1 /*
2 * Copyright (c) 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.phases.contract;
26
27 import java.util.ArrayList;
28 import java.util.List;
29 import java.util.function.Function;
30
31 import org.graalvm.compiler.core.common.cfg.BlockMap;
32 import org.graalvm.compiler.debug.CounterKey;
33 import org.graalvm.compiler.debug.DebugContext;
34 import org.graalvm.compiler.graph.Node;
35 import org.graalvm.compiler.graph.VerificationError;
36 import org.graalvm.compiler.nodes.FixedNode;
37 import org.graalvm.compiler.nodes.StructuredGraph;
38 import org.graalvm.compiler.nodes.cfg.Block;
39 import org.graalvm.compiler.nodes.cfg.ControlFlowGraph;
40 import org.graalvm.compiler.phases.schedule.SchedulePhase;
41
42 import jdk.vm.ci.meta.ResolvedJavaMethod;
43
44 public class NodeCostUtil {
45
46 private static final CounterKey sizeComputationCount = DebugContext.counter("GraphCostComputationCount_Size");
47 private static final CounterKey sizeVerificationCount = DebugContext.counter("GraphCostVerificationCount_Size");
48
49 @SuppressWarnings("try")
50 public static int computeGraphSize(StructuredGraph graph) {
51 sizeComputationCount.increment(graph.getDebug());
52 int size = 0;
53 for (Node n : graph.getNodes()) {
54 size += n.estimatedNodeSize().value;
55 }
56 assert size >= 0;
57 return size;
58 }
59
60 @SuppressWarnings("try")
61 public static double computeGraphCycles(StructuredGraph graph, boolean fullSchedule) {
62 Function<Block, Iterable<? extends Node>> blockToNodes;
63 ControlFlowGraph cfg;
64 if (fullSchedule) {
65 SchedulePhase schedule = new SchedulePhase(SchedulePhase.SchedulingStrategy.LATEST_OUT_OF_LOOPS, true);
66 schedule.apply(graph);
67 cfg = graph.getLastSchedule().getCFG();
68 blockToNodes = b -> graph.getLastSchedule().getBlockToNodesMap().get(b);
69 } else {
70 cfg = ControlFlowGraph.compute(graph, true, true, false, false);
71 BlockMap<List<FixedNode>> nodes = new BlockMap<>(cfg);
72 for (Block b : cfg.getBlocks()) {
73 ArrayList<FixedNode> curNodes = new ArrayList<>();
74 for (FixedNode node : b.getNodes()) {
75 curNodes.add(node);
76 }
77 nodes.put(b, curNodes);
78 }
79 blockToNodes = b -> nodes.get(b);
80 }
81 double weightedCycles = 0D;
82 DebugContext debug = graph.getDebug();
83 try (DebugContext.Scope s = debug.scope("NodeCostSummary")) {
84 for (Block block : cfg.getBlocks()) {
85 for (Node n : blockToNodes.apply(block)) {
86 double probWeighted = n.estimatedNodeCycles().value * block.getRelativeFrequency();
87 assert Double.isFinite(probWeighted);
88 weightedCycles += probWeighted;
89 if (debug.isLogEnabled()) {
90 debug.log("Node %s contributes cycles:%f size:%d to graph %s [block freq:%f]", n, n.estimatedNodeCycles().value * block.getRelativeFrequency(),
91 n.estimatedNodeSize().value, graph, block.getRelativeFrequency());
92 }
93 }
94 }
95 }
96 assert weightedCycles >= 0D;
97 assert Double.isFinite(weightedCycles);
98 return weightedCycles;
99 }
100
101 private static int deltaCompare(double a, double b, double delta) {
102 if (Math.abs(a - b) <= delta) {
103 return 0;
104 }
105 return Double.compare(a, b);
106 }
107
108 /**
109 * Factor to control the "imprecision" of the before - after relation when verifying phase
110 * effects. If the cost model is perfect the best theoretical value is 0.0D (Ignoring the fact
111 * that profiling information is not reliable and thus the, probability based, profiling view on
112 * a graph is different than the reality).
113 */
114 private static final double DELTA = 0.001D;
115
116 public static void phaseFulfillsSizeContract(StructuredGraph graph, int codeSizeBefore, int codeSizeAfter, PhaseSizeContract contract) {
117 sizeVerificationCount.increment(graph.getDebug());
118 final double codeSizeIncrease = contract.codeSizeIncrease();
119 final double graphSizeDelta = codeSizeBefore * DELTA;
120 if (deltaCompare(codeSizeAfter, codeSizeBefore * codeSizeIncrease, graphSizeDelta) > 0) {
121 ResolvedJavaMethod method = graph.method();
122 double increase = (double) codeSizeAfter / (double) codeSizeBefore;
123 throw new VerificationError("Phase %s expects to increase code size by at most a factor of %.2f but an increase of %.2f was seen (code size before: %d, after: %d)%s",
124 contract.contractorName(), codeSizeIncrease, increase, codeSizeBefore, codeSizeAfter,
125 method != null ? " when compiling method " + method.format("%H.%n(%p)") + "." : ".");
126 }
127 }
128
129 }