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#include <xen/lib.h>
/* Compute with 96 bit intermediate result: (a*b)/c */
uint64_t muldiv64(uint64_t a, uint32_t b, uint32_t c)
{
#ifdef CONFIG_X86
asm ( "mulq %1; divq %2" : "+a" (a)
: "rm" ((uint64_t)b), "rm" ((uint64_t)c)
: "rdx" );
return a;
#else
union {
uint64_t ll;
struct {
#ifdef 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
}
/*
* Local variables:
* mode: C
* c-file-style: "BSD"
* c-basic-offset: 4
* tab-width: 4
* indent-tabs-mode: nil
* End:
*/
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