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Re: PPro patch #3


> 
> 
>   In message <m0yhbje-000268C@ocean.lucon.org>you write:
>   > Here is a patch to fix unordered comparison for PPro.
>   > 
>   > 
>   > H.J.
>   > ----
>   > Tue May 19 06:51:19 1998  H.J. Lu  (hjl@gnu.org)
>   > 
>   > 	* config/i386/i386.c (notice_update_cc, output_float_compare):
>   > 	Enable TARGET_CMOVE support.
>   > 
>   > Mon May 11 08:04:17 1998  H.J. Lu  (hjl@gnu.org)
>   > 
>   > 	* config/i386/i386.c (output_float_compare): Fix the unordered
>   > 	comparison for IEEE math and CC_FCOMI.
> Exactly what problem is this patch trying to fix?

The testcase is in my previous email. But you need to enable CC_FCOMI
to see it.

> 
> "Here is a patch to fix unordered comparison for PPro." tells me
> almost nothing.
> 

Please get PPro/II reference manual and check out fcomi. You will see
PPro/II cannot handle unordered comparison directly which sets CC in a
way compatible with integer comparison. BTW, Jim may know it since it
is he who disabled fcomi, which hides the bug.



-- 
H.J. Lu (hjl@gnu.org)


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