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Re: Miscompilation of remainder expressions


Gabriel Dos Reis <gdr@cs.tamu.edu> writes:

> Ian, do you believe something along the line of
> 
>  # > I mean, could not we generate the following for "%": 
>  # >
>  # >     rem a b := 
>  # >       if abs(b) == 1
>  # >          return 0
>  # >       return <machine-instruction> a b
>  #
>  # On x86 processors that have conditional moves, why not do the equivalent
>  # of
>  #
>  #         neg_b = -b;
>  #         cmov(last result is negative,neg_b,b)
>  #         __machine_rem(a,b)
>  #
>  # Then there's no disruption of the pipeline.
> 
> is workable for the affected targets?

Sure, I think the only real issue is where the code should be
inserted.

Ian


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