[PATCH] D17936: [LICM] Don't silently ignore constant expressions in promoteLoopAccessesToScalars()

[Michael Kuperstein via llvm-commits]

mkuper added a comment.

Thanks for looking at it, Philip and Sanjoy.

For the test case, there's a single value in the alias set:

  Alias Set Tracker: 1 alias sets for 1 pointer values.
    AliasSet[0xa0b5d8, 1] must alias, Mod       Pointers: (i32* getelementptr inbounds ([4 x i32], [4 x i32]* @v, i32 0, i32 1), 12)

The constant expr that seems to confuse LCIM isn't the GEP, it's the bitcast.
Actually, it's possible the GEP is just noise. I'd expect the same to happen when directly bitcasting from @v. I'll check, and simplify the test if that's the case.


http://reviews.llvm.org/D17936