1 /*
2 * Copyright (c) 2009, 2025, 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. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package com.sun.tools.javap;
27
28 import java.lang.classfile.constantpool.NameAndTypeEntry;
29 import java.util.HashMap;
30 import java.util.List;
31 import java.util.Map;
32 import java.lang.classfile.Attributes;
33 import java.lang.classfile.ClassFile;
34
35 import java.lang.classfile.Instruction;
36 import java.lang.classfile.attribute.CodeAttribute;
37 import java.lang.classfile.attribute.StackMapFrameInfo;
38 import java.lang.classfile.attribute.StackMapTableAttribute;
39
40 /**
41 * Annotate instructions with stack map.
42 *
43 * <p><b>This is NOT part of any supported API.
44 * If you write code that depends on this, you do so at your own risk.
45 * This code and its internal interfaces are subject to change or
46 * deletion without notice.</b>
47 */
48 public class StackMapWriter extends InstructionDetailWriter {
49 static StackMapWriter instance(Context context) {
50 StackMapWriter instance = context.get(StackMapWriter.class);
51 if (instance == null)
52 instance = new StackMapWriter(context);
53 return instance;
54 }
55
56 protected StackMapWriter(Context context) {
57 super(context);
58 context.put(StackMapWriter.class, this);
59 }
60
61 public void reset(CodeAttribute code) {
62 setStackMap(code);
63 }
64
65 void setStackMap(CodeAttribute code) {
66 StackMapTableAttribute attr = code.findAttribute(Attributes.stackMapTable())
67 .orElse(null);
68 if (attr == null) {
69 map = null;
70 return;
71 }
72 var m = code.parent().get();
73 if ((m.flags().flagsMask() & ClassFile.ACC_STATIC) == 0) {
74 thisClassName = m.parent().get().thisClass().asInternalName();
75 } else {
76 thisClassName = null;
77 }
78
79 map = new HashMap<>();
80 this.code = code;
81 for (var fr : attr.entries())
82 map.put(code.labelToBci(fr.target()), fr);
83 }
84
85 public void writeInitialDetails() {
86 writeDetails(-1);
87 }
88
89 @Override
90 public void writeDetails(int pc, Instruction instr) {
91 writeDetails(pc);
92 }
93
94 private void writeDetails(int pc) {
95 if (map == null)
96 return;
97
98 var m = map.get(pc);
99 if (m != null) {
100 print("StackMap locals: ", m.locals(), true);
101 print("StackMap stack: ", m.stack(), false);
102 if (!m.unsetFields().isEmpty()) {
103 printFields("StackMap unset fields: ", m.unsetFields());
104 }
105 }
106
107 }
108
109 void printFields(String label, List<NameAndTypeEntry> entries) {
110 print(label);
111 boolean first = true;
112 for (var e : entries) {
113 if (!first) {
114 print(", ");
115 } else {
116 first = false;
117 }
118 print(e::name);
119 print(":");
120 print(e::type);
121 }
122 println();
123 }
124
125 void print(String label, List<StackMapFrameInfo.VerificationTypeInfo> entries,
126 boolean firstThis) {
127 print(label);
128 for (var e : entries) {
129 print(" ");
130 print(e, firstThis);
131 firstThis = false;
132 }
133 println();
134 }
135
136 void print(StackMapFrameInfo.VerificationTypeInfo entry, boolean firstThis) {
137 if (entry == null) {
138 print("ERROR");
139 return;
140 }
141
142 switch (entry) {
143 case StackMapFrameInfo.SimpleVerificationTypeInfo s -> {
144 switch (s) {
145 case TOP ->
146 print("top");
147
148 case INTEGER ->
149 print("int");
150
151 case FLOAT ->
152 print("float");
153
154 case LONG ->
155 print("long");
156
157 case DOUBLE ->
158 print("double");
159
160 case NULL ->
161 print("null");
162
163 case UNINITIALIZED_THIS ->
164 print("uninit_this");
165 }
166 }
167
168 case StackMapFrameInfo.ObjectVerificationTypeInfo o -> {
169 String cln = o.className().asInternalName();
170 print(firstThis && cln.equals(thisClassName) ? "this" : cln);
171 }
172
173 case StackMapFrameInfo.UninitializedVerificationTypeInfo u ->
174 print(code.labelToBci(u.newTarget()));
175 }
176
177 }
178
179 private Map<Integer, StackMapFrameInfo> map;
180 private String thisClassName;
181 private CodeAttribute code;
182 }