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author | Richard Guenther <rguenther@suse.de> | 2009-05-08 12:24:22 +0000 |
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committer | Richard Biener <rguenth@gcc.gnu.org> | 2009-05-08 12:24:22 +0000 |
commit | 788d3075c55a723d1c266938c3ae66aeee70afb4 (patch) | |
tree | aabbf2fc3c6814aff869e013b040c9d31041d85e /gcc/tree-scalar-evolution.c | |
parent | 00952e9784e41f1ee7a1e4384904a5fd42f610a6 (diff) | |
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re PR tree-optimization/40062 (high memory usage and compile time in SCEV cprop with -O3)
2009-05-08 Richard Guenther <rguenther@suse.de>
PR tree-optimization/40062
* tree-scalar-evolution.c (follow_ssa_edge_in_condition_phi):
Avoid exponential behavior.
From-SVN: r147283
Diffstat (limited to 'gcc/tree-scalar-evolution.c')
-rw-r--r-- | gcc/tree-scalar-evolution.c | 8 |
1 files changed, 3 insertions, 5 deletions
diff --git a/gcc/tree-scalar-evolution.c b/gcc/tree-scalar-evolution.c index 2d31f9f..b3990c6 100644 --- a/gcc/tree-scalar-evolution.c +++ b/gcc/tree-scalar-evolution.c @@ -1319,11 +1319,7 @@ follow_ssa_edge_in_condition_phi (struct loop *loop, *evolution_of_loop = evolution_of_branch; - /* If the phi node is just a copy, do not increase the limit. */ n = gimple_phi_num_args (condition_phi); - if (n > 1) - limit++; - for (i = 1; i < n; i++) { /* Quickly give up when the evolution of one of the branches is @@ -1331,10 +1327,12 @@ follow_ssa_edge_in_condition_phi (struct loop *loop, if (*evolution_of_loop == chrec_dont_know) return t_true; + /* Increase the limit by the PHI argument number to avoid exponential + time and memory complexity. */ res = follow_ssa_edge_in_condition_phi_branch (i, loop, condition_phi, halting_phi, &evolution_of_branch, - init, limit); + init, limit + i); if (res == t_false || res == t_dont_know) return res; |