diff options
Diffstat (limited to 'gcc/tree-if-conv.cc')
| -rw-r--r-- | gcc/tree-if-conv.cc | 29 |
1 files changed, 25 insertions, 4 deletions
diff --git a/gcc/tree-if-conv.cc b/gcc/tree-if-conv.cc index 4531ca5..5b884aae 100644 --- a/gcc/tree-if-conv.cc +++ b/gcc/tree-if-conv.cc @@ -1298,10 +1298,31 @@ predicate_bbs (loop_p loop) tree c2; edge true_edge, false_edge; location_t loc = gimple_location (stmt); - tree c = build2_loc (loc, gimple_cond_code (stmt), - boolean_type_node, - gimple_cond_lhs (stmt), - gimple_cond_rhs (stmt)); + tree c; + /* gcc.dg/fold-bopcond-1.c shows that despite all forwprop passes + conditions can remain unfolded because of multiple uses so + try to re-fold here, especially to get precision changing + conversions sorted out. Do not simply fold the stmt since + this is analysis only. When conditions were embedded in + COND_EXPRs those were folded separately before folding the + COND_EXPR but as they are now outside we have to make sure + to fold them. Do it here - another opportunity would be to + fold predicates as they are inserted. */ + gimple_match_op cexpr (gimple_match_cond::UNCOND, + gimple_cond_code (stmt), + boolean_type_node, + gimple_cond_lhs (stmt), + gimple_cond_rhs (stmt)); + if (cexpr.resimplify (NULL, follow_all_ssa_edges) + && cexpr.code.is_tree_code () + && TREE_CODE_CLASS ((tree_code)cexpr.code) == tcc_comparison) + c = build2_loc (loc, (tree_code)cexpr.code, boolean_type_node, + cexpr.ops[0], cexpr.ops[1]); + else + c = build2_loc (loc, gimple_cond_code (stmt), + boolean_type_node, + gimple_cond_lhs (stmt), + gimple_cond_rhs (stmt)); /* Add new condition into destination's predicate list. */ extract_true_false_edges_from_block (gimple_bb (stmt), |