2 * Copyright (C) 1995-2008 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 * @brief Support for ir graph modification.
23 * @author Martin Trapp, Christian Schaefer, Goetz Lindenmaier
31 #include "irgraph_t.h"
36 #include "iredges_t.h"
41 * Turns a node into a "useless" Tuple. The Tuple just forms a tuple
42 * from several inputs.
43 * This is useful if a node returning a tuple is removed, but the Projs
44 * extracting values from the tuple are not available.
46 void turn_into_tuple(ir_node *node, int arity)
48 ir_graph *irg = get_irn_irg(node);
49 ir_node **in = ALLOCAN(ir_node*, arity);
50 ir_node *bad = new_r_Bad(irg, mode_ANY);
53 /* construct a new in array, with every input being bad */
54 for (i = 0; i < arity; ++i) {
57 set_irn_in(node, arity, in);
58 set_irn_op(node, op_Tuple);
62 * Insert irnode `new' in place of irnode `old'
63 * Since `new' may be bigger than `old' replace `old'
64 * by an op_Id which is smaller than everything.
66 void exchange(ir_node *old, ir_node *nw)
71 assert(old != nw && "Exchanging node with itself is not allowed");
73 irg = get_irn_irg(old);
74 assert(irg == get_irn_irg(nw) && "New node must be in same irg as old node");
76 hook_replace(old, nw);
79 * If new outs are on, we can skip the id node creation and reroute
80 * the edges from the old node to the new directly.
82 if (edges_activated(irg)) {
83 /* copy all dependencies from old to new */
84 add_irn_deps(nw, old);
86 edges_reroute(old, nw);
87 edges_reroute_kind(old, nw, EDGE_KIND_DEP);
88 edges_node_deleted(old);
89 /* noone is allowed to reference this node anymore */
90 set_irn_op(old, op_Deleted);
92 /* Else, do it the old-fashioned way. */
95 hook_turn_into_id(old);
99 block = is_Block(nw) ? nw : get_nodes_block(nw);
102 panic("cannot find legal block for id");
106 if (get_irn_op(old)->opar == oparity_dynamic) {
107 DEL_ARR_F(get_irn_in(old));
111 old->in = NEW_ARR_D (ir_node *, irg->obst, 2);
116 /* update irg flags */
117 clear_irg_state(irg, IR_GRAPH_STATE_CONSISTENT_OUTS
118 | IR_GRAPH_STATE_CONSISTENT_LOOPINFO);
121 /*--------------------------------------------------------------------*/
122 /* Functionality for collect_phis */
123 /*--------------------------------------------------------------------*/
126 * Walker: links all Phi nodes to their Blocks lists,
127 * all Proj nodes to there predecessors.
129 static void collect_phiprojs_walker(ir_node *n, void *env)
135 ir_node *block = get_nodes_block(n);
136 add_Block_phi(block, n);
137 } else if (is_Proj(n)) {
140 pred = get_Proj_pred(pred);
141 } while (is_Proj(pred));
143 set_irn_link(n, get_irn_link(pred));
144 set_irn_link(pred, n);
148 void collect_phiprojs(ir_graph *irg)
150 assert((ir_resources_reserved(irg) & (IR_RESOURCE_IRN_LINK|IR_RESOURCE_PHI_LIST)) ==
151 (IR_RESOURCE_IRN_LINK|IR_RESOURCE_PHI_LIST));
152 irg_walk_graph(irg, firm_clear_node_and_phi_links, collect_phiprojs_walker, NULL);
155 /*--------------------------------------------------------------------*/
156 /* Functionality for part_block */
157 /*--------------------------------------------------------------------*/
160 * Moves node and all predecessors of node from from_bl to to_bl.
161 * Does not move predecessors of Phi nodes (or block nodes).
163 static void move(ir_node *node, ir_node *from_bl, ir_node *to_bl)
168 set_nodes_block(node, to_bl);
171 if (get_irn_mode(node) == mode_T) {
172 ir_node *proj = (ir_node*)get_irn_link(node);
174 if (get_nodes_block(proj) == from_bl)
175 set_nodes_block(proj, to_bl);
176 proj = (ir_node*)get_irn_link(proj);
184 arity = get_irn_arity(node);
185 for (i = 0; i < arity; i++) {
186 ir_node *pred = get_irn_n(node, i);
187 if (get_nodes_block(pred) == from_bl)
188 move(pred, from_bl, to_bl);
192 static void move_projs(const ir_node *node, ir_node *to_bl)
194 const ir_edge_t *edge;
196 if (get_irn_mode(node) != mode_T)
199 foreach_out_edge(node, edge) {
200 ir_node *proj = get_edge_src_irn(edge);
203 set_nodes_block(proj, to_bl);
204 move_projs(proj, to_bl);
209 * Moves node and all predecessors of node from from_bl to to_bl.
210 * Does not move predecessors of Phi nodes (or block nodes).
212 static void move_edges(ir_node *node, ir_node *from_bl, ir_node *to_bl)
217 set_nodes_block(node, to_bl);
220 move_projs(node, to_bl);
222 /* We must not move predecessors of Phi nodes, even if they are in
223 * from_bl. (because these are values from an earlier loop iteration
224 * which are not predecessors of node here)
230 arity = get_irn_arity(node);
231 for (i = 0; i < arity; i++) {
232 ir_node *pred = get_irn_n(node, i);
233 if (get_nodes_block(pred) == from_bl)
234 move_edges(pred, from_bl, to_bl);
238 void part_block(ir_node *node)
240 ir_graph *irg = get_irn_irg(node);
241 ir_node *new_block, *old_block;
244 /* Turn off optimizations so that blocks are not merged again. */
245 int rem_opt = get_opt_optimize();
248 /* Transform the control flow */
249 old_block = get_nodes_block(node);
250 new_block = new_r_Block(irg, get_Block_n_cfgpreds(old_block),
251 get_Block_cfgpred_arr(old_block));
253 /* create a jump from new_block to old_block, which is now the lower one */
254 jmp = new_r_Jmp(new_block);
255 set_irn_in(old_block, 1, &jmp);
257 /* move node and its predecessors to new_block */
258 move(node, old_block, new_block);
260 /* move Phi nodes to new_block */
261 phi = get_Block_phis(old_block);
262 set_Block_phis(new_block, phi);
263 set_Block_phis(old_block, NULL);
265 set_nodes_block(phi, new_block);
266 phi = get_Phi_next(phi);
269 set_optimize(rem_opt);
272 ir_node *part_block_edges(ir_node *node)
274 ir_graph *irg = get_irn_irg(node);
275 ir_node *old_block = get_nodes_block(node);
276 ir_node *new_block = new_r_Block(irg,
277 get_Block_n_cfgpreds(old_block),
278 get_Block_cfgpred_arr(old_block));
279 const ir_edge_t *edge;
280 const ir_edge_t *next;
282 /* old_block has no predecessors anymore for now */
283 set_irn_in(old_block, 0, NULL);
285 /* move node and its predecessors to new_block */
286 move_edges(node, old_block, new_block);
288 /* move Phi nodes to new_block */
289 foreach_out_edge_safe(old_block, edge, next) {
290 ir_node *phi = get_edge_src_irn(edge);
293 set_nodes_block(phi, new_block);
299 void kill_node(ir_node *node)
301 ir_graph *irg = get_irn_irg(node);
303 if (edges_activated(irg)) {
304 edges_node_deleted(node);
306 /* noone is allowed to reference this node anymore */
307 set_irn_op(node, op_Deleted);