2 * Copyright (C) 1995-2007 University of Karlsruhe. All right reserved.
4 * This file is part of libFirm.
6 * This file may be distributed and/or modified under the terms of the
7 * GNU General Public License version 2 as published by the Free Software
8 * Foundation and appearing in the file LICENSE.GPL included in the
9 * packaging of this file.
11 * Licensees holding valid libFirm Professional Edition licenses may use
12 * this file in accordance with the libFirm Commercial License.
13 * Agreement provided with the Software.
15 * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
16 * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * @author Matthias Braun, Christoph Mallon
42 static lower_mode_b_config_t config;
43 static ir_type *lowered_type = NULL;
44 static pdeq *lowered_nodes = NULL;
47 * Removes a node if its out-edge count has reached 0.
48 * temporary hack until we have proper automatic dead code elimination.
50 static void maybe_kill_node(ir_node *node)
55 if(get_irn_n_edges(node) != 0)
58 irg = get_irn_irg(node);
60 assert(!is_Bad(node));
62 arity = get_irn_arity(node);
63 for (i = 0; i < arity; ++i) {
64 set_irn_n(node, i, new_Bad());
66 set_nodes_block(node, new_Bad());
68 edges_node_deleted(node, irg);
71 static ir_node *create_not(dbg_info *dbgi, ir_node *node)
73 ir_graph *irg = current_ir_graph;
74 ir_node *block = get_nodes_block(node);
75 ir_mode *mode = config.lowered_mode;
76 tarval *tv_one = get_tarval_one(mode);
77 ir_node *one = new_d_Const(dbgi, mode, tv_one);
79 return new_rd_Eor(dbgi, irg, block, node, one, mode);
82 static ir_node *create_convb(ir_node *node)
84 ir_graph *irg = current_ir_graph;
85 ir_node *block = get_nodes_block(node);
86 ir_node *conv = new_rd_Conv(NULL, irg, block, node, mode_b);
91 static ir_type *create_lowered_type(void)
93 if(lowered_type == NULL) {
94 lowered_type = new_type_primitive(new_id_from_str("__lowered_mode_b"),
101 * creates a "set" node that produces a 0 or 1 based on a Cmp result
103 static ir_node *create_set(ir_node *node)
105 ir_graph *irg = current_ir_graph;
106 dbg_info *dbgi = get_irn_dbg_info(node);
107 ir_mode *mode = config.lowered_set_mode;
108 tarval *tv_one = get_tarval_one(mode);
109 ir_node *one = new_d_Const(dbgi, mode, tv_one);
110 ir_node *block = get_nodes_block(node);
111 tarval *tv_zero = get_tarval_null(mode);
112 ir_node *zero = new_d_Const(dbgi, mode, tv_zero);
114 ir_node *vals[2] = { one, zero };
115 ir_node *set = new_rd_Psi(dbgi, irg, block, 1, &node, vals, mode);
117 if(mode != config.lowered_mode) {
118 set = new_r_Conv(irg, block, set, config.lowered_mode);
124 static void adjust_method_type(ir_type *method_type)
130 n_params = get_method_n_params(method_type);
131 for(i = 0; i < n_params; ++i) {
132 ir_type *param = get_method_param_type(method_type, i);
133 if(get_type_mode(param) == mode_b) {
134 set_method_param_type(method_type, i, create_lowered_type());
138 n_res = get_method_n_ress(method_type);
139 for(i = 0; i < n_res; ++i) {
140 ir_type *res_type = get_method_res_type(method_type, i);
141 if(get_type_mode(res_type) == mode_b) {
142 set_method_res_type(method_type, i, create_lowered_type());
147 static ir_node *lower_node(ir_node *node)
149 ir_graph *irg = current_ir_graph;
150 dbg_info *dbgi = get_irn_dbg_info(node);
151 ir_op *op = get_irn_op(node);
152 ir_node *block = get_nodes_block(node);
153 ir_mode *mode = config.lowered_mode;
156 assert(get_irn_mode(node) == mode_b);
158 res = get_irn_link(node);
162 /* TODO: be robust against phi-loops... */
166 ir_node *unknown, *new_phi;
168 arity = get_irn_arity(node);
169 in = alloca(arity * sizeof(in[0]));
170 unknown = new_Unknown(config.lowered_mode);
171 for(i = 0; i < arity; ++i) {
174 new_phi = new_r_Phi(irg, block, arity, in, config.lowered_mode);
175 set_irn_link(node, new_phi);
176 pdeq_putr(lowered_nodes, node);
178 for(i = 0; i < arity; ++i) {
179 ir_node *in = get_irn_n(node, i);
180 ir_node *low_in = lower_node(in);
182 set_irn_n(new_phi, i, low_in);
188 if(op == op_And || op == op_Or || op == op_Eor) {
190 ir_node *copy = exact_copy(node);
192 arity = get_irn_arity(node);
193 for(i = 0; i < arity; ++i) {
194 ir_node *in = get_irn_n(node, i);
195 ir_node *low_in = lower_node(in);
197 set_irn_n(copy, i, low_in);
199 set_irn_mode(copy, config.lowered_mode);
201 set_irn_link(node, copy);
202 pdeq_putr(lowered_nodes, node);
206 ir_node *op = get_Not_op(node);
207 ir_node *low_op = lower_node(op);
209 res = create_not(dbgi, low_op);
210 set_irn_link(node, res);
211 pdeq_putr(lowered_nodes, node);
215 ir_node *cond = get_Psi_cond(node, 0);
216 ir_node *low_cond = lower_node(cond);
217 ir_node *v_true = get_Psi_val(node, 0);
218 ir_node *low_v_true = lower_node(v_true);
219 ir_node *v_false = get_Psi_default(node);
220 ir_node *low_v_false = lower_node(v_false);
222 ir_node *and0 = new_rd_And(dbgi, irg, block, low_cond, low_v_true,
225 ir_node *not_cond = create_not(dbgi, low_cond);
227 ir_node *and1 = new_rd_And(dbgi, irg, block, not_cond, low_v_false,
230 ir_node *or = new_rd_Or(dbgi, irg, block, and0, and1,
233 set_irn_link(node, or);
234 pdeq_putr(lowered_nodes, node);
238 ir_node *pred = get_Conv_op(node);
239 ir_mode *mode = get_irn_mode(pred);
240 tarval *tv_zeroc = get_tarval_null(mode);
241 ir_node *zero_cmp = new_d_Const(dbgi, mode, tv_zeroc);
244 ir_node *cmp = new_rd_Cmp(dbgi, irg, block, pred, zero_cmp);
245 ir_node *proj = new_rd_Proj(dbgi, irg, block, cmp, mode_b,
247 set = create_set(proj);
249 set_irn_link(node, set);
250 pdeq_putr(lowered_nodes, node);
254 ir_node *pred = get_Proj_pred(node);
257 ir_node *left = get_Cmp_left(pred);
258 ir_node *right = get_Cmp_right(pred);
259 ir_mode *cmp_mode = get_irn_mode(left);
262 if ((mode_is_int(cmp_mode) || mode_is_reference(cmp_mode)) && (
263 get_mode_size_bits(cmp_mode) < get_mode_size_bits(mode) ||
264 (mode_is_signed(cmp_mode) && is_Const(right) && is_Const_null(right))
266 int pnc = get_Proj_proj(node);
271 if(pnc == pn_Cmp_Lt) {
272 /* a < b -> (a - b) >> 31 */
275 } else if(pnc == pn_Cmp_Le) {
276 /* a <= b -> ~(a - b) >> 31 */
280 } else if(pnc == pn_Cmp_Gt) {
281 /* a > b -> (b - a) >> 31 */
284 } else if(pnc == pn_Cmp_Ge) {
285 /* a >= b -> ~(a - b) >> 31 */
292 int bits = get_mode_size_bits(mode);
293 tarval *tv = new_tarval_from_long(bits-1, mode_Iu);
294 ir_node *shift_cnt = new_d_Const(dbgi, mode_Iu, tv);
296 if(cmp_mode != mode) {
297 a = new_rd_Conv(dbgi, irg, block, a, mode);
298 b = new_rd_Conv(dbgi, irg, block, b, mode);
301 res = new_rd_Sub(dbgi, irg, block, a, b, mode);
303 res = new_rd_Not(dbgi, irg, block, res, mode);
305 res = new_rd_Shr(dbgi, irg, block, res, shift_cnt, mode);
307 set_irn_link(node, res);
308 pdeq_putr(lowered_nodes, node);
313 /* synthesize the 0/1 value */
314 set = create_set(node);
315 set_irn_link(node, set);
316 pdeq_putr(lowered_nodes, node);
318 } else if(is_Proj(pred) && is_Call(get_Proj_pred(pred))) {
319 ir_type *type = get_Call_type(get_Proj_pred(pred));
320 adjust_method_type(type);
321 set_irn_mode(node, mode);
323 } else if(is_Proj(pred) && is_Start(get_Proj_pred(pred))) {
324 ir_entity *entity = get_irg_entity(irg);
325 ir_type *type = get_entity_type(entity);
326 adjust_method_type(type);
327 set_irn_mode(node, mode);
331 panic("unexpected projb: %+F (pred: %+F)", node, pred);
334 tarval *tv = get_Const_tarval(node);
335 if(tv == get_tarval_b_true()) {
336 tarval *tv_one = get_tarval_one(mode);
337 res = new_d_Const(dbgi, mode, tv_one);
338 } else if(tv == get_tarval_b_false()) {
339 tarval *tv_zero = get_tarval_null(mode);
340 res = new_d_Const(dbgi, mode, tv_zero);
342 panic("invalid boolean const %+F", node);
344 set_irn_link(node, res);
345 pdeq_putr(lowered_nodes, node);
348 if (op == op_Unknown) {
349 return new_Unknown(config.lowered_mode);
352 panic("didn't expect %+F to have mode_b", node);
355 static void lower_mode_b_walker(ir_node *node, void *env)
361 arity = get_irn_arity(node);
362 for(i = 0; i < arity; ++i) {
364 ir_node *in = get_irn_n(node, i);
365 if(get_irn_mode(in) != mode_b)
368 if(! config.lower_direct_cmp) {
370 || (is_Psi(node) && get_irn_mode(node) != mode_b)) {
372 ir_node *pred = get_Proj_pred(in);
379 lowered_in = lower_node(in);
381 if(is_Return(node)) {
382 ir_entity *entity = get_irg_entity(current_ir_graph);
383 ir_type *type = get_entity_type(entity);
384 adjust_method_type(type);
385 } else if(is_Call(node)) {
386 ir_type *type = get_Call_type(node);
387 adjust_method_type(type);
389 lowered_in = create_convb(lowered_in);
391 set_irn_n(node, i, lowered_in);
395 add_identities(current_ir_graph->value_table, node);
399 static void clear_links(ir_node *node, void *env)
402 set_irn_link(node, NULL);
405 void ir_lower_mode_b(ir_graph *irg, const lower_mode_b_config_t *nconfig)
408 lowered_nodes = new_pdeq();
409 set_using_irn_link(irg);
411 irg_walk_graph(irg, clear_links, NULL, NULL);
412 irg_walk_graph(irg, lower_mode_b_walker, NULL, NULL);
414 while(!pdeq_empty(lowered_nodes)) {
415 ir_node *node = (ir_node*) pdeq_getr(lowered_nodes);
416 maybe_kill_node(node);
418 del_pdeq(lowered_nodes);
420 clear_using_irn_link(irg);