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Date: Tue, 27 Mar 2012 06:48:14 +0200
From: Andris Pavenis <andris DOT pavenis AT iki DOT fi>
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To: djgpp AT delorie DOT com
Subject: Re: CC1.EXE/GCC.EXE crashes with SIGILL, hard.
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Reply-To: djgpp AT delorie DOT com

On 03/27/2012 02:02 AM, Rugxulo wrote:
> Hi,
>
> On Mar 20, 9:18 am, RayeR<gl DOT  DOT  DOT  AT centrum DOT cz>  wrote:
>>
>> Does the testcase generate cmove even without
>> __attribute__((__target__("sse"))) ?
>
> No, I don't think it would help, though I haven't tried again since my
> previous attempt.

The idea is to use detect CPU on which GCC is running and to
use best suited code for actual CPU. Who would care that there is
some CMOVE instructions in procedure which whould not even be
executed. Therefore my inititial approach with objdump --disassemble
was not correct

The same approach is also used in DJGPP port of GMP (configure
option --enable-fat). GMP is also used by GCC, so it would be
not too surprising to also see instructions not available to
i586 there.

Unfortunate the real problem seems to be that GCC perhaps
misdetects available features and tries to use code not suitable
for i586

One could try to extract related code separately and run tests
on different CPUs. I only have Core2 so I do not have
systems on which to do the tests

Andris