[Gllug] code optimisations

[Rich Walker]

Chris Ball <chris at void.printf.net> writes:

[snip useful bit]
>
>> But it's ... interesting ... to communicate to a C compiler that the
>> second optimisation is valid. If you did:
>
> Quite.  The compiler can't always know that there's no data dependency 
> inside the loop.  The current plan for autovect-branch is to control 
> the vectorizer with a #pragma (which is apparently how icc does it).

I thought there was a preference not to use #pragma ("it's irredeemably
broken")? Or has this changed?

cheers, Rich.

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