1 /*
2 * Copyright (c) 2009, 2016, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
23 package org.graalvm.compiler.nodes.cfg;
24
25 import java.util.ArrayList;
26 import java.util.Iterator;
27
28 import org.graalvm.compiler.core.common.cfg.AbstractBlockBase;
29 import org.graalvm.compiler.core.common.cfg.AbstractControlFlowGraph;
30 import org.graalvm.compiler.core.common.cfg.Loop;
31 import org.graalvm.compiler.graph.Node;
32 import org.graalvm.compiler.nodeinfo.Verbosity;
33 import org.graalvm.compiler.nodes.AbstractBeginNode;
34 import org.graalvm.compiler.nodes.BeginNode;
35 import org.graalvm.compiler.nodes.FixedNode;
36 import org.graalvm.compiler.nodes.FixedWithNextNode;
37 import org.graalvm.compiler.nodes.InvokeWithExceptionNode;
38 import org.graalvm.compiler.nodes.LoopBeginNode;
39 import org.graalvm.compiler.nodes.LoopEndNode;
40 import org.graalvm.compiler.nodes.LoopExitNode;
41 import org.graalvm.compiler.nodes.memory.MemoryCheckpoint;
42 import org.graalvm.word.LocationIdentity;
43
44 public final class Block extends AbstractBlockBase<Block> {
45
46 public static final Block[] EMPTY_ARRAY = new Block[0];
47
48 protected final AbstractBeginNode beginNode;
49
50 protected FixedNode endNode;
51
52 protected double probability;
53 private Loop<Block> loop;
54
55 protected Block postdominator;
56 protected Block distancedDominatorCache;
57 private LocationSet killLocations;
58 private LocationSet killLocationsBetweenThisAndDominator;
59
60 public Block(AbstractBeginNode node) {
61 this.beginNode = node;
62 }
63
64 public AbstractBeginNode getBeginNode() {
65 return beginNode;
66 }
67
68 public FixedNode getEndNode() {
69 return endNode;
70 }
71
72 /**
73 * Return the {@link LoopExitNode} for this block if it exists.
74 */
75 public LoopExitNode getLoopExit() {
76 if (beginNode instanceof BeginNode) {
77 if (beginNode.next() instanceof LoopExitNode) {
78 return (LoopExitNode) beginNode.next();
79 }
80 }
81 if (beginNode instanceof LoopExitNode) {
82 return (LoopExitNode) beginNode;
83 }
84 return null;
85 }
86
87 @Override
88 public Loop<Block> getLoop() {
89 return loop;
90 }
91
92 public void setLoop(Loop<Block> loop) {
93 this.loop = loop;
94 }
95
96 @Override
97 public int getLoopDepth() {
98 return loop == null ? 0 : loop.getDepth();
99 }
100
101 @Override
102 public boolean isLoopHeader() {
103 return getBeginNode() instanceof LoopBeginNode;
104 }
105
106 @Override
107 public boolean isLoopEnd() {
108 return getEndNode() instanceof LoopEndNode;
109 }
110
111 @Override
112 public boolean isExceptionEntry() {
113 Node predecessor = getBeginNode().predecessor();
114 return predecessor != null && predecessor instanceof InvokeWithExceptionNode && getBeginNode() == ((InvokeWithExceptionNode) predecessor).exceptionEdge();
115 }
116
117 public Block getFirstPredecessor() {
118 return getPredecessors()[0];
119 }
120
121 public Block getFirstSuccessor() {
122 return getSuccessors()[0];
123 }
124
125 public Block getEarliestPostDominated() {
126 Block b = this;
127 while (true) {
128 Block dom = b.getDominator();
129 if (dom != null && dom.getPostdominator() == b) {
130 b = dom;
131 } else {
132 break;
133 }
134 }
135 return b;
136 }
137
138 @Override
139 public Block getPostdominator() {
140 return postdominator;
141 }
142
143 private class NodeIterator implements Iterator<FixedNode> {
144
145 private FixedNode cur;
146
147 NodeIterator() {
148 cur = getBeginNode();
149 }
150
151 @Override
152 public boolean hasNext() {
153 return cur != null;
154 }
155
156 @Override
157 public FixedNode next() {
158 FixedNode result = cur;
159 if (result instanceof FixedWithNextNode) {
160 FixedWithNextNode fixedWithNextNode = (FixedWithNextNode) result;
161 FixedNode next = fixedWithNextNode.next();
162 if (next instanceof AbstractBeginNode) {
163 next = null;
164 }
165 cur = next;
166 } else {
167 cur = null;
168 }
169 assert !(cur instanceof AbstractBeginNode);
170 return result;
171 }
172
173 @Override
174 public void remove() {
175 throw new UnsupportedOperationException();
176 }
177 }
178
179 public Iterable<FixedNode> getNodes() {
180 return new Iterable<FixedNode>() {
181
182 @Override
183 public Iterator<FixedNode> iterator() {
184 return new NodeIterator();
185 }
186
187 @Override
188 public String toString() {
189 StringBuilder str = new StringBuilder().append('[');
190 for (FixedNode node : this) {
191 str.append(node).append(", ");
192 }
193 if (str.length() > 1) {
194 str.setLength(str.length() - 2);
195 }
196 return str.append(']').toString();
197 }
198 };
199 }
200
201 @Override
202 public String toString() {
203 return toString(Verbosity.Id);
204 }
205
206 public String toString(Verbosity verbosity) {
207 StringBuilder sb = new StringBuilder();
208 sb.append('B').append(id);
209 if (verbosity != Verbosity.Id) {
210 if (isLoopHeader()) {
211 sb.append(" lh");
212 }
213
214 if (getSuccessorCount() > 0) {
215 sb.append(" ->[");
216 for (int i = 0; i < getSuccessorCount(); ++i) {
217 if (i != 0) {
218 sb.append(',');
219 }
220 sb.append('B').append(getSuccessors()[i].getId());
221 }
222 sb.append(']');
223 }
224
225 if (getPredecessorCount() > 0) {
226 sb.append(" <-[");
227 for (int i = 0; i < getPredecessorCount(); ++i) {
228 if (i != 0) {
229 sb.append(',');
230 }
231 sb.append('B').append(getPredecessors()[i].getId());
232 }
233 sb.append(']');
234 }
235 }
236 return sb.toString();
237 }
238
239 @Override
240 public double probability() {
241 return probability;
242 }
243
244 public void setProbability(double probability) {
245 assert probability >= 0 && Double.isFinite(probability);
246 this.probability = probability;
247 }
248
249 @Override
250 public Block getDominator(int distance) {
251 Block result = this;
252 for (int i = 0; i < distance; ++i) {
253 result = result.getDominator();
254 }
255 return result;
256 }
257
258 public boolean canKill(LocationIdentity location) {
259 if (location.isImmutable()) {
260 return false;
261 }
262 return getKillLocations().contains(location);
263 }
264
265 public LocationSet getKillLocations() {
266 if (killLocations == null) {
267 killLocations = calcKillLocations();
268 }
269 return killLocations;
270 }
271
272 private LocationSet calcKillLocations() {
273 LocationSet result = new LocationSet();
274 for (FixedNode node : this.getNodes()) {
275 if (node instanceof MemoryCheckpoint.Single) {
276 LocationIdentity identity = ((MemoryCheckpoint.Single) node).getLocationIdentity();
277 result.add(identity);
278 } else if (node instanceof MemoryCheckpoint.Multi) {
279 for (LocationIdentity identity : ((MemoryCheckpoint.Multi) node).getLocationIdentities()) {
280 result.add(identity);
281 }
282 }
283 if (result.isAny()) {
284 break;
285 }
286 }
287 return result;
288 }
289
290 public boolean canKillBetweenThisAndDominator(LocationIdentity location) {
291 if (location.isImmutable()) {
292 return false;
293 }
294 return this.getKillLocationsBetweenThisAndDominator().contains(location);
295 }
296
297 private LocationSet getKillLocationsBetweenThisAndDominator() {
298 if (this.killLocationsBetweenThisAndDominator == null) {
299 LocationSet dominatorResult = new LocationSet();
300 Block stopBlock = getDominator();
301 if (this.isLoopHeader()) {
302 assert stopBlock.getLoopDepth() < this.getLoopDepth();
303 dominatorResult.addAll(((HIRLoop) this.getLoop()).getKillLocations());
304 } else {
305 for (Block b : this.getPredecessors()) {
306 assert !this.isLoopHeader();
307 if (b != stopBlock) {
308 dominatorResult.addAll(b.getKillLocations());
309 if (dominatorResult.isAny()) {
310 break;
311 }
312 b.calcKillLocationsBetweenThisAndTarget(dominatorResult, stopBlock);
313 if (dominatorResult.isAny()) {
314 break;
315 }
316 }
317 }
318 }
319 this.killLocationsBetweenThisAndDominator = dominatorResult;
320 }
321 return this.killLocationsBetweenThisAndDominator;
322 }
323
324 private void calcKillLocationsBetweenThisAndTarget(LocationSet result, Block stopBlock) {
325 assert AbstractControlFlowGraph.dominates(stopBlock, this);
326 if (stopBlock == this || result.isAny()) {
327 // We reached the stop block => nothing to do.
328 return;
329 } else {
330 if (stopBlock == this.getDominator()) {
331 result.addAll(this.getKillLocationsBetweenThisAndDominator());
332 } else {
333 // Divide and conquer: Aggregate kill locations from this to the dominator and then
334 // from the dominator onwards.
335 calcKillLocationsBetweenThisAndTarget(result, this.getDominator());
336 result.addAll(this.getDominator().getKillLocations());
337 if (result.isAny()) {
338 return;
339 }
340 this.getDominator().calcKillLocationsBetweenThisAndTarget(result, stopBlock);
341 }
342 }
343 }
344
345 @Override
346 public void delete() {
347
348 // adjust successor and predecessor lists
349 Block next = getSuccessors()[0];
350 for (Block pred : getPredecessors()) {
351 Block[] predSuccs = pred.successors;
352 Block[] newPredSuccs = new Block[predSuccs.length];
353 for (int i = 0; i < predSuccs.length; ++i) {
354 if (predSuccs[i] == this) {
355 newPredSuccs[i] = next;
356 } else {
357 newPredSuccs[i] = predSuccs[i];
358 }
359 }
360 pred.setSuccessors(newPredSuccs);
361 }
362
363 ArrayList<Block> newPreds = new ArrayList<>();
364 for (int i = 0; i < next.getPredecessorCount(); i++) {
365 Block curPred = next.getPredecessors()[i];
366 if (curPred == this) {
367 for (Block b : getPredecessors()) {
368 newPreds.add(b);
369 }
370 } else {
371 newPreds.add(curPred);
372 }
373 }
374
375 next.setPredecessors(newPreds.toArray(new Block[0]));
376 }
377
378 protected void setPostDominator(Block postdominator) {
379 this.postdominator = postdominator;
380 }
381 }