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Re: PATCH: PR target/40838: gcc shouldn't assume that the stack is aligned


"H.J. Lu" <hjl.tools@gmail.com> writes:

>> If somebody asked you "where does gcc set the required stack
>> alignment?" would you expect the answer to be "in the vectorizer
>> code?"
>
> Yes, vectorizer may put requirement on stack alignment. But it is up
> to backend to decide and it isn't the only place gcc may require
> certain stack alignment.

It's the only place your patch changes.


>> Is there any way we can fix incoming stack alignment so that it can be
>> controlled by automatic stack variables? ÂI don't understand why this
>
> The incoming stack alignment can be controlled by automatic stack
> variables. But it can't be controlled by pseudo registers.
>
>> is not done by the prologue and epilogue code.
>>
>
> Because the prologue and epilogue code is generated after
> RTL expansion starts?

That just restates my question without answering it.

Ian


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