From c9e93168073f45d0d2ca8cce8008116ef6b1a86a Mon Sep 17 00:00:00 2001 From: Tom de Vries Date: Tue, 27 Sep 2011 16:10:42 +0000 Subject: re PR middle-end/43864 (Same basic blocks should be merged) 2011-09-27 Tom de Vries PR middle-end/43864 * tree-ssa-tail-merge.c: New file. (struct same_succ_def): Define. (same_succ, const_same_succ): New typedef. (struct bb_cluster_def): Define. (bb_cluster, const_bb_cluster): New typedef. (struct aux_bb_info): Define. (BB_SIZE, BB_SAME_SUCC, BB_CLUSTER, BB_VOP_AT_EXIT): Define. (gvn_uses_equal): New function. (same_succ_print, same_succ_print_traverse, update_dep_bb) (stmt_update_dep_bb, local_def, same_succ_hash) (inverse_flags, same_succ_equal, same_succ_alloc, same_succ_delete) (same_succ_reset): New function. (same_succ_htab, same_succ_edge_flags) (deleted_bbs, deleted_bb_preds): New var. (debug_same_succ): New function. (worklist): New var. (print_worklist, add_to_worklist, find_same_succ_bb, find_same_succ) (init_worklist, delete_worklist, delete_basic_block_same_succ) (same_succ_flush_bbs, purge_bbs, update_worklist): New function. (print_cluster, debug_cluster, update_rep_bb) (add_bb_to_cluster, new_cluster, delete_cluster): New function. (all_clusters): New var. (alloc_cluster_vectors, reset_cluster_vectors, delete_cluster_vectors) (merge_clusters, set_cluster): New function. (gimple_equal_p, gsi_advance_bw_nondebug_nonlocal, find_duplicate) (same_phi_alternatives_1, same_phi_alternatives, bb_has_non_vop_phi) (deps_ok_for_redirect_from_bb_to_bb, deps_ok_for_redirect) (find_clusters_1, find_clusters): New function. (update_vuses, vop_phi, vop_at_entry, replace_block_by): New function. (update_bbs): New var. (apply_clusters): New function. (update_debug_stmt, update_debug_stmts): New function. (tail_merge_optimize): New function. tree-pass.h (tail_merge_optimize): Declare. * tree-ssa-pre.c (execute_pre): Use tail_merge_optimize. * Makefile.in (OBJS-common): Add tree-ssa-tail-merge.o. (tree-ssa-tail-merge.o): New rule. * opts.c (default_options_table): Set OPT_ftree_tail_merge by default at OPT_LEVELS_2_PLUS. * tree-ssa-sccvn.c (vn_valueize): Move to ... * tree-ssa-sccvn.h (vn_valueize): Here. * timevar.def (TV_TREE_TAIL_MERGE): New timevar. * common.opt (ftree-tail-merge): New switch. * params.def (PARAM_MAX_TAIL_MERGE_COMPARISONS) (PARAM_MAX_TAIL_MERGE_ITERATIONS): New parameter. * doc/invoke.texi (Optimization Options, -O2): Add -ftree-tail-merge. (-ftree-tail-merge, max-tail-merge-comparisons) (max-tail-merge-iterations): New item. From-SVN: r179275 --- gcc/tree-ssa-pre.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) (limited to 'gcc/tree-ssa-pre.c') diff --git a/gcc/tree-ssa-pre.c b/gcc/tree-ssa-pre.c index 5c112c0..a7f6cee 100644 --- a/gcc/tree-ssa-pre.c +++ b/gcc/tree-ssa-pre.c @@ -4915,7 +4915,6 @@ execute_pre (bool do_fre) statistics_counter_event (cfun, "Constified", pre_stats.constified); clear_expression_ids (); - free_scc_vn (); if (!do_fre) { remove_dead_inserted_code (); @@ -4925,6 +4924,17 @@ execute_pre (bool do_fre) scev_finalize (); fini_pre (do_fre); + if (!do_fre) + /* TODO: tail_merge_optimize may merge all predecessors of a block, in which + case we can merge the block with the remaining predecessor of the block. + It should either: + - call merge_blocks after each tail merge iteration + - call merge_blocks after all tail merge iterations + - mark TODO_cleanup_cfg when necessary + - share the cfg cleanup with fini_pre. */ + todo |= tail_merge_optimize (todo); + free_scc_vn (); + return todo; } -- cgit v1.1