[PATCH] D75801: [InstCombine] Remove known bits constant folding (WIP)

[Johannes Doerfert via Phabricator via llvm-commits]

jdoerfert added inline comments.


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Comment at: test/Transforms/InstCombine/assume.ll:340
+; CHECK-NEXT:    tail call void @llvm.assume(i1 [[CMP2]])
+; CHECK-NEXT:    ret i32 0
 ;
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nikic wrote:
> I'm not sure we really need to do anything about this, I think it's only important that we have an assume(false) here, and SimplifyCFG will deal with the rest.
> 
> If we do want to improve on this, we could convert assume(false) into store undef (the InstCombine UB pattern) and then remove all instructions after store undef.
Can't we replace the UB instruction with unreachable?


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  https://reviews.llvm.org/D75801/new/

https://reviews.llvm.org/D75801