[PATCH] D75098: Add TCOPY, a terminator form of the COPY instr

[Quentin Colombet via Phabricator via llvm-commits]

qcolombet requested changes to this revision.
qcolombet added a comment.
This revision now requires changes to proceed.

I don't think introducing the TCOPY opcode is a valid solution.
Let's assume the copy doesn't get coalesced, that means it needs to be executed after the inlineasm branch. And this is not going to happen if it sits in the same basic block right after the jump.

What happens if you put the copy at the beginning of each successor?
You mentioned that this is not possible because the live-ins wouldn't be set, but I would expect that this information would be correctly computed when building the liveness information. I.e., I don't expect this to be a problem.

> we allow a store of a physical register after the INLINEASM_BR when optimizations are disabled.

That sounds wrong.

Could we step back a little bit, what is the semantic of `INLINEASM_BR`?


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https://reviews.llvm.org/D75098