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Re: conflicts between combine and pre global passes?


On Sat, Apr 28, 2012 at 5:15 PM, Eric Botcazou <ebotcazou@adacore.com> wrote:
>> I am sorry for misleading description. By "propagate register 172 in
>> insn79 and delete insn78"
>> I was meaning that gcc replaces reg 172 in insn79 with another
>> register contains ZERO and
>> that register(saying reg X) is defined in other basic blocks.
>
> OK, in this case I think you need to find out why no local pass before the
> problematic global pass does the obvious constant propagation into insn 79.
>
Yes, the reason here should be the pattern for insn 79 has predicates on
its operands and does not allow constant here.

Thanks

-- 
Best Regards.


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