mmx register moves through memory

Vahur Sinijärv vahur.sinijarv@cydonia.ee
Wed Aug 31 17:16:00 GMT 2005


Hi,

No, the problem I wrote about is not fixed. I used GCC from CVS head
30.08.2005.
I think you found a different bug, you seem to have many unneccessary
uses of secondary memory between moves from MMX reg to MMX reg. The code
I wrote about (in i386.c) allows direct moves between MMX regs, but
prevents moves directly from general registers to MMX registers, so this
cannot be the case.

Regards,
Vahur

Prakash Punnoor wrote:

>Hi,
>
>Vahur Sinijärv schrieb:
>  
>
>>I've found that latest GCC versions (past 4.0.0 and up to latest in CVS
>>head) never use 'movd %genreg, %mmxreg' to load mmx registers and always
>>insists doing it through memory eq.
>>'mov %genreg, (mem)'
>>'movd (mem), %mmxreg'
>>    
>>
>
>I haven't read entirely through your mail, but I have reported above issue
>already and it seems to be fixed in cvs:
>
>http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23630
>
>Cheers,
>
>  
>




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