[Bug tree-optimization/64193] [4.8/4.9/5 Regression] Decreased performance after r173250

[rguenther at suse dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64193

--- Comment #8 from rguenther at suse dot de <rguenther at suse dot de> ---
On Tue, 9 Dec 2014, dominiq at lps dot ens.fr wrote:

> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64193
> 
> --- Comment #7 from Dominique d'Humieres <dominiq at lps dot ens.fr> ---
> AFAICT if there is any speedup with the patch in comment 5, it is negligible on
> a 2.8Ghz Corei7 and x86_64-apple-darwin14: ~7.1s with/without the patch. Note
> that the timing in the test is not very precise.

As said the patch is more interesting on the 4.9 branch where the DOM
improvements do not mitigate its effect (or with -fno-tree-dominator-opts)