# include "irloop.h"
# include "debug.h"
-static firm_dbg_module_t *dbg;
+DEBUG_ONLY(static firm_dbg_module_t *dbg;)
typedef struct _walker_t {
int changes; /* set, if a reassociation take place */
t1 = get_binop_left(add_sub);
t2 = get_binop_right(add_sub);
- in[0] = new_rd_Mul(NULL, current_ir_graph, block, c, t1, mode);
- in[1] = new_rd_Mul(NULL, current_ir_graph, block, c, t2, mode);
+ /* we can only multiplication rules on integer arithmetic */
+ if (mode_is_int(get_irn_mode(t1)) && mode_is_int(get_irn_mode(t2))) {
+ in[0] = new_rd_Mul(NULL, current_ir_graph, block, c, t1, mode);
+ in[1] = new_rd_Mul(NULL, current_ir_graph, block, c, t2, mode);
- mode = get_mode_from_ops(in[0], in[1]);
- irn = optimize_node(new_ir_node(NULL, current_ir_graph, block, op, mode, 2, in));
+ mode = get_mode_from_ops(in[0], in[1]);
+ irn = optimize_node(new_ir_node(NULL, current_ir_graph, block, op, mode, 2, in));
- DBG((dbg, LEVEL_5, "Applied: (%n .%s. %n) %n %n => (%n %n %n) .%s. (%n %n %n)\n",
- t1, get_op_name(op), t2, n, c, t1, n, c, get_op_name(op), t2, n, c));
- exchange(n, irn);
- *node = irn;
+ /* In some cases it might happen that the new irn is equal the old one, for
+ * instance in:
+ * (x - 1) * y == x * y - y
+ * will be transformed back by simpler optimization
+ * We could switch simple optimizations off, but this only happens iff y
+ * is a loop-invariant expreassion and that it is not clear if the new form
+ * is better.
+ * So, we let the old one.
+ */
+ if (irn != n) {
+ DBG((dbg, LEVEL_5, "Applied: (%n .%s. %n) %n %n => (%n %n %n) .%s. (%n %n %n)\n",
+ t1, get_op_name(op), t2, n, c, t1, n, c, get_op_name(op), t2, n, c));
+ exchange(n, irn);
+ *node = irn;
- return 1;
+ return 1;
+ }
+ }
}
return 0;
}
/* initialize the reassociation by adding operations to some opcodes */
void firm_init_reassociation(void)
{
- dbg = firm_dbg_register("firm.opt.reassoc");
+ FIRM_DBG_REGISTER(dbg, "firm.opt.reassoc");
}