From 7636e8782aa0dac322c22631c4cd0b60c0eb1842 Mon Sep 17 00:00:00 2001 From: Zinin Ivan WX1305386 Date: Tue, 3 Dec 2024 16:02:15 +0300 Subject: [PATCH] Fix bugs Added check if then_bb got single succ in process_complex_cond() Made processing of cases when then_bb is pred of EXIT and got return statement inside. Splitting of edge from EXIT pred to EXIT deletes return statement, and duplication of then_bb will got no return statement too. So in such cases we need to build return statement in merge_bb by ourselves. --- gcc/gimple-if-split.cc | 35 +++++++++++++++++++++++++++++++++-- 1 file changed, 33 insertions(+), 2 deletions(-) diff --git a/gcc/gimple-if-split.cc b/gcc/gimple-if-split.cc index 3446204ea..351515435 100644 --- a/gcc/gimple-if-split.cc +++ b/gcc/gimple-if-split.cc @@ -38,6 +38,7 @@ along with GCC; see the file COPYING3. If not see #include "tree-cfg.h" #include "bitmap.h" #include "cfganal.h" +#include "cfgloop.h" /* Perform splitting if-then-else patterns, whose complex OR condition in cond-bb contains comparison of some variable with constant and then-bb got @@ -255,6 +256,7 @@ process_complex_cond (basic_block cond_bb, basic_block then_bb, cond_parts_defs defs; if (!can_duplicate_block_p (then_bb) + || !single_succ_p (then_bb) || !necessary_complex_cond_p (cond, then_bb, &defs)) return; @@ -345,14 +347,39 @@ static basic_block make_two_separate_calls (basic_block outer_cond_bb, basic_block inner_cond_bb, basic_block then_bb) { - if (!can_duplicate_block_p (then_bb) || EDGE_COUNT (then_bb->succs) != 1) + if (!can_duplicate_block_p (then_bb) || !single_succ_p (then_bb)) return NULL; edge outer_then_e = find_edge (outer_cond_bb, then_bb); /* Making duplication of then_bb. */ basic_block then_bb_dom = get_immediate_dominator (CDI_DOMINATORS, then_bb); + + /* Saving ret_value and then_bb succ edge flags, if then_bb is pred of + * EXIT_BLOCK and has return statement inside. */ + tree ret_val; + int then_bb_succ_edge_flags; + if (single_succ (then_bb) == EXIT_BLOCK_PTR_FOR_FN (cfun)) + { + gcc_assert (gimple_code (last_stmt (then_bb)) == GIMPLE_RETURN); + ret_val = gimple_return_retval (as_a(last_stmt (then_bb))); + + then_bb_succ_edge_flags = single_succ_edge (then_bb)->flags; + } + basic_block merge_bb = split_edge (single_succ_edge (then_bb)); + + /* Building return statement in merge_bb and setting merge_bb succ edge flags, + * if now merge_bb is pred of EXIT_BLOCK. */ + if (single_succ (merge_bb) == EXIT_BLOCK_PTR_FOR_FN (cfun)) + { + gimple* ret = gimple_build_return (ret_val); + gimple_stmt_iterator gsi = gsi_last_bb (merge_bb); + gsi_insert_after (&gsi, ret, GSI_NEW_STMT); + + single_succ_edge (merge_bb)->flags = then_bb_succ_edge_flags; + } + basic_block then_bb1 = duplicate_block (then_bb, outer_then_e, outer_cond_bb); edge outer_then1_e = find_edge (outer_cond_bb, then_bb1); @@ -372,6 +399,9 @@ make_two_separate_calls (basic_block outer_cond_bb, basic_block inner_cond_bb, set_immediate_dominator (CDI_POST_DOMINATORS, merge_bb, single_succ (merge_bb)); + if (get_immediate_dominator (CDI_POST_DOMINATORS, outer_cond_bb) == then_bb) + set_immediate_dominator (CDI_POST_DOMINATORS, outer_cond_bb, merge_bb); + return then_bb1; } @@ -548,6 +578,7 @@ pass_if_split::execute (function *fun) checking_verify_ssa (true, true); checking_verify_flow_info (); + checking_verify_loop_structure (); checking_verify_dominators (CDI_DOMINATORS); checking_verify_dominators (CDI_POST_DOMINATORS); @@ -564,4 +595,4 @@ gimple_opt_pass * make_pass_if_split (gcc::context *ctxt) { return new pass_if_split (ctxt); -} \ No newline at end of file +} -- 2.33.0