muldi3, divdi3 and remdi3 patterns

[Mark Klein]

At 11:04 PM 8/8/99 -0600, Jeffrey A Law wrote:

>  > In adding muldi3, divdi3 and remdi3 instruction patterns, I find 
>  > that the compiler is choosing to do remsi3 as a widened X-Y*(X/Y)
>  > instead of simply using the remsi3 pattern. It starts down this
>  > path in expand_divmod when expand_mult_highpart recognizes it can
>  > use the muldi3 pattern. 

>Yes.  This is the division by using widening multiplications.  This is
>precisely what I would expect the compiler to do.

So even though $$remoI is faster than the combination of $$mulo2I and
the shifting, on PA we'll get the less efficient implementation? I
don't quite understand how the current costs have been allocated .. is
there a way to influence this such that I'll use the modulo millicode
instead of the multiply/divide?

Regards,


M.
--
Mark Klein                                 DIS International, Ltd.
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