[PATCH] D11662: Filter cold blocks off the loop chain when profile data is available.

[Daniel Jasper via llvm-commits]

djasper added a comment.

Why only do this if profile data is available? Are we scared that the statically derived probabilities are off by too much?

How does this affect nested loops? Is the 'outlined' block still in the outer loop? I am not sure which one would be better, but maybe we should add a comment and a test to document the behavior?

Should there be some minimum size for the block to be outlined? A very short block will still increase branch count, but not really affect cache locality. For those, the trade-off might be different.


http://reviews.llvm.org/D11662