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Significant speedup for "divu_64x32_rem" by using inline assembly for x86_64 as well.

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- GCC will always call into libgcc to catch overflows.
This commit is contained in:
Couriersud 2012-08-07 00:26:21 +00:00
parent 15a11a0a8a
commit bfb94f1367
1 changed files with 34 additions and 9 deletions
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43
src/emu/eigccx86.h
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@ -27,6 +27,14 @@
INLINE MATH FUNCTIONS
***************************************************************************/
typedef union
{
UINT64 u64;
struct {
UINT32 l, h;
} u32;
} _x86_union;
/*-------------------------------------------------
mul_32x32 - perform a signed 32 bit x 32 bit
multiply and return the full 64 bit result
@ -295,6 +303,29 @@ _divu_64x32_rem(UINT64 dividend, UINT32 divisor, UINT32 *remainder)
return quotient;
}
#else
#define divu_64x32_rem _divu_64x32_rem
INLINE UINT32 ATTR_FORCE_INLINE
_divu_64x32_rem(UINT64 dividend, UINT32 divisor, UINT32 *remainder)
{
register UINT32 quotient;
register _x86_union r;
r.u64 = dividend;
/* Throws arithmetic exception if result doesn't fit in 32 bits */
__asm__ (
" divl %[divisor] ;"
: [result] "=a" (quotient) /* Quotient ends up in eax */
, [remainder] "=d" (*remainder) /* Remainder ends up in edx */
: [divl] "a" (r.u32.l) /* 'dividend' in edx:eax */
, [divh] "d" (r.u32.h)
, [divisor] "rm" (divisor) /* 'divisor' in register or memory */
: "cc" /* Clobbers condition codes */
);
return quotient;
}
#endif
@ -673,19 +704,13 @@ INLINE INT64 ATTR_UNUSED ATTR_FORCE_INLINE _get_profile_ticks(void)
#else
INLINE INT64 ATTR_UNUSED ATTR_FORCE_INLINE _get_profile_ticks(void)
{
union
{
UINT64 r;
struct {
UINT32 r1, r2;
} p;
} r;
_x86_union r;
__asm__ __volatile__ (
"rdtsc"
: "=a" (r.p.r1), "=d" (r.p.r2)
: "=a" (r.u32.l), "=d" (r.u32.h)
);
return (INT64) (r.r & U64(0x7fffffffffffffff));
return (INT64) (r.u64 & U64(0x7fffffffffffffff));
}
#endif