[PATCH] D47891: [InstSimplify] shl nuw %x, %y -> %x iff KnownBits says %x is negative.

[Roman Lebedev via Phabricator via llvm-commits]

lebedev.ri abandoned this revision.
lebedev.ri added a comment.

Ok, got the self-hosting stats.

  $ find -iname *.stats | wc -l
  3049
  $ find -iname *.stats | xargs grep NumShlNuwNonConstF
  ./lib/Analysis/CMakeFiles/LLVMAnalysis.dir/LoopInfo.stats:      "instsimplify.NumShlNuwNonConstFolded": 1,
  ./unittests/ADT/CMakeFiles/ADTTests.dir/PriorityWorklistTest.stats:     "instsimplify.NumShlNuwNonConstFolded": 1,

So counter2, times the fold happened is `2`.

I haven't found where is the tooling to process these `.stats` dumps, so i have manually processed it for the `"instsimplify.NumShlNuwNonConst"` entries.
The counter1, the times we called `computeKnownBits()` here is `643566`.

I'm guessing it means we don't want this :)


Repository:
  rL LLVM

https://reviews.llvm.org/D47891