1 /*
2 * Copyright (c) 2015, 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.phases.schedule;
24
25 import java.util.List;
26 import java.util.Set;
27
28 import org.graalvm.compiler.core.common.CollectionsFactory;
29 import org.graalvm.compiler.core.common.LocationIdentity;
30 import org.graalvm.compiler.core.common.cfg.BlockMap;
31 import org.graalvm.compiler.core.common.cfg.Loop;
32 import org.graalvm.compiler.graph.Node;
33 import org.graalvm.compiler.nodes.AbstractBeginNode;
34 import org.graalvm.compiler.nodes.AbstractMergeNode;
35 import org.graalvm.compiler.nodes.LoopBeginNode;
36 import org.graalvm.compiler.nodes.PhiNode;
37 import org.graalvm.compiler.nodes.cfg.Block;
38 import org.graalvm.compiler.nodes.cfg.HIRLoop;
39 import org.graalvm.compiler.nodes.memory.FloatingReadNode;
40 import org.graalvm.compiler.nodes.memory.MemoryCheckpoint;
41 import org.graalvm.compiler.nodes.memory.MemoryNode;
42 import org.graalvm.compiler.nodes.memory.MemoryPhiNode;
43 import org.graalvm.compiler.phases.graph.ReentrantBlockIterator;
44 import org.graalvm.compiler.phases.graph.ReentrantBlockIterator.BlockIteratorClosure;
45
46 public final class MemoryScheduleVerification extends BlockIteratorClosure<Set<FloatingReadNode>> {
47
48 private final BlockMap<List<Node>> blockToNodesMap;
49
50 public static boolean check(Block startBlock, BlockMap<List<Node>> blockToNodesMap) {
51 ReentrantBlockIterator.apply(new MemoryScheduleVerification(blockToNodesMap), startBlock);
52 return true;
53 }
54
55 private MemoryScheduleVerification(BlockMap<List<Node>> blockToNodesMap) {
56 this.blockToNodesMap = blockToNodesMap;
57 }
58
59 @Override
60 protected Set<FloatingReadNode> getInitialState() {
61 return CollectionsFactory.newSet();
62 }
63
64 @Override
65 protected Set<FloatingReadNode> processBlock(Block block, Set<FloatingReadNode> currentState) {
66 AbstractBeginNode beginNode = block.getBeginNode();
67 if (beginNode instanceof AbstractMergeNode) {
68 AbstractMergeNode abstractMergeNode = (AbstractMergeNode) beginNode;
69 for (PhiNode phi : abstractMergeNode.phis()) {
70 if (phi instanceof MemoryPhiNode) {
71 MemoryPhiNode memoryPhiNode = (MemoryPhiNode) phi;
72 addFloatingReadUsages(currentState, memoryPhiNode);
73 }
74 }
75 }
76 for (Node n : blockToNodesMap.get(block)) {
77 if (n instanceof MemoryCheckpoint) {
78 if (n instanceof MemoryCheckpoint.Single) {
79 MemoryCheckpoint.Single single = (MemoryCheckpoint.Single) n;
80 processLocation(n, single.getLocationIdentity(), currentState);
81 } else if (n instanceof MemoryCheckpoint.Multi) {
82 MemoryCheckpoint.Multi multi = (MemoryCheckpoint.Multi) n;
83 for (LocationIdentity location : multi.getLocationIdentities()) {
84 processLocation(n, location, currentState);
85 }
86 }
87
88 addFloatingReadUsages(currentState, n);
89 } else if (n instanceof MemoryNode) {
90 addFloatingReadUsages(currentState, n);
91 } else if (n instanceof FloatingReadNode) {
92 FloatingReadNode floatingReadNode = (FloatingReadNode) n;
93 if (floatingReadNode.getLastLocationAccess() != null && floatingReadNode.getLocationIdentity().isMutable()) {
94 if (currentState.contains(floatingReadNode)) {
95 // Floating read was found in the state.
96 currentState.remove(floatingReadNode);
97 } else {
98 throw new RuntimeException("Floating read node " + n + " was not found in the state, i.e., it was killed by a memory check point before its place in the schedule. Block=" +
99 block + ", block begin: " + block.getBeginNode() + " block loop: " + block.getLoop() + ", " + blockToNodesMap.get(block).get(0));
100 }
101 }
102
103 }
104 }
105 return currentState;
106 }
107
108 private static void addFloatingReadUsages(Set<FloatingReadNode> currentState, Node n) {
109 for (FloatingReadNode read : n.usages().filter(FloatingReadNode.class)) {
110 if (read.getLastLocationAccess() == n && read.getLocationIdentity().isMutable()) {
111 currentState.add(read);
112 }
113 }
114 }
115
116 private void processLocation(Node n, LocationIdentity location, Set<FloatingReadNode> currentState) {
117 assert n != null;
118 if (location.isImmutable()) {
119 return;
120 }
121
122 for (FloatingReadNode r : cloneState(currentState)) {
123 if (r.getLocationIdentity().overlaps(location)) {
124 // This read is killed by this location.
125 currentState.remove(r);
126 }
127 }
128 }
129
130 @Override
131 protected Set<FloatingReadNode> merge(Block merge, List<Set<FloatingReadNode>> states) {
132 Set<FloatingReadNode> result = states.get(0);
133 for (int i = 1; i < states.size(); ++i) {
134 result.retainAll(states.get(i));
135 }
136 return result;
137 }
138
139 @Override
140 protected Set<FloatingReadNode> cloneState(Set<FloatingReadNode> oldState) {
141 Set<FloatingReadNode> result = CollectionsFactory.newSet();
142 if (oldState != null) {
143 result.addAll(oldState);
144 }
145 return result;
146 }
147
148 @Override
149 protected List<Set<FloatingReadNode>> processLoop(Loop<Block> loop, Set<FloatingReadNode> initialState) {
150 HIRLoop l = (HIRLoop) loop;
151 for (MemoryPhiNode memoryPhi : ((LoopBeginNode) l.getHeader().getBeginNode()).phis().filter(MemoryPhiNode.class)) {
152 for (FloatingReadNode r : cloneState(initialState)) {
153 if (r.getLocationIdentity().overlaps(memoryPhi.getLocationIdentity())) {
154 initialState.remove(r);
155 }
156 }
157 }
158 return ReentrantBlockIterator.processLoop(this, loop, initialState).exitStates;
159 }
160 }