[FFmpeg-devel] [PATCH] fix compiling VIS assembly on SPARC

Derek E. Lewis dlewis
Sun Sep 16 07:14:01 CEST 2007


On Fri, 14 Sep 2007, Balatoni Denes wrote:

> Thanks Derek, that did clear things up for me - because I had no idea what
> these obsolote v8plus registers were.

Actually, part of what I said was wrong, but the concept is still the 
same: by default, GCC (as of 3.x) builds for SPARCv8. 'v8plus' is simply 
32-bit code, but uses extra registers that SPARCv9 provides over SPARCv8. 
This means a binary built for 'v8plus' requires an UltraSPARC or another 
SPARCv9-compatible system to execute. It looks like GCC as of version 4.x 
defaults to 'v8plus'. I think it was gcc-2.x that built for SPARCv7 by 
default. It is probably to our advantage not to assume what architecture 
gcc will default to when compiling, and to define some level of SPARC 
compliance we expect. A reasonable level would by SPARCv8, IMO, as there 
are still some users out there using sun4m systems, which are SPARCv8. Of 
course, this has no relevance on your inline VIS code.

> So this should be fixed by the (already applied) Makefile patch, right?

Yes, I think so, but do not quote me on that, as I have not tested it. :-)

Derek E. Lewis
dlewis at solnetworks.net
http://delewis.blogspot.com





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