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Re: [tree-ssa] 20% compile time regression vs. 3.4
Richard Guenther wrote:
I thought it was time for another 3.4 vs. tree-ssa compile-time
comparison. For -O2 compile-time we regressed quite a bit (20%) with the
main problem areas are (first 3.4, second tree-ssa):
garbage collection : 12.19 ( 7%) usr 0.00 ( 0%) sys 12.50 ( 7%) wall
garbage collection : 17.26 ( 8%) usr 0.02 ( 0%) sys 17.45 ( 8%) wall
tree-ssa uses about double amount of memory
Tree-ssa expression nodes point to a separately-allocated location_t
object. It does try to share these, but it will to extra gc time, if
nothing else.
I could try to dust off my "replace location_t by source_location"
patch. I don't know if it would be appropriate for the current stage
of tree-ssa "semi-freeze", though it helps with compile speed (no
guarantee that it does), maybe I should try it.
--
--Per Bothner
per@bothner.com http://per.bothner.com/