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Re: LRA reload produces invalid insn
> On Nov 2, 2018, at 9:34 AM, Peter Bergner <bergner@linux.ibm.com> wrote:
>
> On 11/1/18 10:37 PM, Vladimir Makarov wrote:
>> On 11/01/2018 08:25 PM, Paul Koning wrote:
>>> Is this an LRA bug, or is there something I need to do in the target to prevent this happening?
>> It is hard to say whose code is responsible for this. It might be a wrong machine-dependent code or a LRA bug.
>>
>> Paul, could you send me full LRA dump file (.reload). It might help me to say more specific reason for the bug. LRA has iterated sub-passes and the full dump can say where LRA started to behave wrongly.
>>
>
> I'll note that when we ported the rs6000 (ie, ppc*) port over to LRA
> from reload, we hit many target problems. It seems LRA is much less
> forgiving to bad constraints, predicates, etc. than reload was.
> I think that's actually a good thing.
>
> Peter
Yes, I ran into that, and Segher (I think) helped me with a bad predicate case. It doesn't help that the documentation isn't all that explicit about what the requirements are.
paul