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 package org.graalvm.compiler.phases.contract;
24
25 import java.util.ArrayList;
26 import java.util.List;
27 import java.util.function.Function;
28
29 import org.graalvm.compiler.core.common.cfg.BlockMap;
30 import org.graalvm.compiler.debug.Debug;
31 import org.graalvm.compiler.debug.DebugCounter;
32 import org.graalvm.compiler.graph.Node;
33 import org.graalvm.compiler.graph.VerificationError;
34 import org.graalvm.compiler.nodes.FixedNode;
35 import org.graalvm.compiler.nodes.StructuredGraph;
36 import org.graalvm.compiler.nodes.cfg.Block;
37 import org.graalvm.compiler.nodes.cfg.ControlFlowGraph;
38 import org.graalvm.compiler.phases.schedule.SchedulePhase;
39
40 import jdk.vm.ci.meta.ResolvedJavaMethod;
41
42 public class NodeCostUtil {
43
44 private static final DebugCounter sizeComputationCount = Debug.counter("GraphCostComputationCount_Size");
45 private static final DebugCounter sizeVerificationCount = Debug.counter("GraphCostVerificationCount_Size");
46
47 @SuppressWarnings("try")
48 public static int computeGraphSize(StructuredGraph graph) {
49 sizeComputationCount.increment();
50 int size = 0;
51 for (Node n : graph.getNodes()) {
52 size += n.estimatedNodeSize().value;
53 }
54 assert size >= 0;
55 return size;
56 }
57
58 @SuppressWarnings("try")
59 public static double computeGraphCycles(StructuredGraph graph, boolean fullSchedule) {
60 Function<Block, Iterable<? extends Node>> blockToNodes;
61 ControlFlowGraph cfg;
62 if (fullSchedule) {
63 SchedulePhase schedule = new SchedulePhase(SchedulePhase.SchedulingStrategy.LATEST_OUT_OF_LOOPS, true);
64 schedule.apply(graph);
65 cfg = graph.getLastSchedule().getCFG();
66 blockToNodes = b -> graph.getLastSchedule().getBlockToNodesMap().get(b);
67 } else {
68 cfg = ControlFlowGraph.compute(graph, true, true, false, false);
69 BlockMap<List<FixedNode>> nodes = new BlockMap<>(cfg);
70 for (Block b : cfg.getBlocks()) {
71 ArrayList<FixedNode> curNodes = new ArrayList<>();
72 for (FixedNode node : b.getNodes()) {
73 curNodes.add(node);
74 }
75 nodes.put(b, curNodes);
76 }
77 blockToNodes = b -> nodes.get(b);
78 }
79 double weightedCycles = 0D;
80 try (Debug.Scope s = Debug.scope("NodeCostSummary")) {
81 for (Block block : cfg.getBlocks()) {
82 for (Node n : blockToNodes.apply(block)) {
83 double probWeighted = n.estimatedNodeCycles().value * block.probability();
84 assert Double.isFinite(probWeighted);
85 weightedCycles += probWeighted;
86 if (Debug.isLogEnabled()) {
87 Debug.log("Node %s contributes cycles:%f size:%d to graph %s [block prob:%f]", n, n.estimatedNodeCycles().value * block.probability(),
88 n.estimatedNodeSize().value, graph, block.probability());
89 }
90 }
91 }
92 }
93 assert weightedCycles >= 0D;
94 assert Double.isFinite(weightedCycles);
95 return weightedCycles;
96 }
97
98 private static int deltaCompare(double a, double b, double delta) {
99 if (Math.abs(a - b) <= delta) {
100 return 0;
101 }
102 return Double.compare(a, b);
103 }
104
105 /**
106 * Factor to control the "imprecision" of the before - after relation when verifying phase
107 * effects. If the cost model is perfect the best theoretical value is 0.0D (Ignoring the fact
108 * that profiling information is not reliable and thus the, probability based, profiling view on
109 * a graph is different than the reality).
110 */
111 private static final double DELTA = 0.001D;
112
113 public static void phaseFulfillsSizeContract(StructuredGraph graph, int codeSizeBefore, int codeSizeAfter, PhaseSizeContract contract) {
114 sizeVerificationCount.increment();
115 final double codeSizeIncrease = contract.codeSizeIncrease();
116 final double graphSizeDelta = codeSizeBefore * DELTA;
117 if (deltaCompare(codeSizeAfter, codeSizeBefore * codeSizeIncrease, graphSizeDelta) > 0) {
118 ResolvedJavaMethod method = graph.method();
119 double increase = (double) codeSizeAfter / (double) codeSizeBefore;
120 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",
121 contract.contractorName(), codeSizeIncrease, increase, codeSizeBefore, codeSizeAfter,
122 method != null ? " when compiling method " + method.format("%H.%n(%p)") + "." : ".");
123 }
124 }
125
126 }