1 /*
2  * Copyright (c) 2012, 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
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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
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22  */
23 package jdk.vm.ci.meta;
24 
25 import java.lang.reflect.Constructor;
26 import java.lang.reflect.Executable;
27 import java.lang.reflect.Field;
28 import java.lang.reflect.Method;
29 
30 import jdk.vm.ci.meta.SpeculationLog.Speculation;
31 
32 /**
33  * Provides access to the metadata of a class typically provided in a class file.
34  */
35 public interface MetaAccessProvider {
36 
37     /**
38      * Returns the resolved Java type representing a given Java class.
39      *
40      * @param clazz the Java class object
41      * @return the resolved Java type object
42      */
lookupJavaType(Class<?> clazz)43     ResolvedJavaType lookupJavaType(Class<?> clazz);
44 
45     /**
46      * Returns the resolved Java types representing some given Java classes.
47      *
48      * @param classes the Java class objects
49      * @return the resolved Java type objects
50      */
lookupJavaTypes(Class<?>[] classes)51     default ResolvedJavaType[] lookupJavaTypes(Class<?>[] classes) {
52         ResolvedJavaType[] result = new ResolvedJavaType[classes.length];
53         for (int i = 0; i < result.length; i++) {
54             result[i] = lookupJavaType(classes[i]);
55         }
56         return result;
57     }
58 
59     /**
60      * Provides the {@link ResolvedJavaMethod} for a {@link Method} or {@link Constructor} obtained
61      * via reflection.
62      */
lookupJavaMethod(Executable reflectionMethod)63     ResolvedJavaMethod lookupJavaMethod(Executable reflectionMethod);
64 
65     /**
66      * Provides the {@link ResolvedJavaField} for a {@link Field} obtained via reflection.
67      */
lookupJavaField(Field reflectionField)68     ResolvedJavaField lookupJavaField(Field reflectionField);
69 
70     /**
71      * Returns the resolved Java type of the given {@link JavaConstant} object.
72      *
73      * @return {@code null} if {@code constant.isNull() || !constant.kind.isObject()}
74      */
lookupJavaType(JavaConstant constant)75     ResolvedJavaType lookupJavaType(JavaConstant constant);
76 
77     /**
78      * Returns the number of bytes occupied by this constant value or constant object.
79      *
80      * @param constant the constant whose bytes should be measured
81      * @return the number of bytes occupied by this constant
82      */
getMemorySize(JavaConstant constant)83     long getMemorySize(JavaConstant constant);
84 
85     /**
86      * Parses a
87      * <a href="http://docs.oracle.com/javase/specs/jvms/se7/html/jvms-4.html#jvms-4.3.3">method
88      * descriptor</a> into a {@link Signature}.
89      *
90      * @throws IllegalArgumentException if the method descriptor is not well formed
91      */
parseMethodDescriptor(String methodDescriptor)92     Signature parseMethodDescriptor(String methodDescriptor);
93 
94     /**
95      * Encodes a deoptimization action and a deoptimization reason in an integer value.
96      *
97      * @param debugId an integer that can be used to track the origin of a deoptimization at
98      *            runtime. There is no guarantee that the runtime will use this value. The runtime
99      *            may even keep fewer than 32 bits.
100      *
101      * @return the encoded value as an integer
102      */
encodeDeoptActionAndReason(DeoptimizationAction action, DeoptimizationReason reason, int debugId)103     JavaConstant encodeDeoptActionAndReason(DeoptimizationAction action, DeoptimizationReason reason, int debugId);
104 
105     /**
106      * Gets a constant that denotes {@code speculation}. The constant can passed to the
107      * deoptimization handler (e.g., through a thread local) to indicate a failed speculation.
108      */
encodeSpeculation(Speculation speculation)109     JavaConstant encodeSpeculation(Speculation speculation);
110 
111     /**
112      * Decodes {@code constant} back to a {@link Speculation} object.
113      *
114      * @throws IllegalArgumentException if {@code constant} can only be decoded through a
115      *             {@link SpeculationLog} and {@code speculationLog} does not contain the
116      *             speculation denoted by {@code constant}
117      */
decodeSpeculation(JavaConstant constant, SpeculationLog speculationLog)118     Speculation decodeSpeculation(JavaConstant constant, SpeculationLog speculationLog);
119 
decodeDeoptReason(JavaConstant constant)120     DeoptimizationReason decodeDeoptReason(JavaConstant constant);
121 
decodeDeoptAction(JavaConstant constant)122     DeoptimizationAction decodeDeoptAction(JavaConstant constant);
123 
decodeDebugId(JavaConstant constant)124     int decodeDebugId(JavaConstant constant);
125 
getArrayBaseOffset(JavaKind elementKind)126     int getArrayBaseOffset(JavaKind elementKind);
127 
getArrayIndexScale(JavaKind elementKind)128     int getArrayIndexScale(JavaKind elementKind);
129 }
130