[PATCH] D13529: [Polly] Allow alloca instructions in the SCoP

[Tobias Grosser via llvm-commits]

grosser added a comment.

I am also surprised 'alloc' is not different to any other instruction.

We can possibly support it in some way, but this requires some additional thoughts similar to what Michael suggested. Will the varying base pointer cause troubles, .../. Can you dead-code-eliminate allocs? Can you reorder allocs?

Do you actually have a use case that produces such kind of code and that makes it worth to support this case? As deadalnix pointed out, allocas outside of the entry block have a lot of surprising behaviors (and are e.g. not even considered by mem2reg for good reasons).

Best,
Tobias


http://reviews.llvm.org/D13529