/*
* Utility compute operations used by translated code.
*
* Copyright (c) 2007 Thiemo Seufer
* Copyright (c) 2007 Jocelyn Mayer
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
/* Portions of this work are licensed under the terms of the GNU GPL,
* version 2 or later. See the COPYING file in the top-level directory.
*/
#ifndef HOST_UTILS_H
#define HOST_UTILS_H
#include "qemu/compiler.h"
#include "qemu/bswap.h"
#include "qemu/int128.h"
#ifdef CONFIG_INT128
static inline void mulu64(uint64_t *plow, uint64_t *phigh,
uint64_t a, uint64_t b)
{
__uint128_t r = (__uint128_t)a * b;
*plow = r;
*phigh = r >> 64;
}
static inline void muls64(uint64_t *plow, uint64_t *phigh,
int64_t a, int64_t b)
{
__int128_t r = (__int128_t)a * b;
*plow = r;
*phigh = r >> 64;
}
/* compute with 96 bit intermediate result: (a*b)/c */
static inline uint64_t muldiv64(uint64_t a, uint32_t b, uint32_t c)
{
return (__int128_t)a * b / c;
}
static inline uint64_t divu128(uint64_t *plow, uint64_t *phigh,
uint64_t divisor)
{
__uint128_t dividend = ((__uint128_t)*phigh << 64) | *plow;
__uint128_t result = dividend / divisor;
*plow = result;
*phigh = result >> 64;
return dividend % divisor;
}
static inline int64_t divs128(uint64_t *plow, int64_t *phigh,
int64_t divisor)
{
__int128_t dividend = ((__int128_t)*phigh << 64) | *plow;
__int128_t result = dividend / divisor;
*plow = result;
*phigh = result >> 64;
return dividend % divisor;
}
#else
void muls64(uint64_t *plow, uint64_t *phigh, int64_t a, int64_t b);
void mulu64(uint64_t *plow, uint64_t *phigh, uint64_t a, uint64_t b);
uint64_t divu128(uint64_t *plow, uint64_t *phigh, uint64_t divisor);
int64_t divs128(uint64_t *plow, int64_t *phigh, int64_t divisor);
static inline uint64_t muldiv64(uint64_t a, uint32_t b, uint32_t c)
{
union {
uint64_t ll;
struct {
#if HOST_BIG_ENDIAN
uint32_t high, low;
#else
uint32_t low, high;
#endif
} l;
} u, res;
uint64_t rl, rh;
u.ll = a;
rl = (uint64_t)u.l.low * (uint64_t)b;
rh = (uint64_t)u.l.high * (uint64_t)b;
rh += (rl >> 32);
res.l.high = rh / c;
res.l.low = (((rh % c) << 32) + (rl & 0xffffffff)) / c;
return res.ll;
}
#endif
/**
* clz32 - count leading zeros in a 32-bit value.
* @val: The value to search
*
* Returns 32 if the value is zero. Note that the GCC builtin is
* undefined if the value is zero.
*/
static inline int clz32(uint32_t val)
{
return val ? __builtin_clz(val) : 32;
}
/**
* clo32 - count leading ones in a 32-bit value.
* @val: The value to search
*
* Returns 32 if the value is -1.
*/
static inline int clo32(uint32_t val)
{
return clz32(~val);
}
/**
* clz64 - count leading zeros in a 64-bit value.
* @val: The value to search
*
* Returns 64 if the value is zero. Note that the GCC builtin is
* undefined if the value is zero.
*/
static inline int clz64(uint64_t val)
{
return val ? __builtin_clzll(val) : 64;
}
/**
* clo64 - count leading ones in a 64-bit value.
* @val: The value to search
*
* Returns 64 if the value is -1.
*/
static inline int clo64(uint64_t val)
{
return clz64(~val);
}
/**
* ctz32 - count trailing zeros in a 32-bit value.
* @val: The value to search
*
* Returns 32 if the value is zero. Note that the GCC builtin is
* undefined if the value is zero.
*/
static inline int ctz32(uint32_t val)
{
return val ? __builtin_ctz(val) : 32;
}
/**
* cto32 - count trailing ones in a 32-bit value.
* @val: The value to search
*
* Returns 32 if the value is -1.
*/
static inline int cto32(uint32_t val)
{
return ctz32(~val);
}
/**
* ctz64 - count trailing zeros in a 64-bit value.
* @val: The value to search
*
* Returns 64 if the value is zero. Note that the GCC builtin is
* undefined if the value is zero.
*/
static inline int ctz64(uint64_t val)
{
return val ? __builtin_ctzll(val) : 64;
}
/**
* cto64 - count trailing ones in a 64-bit value.
* @val: The value to search
*
* Returns 64 if the value is -1.
*/
static inline int cto64(uint64_t val)
{
return ctz64(~val);
}
/**
* clrsb32 - count leading redundant sign bits in a 32-bit value.
* @val: The value to search
*
* Returns the number of bits following the sign bit that are equal to it.
* No special cases; output range is [0-31].
*/
static inline int clrsb32(uint32_t val)
{
#if __has_builtin(__builtin_clrsb) || !defined(__clang__)
return __builtin_clrsb(val);
#else
return clz32(val ^ ((int32_t)val >> 1)) - 1;
#endif
}
/**
* clrsb64 - count leading redundant sign bits in a 64-bit value.
* @val: The value to search
*
* Returns the number of bits following the sign bit that are equal to it.
* No special cases; output range is [0-63].
*/
static inline int clrsb64(uint64_t val)
{
#if __has_builtin(__builtin_clrsbll) || !defined(__clang__)
return __builtin_clrsbll(val);
#else
return clz64(val ^ ((int64_t)val >> 1)) - 1;
#endif
}
/**
* ctpop8 - count the population of one bits in an 8-bit value.
* @val: The value to search
*/
static inline int ctpop8(uint8_t val)
{
return __builtin_popcount(val);
}
/**
* ctpop16 - count the population of one bits in a 16-bit value.
* @val: The value to search
*/
static inline int ctpop16(uint16_t val)
{
return __builtin_popcount(val);
}
/**
* ctpop32 - count the population of one bits in a 32-bit value.
* @val: The value to search
*/
static inline int ctpop32(uint32_t val)
{
return __builtin_popcount(val);
}
/**
* ctpop64 - count the population of one bits in a 64-bit value.
* @val: The value to search
*/
static inline int ctpop64(uint64_t val)
{
return __builtin_popcountll(val);
}
/**
* revbit8 - reverse the bits in an 8-bit value.
* @x: The value to modify.
*/
static inline uint8_t revbit8(uint8_t x)
{
#if __has_builtin(__builtin_bitreverse8)
return __builtin_bitreverse8(x);
#else
/* Assign the correct nibble position. */
x = ((x & 0xf0) >> 4)
| ((x & 0x0f) << 4);
/* Assign the correct bit position. */
x = ((x & 0x88) >> 3)
| ((x & 0x44) >> 1)
| ((x & 0x22) << 1)
| ((x & 0x11) << 3);
return x;
#endif
}
/**
* revbit16 - reverse the bits in a 16-bit value.
* @x: The value to modify.
*/
static inline uint16_t revbit16(uint16_t x)
{
#if __has_builtin(__builtin_bitreverse16)
return __builtin_bitreverse16(x);
#else
/* Assign the correct byte position. */
x = bswap16(x);
/* Assign the correct nibble position. */
x = ((x & 0xf0f0) >> 4)
| ((x & 0x0f0f) << 4);
/* Assign the correct bit position. */
x = ((x & 0x8888) >> 3)
| ((x & 0x4444) >> 1)
| ((x & 0x2222) << 1)
| ((x & 0x1111) << 3);
return x;
#endif
}
/**
* revbit32 - reverse the bits in a 32-bit value.
* @x: The value to modify.
*/
static inline uint32_t revbit32(uint32_t x)
{
#if __has_builtin(__builtin_bitreverse32)
return __builtin_bitreverse32(x);
#else
/* Assign the correct byte position. */
x = bswap32(x);
/* Assign the correct nibble position. */
x = ((x & 0xf0f0f0f0u) >> 4)
| ((x & 0x0f0f0f0fu) << 4);
/* Assign the correct bit position. */
x = ((x & 0x88888888u) >> 3)
| ((x & 0x44444444u) >> 1)
| ((x & 0x22222222u) << 1)
| ((x & 0x11111111u) << 3);
return x;
#endif
}
/**
* revbit64 - reverse the bits in a 64-bit value.
* @x: The value to modify.
*/
static inline uint64_t revbit64(uint64_t x)
{
#if __has_builtin(__builtin_bitreverse64)
return __builtin_bitreverse64(x);
#else
/* Assign the correct byte position. */
x = bswap64(x);
/* Assign the correct nibble position. */
x = ((x & 0xf0f0f0f0f0f0f0f0ull) >> 4)
| ((x & 0x0f0f0f0f0f0f0f0full) << 4);
/* Assign the correct bit position. */
x = ((x & 0x8888888888888888ull) >> 3)
| ((x & 0x4444444444444444ull) >> 1)
| ((x & 0x2222222222222222ull) << 1)
| ((x & 0x1111111111111111ull) << 3);
return x;
#endif
}
/**
* Return the absolute value of a 64-bit integer as an unsigned 64-bit value
*/
static inline uint64_t uabs64(int64_t v)
{
return v < 0 ? -v : v;
}
/**
* sadd32_overflow - addition with overflow indication
* @x, @y: addends
* @ret: Output for sum
*
* Computes *@ret = @x + @y, and returns true if and only if that
* value has been truncated.
*/
static inline bool sadd32_overflow(int32_t x, int32_t y, int32_t *ret)
{
return __builtin_add_overflow(x, y, ret);
}
/**
* sadd64_overflow - addition with overflow indication
* @x, @y: addends
* @ret: Output for sum
*
* Computes *@ret = @x + @y, and returns true if and only if that
* value has been truncated.
*/
static inline bool sadd64_overflow(int64_t x, int64_t y, int64_t *ret)
{
return __builtin_add_overflow(x, y, ret);
}
/**
* uadd32_overflow - addition with overflow indication
* @x, @y: addends
* @ret: Output for sum
*
* Computes *@ret = @x + @y, and returns true if and only if that
* value has been truncated.
*/
static inline bool uadd32_overflow(uint32_t x, uint32_t y, uint32_t *ret)
{
return __builtin_add_overflow(x, y, ret);
}
/**
* uadd64_overflow - addition with overflow indication
* @x, @y: addends
* @ret: Output for sum
*
* Computes *@ret = @x + @y, and returns true if and only if that
* value has been truncated.
*/
static inline bool uadd64_overflow(uint64_t x, uint64_t y, uint64_t *ret)
{
return __builtin_add_overflow(x, y, ret);
}
/**
* ssub32_overflow - subtraction with overflow indication
* @x: Minuend
* @y: Subtrahend
* @ret: Output for difference
*
* Computes *@ret = @x - @y, and returns true if and only if that
* value has been truncated.
*/
static inline bool ssub32_overflow(int32_t x, int32_t y, int32_t *ret)
{
return __builtin_sub_overflow(x, y, ret);
}
/**
* ssub64_overflow - subtraction with overflow indication
* @x: Minuend
* @y: Subtrahend
* @ret: Output for sum
*
* Computes *@ret = @x - @y, and returns true if and only if that
* value has been truncated.
*/
static inline bool ssub64_overflow(int64_t x, int64_t y, int64_t *ret)
{
return __builtin_sub_overflow(x, y, ret);
}
/**
* usub32_overflow - subtraction with overflow indication
* @x: Minuend
* @y: Subtrahend
* @ret: Output for sum
*
* Computes *@ret = @x - @y, and returns true if and only if that
* value has been truncated.
*/
static inline bool usub32_overflow(uint32_t x, uint32_t y, uint32_t *ret)
{
return __builtin_sub_overflow(x, y, ret);
}
/**
* usub64_overflow - subtraction with overflow indication
* @x: Minuend
* @y: Subtrahend
* @ret: Output for sum
*
* Computes *@ret = @x - @y, and returns true if and only if that
* value has been truncated.
*/
static inline bool usub64_overflow(uint64_t x, uint64_t y, uint64_t *ret)
{
return __builtin_sub_overflow(x, y, ret);
}
/**
* smul32_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 smul32_overflow(int32_t x, int32_t y, int32_t *ret)
{
return __builtin_mul_overflow(x, y, ret);
}
/**
* 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)
{
return __builtin_mul_overflow(x, y, ret);
}
/**
* 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)
{
return __builtin_mul_overflow(x, y, ret);
}
/**
* 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)
{
return __builtin_mul_overflow(x, y, ret);
}
/*
* Unsigned 128x64 multiplication.
* Returns true if the result got truncated to 128 bits.
* Otherwise, returns false and the multiplication result via plow and phigh.
*/
static inline bool mulu128(uint64_t *plow, uint64_t *phigh, uint64_t factor)
{
#if defined(CONFIG_INT128)
bool res;
__uint128_t r;
__uint128_t f = ((__uint128_t)*phigh << 64) | *plow;
res = __builtin_mul_overflow(f, factor, &r);
*plow = r;
*phigh = r >> 64;
return res;
#else
uint64_t dhi = *phigh;
uint64_t dlo = *plow;
uint64_t ahi;
uint64_t blo, bhi;
if (dhi == 0) {
mulu64(plow, phigh, dlo, factor);
return false;
}
mulu64(plow, &ahi, dlo, factor);
mulu64(&blo, &bhi, dhi, factor);
return uadd64_overflow(ahi, blo, phigh) || bhi != 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);
/* From the GNU Multi Precision Library - longlong.h __udiv_qrnnd
* (https://gmplib.org/repo/gmp/file/tip/longlong.h)
*
* Licensed under the GPLv2/LGPLv3
*/
static inline uint64_t udiv_qrnnd(uint64_t *r, uint64_t n1,
uint64_t n0, uint64_t d)
{
#if defined(__x86_64__)
uint64_t q;
asm("divq %4" : "=a"(q), "=d"(*r) : "0"(n0), "1"(n1), "rm"(d));
return q;
#elif defined(__s390x__) && !defined(__clang__)
/* Need to use a TImode type to get an even register pair for DLGR. */
unsigned __int128 n = (unsigned __int128)n1 << 64 | n0;
asm("dlgr %0, %1" : "+r"(n) : "r"(d));
*r = n >> 64;
return n;
#elif defined(_ARCH_PPC64) && defined(_ARCH_PWR7)
/* From Power ISA 2.06, programming note for divdeu. */
uint64_t q1, q2, Q, r1, r2, R;
asm("divdeu %0,%2,%4; divdu %1,%3,%4"
: "=&r"(q1), "=r"(q2)
: "r"(n1), "r"(n0), "r"(d));
r1 = -(q1 * d); /* low part of (n1<<64) - (q1 * d) */
r2 = n0 - (q2 * d);
Q = q1 + q2;
R = r1 + r2;
if (R >= d || R < r2) { /* overflow implies R > d */
Q += 1;
R -= d;
}
*r = R;
return Q;
#else
uint64_t d0, d1, q0, q1, r1, r0, m;
d0 = (uint32_t)d;
d1 = d >> 32;
r1 = n1 % d1;
q1 = n1 / d1;
m = q1 * d0;
r1 = (r1 << 32) | (n0 >> 32);
if (r1 < m) {
q1 -= 1;
r1 += d;
if (r1 >= d) {
if (r1 < m) {
q1 -= 1;
r1 += d;
}
}
}
r1 -= m;
r0 = r1 % d1;
q0 = r1 / d1;
m = q0 * d0;
r0 = (r0 << 32) | (uint32_t)n0;
if (r0 < m) {
q0 -= 1;
r0 += d;
if (r0 >= d) {
if (r0 < m) {
q0 -= 1;
r0 += d;
}
}
}
r0 -= m;
*r = r0;
return (q1 << 32) | q0;
#endif
}
Int128 divu256(Int128 *plow, Int128 *phigh, Int128 divisor);
Int128 divs256(Int128 *plow, Int128 *phigh, Int128 divisor);
#endif
