[llvm] [MIPS][ISel] Fix musttail (PR #161860)

[Djordje Todorovic via llvm-commits]

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djtodoro wrote:

Hi @efriedma-quic.

>hasLocalLinkage overlaps with some of the other checks here.

I agree, will address it.

>Where does this list of checks come from? What are we trying to avoid here? I don't see any obvious reason why you can't tail-call an external function. If there is an issue, there should be a testcase with an explanation.

The problem caused it was around $gp register. In PIC mode, calling external functions via tail call can cause issues with $gp register handling: https://reviews.llvm.org/D24763


https://github.com/llvm/llvm-project/pull/161860