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);
52 /* construct a new in array, with every input being bad */
53 for (i = 0; i < arity; ++i) {
54 in[i] = new_r_Bad(irg);
56 set_irn_in(node, arity, in);
57 set_irn_op(node, op_Tuple);
61 * Insert irnode `new' in place of irnode `old'
62 * Since `new' may be bigger than `old' replace `old'
63 * by an op_Id which is smaller than everything.
65 void exchange(ir_node *old, ir_node *nw)
70 assert(old != nw && "Exchanging node with itself is not allowed");
72 irg = get_irn_irg(old);
73 assert(irg == get_irn_irg(nw) && "New node must be in same irg as old node");
75 hook_replace(old, nw);
78 * If new outs are on, we can skip the id node creation and reroute
79 * the edges from the old node to the new directly.
81 if (edges_activated(irg)) {
82 /* copy all dependencies from old to new */
83 add_irn_deps(nw, old);
85 edges_reroute(old, nw);
86 edges_reroute_kind(old, nw, EDGE_KIND_DEP);
87 edges_node_deleted(old);
88 /* noone is allowed to reference this node anymore */
89 set_irn_op(old, op_Deleted);
91 /* Else, do it the old-fashioned way. */
94 hook_turn_into_id(old);
98 block = is_Block(nw) ? nw : get_nodes_block(nw);
101 panic("cannot find legal block for id");
105 if (get_irn_op(old)->opar == oparity_dynamic) {
106 DEL_ARR_F(get_irn_in(old));
110 old->in = NEW_ARR_D (ir_node *, irg->obst, 2);
116 /*--------------------------------------------------------------------*/
117 /* Functionality for collect_phis */
118 /*--------------------------------------------------------------------*/
121 * Walker: links all Phi nodes to their Blocks lists,
122 * all Proj nodes to there predecessors.
124 static void collect_phiprojs_walker(ir_node *n, void *env)
130 ir_node *block = get_nodes_block(n);
131 add_Block_phi(block, n);
132 } else if (is_Proj(n)) {
135 pred = get_Proj_pred(pred);
136 } while (is_Proj(pred));
138 set_irn_link(n, get_irn_link(pred));
139 set_irn_link(pred, n);
143 void collect_phiprojs(ir_graph *irg)
145 assert((ir_resources_reserved(irg) & (IR_RESOURCE_IRN_LINK|IR_RESOURCE_PHI_LIST)) ==
146 (IR_RESOURCE_IRN_LINK|IR_RESOURCE_PHI_LIST));
147 irg_walk_graph(irg, firm_clear_node_and_phi_links, collect_phiprojs_walker, NULL);
150 /*--------------------------------------------------------------------*/
151 /* Functionality for part_block */
152 /*--------------------------------------------------------------------*/
155 * Moves node and all predecessors of node from from_bl to to_bl.
156 * Does not move predecessors of Phi nodes (or block nodes).
158 static void move(ir_node *node, ir_node *from_bl, ir_node *to_bl)
163 set_nodes_block(node, to_bl);
166 if (get_irn_mode(node) == mode_T) {
167 ir_node *proj = (ir_node*)get_irn_link(node);
169 if (get_nodes_block(proj) == from_bl)
170 set_nodes_block(proj, to_bl);
171 proj = (ir_node*)get_irn_link(proj);
179 arity = get_irn_arity(node);
180 for (i = 0; i < arity; i++) {
181 ir_node *pred = get_irn_n(node, i);
182 if (get_nodes_block(pred) == from_bl)
183 move(pred, from_bl, to_bl);
188 * Moves node and all predecessors of node from from_bl to to_bl.
189 * Does not move predecessors of Phi nodes (or block nodes).
191 static void move_edges(ir_node *node, ir_node *from_bl, ir_node *to_bl)
196 set_nodes_block(node, to_bl);
199 if (get_irn_mode(node) == mode_T) {
200 const ir_edge_t *edge;
201 foreach_out_edge(node, edge) {
202 ir_node *proj = get_edge_src_irn(edge);
203 set_nodes_block(proj, to_bl);
207 /* We must not move predecessors of Phi nodes, even if they are in
208 * from_bl. (because these are values from an earlier loop iteration
209 * which are not predecessors of node here)
215 arity = get_irn_arity(node);
216 for (i = 0; i < arity; i++) {
217 ir_node *pred = get_irn_n(node, i);
218 if (get_nodes_block(pred) == from_bl)
219 move_edges(pred, from_bl, to_bl);
223 void part_block(ir_node *node)
225 ir_graph *irg = get_irn_irg(node);
226 ir_node *new_block, *old_block;
229 /* Turn off optimizations so that blocks are not merged again. */
230 int rem_opt = get_opt_optimize();
233 /* Transform the control flow */
234 old_block = get_nodes_block(node);
235 new_block = new_r_Block(irg, get_Block_n_cfgpreds(old_block),
236 get_Block_cfgpred_arr(old_block));
238 /* create a jump from new_block to old_block, which is now the lower one */
239 jmp = new_r_Jmp(new_block);
240 set_irn_in(old_block, 1, &jmp);
242 /* move node and its predecessors to new_block */
243 move(node, old_block, new_block);
245 /* move Phi nodes to new_block */
246 phi = get_Block_phis(old_block);
247 set_Block_phis(new_block, phi);
248 set_Block_phis(old_block, NULL);
250 set_nodes_block(phi, new_block);
251 phi = get_Phi_next(phi);
254 set_optimize(rem_opt);
257 ir_node *part_block_edges(ir_node *node)
259 ir_graph *irg = get_irn_irg(node);
260 ir_node *old_block = get_nodes_block(node);
261 ir_node *new_block = new_r_Block(irg,
262 get_Block_n_cfgpreds(old_block),
263 get_Block_cfgpred_arr(old_block));
264 const ir_edge_t *edge;
265 const ir_edge_t *next;
267 /* old_block has no predecessors anymore for now */
268 set_irn_in(old_block, 0, NULL);
270 /* move node and its predecessors to new_block */
271 move_edges(node, old_block, new_block);
273 /* move Phi nodes to new_block */
274 foreach_out_edge_safe(old_block, edge, next) {
275 ir_node *phi = get_edge_src_irn(edge);
278 set_nodes_block(phi, new_block);
284 void kill_node(ir_node *node)
286 ir_graph *irg = get_irn_irg(node);
287 ir_node *bad = get_irg_bad(irg);
290 for (i = get_irn_arity(node) - 1; i >= -1; --i) {
291 set_irn_n(node, i, bad);