[LLVMdev] thumb2 has divide instructions

Bagel bagel99 at gmail.com
Mon Dec 7 11:07:44 PST 2009

Anton Korobeynikov wrote:
> Hello
>> Is this necessary?  Since the absence of the predicate causes lowering to
>> expand divides, the pattern should never show up.
> Just to guard codegen bugs. If anything went wrong (when predicates
> will be used) then you'll get nice assertion "cannot yet select".
>> Agreed.  Now how do we get this done?
> Just look how ArmV7A is defined and do something similar...

It's not clear to me how to add the V7m architecture without breaking 
something.  The predicates that use ARMArchEnum assume an ordering.  And V7m is 
a subset of v7a (and of v6t2).  So a strict ordering scheme starts to break down.

I think I'll just enter this in the bug list and let people who understand the 
subtarget implications do the fix.

regards, bagel

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