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Re: GCC beaten by ICC in stupid trig test!


On Mon, 15 Mar 2004, Paolo Carlini wrote:

> Now, I have another question: when -ffast-math is passed, should we even 
> collapse
> the loop to a single integer to be multiplied by the return value of doit?

I don't know whether this will occur in real code (and so whether it is
worth doing), but replacing repeated addition with multiplication seems
like the sort of thing -ffast-math can do.  (The default for the
FP_CONTRACT pragma is implementation-defined, but that would only allow
contraction within a single expression, e.g. x+x+x+x --> 4*x, not in loops
like this.)

-- 
Joseph S. Myers
jsm@polyomino.org.uk


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