PATCH: PR target/40470: unable to find a register to spill in class ‘SSE_FIRST_REG’

Richard Earnshaw rearnsha@arm.com
Thu Jun 18 14:26:00 GMT 2009


On Thu, 2009-06-18 at 12:44 +0200, Richard Guenther wrote:

> > So my proposed solution would be: Do not allow combine to propagate
> > SETany _SRC that contains hard regs.
> 
> At least not if that increases the number of uses of the hard reg.
> If we can distinguish that case properly.

Combine will only do the propagation if the original register is dies in
the combination.  So the only situation where the liveness could
increase is if combine uses that register twice (or more) in the
'simplified' result.

R.



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