diff options
Diffstat (limited to 'gcc/tree-ssa-math-opts.c')
| -rw-r--r-- | gcc/tree-ssa-math-opts.c | 23 |
1 files changed, 18 insertions, 5 deletions
diff --git a/gcc/tree-ssa-math-opts.c b/gcc/tree-ssa-math-opts.c index 9544a6c..bff3c1d 100644 --- a/gcc/tree-ssa-math-opts.c +++ b/gcc/tree-ssa-math-opts.c @@ -69,6 +69,7 @@ execute_cse_reciprocals_1 (block_stmt_iterator *bsi, tree def, bool phi) imm_use_iterator use_iter; tree t, new_stmt, type; int count = 0; + bool ok = !flag_trapping_math; /* Find uses. */ FOR_EACH_IMM_USE_FAST (use_p, use_iter, def) @@ -77,13 +78,18 @@ execute_cse_reciprocals_1 (block_stmt_iterator *bsi, tree def, bool phi) if (TREE_CODE (use_stmt) == MODIFY_EXPR && TREE_CODE (TREE_OPERAND (use_stmt, 1)) == RDIV_EXPR && TREE_OPERAND (TREE_OPERAND (use_stmt, 1), 1) == def) - { - if (++count == 2) - break; - } + { + ++count; + /* Check if this use post-dominates the insertion point. */ + if (ok || dominated_by_p (CDI_POST_DOMINATORS, bsi->bb, + bb_for_stmt (use_stmt))) + ok = true; + } + if (count >= 2 && ok) + break; } - if (count < 2) + if (count < 2 || !ok) return; /* Make a variable with the replacement and substitute it. */ @@ -116,6 +122,10 @@ static void execute_cse_reciprocals (void) { basic_block bb; + + if (flag_trapping_math) + calculate_dominance_info (CDI_POST_DOMINATORS); + FOR_EACH_BB (bb) { block_stmt_iterator bsi; @@ -143,6 +153,9 @@ execute_cse_reciprocals (void) execute_cse_reciprocals_1 (&bsi, def, false); } } + + if (flag_trapping_math) + free_dominance_info (CDI_POST_DOMINATORS); } struct tree_opt_pass pass_cse_reciprocals = |