[PATCH 8/9] shrink-wrap: shrink-wrapping for separate concerns

[Bernd Schmidt]

On 07/19/2016 04:46 PM, Segher Boessenkool wrote:

> But you need the profile to make even reasonably good decisions.

I'm not worried about making cost decisions: as far as I'm concerned 
it's perfectly fine for that. I'm worried about correctness - you can't 
validly save registers inside a loop. So IMO there needs to be an 
additional cfg-based check that verifies whether the bb where we want to 
place parts of the prologue is guaranteed to be executed at most once.


Bernd