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
27 import org.graalvm.compiler.core.common.cfg.BlockMap;
28 import org.graalvm.compiler.core.common.cfg.Loop;
29 import org.graalvm.compiler.debug.Debug;
30 import org.graalvm.compiler.graph.Node;
31 import org.graalvm.compiler.nodes.AbstractBeginNode;
32 import org.graalvm.compiler.nodes.AbstractMergeNode;
33 import org.graalvm.compiler.nodes.LoopBeginNode;
34 import org.graalvm.compiler.nodes.PhiNode;
35 import org.graalvm.compiler.nodes.cfg.Block;
36 import org.graalvm.compiler.nodes.cfg.HIRLoop;
37 import org.graalvm.compiler.nodes.memory.FloatingReadNode;
38 import org.graalvm.compiler.nodes.memory.MemoryCheckpoint;
39 import org.graalvm.compiler.nodes.memory.MemoryNode;
40 import org.graalvm.compiler.nodes.memory.MemoryPhiNode;
41 import org.graalvm.compiler.phases.graph.ReentrantBlockIterator;
42 import org.graalvm.compiler.phases.graph.ReentrantBlockIterator.BlockIteratorClosure;
43 import org.graalvm.util.Equivalence;
44 import org.graalvm.word.LocationIdentity;
45 import org.graalvm.util.EconomicSet;
46
47 public final class MemoryScheduleVerification extends BlockIteratorClosure<EconomicSet<FloatingReadNode>> {
48
49 private final BlockMap<List<Node>> blockToNodesMap;
50
51 public static boolean check(Block startBlock, BlockMap<List<Node>> blockToNodesMap) {
52 ReentrantBlockIterator.apply(new MemoryScheduleVerification(blockToNodesMap), startBlock);
53 return true;
54 }
55
56 private MemoryScheduleVerification(BlockMap<List<Node>> blockToNodesMap) {
57 this.blockToNodesMap = blockToNodesMap;
58 }
59
60 @Override
61 protected EconomicSet<FloatingReadNode> getInitialState() {
62 return EconomicSet.create(Equivalence.IDENTITY);
63 }
64
65 @Override
66 protected EconomicSet<FloatingReadNode> processBlock(Block block, EconomicSet<FloatingReadNode> currentState) {
67 AbstractBeginNode beginNode = block.getBeginNode();
68 if (beginNode instanceof AbstractMergeNode) {
69 AbstractMergeNode abstractMergeNode = (AbstractMergeNode) beginNode;
70 for (PhiNode phi : abstractMergeNode.phis()) {
71 if (phi instanceof MemoryPhiNode) {
72 MemoryPhiNode memoryPhiNode = (MemoryPhiNode) phi;
73 addFloatingReadUsages(currentState, memoryPhiNode);
74 }
75 }
76 }
77 for (Node n : blockToNodesMap.get(block)) {
78 if (n instanceof MemoryCheckpoint) {
79 if (n instanceof MemoryCheckpoint.Single) {
80 MemoryCheckpoint.Single single = (MemoryCheckpoint.Single) n;
81 processLocation(n, single.getLocationIdentity(), currentState);
82 } else if (n instanceof MemoryCheckpoint.Multi) {
83 MemoryCheckpoint.Multi multi = (MemoryCheckpoint.Multi) n;
84 for (LocationIdentity location : multi.getLocationIdentities()) {
85 processLocation(n, location, currentState);
86 }
87 }
88
89 addFloatingReadUsages(currentState, n);
90 } else if (n instanceof MemoryNode) {
91 addFloatingReadUsages(currentState, n);
92 } else if (n instanceof FloatingReadNode) {
93 FloatingReadNode floatingReadNode = (FloatingReadNode) n;
94 if (floatingReadNode.getLastLocationAccess() != null && floatingReadNode.getLocationIdentity().isMutable()) {
95 if (currentState.contains(floatingReadNode)) {
96 // Floating read was found in the state.
97 currentState.remove(floatingReadNode);
98 } else {
99 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=" +
100 block + ", block begin: " + block.getBeginNode() + " block loop: " + block.getLoop() + ", " + blockToNodesMap.get(block).get(0));
101 }
102 }
103
104 }
105 }
106 return currentState;
107 }
108
109 private static void addFloatingReadUsages(EconomicSet<FloatingReadNode> currentState, Node n) {
110 for (FloatingReadNode read : n.usages().filter(FloatingReadNode.class)) {
111 if (read.getLastLocationAccess() == n && read.getLocationIdentity().isMutable()) {
112 currentState.add(read);
113 }
114 }
115 }
116
117 private void processLocation(Node n, LocationIdentity location, EconomicSet<FloatingReadNode> currentState) {
118 assert n != null;
119 if (location.isImmutable()) {
120 return;
121 }
122
123 for (FloatingReadNode r : cloneState(currentState)) {
124 if (r.getLocationIdentity().overlaps(location)) {
125 // This read is killed by this location.
126 Debug.log(Debug.VERBOSE_LEVEL, "%s removing %s from state", n, r);
127 currentState.remove(r);
128 }
129 }
130 }
131
132 @Override
133 protected EconomicSet<FloatingReadNode> merge(Block merge, List<EconomicSet<FloatingReadNode>> states) {
134 EconomicSet<FloatingReadNode> result = states.get(0);
135 for (int i = 1; i < states.size(); ++i) {
136 result.retainAll(states.get(i));
137 }
138 return result;
139 }
140
141 @Override
142 protected EconomicSet<FloatingReadNode> cloneState(EconomicSet<FloatingReadNode> oldState) {
143 EconomicSet<FloatingReadNode> result = EconomicSet.create(Equivalence.IDENTITY);
144 if (oldState != null) {
145 result.addAll(oldState);
146 }
147 return result;
148 }
149
150 @Override
151 protected List<EconomicSet<FloatingReadNode>> processLoop(Loop<Block> loop, EconomicSet<FloatingReadNode> initialState) {
152 HIRLoop l = (HIRLoop) loop;
153 for (MemoryPhiNode memoryPhi : ((LoopBeginNode) l.getHeader().getBeginNode()).memoryPhis()) {
154 for (FloatingReadNode r : cloneState(initialState)) {
155 if (r.getLocationIdentity().overlaps(memoryPhi.getLocationIdentity())) {
156 initialState.remove(r);
157 }
158 }
159 }
160 return ReentrantBlockIterator.processLoop(this, loop, initialState).exitStates;
161 }
162 }