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Re: [PATCH] Do not provide inlines for GCC build-in functions


On Fri, May 18, 2012 at 3:06 AM, Andreas Jaeger <aj@suse.de> wrote:
>> I find it a bit lame that we go from a math inline to a builtin behind
>> the users back, but this seems to be common practice, and I don't see
>> a better solution.
>
> As Uros commented in gcc.gnu.org/bugzilla/show_bug.cgi?id=53190 "As a side
> note, mathinline.h really needs some serious TLC, there are many
> functions that are much better implemented with gcc builtin functions, not
> to
> mention that x87 asm in 32bit case interferes *badly* with -mfpmath=sse.
> "
>
> GCC can do a better job optimization the call if a builtin exists, so let's
> use it.

I don't disagree that GCC can do a better job.

However, you've just changed the conditions under the code in question
is selected and this could result in unexpected behaviour for the user
even though their flags have remained consistent.

I understand why we do it though, it just doesn't make me that happy :-/

Cheers,
Carlos.


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