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Re: optimisation question
Robert Dewar <dewar@adacore.com> writes:
>
> Even in more difficult cases, people who mess with code at the C source
> level in an attempt to do improve ILP often make things worse by trying
> to second guess the compiler. ILP is really the domain of the compiler
> or of a (fairly heroic) human assembly language writer.
There are common cases where this definitely isn't true. For example
inserting explicit prefetches for pointer chasing or changing some
algorithms to use SSE2/Altivec/etc. builtins and become SIMD. While
some of this stuff might be done by a compiler at some point for the
better optimization you still need a human.
-Andi