don't forget to check the sign of a float number, this fixes fehler142

[r21638]

diff --git a/ir/ir/iropt.c b/ir/ir/iropt.c
index af2c377..359b500 100644 (file)
--- a/ir/ir/iropt.c
+++ b/ir/ir/iropt.c
@@ -2718,7 +2718,8 @@ static ir_node *transform_node_Mul(ir_node *n) {
        if (get_mode_arithmetic(mode) == irma_ieee754) {
                if (is_Const(a)) {
                        tarval *tv = get_Const_tarval(a);
-                       if (tarval_ieee754_get_exponent(tv) == 1 && tarval_ieee754_zero_mantissa(tv)) {
+                       if (tarval_ieee754_get_exponent(tv) == 1 && tarval_ieee754_zero_mantissa(tv)
+                                       && !tarval_is_negative(tv)) {
                                /* 2.0 * b = b + b */
                                n = new_rd_Add(get_irn_dbg_info(n), current_ir_graph, get_nodes_block(n), b, b, mode);
                                DBG_OPT_ALGSIM1(oldn, a, b, n, FS_OPT_ADD_A_A);
@@ -2727,7 +2728,8 @@ static ir_node *transform_node_Mul(ir_node *n) {
                }
                else if (is_Const(b)) {
                        tarval *tv = get_Const_tarval(b);
-                       if (tarval_ieee754_get_exponent(tv) == 1 && tarval_ieee754_zero_mantissa(tv)) {
+                       if (tarval_ieee754_get_exponent(tv) == 1 && tarval_ieee754_zero_mantissa(tv)
+                                       && !tarval_is_negative(tv)) {
                                /* a * 2.0 = a + a */
                                n = new_rd_Add(get_irn_dbg_info(n), current_ir_graph, get_nodes_block(n), a, a, mode);
                                DBG_OPT_ALGSIM1(oldn, a, b, n, FS_OPT_ADD_A_A);