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Re: poor gcc-4.0 performance

On Thu, 2005-06-16 at 18:37 +0400, Serge Belyshev wrote:
> >bruteforcing, or I am missing something out? Is there a reason for such
> >performance differences?
> Yes, You have used '-O3' flag which triggers -finline-functions
I've tried with -O2 flag before, and had similar results, gcc-4 soars!

> Default inline heuristics just cannot fit well for all, and thus are subject to
> change from time to time. See [1] and [2] for more information on this topic.
> To fix that, You have few choices:
> o use -O2
> o tweak inlining heuristics yourself (see [3])
> o use -fprofile-generate/-fprofile-use, like this:
> $ cd john-1.6.38/src
> $ make CFLAGS='-c -O3 -fprofile-generate' LDFLAGS=-fprofile-generate linux-x86-64
> $ ../run/john --test
> $ make clean
> $ make CFLAGS='-c -O3 -fprofile-use' LDFLAGS=-fprofile-use linux-x86-64

doing the above still gives me similar results as with general

> [1] http://gcc.gnu.org/ml/gcc-patches/2005-03/msg00333.html
> [2] http://gcc.gnu.org/ml/gcc-patches/2005-03/msg01936.html
> [3] http://gcc.gnu.org/onlinedocs/gcc/Optimize-Options.html#index-param-571

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