[Bug tree-optimization/97623] [9/10 Regression] Extremely slow O2 compile (>>O(n^2))
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97623 --- Comment #22 from CVS Commits --- The releases/gcc-10 branch has been updated by Richard Biener : https://gcc.gnu.org/g:eddcb627ccfbd97e025cf366cc3f3bad76211785 commit r10-9246-geddcb627ccfbd97e025cf366cc3f3bad76211785 Author: Richard Biener Date: Tue Nov 3 15:03:41 2020 +0100 tree-optimization/97623 - Avoid PRE hoist insertion iteration We are not really interested in PRE opportunities exposed by hoisting but only the other way around. So this moves hoist insertion after PRE iteration finished and removes hoist insertion iteration alltogether. It also guards access to NEW_SETS properly. 2020-11-11 Richard Biener PR tree-optimization/97623 * tree-ssa-pre.c (insert): Move hoist insertion after PRE insertion iteration and do not iterate it. (create_expression_by_pieces): Guard NEW_SETS access. (insert_into_preds_of_block): Likewise. * gcc.dg/tree-ssa/ssa-hoist-3.c: Adjust. * gcc.dg/tree-ssa/ssa-hoist-7.c: Likewise. * gcc.dg/tree-ssa/ssa-pre-30.c: Likewise.
[Bug tree-optimization/97623] [9/10 Regression] Extremely slow O2 compile (>>O(n^2))
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97623 --- Comment #21 from CVS Commits --- The releases/gcc-10 branch has been updated by Richard Biener : https://gcc.gnu.org/g:0fd6247a3014038af349db3a01748b5dc17d87a0 commit r10-9245-g0fd6247a3014038af349db3a01748b5dc17d87a0 Author: Richard Biener Date: Fri Oct 30 13:32:32 2020 +0100 tree-optimization/97623 - avoid excessive insert iteration for hoisting This avoids requiring insert iteration for back-to-back hoisting opportunities as seen in the added testcase. For the PR at hand this halves the number of insert iterations retaining only the hard to avoid PRE / hoist insert back-to-backs. 2020-10-30 Richard Biener PR tree-optimization/97623 * tree-ssa-pre.c (insert): First do hoist insertion in a backward walk. * gcc.dg/tree-ssa/ssa-hoist-7.c: New testcase. (cherry picked from commit 82ff7e3426ea926d090777173977f8bedd086816)
[Bug tree-optimization/97623] [9/10 Regression] Extremely slow O2 compile (>>O(n^2))
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97623 Richard Biener changed: What|Removed |Added Known to work||11.0 Summary|[9/10/11 Regression]|[9/10 Regression] Extremely |Extremely slow O2 compile |slow O2 compile (>>O(n^2)) |(>>O(n^2)) | --- Comment #20 from Richard Biener --- So I think we can say it is fixed for GCC 11.
