diff options
Diffstat (limited to 'gcc/tree-ssa-phiopt.c')
| -rw-r--r-- | gcc/tree-ssa-phiopt.c | 26 |
1 files changed, 19 insertions, 7 deletions
diff --git a/gcc/tree-ssa-phiopt.c b/gcc/tree-ssa-phiopt.c index 7987219..88c16e6 100644 --- a/gcc/tree-ssa-phiopt.c +++ b/gcc/tree-ssa-phiopt.c @@ -536,17 +536,21 @@ conditional_replacement (basic_block cond_bb, basic_block middle_bb, gimple_stmt_iterator gsi; edge true_edge, false_edge; tree new_var, new_var2; + bool neg; /* FIXME: Gimplification of complex type is too hard for now. */ if (TREE_CODE (TREE_TYPE (arg0)) == COMPLEX_TYPE || TREE_CODE (TREE_TYPE (arg1)) == COMPLEX_TYPE) return false; - /* The PHI arguments have the constants 0 and 1, then convert - it to the conditional. */ + /* The PHI arguments have the constants 0 and 1, or 0 and -1, then + convert it to the conditional. */ if ((integer_zerop (arg0) && integer_onep (arg1)) || (integer_zerop (arg1) && integer_onep (arg0))) - ; + neg = false; + else if ((integer_zerop (arg0) && integer_all_onesp (arg1)) + || (integer_zerop (arg1) && integer_all_onesp (arg0))) + neg = true; else return false; @@ -558,7 +562,7 @@ conditional_replacement (basic_block cond_bb, basic_block middle_bb, falls through into BB. There is a single PHI node at the join point (BB) and its arguments - are constants (0, 1). + are constants (0, 1) or (0, -1). So, given the condition COND, and the two PHI arguments, we can rewrite this PHI into non-branching code: @@ -585,11 +589,19 @@ conditional_replacement (basic_block cond_bb, basic_block middle_bb, edge so that we know when to invert the condition below. */ extract_true_false_edges_from_block (cond_bb, &true_edge, &false_edge); if ((e0 == true_edge && integer_zerop (arg0)) - || (e0 == false_edge && integer_onep (arg0)) + || (e0 == false_edge && !integer_zerop (arg0)) || (e1 == true_edge && integer_zerop (arg1)) - || (e1 == false_edge && integer_onep (arg1))) + || (e1 == false_edge && !integer_zerop (arg1))) cond = fold_build1_loc (gimple_location (stmt), - TRUTH_NOT_EXPR, TREE_TYPE (cond), cond); + TRUTH_NOT_EXPR, TREE_TYPE (cond), cond); + + if (neg) + { + cond = fold_convert_loc (gimple_location (stmt), + TREE_TYPE (result), cond); + cond = fold_build1_loc (gimple_location (stmt), + NEGATE_EXPR, TREE_TYPE (cond), cond); + } /* Insert our new statements at the end of conditional block before the COND_STMT. */ |