Commit 49caffe0 authored by Peter Maydell's avatar Peter Maydell
Browse files

qemu-common.h: Move muldiv64() to host-utils.h 



Move the muldiv64() function from qemu-common.h to host-utils.h.
This puts it together with all the other arithmetic functions
where we provide a version with __int128_t and a fallback
without, and allows headers which need muldiv64() to avoid
including qemu-common.h.

We don't include host-utils from qemu-common.h, to avoid dragging
more things into qemu-common.h than it already has; in practice
everywhere that needs muldiv64() can get it via qemu/timer.h.

Signed-off-by: default avatarPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: default avatarDaniel P. Berrange <berrange@redhat.com>
parent 03557b9a

include/qemu-common.h

+0 −31
Original line number Diff line number Diff line
@@ -411,37 +411,6 @@ static inline uint8_t from_bcd(uint8_t val) 
    return ((val >> 4) * 10) + (val & 0x0f);

}



/* compute with 96 bit intermediate result: (a*b)/c */

#ifdef CONFIG_INT128

static inline uint64_t muldiv64(uint64_t a, uint32_t b, uint32_t c)

{

    return (__int128_t)a * b / c;

}

#else

static inline uint64_t muldiv64(uint64_t a, uint32_t b, uint32_t c)

{

    union {

        uint64_t ll;

        struct {

#ifdef HOST_WORDS_BIGENDIAN

            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



/* Round number down to multiple */

#define QEMU_ALIGN_DOWN(n, m) ((n) / (m) * (m))

include/qemu/host-utils.h

+29 −0
Original line number Diff line number Diff line
@@ -45,6 +45,12 @@ static inline void muls64(uint64_t *plow, uint64_t *phigh, 
    *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 int divu128(uint64_t *plow, uint64_t *phigh, uint64_t divisor)

{

    if (divisor == 0) {
@@ -75,6 +81,29 @@ void muls64(uint64_t *phigh, uint64_t *plow, int64_t a, int64_t b); 
void mulu64(uint64_t *phigh, uint64_t *plow, uint64_t a, uint64_t b);

int divu128(uint64_t *plow, uint64_t *phigh, uint64_t divisor);

int divs128(int64_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 {

#ifdef HOST_WORDS_BIGENDIAN

            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



/**

include/qemu/timer.h

+1 −0
Original line number Diff line number Diff line
@@ -4,6 +4,7 @@ 
#include "qemu/typedefs.h"

#include "qemu-common.h"

#include "qemu/notify.h"

#include "qemu/host-utils.h"



#define NANOSECONDS_PER_SECOND 1000000000LL