1 /*
2 * Copyright (c) 2011, 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 package jdk.vm.ci.hotspot;
24
25 import jdk.vm.ci.meta.JavaMethodProfile;
26 import jdk.vm.ci.meta.JavaTypeProfile;
27 import jdk.vm.ci.meta.ProfilingInfo;
28 import jdk.vm.ci.meta.TriState;
29
30 /**
31 * Base class for accessing the different kinds of data in a HotSpot {@code MethodData}. This is
32 * similar to {@link ProfilingInfo}, but most methods require a {@link HotSpotMethodData} and the
33 * exact position within the method data.
34 */
35 abstract class HotSpotMethodDataAccessor {
36
37 final int tag;
38 final int staticSize;
39 final HotSpotMethodData.VMState state;
40 final HotSpotVMConfig config;
41
42 protected HotSpotMethodDataAccessor(HotSpotMethodData.VMState state, int tag, int staticSize) {
43 this.state = state;
44 this.config = state.config;
45 this.tag = tag;
46 this.staticSize = staticSize;
47 }
48
49 /**
50 * Returns the tag stored in the LayoutData header.
51 *
52 * @return tag stored in the LayoutData header
53 */
54 int getTag() {
55 return tag;
56 }
57
58 static int readTag(HotSpotVMConfig config, HotSpotMethodData data, int position) {
59 final int tag = data.readUnsignedByte(position, config.dataLayoutTagOffset);
60 assert tag >= config.dataLayoutNoTag && tag <= config.dataLayoutSpeculativeTrapDataTag : "profile data tag out of bounds: " + tag;
61 return tag;
62 }
63
64 /**
65 * Returns the BCI stored in the LayoutData header.
66 *
67 * @return an integer between 0 and {@link Short#MAX_VALUE} inclusive, or -1 if not supported
68 */
69 int getBCI(HotSpotMethodData data, int position) {
70 return data.readUnsignedShort(position, config.dataLayoutBCIOffset);
71 }
72
73 /**
74 * Computes the size for the specific data at the given position.
75 *
76 * @return a value greater than 0
77 */
78 final int getSize(HotSpotMethodData data, int position) {
79 int size = staticSize + getDynamicSize(data, position);
80 // Sanity check against VM
81 int vmSize = HotSpotJVMCIRuntime.runtime().compilerToVm.methodDataProfileDataSize(data.methodDataPointer, position);
82 assert size == vmSize : size + " != " + vmSize;
83 return size;
84 }
85
86 TriState getExceptionSeen(HotSpotMethodData data, int position) {
87 final int exceptionsMask = 1 << config.bitDataExceptionSeenFlag;
88 return TriState.get((getFlags(data, position) & exceptionsMask) != 0);
89 }
90
91 /**
92 * @param data
93 * @param position
94 */
95 JavaTypeProfile getTypeProfile(HotSpotMethodData data, int position) {
96 return null;
97 }
98
99 /**
100 * @param data
101 * @param position
102 */
103 JavaMethodProfile getMethodProfile(HotSpotMethodData data, int position) {
104 return null;
105 }
106
107 /**
108 * @param data
109 * @param position
110 */
111 double getBranchTakenProbability(HotSpotMethodData data, int position) {
112 return -1;
113 }
114
115 /**
116 * @param data
117 * @param position
118 */
119 double[] getSwitchProbabilities(HotSpotMethodData data, int position) {
120 return null;
121 }
122
123 /**
124 * @param data
125 * @param position
126 */
127 int getExecutionCount(HotSpotMethodData data, int position) {
128 return -1;
129 }
130
131 /**
132 * @param data
133 * @param position
134 */
135 TriState getNullSeen(HotSpotMethodData data, int position) {
136 return TriState.UNKNOWN;
137 }
138
139 protected int getFlags(HotSpotMethodData data, int position) {
140 return data.readUnsignedByte(position, config.dataLayoutFlagsOffset);
141 }
142
143 /**
144 * @param data
145 * @param position
146 */
147 protected int getDynamicSize(HotSpotMethodData data, int position) {
148 return 0;
149 }
150
151 abstract StringBuilder appendTo(StringBuilder sb, HotSpotMethodData data, int pos);
152
153 }