[PATCH] D87149: [InstCombine] erase instructions leading up to unreachable

[Sanjay Patel via Phabricator via llvm-commits]

spatel added a comment.

In D87149#2282328 <https://reviews.llvm.org/D87149#2282328>, @spatel wrote:

> I guess we could try to eliminate phi operands if an incoming block (g.exit) is unreachable? But simplifycfg should do that already, so I don't know if we want instcombine trying to do that too.

Actually, that would be out-of-bounds for instcombine. Removing a phi operand would mean removing the incoming block too, and we don't do that in instcombine. So I think we just bail out if a value still has uses. SimplifyCFG will eventually get it.


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