/*
* Copyright (C) 2008 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/*
* Dalvik bytecode verifier.
*/
#ifndef _DALVIK_CODEVERIFY
#define _DALVIK_CODEVERIFY
#include "analysis/VerifySubs.h"
/*
* Enumeration for register type values. The "hi" piece of a 64-bit value
* MUST immediately follow the "lo" piece in the enumeration, so we can check
* that hi==lo+1.
*
* Assignment of constants:
* [-MAXINT,-32768) : integer
* [-32768,-128) : short
* [-128,0) : byte
* 0 : zero
* 1 : one
* [2,128) : posbyte
* [128,32768) : posshort
* [32768,65536) : char
* [65536,MAXINT] : integer
*
* Allowed "implicit" widening conversions:
* zero -> boolean, posbyte, byte, posshort, short, char, integer, ref (null)
* one -> boolean, posbyte, byte, posshort, short, char, integer
* boolean -> posbyte, byte, posshort, short, char, integer
* posbyte -> posshort, short, integer, char
* byte -> short, integer
* posshort -> integer, char
* short -> integer
* char -> integer
*
* In addition, all of the above can convert to "float".
*
* We're more careful with integer values than the spec requires. The
* motivation is to restrict byte/char/short to the correct range of values.
* For example, if a method takes a byte argument, we don't want to allow
* the code to load the constant "1024" and pass it in.
*/
enum {
kRegTypeUnknown = 0, /* initial state; use value=0 so calloc works */
kRegTypeUninit = 1, /* MUST be odd to distinguish from pointer */
kRegTypeConflict, /* merge clash makes this reg's type unknowable */
/*
* Category-1nr types. The order of these is chiseled into a couple
* of tables, so don't add, remove, or reorder if you can avoid it.
*/
#define kRegType1nrSTART kRegTypeFloat
kRegTypeFloat,
kRegTypeZero, /* 32-bit 0, could be Boolean, Int, Float, or Ref */
kRegTypeOne, /* 32-bit 1, could be Boolean, Int, Float */
kRegTypeBoolean, /* must be 0 or 1 */
kRegTypePosByte, /* byte, known positive (can become char) */
kRegTypeByte,
kRegTypePosShort, /* short, known positive (can become char) */
kRegTypeShort,
kRegTypeChar,
kRegTypeInteger,
#define kRegType1nrEND kRegTypeInteger
kRegTypeLongLo, /* lower-numbered register; endian-independent */
kRegTypeLongHi,
kRegTypeDoubleLo,
kRegTypeDoubleHi,
/*
* Enumeration max; this is used with "full" (32-bit) RegType values.
*
* Anything larger than this is a ClassObject or uninit ref. Mask off
* all but the low 8 bits; if you're left with kRegTypeUninit, pull
* the uninit index out of the high 24. Because kRegTypeUninit has an
* odd value, there is no risk of a particular ClassObject pointer bit
* pattern being confused for it (assuming our class object allocator
* uses word alignment).
*/
kRegTypeMAX
};
#define kRegTypeUninitMask 0xff
#define kRegTypeUninitShift 8
/*
* RegType holds information about the type of data held in a register.
* For most types it's a simple enum. For reference types it holds a
* pointer to the ClassObject, and for uninitialized references it holds
* an index into the UninitInstanceMap.
*/
typedef u4 RegType;
/* table with merge logic for primitive types */
extern const char gDvmMergeTab[kRegTypeMAX][kRegTypeMAX];
/*
* Returns "true" if the flags indicate that this address holds the start
* of an instruction.
*/
INLINE bool dvmInsnIsOpcode(const InsnFlags* insnFlags, int addr) {
return (insnFlags[addr] & kInsnFlagWidthMask) != 0;
}
/*
* Extract the unsigned 16-bit instruction width from "flags".
*/
INLINE int dvmInsnGetWidth(const InsnFlags* insnFlags, int addr) {
return insnFlags[addr] & kInsnFlagWidthMask;
}
/*
* Changed?
*/
INLINE bool dvmInsnIsChanged(const InsnFlags* insnFlags, int addr) {
return (insnFlags[addr] & kInsnFlagChanged) != 0;
}
INLINE void dvmInsnSetChanged(InsnFlags* insnFlags, int addr, bool changed)
{
if (changed)
insnFlags[addr] |= kInsnFlagChanged;
else
insnFlags[addr] &= ~kInsnFlagChanged;
}
/*
* Visited?
*/
INLINE bool dvmInsnIsVisited(const InsnFlags* insnFlags, int addr) {
return (insnFlags[addr] & kInsnFlagVisited) != 0;
}
INLINE void dvmInsnSetVisited(InsnFlags* insnFlags, int addr, bool changed)
{
if (changed)
insnFlags[addr] |= kInsnFlagVisited;
else
insnFlags[addr] &= ~kInsnFlagVisited;
}
/*
* Visited or changed?
*/
INLINE bool dvmInsnIsVisitedOrChanged(const InsnFlags* insnFlags, int addr) {
return (insnFlags[addr] & (kInsnFlagVisited|kInsnFlagChanged)) != 0;
}
/*
* In a "try" block?
*/
INLINE bool dvmInsnIsInTry(const InsnFlags* insnFlags, int addr) {
return (insnFlags[addr] & kInsnFlagInTry) != 0;
}
INLINE void dvmInsnSetInTry(InsnFlags* insnFlags, int addr, bool inTry)
{
assert(inTry);
//if (inTry)
insnFlags[addr] |= kInsnFlagInTry;
//else
// insnFlags[addr] &= ~kInsnFlagInTry;
}
/*
* Instruction is a branch target or exception handler?
*/
INLINE bool dvmInsnIsBranchTarget(const InsnFlags* insnFlags, int addr) {
return (insnFlags[addr] & kInsnFlagBranchTarget) != 0;
}
INLINE void dvmInsnSetBranchTarget(InsnFlags* insnFlags, int addr,
bool isBranch)
{
assert(isBranch);
//if (isBranch)
insnFlags[addr] |= kInsnFlagBranchTarget;
//else
// insnFlags[addr] &= ~kInsnFlagBranchTarget;
}
/*
* Instruction is a GC point?
*/
INLINE bool dvmInsnIsGcPoint(const InsnFlags* insnFlags, int addr) {
return (insnFlags[addr] & kInsnFlagGcPoint) != 0;
}
INLINE void dvmInsnSetGcPoint(InsnFlags* insnFlags, int addr,
bool isGcPoint)
{
assert(isGcPoint);
//if (isGcPoint)
insnFlags[addr] |= kInsnFlagGcPoint;
//else
// insnFlags[addr] &= ~kInsnFlagGcPoint;
}
/*
* Table that maps uninitialized instances to classes, based on the
* address of the new-instance instruction.
*/
typedef struct UninitInstanceMap {
int numEntries;
struct {
int addr; /* code offset, or -1 for method arg ("this") */
ClassObject* clazz; /* class created at this address */
} map[1];
} UninitInstanceMap;
#define kUninitThisArgAddr (-1)
#define kUninitThisArgSlot 0
/*
* Create a new UninitInstanceMap.
*/
UninitInstanceMap* dvmCreateUninitInstanceMap(const Method* meth,
const InsnFlags* insnFlags, int newInstanceCount);
/*
* Release the storage associated with an UninitInstanceMap.
*/
void dvmFreeUninitInstanceMap(UninitInstanceMap* uninitMap);
/*
* Associate a class with an address. Returns the map slot index, or -1
* if the address isn't listed in the map (shouldn't happen) or if a
* different class is already associated with the address (shouldn't
* happen either).
*/
//int dvmSetUninitInstance(UninitInstanceMap* uninitMap, int addr,
// ClassObject* clazz);
/*
* Return the class associated with an uninitialized reference. Pass in
* the map index.
*/
//ClassObject* dvmGetUninitInstance(const UninitInstanceMap* uninitMap, int idx);
/*
* Clear the class associated with an uninitialized reference. Pass in
* the map index.
*/
//void dvmClearUninitInstance(UninitInstanceMap* uninitMap, int idx);
/*
* Verify bytecode in "meth". "insnFlags" should be populated with
* instruction widths and "in try" flags.
*/
bool dvmVerifyCodeFlow(Method* meth, InsnFlags* insnFlags,
UninitInstanceMap* uninitMap);
#endif /*_DALVIK_CODEVERIFY*/