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Re: [PATCH 3/3] Speed up genattrtab

Hi,

On Fri, 4 Dec 2009, Segher Boessenkool wrote:

> write_attr_set: Don't update known_true based on previous cases.
> 
> Updating it is very costly.  Not updating it does not result in many
> changes in the generated code.

It does for some targets, and worse ...

> Also, GCC should be able to do (most of) this optimisation by itself,

... this isn't the case very often.  You'd better check compile times for 
some large routines on several architectures to be sure not to introduce 
compile time regressions for improving bootstrap times.


Ciao,
Michael.
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