com.caucho.bytecode

Class CodeEnhancer

java.lang.Object

com.caucho.bytecode.CodeVisitor

com.caucho.bytecode.CodeEnhancer

public class CodeEnhancer
extends CodeVisitor

Visitor for travelling the code.

Field Summary

Fields inherited from class com.caucho.bytecode.CodeVisitor

_codeAttr, _offset, AALOAD, AASTORE, ACONST_NULL, ALOAD, ALOAD_0, ALOAD_1, ALOAD_2, ALOAD_3, ANEWARRAY, ARETURN, ARRAYLENGTH, ASTORE, ASTORE_0, ASTORE_1, ASTORE_2, ASTORE_3, ATHROW, BALOAD, BASTORE, BIPUSH, CALOAD, CASTORE, CHECKCAST, D2F, D2I, D2L, DADD, DALOAD, DASTORE, DCMPG, DCMPL, DCONST_0, DCONST_1, DDIV, DLOAD, DLOAD_0, DLOAD_1, DLOAD_2, DLOAD_3, DMUL, DNEG, DREM, DRETURN, DSTORE, DSTORE_0, DSTORE_1, DSTORE_2, DSTORE_3, DSUB, DUP, DUP_X1, DUP_X2, DUP2, DUP2_X1, DUP2_X2, F2D, F2I, F2L, FADD, FALOAD, FASTORE, FCMPG, FCMPL, FCONST_0, FCONST_1, FCONST_2, FDIV, FLOAD, FLOAD_0, FLOAD_1, FLOAD_2, FLOAD_3, FMUL, FNEG, FREM, FRETURN, FSTORE, FSTORE_0, FSTORE_1, FSTORE_2, FSTORE_3, FSUB, GETFIELD, GETSTATIC, GOTO, GOTO_W, I2B, I2C, I2D, I2F, I2L, I2S, IADD, IALOAD, IAND, IASTORE, ICONST_0, ICONST_1, ICONST_2, ICONST_3, ICONST_4, ICONST_5, ICONST_M1, IDIV, IF_ACMPEQ, IF_ACMPNE, IF_ICMPEQ, IF_ICMPGE, IF_ICMPGT, IF_ICMPLE, IF_ICMPLT, IF_ICMPNE, IFEQ, IFGE, IFGT, IFLE, IFLT, IFNE, IFNONNULL, IFNULL, IINC, ILOAD, ILOAD_0, ILOAD_1, ILOAD_2, ILOAD_3, IMUL, INEG, INSTANCEOF, INVOKEINTERFACE, INVOKESPECIAL, INVOKESTATIC, INVOKEVIRTUAL, IOR, IREM, IRETURN, ISHL, ISHR, ISTORE, ISTORE_0, ISTORE_1, ISTORE_2, ISTORE_3, ISUB, IUSHR, IXOR, JSR, JSR_W, L2D, L2F, L2I, LADD, LALOAD, LAND, LASTORE, LCMP, LCONST_0, LCONST_1, LDC, LDC_W, LDC2_W, LDIV, LLOAD, LLOAD_0, LLOAD_1, LLOAD_2, LLOAD_3, LMUL, LNEG, LOOKUPSWITCH, LOR, LREM, LRETURN, LSHL, LSHR, LSTORE, LSTORE_0, LSTORE_1, LSTORE_2, LSTORE_3, LSUB, LUSHR, LXOR, MONITORENTER, MONITOREXIT, MULTIANEWARRAY, NEW, NEWARRAY, NOP, POP, POP2, PUTFIELD, PUTSTATIC, RESERVED_0, RET, RETURN, SALOAD, SASTORE, SIPUSH, SWAP, TABLESWITCH, WIDE

Constructor Summary

Constructors

Constructor and Description
CodeEnhancer()
CodeEnhancer(JavaClass javaClass, CodeAttribute code)

Method Summary

Modifier and Type	Method and Description
void	add(int offset, byte[] buffer, int bufOffset, int length) Adds a byte to the code.
void	addByte(int offset, int value) Adds a byte to the code.
void	addNulls(int offset, int count) Adds a byte to the code.
void	addShort(int offset, int value) Adds a short to the code.
void	analyze(Analyzer analyzer, boolean allowFlow) Analyzes the code for a method
protected void	analyzeJumps()
byte[]	getCode() Returns the code buffer.
int	getLength() Returns the length.
void	init(JavaClass javaClass, CodeAttribute codeAttr)
protected void	insertCode(int offset, int count) Updates indices when adding a chunk of code.
void	remove(int offset, int count) Removes a range from the code.
protected void	removeCode(int offset, int count)
void	setByte(int offset, int value) Adds a byte to the code.
void	update() Updates the code.

Methods inherited from class com.caucho.bytecode.CodeVisitor

analyze, analyzeImpl, getBranchTarget, getByte, getByteArg, getByteArg, getCodeAttribute, getConstantArg, getExceptions, getInt, getIntArg, getJavaClass, getOffset, getOpcode, getShort, getShortArg, getShortArg, getSwitchTargets, isBranch, isSwitch, next, nextOffset, setByteArg, setInt, setOffset, setShort, setShortArg

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

CodeEnhancer

public CodeEnhancer()

CodeEnhancer

public CodeEnhancer(JavaClass javaClass,
                    CodeAttribute code)

Method Detail

init

public void init(JavaClass javaClass,
                 CodeAttribute codeAttr)

Overrides:

init in class CodeVisitor

analyze

public void analyze(Analyzer analyzer,
                    boolean allowFlow)
             throws java.lang.Exception

Analyzes the code for a method

Overrides:

analyze in class CodeVisitor

Throws:

java.lang.Exception

getCode

public byte[] getCode()

Returns the code buffer.

Overrides:

getCode in class CodeVisitor

getLength

public int getLength()

Returns the length.

addByte

public void addByte(int offset,
                    int value)

Adds a byte to the code.

setByte

public void setByte(int offset,
                    int value)

Adds a byte to the code.

addShort

public void addShort(int offset,
                     int value)

Adds a short to the code.

add

public void add(int offset,
                byte[] buffer,
                int bufOffset,
                int length)

Adds a byte to the code.

remove

public void remove(int offset,
                   int count)

Removes a range from the code.

addNulls

public void addNulls(int offset,
                     int count)

Adds a byte to the code.

insertCode

protected void insertCode(int offset,
                          int count)

Updates indices when adding a chunk of code. The operation at the given offset moves, e.g. adding 6 bytes to the beginning of the program moves the initial byte down by 6 and therefore needs to update the links as well. Therefore, enhancers which expand an opcode from 2 bytes to 3 bytes must insert the new bytes after the initial opcode.

removeCode

protected void removeCode(int offset,
                          int count)

analyzeJumps

protected void analyzeJumps()

update

public void update()

Updates the code.