1 /*
2 * Copyright (c) 2009, 2019, 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.FixedNode;
37 import org.graalvm.compiler.nodes.FixedWithNextNode;
38 import org.graalvm.compiler.nodes.InvokeWithExceptionNode;
39 import org.graalvm.compiler.nodes.LoopBeginNode;
40 import org.graalvm.compiler.nodes.LoopEndNode;
41 import org.graalvm.compiler.nodes.memory.MemoryCheckpoint;
42 import jdk.internal.vm.compiler.word.LocationIdentity;
43
44 public final class Block extends AbstractBlockBase<Block> {
45 public static final Block[] EMPTY_ARRAY = new Block[0];
46
47 protected final AbstractBeginNode beginNode;
48
49 protected FixedNode endNode;
50
51 protected double relativeFrequency;
52 private Loop<Block> loop;
53
54 protected Block postdominator;
55 private LocationSet killLocations;
56 private LocationSet killLocationsBetweenThisAndDominator;
57
58 public Block(AbstractBeginNode node) {
59 this.beginNode = node;
60 }
61
62 public AbstractBeginNode getBeginNode() {
63 return beginNode;
64 }
65
66 public FixedNode getEndNode() {
67 return endNode;
68 }
69
70 @Override
71 public Loop<Block> getLoop() {
72 return loop;
73 }
74
75 public void setLoop(Loop<Block> loop) {
76 this.loop = loop;
77 }
78
79 @Override
80 public int getLoopDepth() {
81 return loop == null ? 0 : loop.getDepth();
82 }
83
84 @Override
85 public boolean isLoopHeader() {
86 return getBeginNode() instanceof LoopBeginNode;
87 }
88
89 @Override
90 public boolean isLoopEnd() {
91 return getEndNode() instanceof LoopEndNode;
92 }
93
94 @Override
95 public boolean isExceptionEntry() {
96 Node predecessor = getBeginNode().predecessor();
97 return predecessor != null && predecessor instanceof InvokeWithExceptionNode && getBeginNode() == ((InvokeWithExceptionNode) predecessor).exceptionEdge();
98 }
99
100 public Block getFirstPredecessor() {
101 return getPredecessors()[0];
102 }
103
104 public Block getFirstSuccessor() {
105 return getSuccessors()[0];
106 }
107
108 public Block getEarliestPostDominated() {
109 Block b = this;
110 while (true) {
111 Block dom = b.getDominator();
112 if (dom != null && dom.getPostdominator() == b) {
113 b = dom;
114 } else {
115 break;
116 }
117 }
118 return b;
119 }
120
121 @Override
122 public Block getPostdominator() {
123 return postdominator;
124 }
125
126 private class NodeIterator implements Iterator<FixedNode> {
127
128 private FixedNode cur;
129
130 NodeIterator() {
131 cur = getBeginNode();
132 }
133
134 @Override
135 public boolean hasNext() {
136 return cur != null;
137 }
138
139 @Override
140 public FixedNode next() {
141 FixedNode result = cur;
142 if (result instanceof FixedWithNextNode) {
143 FixedWithNextNode fixedWithNextNode = (FixedWithNextNode) result;
144 FixedNode next = fixedWithNextNode.next();
145 if (next instanceof AbstractBeginNode) {
146 next = null;
147 }
148 cur = next;
149 } else {
150 cur = null;
151 }
152 assert !(cur instanceof AbstractBeginNode);
153 return result;
154 }
155
156 @Override
157 public void remove() {
158 throw new UnsupportedOperationException();
159 }
160 }
161
162 public Iterable<FixedNode> getNodes() {
163 return new Iterable<FixedNode>() {
164
165 @Override
166 public Iterator<FixedNode> iterator() {
167 return new NodeIterator();
168 }
169
170 @Override
171 public String toString() {
172 StringBuilder str = new StringBuilder().append('[');
173 for (FixedNode node : this) {
174 str.append(node).append(", ");
175 }
176 if (str.length() > 1) {
177 str.setLength(str.length() - 2);
178 }
179 return str.append(']').toString();
180 }
181 };
182 }
183
184 @Override
185 public String toString() {
186 return toString(Verbosity.Id);
187 }
188
189 public String toString(Verbosity verbosity) {
190 StringBuilder sb = new StringBuilder();
191 sb.append('B').append(id);
192 if (verbosity != Verbosity.Id) {
193 if (isLoopHeader()) {
194 sb.append(" lh");
195 }
196
197 if (getSuccessorCount() > 0) {
198 sb.append(" ->[");
199 for (int i = 0; i < getSuccessorCount(); ++i) {
200 if (i != 0) {
201 sb.append(',');
202 }
203 sb.append('B').append(getSuccessors()[i].getId());
204 }
205 sb.append(']');
206 }
207
208 if (getPredecessorCount() > 0) {
209 sb.append(" <-[");
210 for (int i = 0; i < getPredecessorCount(); ++i) {
211 if (i != 0) {
212 sb.append(',');
213 }
214 sb.append('B').append(getPredecessors()[i].getId());
215 }
216 sb.append(']');
217 }
218 }
219 return sb.toString();
220 }
221
222 /**
223 * The execution frequency of this block relative to the start block as estimated by the
224 * profiling information.
225 */
226 @Override
227 public double getRelativeFrequency() {
228 return relativeFrequency;
229 }
230
231 public void setRelativeFrequency(double relativeFrequency) {
232 assert relativeFrequency >= 0 && Double.isFinite(relativeFrequency);
233 this.relativeFrequency = relativeFrequency;
234 }
235
236 @Override
237 public Block getDominator(int distance) {
238 Block result = this;
239 for (int i = 0; i < distance; ++i) {
240 result = result.getDominator();
241 }
242 return result;
243 }
244
245 public boolean canKill(LocationIdentity location) {
246 if (location.isImmutable()) {
247 return false;
248 }
249 return getKillLocations().contains(location);
250 }
251
252 public LocationSet getKillLocations() {
253 if (killLocations == null) {
254 killLocations = calcKillLocations();
255 }
256 return killLocations;
257 }
258
259 private LocationSet calcKillLocations() {
260 LocationSet result = new LocationSet();
261 for (FixedNode node : this.getNodes()) {
262 if (node instanceof MemoryCheckpoint.Single) {
263 LocationIdentity identity = ((MemoryCheckpoint.Single) node).getLocationIdentity();
264 result.add(identity);
265 } else if (node instanceof MemoryCheckpoint.Multi) {
266 for (LocationIdentity identity : ((MemoryCheckpoint.Multi) node).getLocationIdentities()) {
267 result.add(identity);
268 }
269 }
270 if (result.isAny()) {
271 break;
272 }
273 }
274 return result;
275 }
276
277 public boolean canKillBetweenThisAndDominator(LocationIdentity location) {
278 if (location.isImmutable()) {
279 return false;
280 }
281 return this.getKillLocationsBetweenThisAndDominator().contains(location);
282 }
283
284 private LocationSet getKillLocationsBetweenThisAndDominator() {
285 if (this.killLocationsBetweenThisAndDominator == null) {
286 LocationSet dominatorResult = new LocationSet();
287 Block stopBlock = getDominator();
288 if (this.isLoopHeader()) {
289 assert stopBlock.getLoopDepth() < this.getLoopDepth();
290 dominatorResult.addAll(((HIRLoop) this.getLoop()).getKillLocations());
291 } else {
292 for (Block b : this.getPredecessors()) {
293 assert !this.isLoopHeader();
294 if (b != stopBlock) {
295 dominatorResult.addAll(b.getKillLocations());
296 if (dominatorResult.isAny()) {
297 break;
298 }
299 b.calcKillLocationsBetweenThisAndTarget(dominatorResult, stopBlock);
300 if (dominatorResult.isAny()) {
301 break;
302 }
303 }
304 }
305 }
306 this.killLocationsBetweenThisAndDominator = dominatorResult;
307 }
308 return this.killLocationsBetweenThisAndDominator;
309 }
310
311 private void calcKillLocationsBetweenThisAndTarget(LocationSet result, Block stopBlock) {
312 assert AbstractControlFlowGraph.dominates(stopBlock, this);
313 if (stopBlock == this || result.isAny()) {
314 // We reached the stop block => nothing to do.
315 return;
316 } else {
317 if (stopBlock == this.getDominator()) {
318 result.addAll(this.getKillLocationsBetweenThisAndDominator());
319 } else {
320 // Divide and conquer: Aggregate kill locations from this to the dominator and then
321 // from the dominator onwards.
322 calcKillLocationsBetweenThisAndTarget(result, this.getDominator());
323 result.addAll(this.getDominator().getKillLocations());
324 if (result.isAny()) {
325 return;
326 }
327 this.getDominator().calcKillLocationsBetweenThisAndTarget(result, stopBlock);
328 }
329 }
330 }
331
332 @Override
333 public void delete() {
334
335 // adjust successor and predecessor lists
336 Block next = getSuccessors()[0];
337 for (Block pred : getPredecessors()) {
338 Block[] predSuccs = pred.successors;
339 Block[] newPredSuccs = new Block[predSuccs.length];
340 for (int i = 0; i < predSuccs.length; ++i) {
341 if (predSuccs[i] == this) {
342 newPredSuccs[i] = next;
343 } else {
344 newPredSuccs[i] = predSuccs[i];
345 }
346 }
347 pred.setSuccessors(newPredSuccs);
348 }
349
350 ArrayList<Block> newPreds = new ArrayList<>();
351 for (int i = 0; i < next.getPredecessorCount(); i++) {
352 Block curPred = next.getPredecessors()[i];
353 if (curPred == this) {
354 for (Block b : getPredecessors()) {
355 newPreds.add(b);
356 }
357 } else {
358 newPreds.add(curPred);
359 }
360 }
361
362 next.setPredecessors(newPreds.toArray(new Block[0]));
363 }
364
365 protected void setPostDominator(Block postdominator) {
366 this.postdominator = postdominator;
367 }
368 }