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
24
25 package org.graalvm.compiler.nodes.cfg;
26
27 import java.util.ArrayList;
28 import java.util.Iterator;
29
30 import org.graalvm.compiler.core.common.cfg.AbstractBlockBase;
31 import org.graalvm.compiler.core.common.cfg.AbstractControlFlowGraph;
32 import org.graalvm.compiler.core.common.cfg.Loop;
33 import org.graalvm.compiler.graph.Node;
34 import org.graalvm.compiler.nodeinfo.Verbosity;
35 import org.graalvm.compiler.nodes.AbstractBeginNode;
36 import org.graalvm.compiler.nodes.BeginNode;
37 import org.graalvm.compiler.nodes.FixedNode;
38 import org.graalvm.compiler.nodes.FixedWithNextNode;
39 import org.graalvm.compiler.nodes.InvokeWithExceptionNode;
40 import org.graalvm.compiler.nodes.LoopBeginNode;
41 import org.graalvm.compiler.nodes.LoopEndNode;
42 import org.graalvm.compiler.nodes.LoopExitNode;
43 import org.graalvm.compiler.nodes.memory.MemoryCheckpoint;
44 import jdk.internal.vm.compiler.word.LocationIdentity;
45
46 public final class Block extends AbstractBlockBase<Block> {
47 public static final Block[] EMPTY_ARRAY = new Block[0];
48
49 protected final AbstractBeginNode beginNode;
50
51 protected FixedNode endNode;
52
53 protected double relativeFrequency;
54 private Loop<Block> loop;
55
56 protected Block postdominator;
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 /**
240 * The execution frequency of this block relative to the start block as estimated by the
241 * profiling information.
242 */
243 @Override
244 public double getRelativeFrequency() {
245 return relativeFrequency;
246 }
247
248 public void setRelativeFrequency(double relativeFrequency) {
249 assert relativeFrequency >= 0 && Double.isFinite(relativeFrequency);
250 this.relativeFrequency = relativeFrequency;
251 }
252
253 @Override
254 public Block getDominator(int distance) {
255 Block result = this;
256 for (int i = 0; i < distance; ++i) {
257 result = result.getDominator();
258 }
259 return result;
260 }
261
262 public boolean canKill(LocationIdentity location) {
263 if (location.isImmutable()) {
264 return false;
265 }
266 return getKillLocations().contains(location);
267 }
268
269 public LocationSet getKillLocations() {
270 if (killLocations == null) {
271 killLocations = calcKillLocations();
272 }
273 return killLocations;
274 }
275
276 private LocationSet calcKillLocations() {
277 LocationSet result = new LocationSet();
278 for (FixedNode node : this.getNodes()) {
279 if (node instanceof MemoryCheckpoint.Single) {
280 LocationIdentity identity = ((MemoryCheckpoint.Single) node).getLocationIdentity();
281 result.add(identity);
282 } else if (node instanceof MemoryCheckpoint.Multi) {
283 for (LocationIdentity identity : ((MemoryCheckpoint.Multi) node).getLocationIdentities()) {
284 result.add(identity);
285 }
286 }
287 if (result.isAny()) {
288 break;
289 }
290 }
291 return result;
292 }
293
294 public boolean canKillBetweenThisAndDominator(LocationIdentity location) {
295 if (location.isImmutable()) {
296 return false;
297 }
298 return this.getKillLocationsBetweenThisAndDominator().contains(location);
299 }
300
301 private LocationSet getKillLocationsBetweenThisAndDominator() {
302 if (this.killLocationsBetweenThisAndDominator == null) {
303 LocationSet dominatorResult = new LocationSet();
304 Block stopBlock = getDominator();
305 if (this.isLoopHeader()) {
306 assert stopBlock.getLoopDepth() < this.getLoopDepth();
307 dominatorResult.addAll(((HIRLoop) this.getLoop()).getKillLocations());
308 } else {
309 for (Block b : this.getPredecessors()) {
310 assert !this.isLoopHeader();
311 if (b != stopBlock) {
312 dominatorResult.addAll(b.getKillLocations());
313 if (dominatorResult.isAny()) {
314 break;
315 }
316 b.calcKillLocationsBetweenThisAndTarget(dominatorResult, stopBlock);
317 if (dominatorResult.isAny()) {
318 break;
319 }
320 }
321 }
322 }
323 this.killLocationsBetweenThisAndDominator = dominatorResult;
324 }
325 return this.killLocationsBetweenThisAndDominator;
326 }
327
328 private void calcKillLocationsBetweenThisAndTarget(LocationSet result, Block stopBlock) {
329 assert AbstractControlFlowGraph.dominates(stopBlock, this);
330 if (stopBlock == this || result.isAny()) {
331 // We reached the stop block => nothing to do.
332 return;
333 } else {
334 if (stopBlock == this.getDominator()) {
335 result.addAll(this.getKillLocationsBetweenThisAndDominator());
336 } else {
337 // Divide and conquer: Aggregate kill locations from this to the dominator and then
338 // from the dominator onwards.
339 calcKillLocationsBetweenThisAndTarget(result, this.getDominator());
340 result.addAll(this.getDominator().getKillLocations());
341 if (result.isAny()) {
342 return;
343 }
344 this.getDominator().calcKillLocationsBetweenThisAndTarget(result, stopBlock);
345 }
346 }
347 }
348
349 @Override
350 public void delete() {
351
352 // adjust successor and predecessor lists
353 Block next = getSuccessors()[0];
354 for (Block pred : getPredecessors()) {
355 Block[] predSuccs = pred.successors;
356 Block[] newPredSuccs = new Block[predSuccs.length];
357 for (int i = 0; i < predSuccs.length; ++i) {
358 if (predSuccs[i] == this) {
359 newPredSuccs[i] = next;
360 } else {
361 newPredSuccs[i] = predSuccs[i];
362 }
363 }
364 pred.setSuccessors(newPredSuccs);
365 }
366
367 ArrayList<Block> newPreds = new ArrayList<>();
368 for (int i = 0; i < next.getPredecessorCount(); i++) {
369 Block curPred = next.getPredecessors()[i];
370 if (curPred == this) {
371 for (Block b : getPredecessors()) {
372 newPreds.add(b);
373 }
374 } else {
375 newPreds.add(curPred);
376 }
377 }
378
379 next.setPredecessors(newPreds.toArray(new Block[0]));
380 }
381
382 protected void setPostDominator(Block postdominator) {
383 this.postdominator = postdominator;
384 }
385 }