[PATCH] D33433: [SCEV] Select between two equal values

[Sanjoy Das via Phabricator via llvm-commits]

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I'm not convinced SCEV is the best place to handle this -- by the time IR hits SCEV `select A, B, B` should already have been simplified to `B`.  We do not handle "simple" patterns like `br (xor C, true), label A, label B` for the same reason.

If you *must* do this (and I'm not yet convinced that we must), I'd instead call `SimplifyInstruction` at a higher level (at `createSCEV` perhaps).


https://reviews.llvm.org/D33433