From b091dc59bfbdb8a9414f2e64f95b1284f991acf5 Mon Sep 17 00:00:00 2001 From: rakdver Date: Thu, 10 Feb 2005 00:32:47 +0000 Subject: PR tree-optimization/18687 * tree-flow.h (find_loop_niter): Declare. * tree-ssa-loop-ivcanon.c (canonicalize_loop_induction_variables): Try using scev even for loops with more than one exit. * tree-ssa-loop-ivopts.c (struct loop_data): Removed niter field. (struct ivopts_data): Added niters field. (struct nfe_cache_elt): New. (nfe_hash, nfe_eq, niter_for_exit, niter_for_single_dom_exit): New functions. (tree_ssa_iv_optimize_init): Initialize niters cache. (determine_number_of_iterations): Removed. (find_induction_variables): Do not call determine_number_of_iterations. Access niters for single exit through niter_for_single_dom_exit. (add_iv_outer_candidates): Access niters for single exit through niter_for_single_dom_exit. (may_eliminate_iv): Take data argument. Use niter_for_exit. Do not use number_of_iterations_cond. (iv_period): New function. (determine_use_iv_cost_condition): Pass data to may_eliminate_iv. (may_replace_final_value): Take data argument. Use niter_for_single_dom_exit. (determine_use_iv_cost_outer): Pass data to may_replace_final_value. (rewrite_use_compare): Pass data to may_eliminate_iv. (rewrite_use_outer): Pass data to may_replace_final_value. (free_loop_data): Clean up the niters cache. (tree_ssa_iv_optimize_finalize): Free the niters cache. (tree_ssa_iv_optimize_loop): Do not call loop_commit_inserts. * tree-ssa-loop-niter.c (find_loop_niter): New function. (find_loop_niter_by_eval): Use tree_int_cst_lt. (num_ending_zeros): Moved to tree.c. * tree.h (num_ending_zeros): Declare. * tree.c (num_ending_zeros): Moved from tree.c. git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@94787 138bc75d-0d04-0410-961f-82ee72b054a4 --- gcc/tree-ssa-loop-ivcanon.c | 23 +++++++++++++++++------ 1 file changed, 17 insertions(+), 6 deletions(-) (limited to 'gcc/tree-ssa-loop-ivcanon.c') diff --git a/gcc/tree-ssa-loop-ivcanon.c b/gcc/tree-ssa-loop-ivcanon.c index 4635a023962..a2930166908 100644 --- a/gcc/tree-ssa-loop-ivcanon.c +++ b/gcc/tree-ssa-loop-ivcanon.c @@ -220,12 +220,23 @@ canonicalize_loop_induction_variables (struct loops *loops, struct loop *loop, niter = fold (build2 (MINUS_EXPR, TREE_TYPE (niter), niter, build_int_cst (TREE_TYPE (niter), 1))); } - else if (try_eval) - niter = find_loop_niter_by_eval (loop, &exit); - - if (chrec_contains_undetermined (niter) - || TREE_CODE (niter) != INTEGER_CST) - return false; + else + { + /* If the loop has more than one exit, try checking all of them + for # of iterations determinable through scev. */ + if (!loop->single_exit) + niter = find_loop_niter (loop, &exit); + + /* Finally if everything else fails, try brute force evaluation. */ + if (try_eval + && (chrec_contains_undetermined (niter) + || TREE_CODE (niter) != INTEGER_CST)) + niter = find_loop_niter_by_eval (loop, &exit); + + if (chrec_contains_undetermined (niter) + || TREE_CODE (niter) != INTEGER_CST) + return false; + } if (dump_file && (dump_flags & TDF_DETAILS)) { -- cgit v1.2.1