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Re: IF conversion bug with CC0


On 04/04/2016 03:13 PM, Dan wrote:
Jeff,

Thank you for your quick response!

Yes, I have a custom ISA.  I am building a custom back end.  The
project, in its current state, can be found at:

http://opencores.com/project,zipcpu

Can you tell me whether the difference between CC0 processing and
non-CC0 processing is a GCC difference or a target ISA difference?
It's a difference in how you express condition code handling from your ISA to GCC.

From a 30 second view of your ISA, it appears that most arithmetic/logicals unconditionally set the condition codes.

I would suggest modeling condition code handling similar to how it's done on the x86 port.

jeff


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