[Bug tree-optimization/35639] [4.3/4.4 Regression] -fprofile-generate + PRE = big compile-time

[bonzini at gnu dot org]

------- Comment #8 from bonzini at gnu dot org  2008-11-22 16:00 -------
The problem was that without -fprofile-generate the time spent there was
basically zero.  Since the profiling code is building a MST of the control-flow
graph, it should produce absolutely no PRE opportunity and it's a pity that it
causes such a slowdown.

I wonder if there is some low-hanging fruit to eliminate value numbers that
cannot be redundant.


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35639