[PATCH] D26083: [LV] Scalarize operands of predicated instructions

[Matthew Simpson via llvm-commits]

mssimpso added a comment.

Michael/Gil,

I'm wrapping up addressing your comments, but I have a question about testing. Since this change is cost-model driven, all tests should really live under a target-specific directory (i.e., test/Transforms/LoopVectorize/AArch64). That's easy enough to do, but what should we do about all the target-independent tests that currently exist in the top-level directory? With this change, we would be introducing target-specific behavior that may change how those tests are vectorized, depending on the default target.

I can think of two ways to avoid this: (1) disable scalarization when a user-specified vectorization factor is provided. That is, only perform the optimization when the cost model is actually run. Or (2) introduce a new flag (e.g., --enable-scalarization-with-predication), defaulting to true that we could then disable in the run line of all the current top-level tests.

What do you think?


https://reviews.llvm.org/D26083