[PATCH] D116322: [Analysis] allow caller to choose signed/unsigned when computing constant range

[Sanjay Patel via Phabricator via llvm-commits]

spatel created this revision.
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We should not lose analysis precision if an 'add' has both no-wrap flags (nsw and nuw) compared to just one or the other.

This patch is modeled on a similar construct that was added with D59386 <https://reviews.llvm.org/D59386>.

I don't think it is possible to expose a problem with an unsigned compare because of the way this was coded (nuw is handled first).

InstCombine has an assert that fires with the example from:
https://github.com/llvm/llvm-project/issues/52884
...because it was expecting InstSimplify to handle this kind of pattern with an smax.


https://reviews.llvm.org/D116322

Files:
  llvm/include/llvm/Analysis/ValueTracking.h
  llvm/lib/Analysis/BasicAliasAnalysis.cpp
  llvm/lib/Analysis/InstructionSimplify.cpp
  llvm/lib/Analysis/ValueTracking.cpp
  llvm/lib/Transforms/Vectorize/VectorCombine.cpp
  llvm/test/Transforms/InstCombine/minmax-intrinsics.ll
  llvm/test/Transforms/InstSimplify/icmp-constant.ll
  llvm/unittests/Analysis/ValueTrackingTest.cpp

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