
|
uint64_t hi;
|
|
mulu64(ret, &hi, x, y);
|
|
return hi != 0;
|
|
#endif
|
|
}
|
|
|
|
/**
|
|
* uadd64_carry - addition with carry-in and carry-out
|
|
* @x, @y: addends
|
|
* @pcarry: in-out carry value
|
|
*
|
|
* Computes @x + @y + *@pcarry, placing the carry-out back
|
|
* into *@pcarry and returning the 64-bit sum.
|
|
*/
|
|
static inline uint64_t uadd64_carry(uint64_t x, uint64_t y, bool *pcarry)
|
|
{
|
|
#if __has_builtin(__builtin_addcll)
|
|
unsigned long long c = *pcarry;
|
|
x = __builtin_addcll(x, y, c, &c);
|
|
*pcarry = c & 1;
|
|
return x;
|
|
#else
|
|
bool c = *pcarry;
|
|
/* This is clang's internal expansion of __builtin_addc. */
|
|
c = uadd64_overflow(x, c, &x);
|
|
c |= uadd64_overflow(x, y, &x);
|
|
*pcarry = c;
|
|
return x;
|
|
#endif
|
|
}
|
|
|
|
/**
|
|
* usub64_borrow - subtraction with borrow-in and borrow-out
|
|
* @x, @y: addends
|
|
* @pborrow: in-out borrow value
|
|
*
|
|
* Computes @x - @y - *@pborrow, placing the borrow-out back
|
|
* into *@pborrow and returning the 64-bit sum.
|
|
*/
|
|
static inline uint64_t usub64_borrow(uint64_t x, uint64_t y, bool *pborrow)
|
|
{
|
|
#if __has_builtin(__builtin_subcll)
|
|
unsigned long long b = *pborrow;
|
|
x = __builtin_subcll(x, y, b, &b);
|
|
*pborrow = b & 1;
|
|
return x;
|
|
#else
|
|
bool b = *pborrow;
|
|
b = usub64_overflow(x, b, &x);
|
|
b |= usub64_overflow(x, y, &x);
|
|
*pborrow = b;
|
|
return x;
|
|
#endif
|
|
}
|
|
|
|
/* Host type specific sizes of these routines. */
|
|
|
|
#if ULONG_MAX == UINT32_MAX
|
|
# define clzl clz32
|
|
# define ctzl ctz32
|
|
# define clol clo32
|
|
# define ctol cto32
|
|
# define ctpopl ctpop32
|
|
# define revbitl revbit32
|
|
#elif ULONG_MAX == UINT64_MAX
|
|
# define clzl clz64
|
|
# define ctzl ctz64
|
|
# define clol clo64
|
|
# define ctol cto64
|
|
# define ctpopl ctpop64
|
|
# define revbitl revbit64
|
|
#else
|
|
# error Unknown sizeof long
|
|
#endif
|
|
|
|
static inline bool is_power_of_2(uint64_t value)
|
|
{
|
|
if (!value) {
|
|
return false;
|
|
}
|
|
|
|
return !(value & (value - 1));
|
|
}
|
|
|
|
/**
|
|
* Return @value rounded down to the nearest power of two or zero.
|
|
*/
|
|
static inline uint64_t pow2floor(uint64_t value)
|
|
{
|
|
if (!value) {
|
|
/* Avoid undefined shift by 64 */
|
|
return 0;
|
|
}
|
|
return 0x8000000000000000ull >> clz64(value);
|
|
}
|
|
|
|
/*
|
|
* Return @value rounded up to the nearest power of two modulo 2^64.
|
|
* This is *zero* for @value > 2^63, so be careful.
|
|
*/
|
|
static inline uint64_t pow2ceil(uint64_t value)
|
|
{
|
|
int n = clz64(value - 1);
|
|
|
|
if (!n) {
|
|
/*
|
|
* @value - 1 has no leading zeroes, thus @value - 1 >= 2^63
|
|
* Therefore, either @value == 0 or @value > 2^63.
|
|
* If it's 0, return 1, else return 0.
|
|
*/
|
|
return !value;
|
|
}
|
|
return 0x8000000000000000ull >> (n - 1);
|
|
}
|
|
|
|
static inline uint32_t pow2roundup32(uint32_t x)
|
|
{
|
|
x |= (x >> 1);
|
|
x |= (x >> 2);
|
|
x |= (x >> 4);
|
|
x |= (x >> 8);
|
|
x |= (x >> 16);
|
|
return x + 1;
|
|
}
|
|
|
|
/**
|
|
* urshift - 128-bit Unsigned Right Shift.
|
|
* @plow: in/out - lower 64-bit integer.
|
|
* @phigh: in/out - higher 64-bit integer.
|
|
* @shift: in - bytes to shift, between 0 and 127.
|
|
*
|
|
* Result is zero-extended and stored in plow/phigh, which are
|
|
* input/output variables. Shift values outside the range will
|
|
* be mod to 128. In other words, the caller is responsible to
|
|
* verify/assert both the shift range and plow/phigh pointers.
|
|
*/
|
|
void urshift(uint64_t *plow, uint64_t *phigh, int32_t shift);
|
|
|
|
/**
|
|
* ulshift - 128-bit Unsigned Left Shift.
|
|
* @plow: in/out - lower 64-bit integer.
|
|
* @phigh: in/out - higher 64-bit integer.
|
|
* @shift: in - bytes to shift, between 0 and 127.
|
|
* @overflow: out - true if any 1-bit is shifted out.
|
|
*
|
|
* Result is zero-extended and stored in plow/phigh, which are
|
|
* input/output variables. Shift values outside the range will
|
|
* be mod to 128. In other words, the caller is responsible to
|
|
* verify/assert both the shift range and plow/phigh pointers.
|
|
*/
|
|
void ulshift(uint64_t *plow, uint64_t *phigh, int32_t shift, bool *overflow);
|
|
|
|
#endif
|