[PATCH, rtl-optimization]: Fix PR 51821, 64bit > 32bit conversion produces incorrect results with optimizations

Paolo Bonzini bonzini@gnu.org
Fri Jan 13 10:51:00 GMT 2012


On 01/13/2012 10:58 AM, Richard Sandiford wrote:
> >  Yes, because new test ALWAYS includes the registers that were wrongly
> >  marked as dead by previous test due to REG_UNUSED and noclobber
> >  processing.
>
> Or to put it another way: the insn-to-insn changes in the current liveness
> sets are all produced by df_simulate_one_insn_{backwards,forwards}, which
> uses the same information.  So I don't think there's any reason why we
> need to keep the current code as well.

Yes, both explanations are sound.  I think the patch is good, too.

Paolo



More information about the Gcc-patches mailing list