On Thu, 17 Jun 2010, Gautier sent:
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|"On Jun 10, 5:48 pm, Colin Paul Gloster <Colin_Paul_Glos...@ACM.org>|
|wrote:                                                              |
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|> Additionally, loop unrolling should be considered.                |
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|Just a note for those who are not aware of and who'd be tempted to  |
|unroll loops by hand: compilers are able to unroll loops themselves.|
|For instance GNAT has a -funroll-loops for a long time (and also -  |
|fpeel-loops and -funswitch-loops)."                                 |
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It is possible to obtain better performance by both manually unrolling
and having a compiler unroll for you at the same, instead of by
relying on just a compiler or just manual unrolling. See for example
"Computer Architecture: A Quantitative Approach" (in which manual
unrolling was called "symbolic loop unrolling").

Sincerely,
Colin Paul Gloster