[Bug other/64928] Inordinate cpu time and memory usage in "phase opt and generate" with -ftest-coverage -fprofile-arcs

[lucier at math dot purdue.edu]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64928

--- Comment #4 from lucier at math dot purdue.edu ---
On 02/03/2015 04:32 PM, pinskia at gcc dot gnu.org wrote:
> > --- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
> Note phase opt and generate is a toplevel time area.
> The passes which take most of the time are:

I'm also concerned about excessive memory usage; the largest passes (> 
20 MB) are

  alias analysis          :   0.21 ( 1%) usr   0.00 ( 0%) sys   0.19 ( 
1%) wall   23934 kB ( 5%) ggc
  tree SSA incremental    :   0.23 ( 1%) usr   0.01 ( 1%) sys   0.26 ( 
1%) wall   27481 kB ( 5%) ggc
  dominator optimization  :   0.22 ( 1%) usr   0.01 ( 1%) sys   0.22 ( 
1%) wall   27417 kB ( 5%) ggc
  tree loop invariant motion:   0.16 ( 0%) usr   0.03 ( 4%) sys   0.19 ( 
1%) wall   64219 kB (12%) ggc
  expand                  :   0.39 ( 1%) usr   0.02 ( 2%) sys   0.40 ( 
1%) wall   87038 kB (17%) ggc
  CSE                     :   7.53 (21%) usr   0.01 ( 1%) sys   7.53 
(20%) wall   30934 kB ( 6%) ggc
  integrated RA           :   0.87 ( 2%) usr   0.00 ( 0%) sys   0.99 ( 
3%) wall   48097 kB ( 9%) ggc
  LRA non-specific        :   1.61 ( 4%) usr   0.01 ( 1%) sys   1.63 ( 
4%) wall   37254 kB ( 7%) ggc

This also affects the 4.8 branch and the mainline.