[PATCH] D69183: [CVP] When proving that @llvm.with.overflow()/@llvm.sat() don't overflow, also try to prove other no-wrap

[Roman Lebedev via Phabricator via llvm-commits]

lebedev.ri created this revision.
lebedev.ri added reviewers: nikic, spatel, reames.
lebedev.ri added a project: LLVM.
Herald added a subscriber: hiraditya.
lebedev.ri updated this revision to Diff 225660.
lebedev.ri added a comment.

Typos


CVP, unlike InstCombine, does not run till exaustion.
It only does a single pass.

When dealing with those special binops, if we prove that they can
safely be demoted into their usual binop form,
we do set the no-wrap we deduced. But when dealing with usual binops,
we try to deduce both no-wraps.

So if we convert e.g. @llvm.uadd.with.overflow() to `add nuw`,
we won't attempt to check whether it can be `add nuw nsw`.

This patch proposes to call `processBinOp()` on newly-created binop.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D69183

Files:
  llvm/lib/Transforms/Scalar/CorrelatedValuePropagation.cpp
  llvm/test/Transforms/CorrelatedValuePropagation/overflows.ll

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