2 * Copyright (C) 2008 The Android Open Source Project
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
8 * http://www.apache.org/licenses/LICENSE-2.0
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.
18 * Dalvik bytecode verifier.
20 #ifndef _DALVIK_CODEVERIFY
21 #define _DALVIK_CODEVERIFY
23 #include "analysis/VerifySubs.h"
27 * Enumeration for register type values. The "hi" piece of a 64-bit value
28 * MUST immediately follow the "lo" piece in the enumeration, so we can check
31 * Assignment of constants:
32 * [-MAXINT,-32768) : integer
33 * [-32768,-128) : short
38 * [128,32768) : posshort
39 * [32768,65536) : char
40 * [65536,MAXINT] : integer
42 * Allowed "implicit" widening conversions:
43 * zero -> boolean, posbyte, byte, posshort, short, char, integer, ref (null)
44 * one -> boolean, posbyte, byte, posshort, short, char, integer
45 * boolean -> posbyte, byte, posshort, short, char, integer
46 * posbyte -> posshort, short, integer, char
47 * byte -> short, integer
48 * posshort -> integer, char
52 * In addition, all of the above can convert to "float".
54 * We're more careful with integer values than the spec requires. The
55 * motivation is to restrict byte/char/short to the correct range of values.
56 * For example, if a method takes a byte argument, we don't want to allow
57 * the code to load the constant "1024" and pass it in.
60 kRegTypeUnknown = 0, /* initial state; use value=0 so calloc works */
61 kRegTypeUninit = 1, /* MUST be odd to distinguish from pointer */
62 kRegTypeConflict, /* merge clash makes this reg's type unknowable */
65 * Category-1nr types. The order of these is chiseled into a couple
66 * of tables, so don't add, remove, or reorder if you can avoid it.
68 #define kRegType1nrSTART kRegTypeFloat
70 kRegTypeZero, /* 32-bit 0, could be Boolean, Int, Float, or Ref */
71 kRegTypeOne, /* 32-bit 1, could be Boolean, Int, Float */
72 kRegTypeBoolean, /* must be 0 or 1 */
73 kRegTypePosByte, /* byte, known positive (can become char) */
75 kRegTypePosShort, /* short, known positive (can become char) */
79 #define kRegType1nrEND kRegTypeInteger
81 kRegTypeLongLo, /* lower-numbered register; endian-independent */
87 * Enumeration max; this is used with "full" (32-bit) RegType values.
89 * Anything larger than this is a ClassObject or uninit ref. Mask off
90 * all but the low 8 bits; if you're left with kRegTypeUninit, pull
91 * the uninit index out of the high 24. Because kRegTypeUninit has an
92 * odd value, there is no risk of a particular ClassObject pointer bit
93 * pattern being confused for it (assuming our class object allocator
94 * uses word alignment).
98 #define kRegTypeUninitMask 0xff
99 #define kRegTypeUninitShift 8
102 * RegType holds information about the type of data held in a register.
103 * For most types it's a simple enum. For reference types it holds a
104 * pointer to the ClassObject, and for uninitialized references it holds
105 * an index into the UninitInstanceMap.
109 /* table with merge logic for primitive types */
110 extern const char gDvmMergeTab[kRegTypeMAX][kRegTypeMAX];
114 * Returns "true" if the flags indicate that this address holds the start
117 INLINE bool dvmInsnIsOpcode(const InsnFlags* insnFlags, int addr) {
118 return (insnFlags[addr] & kInsnFlagWidthMask) != 0;
122 * Extract the unsigned 16-bit instruction width from "flags".
124 INLINE int dvmInsnGetWidth(const InsnFlags* insnFlags, int addr) {
125 return insnFlags[addr] & kInsnFlagWidthMask;
131 INLINE bool dvmInsnIsChanged(const InsnFlags* insnFlags, int addr) {
132 return (insnFlags[addr] & kInsnFlagChanged) != 0;
134 INLINE void dvmInsnSetChanged(InsnFlags* insnFlags, int addr, bool changed)
137 insnFlags[addr] |= kInsnFlagChanged;
139 insnFlags[addr] &= ~kInsnFlagChanged;
145 INLINE bool dvmInsnIsVisited(const InsnFlags* insnFlags, int addr) {
146 return (insnFlags[addr] & kInsnFlagVisited) != 0;
148 INLINE void dvmInsnSetVisited(InsnFlags* insnFlags, int addr, bool changed)
151 insnFlags[addr] |= kInsnFlagVisited;
153 insnFlags[addr] &= ~kInsnFlagVisited;
157 * Visited or changed?
159 INLINE bool dvmInsnIsVisitedOrChanged(const InsnFlags* insnFlags, int addr) {
160 return (insnFlags[addr] & (kInsnFlagVisited|kInsnFlagChanged)) != 0;
166 INLINE bool dvmInsnIsInTry(const InsnFlags* insnFlags, int addr) {
167 return (insnFlags[addr] & kInsnFlagInTry) != 0;
169 INLINE void dvmInsnSetInTry(InsnFlags* insnFlags, int addr, bool inTry)
173 insnFlags[addr] |= kInsnFlagInTry;
175 // insnFlags[addr] &= ~kInsnFlagInTry;
179 * Instruction is a branch target or exception handler?
181 INLINE bool dvmInsnIsBranchTarget(const InsnFlags* insnFlags, int addr) {
182 return (insnFlags[addr] & kInsnFlagBranchTarget) != 0;
184 INLINE void dvmInsnSetBranchTarget(InsnFlags* insnFlags, int addr,
189 insnFlags[addr] |= kInsnFlagBranchTarget;
191 // insnFlags[addr] &= ~kInsnFlagBranchTarget;
195 * Instruction is a GC point?
197 INLINE bool dvmInsnIsGcPoint(const InsnFlags* insnFlags, int addr) {
198 return (insnFlags[addr] & kInsnFlagGcPoint) != 0;
200 INLINE void dvmInsnSetGcPoint(InsnFlags* insnFlags, int addr,
205 insnFlags[addr] |= kInsnFlagGcPoint;
207 // insnFlags[addr] &= ~kInsnFlagGcPoint;
212 * Table that maps uninitialized instances to classes, based on the
213 * address of the new-instance instruction.
215 typedef struct UninitInstanceMap {
218 int addr; /* code offset, or -1 for method arg ("this") */
219 ClassObject* clazz; /* class created at this address */
222 #define kUninitThisArgAddr (-1)
223 #define kUninitThisArgSlot 0
226 * Create a new UninitInstanceMap.
228 UninitInstanceMap* dvmCreateUninitInstanceMap(const Method* meth,
229 const InsnFlags* insnFlags, int newInstanceCount);
232 * Release the storage associated with an UninitInstanceMap.
234 void dvmFreeUninitInstanceMap(UninitInstanceMap* uninitMap);
237 * Associate a class with an address. Returns the map slot index, or -1
238 * if the address isn't listed in the map (shouldn't happen) or if a
239 * different class is already associated with the address (shouldn't
242 //int dvmSetUninitInstance(UninitInstanceMap* uninitMap, int addr,
243 // ClassObject* clazz);
246 * Return the class associated with an uninitialized reference. Pass in
249 //ClassObject* dvmGetUninitInstance(const UninitInstanceMap* uninitMap, int idx);
252 * Clear the class associated with an uninitialized reference. Pass in
255 //void dvmClearUninitInstance(UninitInstanceMap* uninitMap, int idx);
259 * Verify bytecode in "meth". "insnFlags" should be populated with
260 * instruction widths and "in try" flags.
262 bool dvmVerifyCodeFlow(Method* meth, InsnFlags* insnFlags,
263 UninitInstanceMap* uninitMap);
265 #endif /*_DALVIK_CODEVERIFY*/