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Re: [patch i386]: Sibcall tail-call improvement and partial fix PR/60104


Hello,

Does this touch or address the problem raised in
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=46219#c3 ?

[Uros Bizjak]
>> For some reason, memory operand is prohibited in a sibcall, see
>> predicates.md [...]

[Richard Henderson]
> That would be because we have no good way to say: global memory is fine, but
> the on-stack memory that we just deallocated is not.

> In addition for this case, we have to ensure that the registers used to do
> the indexing are still valid after call-saved registers have been restored,
> and avoid any call-clobbered registers that might be needed to execute the
> epilogue.

> In general I don't think this is solvable, but for this specific case we
> could add a peephole.


Thanks.
Alexander


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