1 /*
2  * Copyright (C) 2012 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #ifndef ART_LIBDEXFILE_DEX_MODIFIERS_H_
18 #define ART_LIBDEXFILE_DEX_MODIFIERS_H_
19 
20 #include <string>
21 
22 #include <stdint.h>
23 
24 namespace art {
25 
26 static constexpr uint32_t kAccPublic =       0x0001;  // class, field, method, ic
27 static constexpr uint32_t kAccPrivate =      0x0002;  // field, method, ic
28 static constexpr uint32_t kAccProtected =    0x0004;  // field, method, ic
29 static constexpr uint32_t kAccStatic =       0x0008;  // field, method, ic
30 static constexpr uint32_t kAccFinal =        0x0010;  // class, field, method, ic
31 static constexpr uint32_t kAccSynchronized = 0x0020;  // method (only allowed on natives)
32 static constexpr uint32_t kAccSuper =        0x0020;  // class (not used in dex)
33 static constexpr uint32_t kAccVolatile =     0x0040;  // field
34 static constexpr uint32_t kAccBridge =       0x0040;  // method (1.5)
35 static constexpr uint32_t kAccTransient =    0x0080;  // field
36 static constexpr uint32_t kAccVarargs =      0x0080;  // method (1.5)
37 static constexpr uint32_t kAccNative =       0x0100;  // method
38 static constexpr uint32_t kAccInterface =    0x0200;  // class, ic
39 static constexpr uint32_t kAccAbstract =     0x0400;  // class, method, ic
40 static constexpr uint32_t kAccStrict =       0x0800;  // method
41 static constexpr uint32_t kAccSynthetic =    0x1000;  // class, field, method, ic
42 static constexpr uint32_t kAccAnnotation =   0x2000;  // class, ic (1.5)
43 static constexpr uint32_t kAccEnum =         0x4000;  // class, field, ic (1.5)
44 
45 static constexpr uint32_t kAccJavaFlagsMask = 0xffff;  // bits set from Java sources (low 16)
46 
47 static constexpr uint32_t kAccConstructor =           0x00010000;  // method (dex only) <(cl)init>
48 static constexpr uint32_t kAccDeclaredSynchronized =  0x00020000;  // method (dex only)
49 static constexpr uint32_t kAccClassIsProxy =          0x00040000;  // class  (dex only)
50 // Set to indicate that the ArtMethod is obsolete and has a different DexCache + DexFile from its
51 // declaring class. This flag may only be applied to methods.
52 static constexpr uint32_t kAccObsoleteMethod =        0x00040000;  // method (runtime)
53 // Used by a method to denote that its execution does not need to go through slow path interpreter.
54 static constexpr uint32_t kAccSkipAccessChecks =      0x00080000;  // method (runtime, not native)
55 // Used by a class to denote that the verifier has attempted to check it at least once.
56 static constexpr uint32_t kAccVerificationAttempted = 0x00080000;  // class (runtime)
57 static constexpr uint32_t kAccSkipHiddenapiChecks =   0x00100000;  // class (runtime)
58 // Used by a class to denote that this class and any objects with this as a
59 // declaring-class/super-class are to be considered obsolete, meaning they should not be used by.
60 static constexpr uint32_t kAccObsoleteObject =        0x00200000;  // class (runtime)
61 // This is set by the class linker during LinkInterfaceMethods. It is used by a method
62 // to represent that it was copied from its declaring class into another class.
63 // We need copies of the original method because the method may end up in different
64 // places in classes vtables, and the vtable index is set in ArtMethod.method_index.
65 //
66 // Default methods copied to a sub-interface or a concrete class shall have this bit set.
67 // Default conflict methods shall be marked as copied, abstract and default.
68 // Miranda methods shall be marked as copied and abstract but not default.
69 //
70 // We do not have intrinsics for any default methods and therefore intrinsics are never
71 // copied. We can therefore use a flag from the intrinsic flags range.
72 static constexpr uint32_t kAccCopied =                0x01000000;  // method (runtime)
73 static constexpr uint32_t kAccDefault =               0x00400000;  // method (runtime)
74 // Native method flags are set when linking the methods based on the presence of the
75 // @dalvik.annotation.optimization.{Fast,Critical}Native annotations with build visibility.
76 // Reuse the values of kAccSkipAccessChecks and kAccMiranda which are not used for native methods.
77 static constexpr uint32_t kAccFastNative =            0x00080000;  // method (runtime; native only)
78 static constexpr uint32_t kAccCriticalNative =        0x00100000;  // method (runtime; native only)
79 
80 // Set by the JIT when clearing profiling infos to denote that a method was previously warm.
81 static constexpr uint32_t kAccPreviouslyWarm =        0x00800000;  // method (runtime)
82 
83 // Set by the verifier for a method we do not want the compiler to compile.
84 static constexpr uint32_t kAccCompileDontBother =     0x02000000;  // method (runtime)
85 
86 // Used in conjunction with kAccCompileDontBother to mark the method as pre compiled
87 // by the JIT compiler. We are reusing the value of the kAccPreviouslyWarm flag which
88 // is meaningless for other methods with kAccCompileDontBother as we do not collect
89 // samples for such methods.
90 static constexpr uint32_t kAccPreCompiled =           0x00800000;  // method (runtime)
91 static_assert(kAccPreCompiled == kAccPreviouslyWarm);
92 
93 // Set by the verifier for a method that could not be verified to follow structured locking.
94 static constexpr uint32_t kAccMustCountLocks =        0x04000000;  // method (runtime)
95 
96 // Set by the class linker for a method that has only one implementation for a
97 // virtual call.
98 static constexpr uint32_t kAccSingleImplementation =  0x08000000;  // method (runtime)
99 
100 // Whether nterp can take a fast path when entering this method (runtime; non-native)
101 static constexpr uint32_t kAccNterpEntryPointFastPathFlag = 0x00100000;
102 // Set by the class linker to mark that a method does not have floating points
103 // or longs in its shorty.
104 static constexpr uint32_t kAccNterpInvokeFastPathFlag     = 0x00200000;  // method (runtime)
105 
106 static constexpr uint32_t kAccPublicApi =             0x10000000;  // field, method
107 static constexpr uint32_t kAccCorePlatformApi =       0x20000000;  // field, method
108 
109 // Non-intrinsics: Caches whether we can use fast-path in the interpreter invokes.
110 // Intrinsics: These bits are part of the intrinsic ordinal.
111 static constexpr uint32_t kAccFastInterpreterToInterpreterInvoke = 0x40000000;  // method.
112 
113 // Set by the compiler driver when compiling boot classes with instrinsic methods.
114 static constexpr uint32_t kAccIntrinsic  =            0x80000000;  // method (runtime)
115 
116 // Special runtime-only flags.
117 // Interface and all its super-interfaces with default methods have been recursively initialized.
118 static constexpr uint32_t kAccRecursivelyInitialized    = 0x20000000;
119 // Interface declares some default method.
120 static constexpr uint32_t kAccHasDefaultMethod          = 0x40000000;
121 // class/ancestor overrides finalize()
122 static constexpr uint32_t kAccClassIsFinalizable        = 0x80000000;
123 
124 static constexpr uint32_t kAccHiddenapiBits = kAccPublicApi | kAccCorePlatformApi;
125 
126 // Continuous sequence of bits used to hold the ordinal of an intrinsic method. Flags
127 // which overlap are not valid when kAccIntrinsic is set.
128 static constexpr uint32_t kAccIntrinsicBits = kAccHiddenapiBits |
129     kAccSingleImplementation | kAccMustCountLocks | kAccCompileDontBother | kAccCopied |
130     kAccPreviouslyWarm | kAccFastInterpreterToInterpreterInvoke;
131 
132 // Valid (meaningful) bits for a field.
133 static constexpr uint32_t kAccValidFieldFlags = kAccPublic | kAccPrivate | kAccProtected |
134     kAccStatic | kAccFinal | kAccVolatile | kAccTransient | kAccSynthetic | kAccEnum;
135 
136 // Valid (meaningful) bits for a method.
137 static constexpr uint32_t kAccValidMethodFlags = kAccPublic | kAccPrivate | kAccProtected |
138     kAccStatic | kAccFinal | kAccSynchronized | kAccBridge | kAccVarargs | kAccNative |
139     kAccAbstract | kAccStrict | kAccSynthetic | kAccConstructor | kAccDeclaredSynchronized;
140 static_assert(((kAccIntrinsic | kAccIntrinsicBits) & kAccValidMethodFlags) == 0,
141               "Intrinsic bits and valid dex file method access flags must not overlap.");
142 
143 // Valid (meaningful) bits for a class (not interface).
144 // Note 1. These are positive bits. Other bits may have to be zero.
145 // Note 2. Inner classes can expose more access flags to Java programs. That is handled by libcore.
146 static constexpr uint32_t kAccValidClassFlags = kAccPublic | kAccFinal | kAccSuper |
147     kAccAbstract | kAccSynthetic | kAccEnum;
148 
149 // Valid (meaningful) bits for an interface.
150 // Note 1. Annotations are interfaces.
151 // Note 2. These are positive bits. Other bits may have to be zero.
152 // Note 3. Inner classes can expose more access flags to Java programs. That is handled by libcore.
153 static constexpr uint32_t kAccValidInterfaceFlags = kAccPublic | kAccInterface |
154     kAccAbstract | kAccSynthetic | kAccAnnotation;
155 
156 static constexpr uint32_t kAccVisibilityFlags = kAccPublic | kAccPrivate | kAccProtected;
157 
158 // Returns a human-readable version of the Java part of the access flags, e.g., "private static "
159 // (note the trailing whitespace).
160 std::string PrettyJavaAccessFlags(uint32_t access_flags);
161 
162 }  // namespace art
163 
164 #endif  // ART_LIBDEXFILE_DEX_MODIFIERS_H_
165 
166