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Re: Combine four insns


Bernd Schmidt wrote:

On 08/07/2010 10:10 AM, Eric Botcazou wrote:

Combining Steven and Bernd's figures, 1% of a bootstrap time is 37% of the combiner's time. The result is 0.18% more combined insns. It seems to me that we are already very far in the directory of diminishing returns.

Better to look at actual code generation results IMO. Do you have an opinion on the examples I included with the patch?

Well, one of the limitations of this analysis is that it is static - it doesn't say what the run-time influence of the simplification is.


In case it is inside a heavily used loop, it might be far more important than it at first looks ...

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