at.dms.classfile
Class JumpInstruction

java.lang.Object
  extended by at.dms.classfile.AbstractInstructionAccessor
      extended by at.dms.classfile.Instruction
          extended by at.dms.classfile.JumpInstruction
All Implemented Interfaces:
AccessorContainer, Constants, InstructionAccessor

public class JumpInstruction
extends Instruction
implements AccessorContainer

This class represents instructions that take a label as argument. Only goto and jsr instructions have wide variants for targets that are too far away to have their relative address stored in a short. For jump instructions except goto and jsr with a target that is too far away, an additional goto_w has to be generated. For example : ifne A B: ... will be transformed into : ifeq B goto_w A B: ... Note that the condition has been inverted in the transformed code.


Field Summary
 
Fields inherited from interface at.dms.classfile.Constants
ACC_ABSTRACT, ACC_FINAL, ACC_INLINE, ACC_INTERFACE, ACC_NATIVE, ACC_PRIVATE, ACC_PROTECTED, ACC_PUBLIC, ACC_STATIC, ACC_STRICT, ACC_SUPER, ACC_SYNCHRONIZED, ACC_TRANSIENT, ACC_VOLATILE, ATT_CODE, ATT_CONSTANTVALUE, ATT_DEPRECATED, ATT_EXCEPTIONS, ATT_GENERIC, ATT_INNERCLASSES, ATT_LINENUMBERTABLE, ATT_LOCALVARIABLETABLE, ATT_SOURCEFILE, ATT_SYNTHETIC, CST_CLASS, CST_DOUBLE, CST_FIELD, CST_FLOAT, CST_INTEGER, CST_INTERFACEMETHOD, CST_LONG, CST_METHOD, CST_NAMEANDTYPE, CST_STRING, CST_UTF8, ENV_DEBUG_MODE, ENV_USE_CACHE, JAVA_MAGIC, JAVA_MAJOR, JAVA_MINOR, MAX_CODE_PER_METHOD, opc_aaload, opc_aastore, opc_aconst_null, opc_aload, opc_aload_0, opc_aload_1, opc_aload_2, opc_aload_3, opc_anewarray, opc_areturn, opc_arraylength, opc_astore, opc_astore_0, opc_astore_1, opc_astore_2, opc_astore_3, opc_athrow, opc_baload, opc_bastore, opc_bipush, opc_caload, opc_castore, opc_checkcast, opc_d2f, opc_d2i, opc_d2l, opc_dadd, opc_daload, opc_dastore, opc_dcmpg, opc_dcmpl, opc_dconst_0, opc_dconst_1, opc_ddiv, opc_dload, opc_dload_0, opc_dload_1, opc_dload_2, opc_dload_3, opc_dmul, opc_dneg, opc_drem, opc_dreturn, opc_dstore, opc_dstore_0, opc_dstore_1, opc_dstore_2, opc_dstore_3, opc_dsub, opc_dup, opc_dup_x1, opc_dup_x2, opc_dup2, opc_dup2_x1, opc_dup2_x2, opc_f2d, opc_f2i, opc_f2l, opc_fadd, opc_faload, opc_fastore, opc_fcmpg, opc_fcmpl, opc_fconst_0, opc_fconst_1, opc_fconst_2, opc_fdiv, opc_fload, opc_fload_0, opc_fload_1, opc_fload_2, opc_fload_3, opc_fmul, opc_fneg, opc_frem, opc_freturn, opc_fstore, opc_fstore_0, opc_fstore_1, opc_fstore_2, opc_fstore_3, opc_fsub, opc_getfield, opc_getstatic, opc_goto, opc_goto_w, opc_i2b, opc_i2c, opc_i2d, opc_i2f, opc_i2l, opc_i2s, opc_iadd, opc_iaload, opc_iand, opc_iastore, opc_iconst_0, opc_iconst_1, opc_iconst_2, opc_iconst_3, opc_iconst_4, opc_iconst_5, opc_iconst_m1, opc_idiv, opc_if_acmpeq, opc_if_acmpne, opc_if_icmpeq, opc_if_icmpge, opc_if_icmpgt, opc_if_icmple, opc_if_icmplt, opc_if_icmpne, opc_ifeq, opc_ifge, opc_ifgt, opc_ifle, opc_iflt, opc_ifne, opc_ifnonnull, opc_ifnull, opc_iinc, opc_iload, opc_iload_0, opc_iload_1, opc_iload_2, opc_iload_3, opc_imul, opc_ineg, opc_instanceof, opc_invokeinterface, opc_invokespecial, opc_invokestatic, opc_invokevirtual, opc_ior, opc_irem, opc_ireturn, opc_ishl, opc_ishr, opc_istore, opc_istore_0, opc_istore_1, opc_istore_2, opc_istore_3, opc_isub, opc_iushr, opc_ixor, opc_jsr, opc_jsr_w, opc_l2d, opc_l2f, opc_l2i, opc_ladd, opc_laload, opc_land, opc_lastore, opc_lcmp, opc_lconst_0, opc_lconst_1, opc_ldc, opc_ldc_w, opc_ldc2_w, opc_ldiv, opc_lload, opc_lload_0, opc_lload_1, opc_lload_2, opc_lload_3, opc_lmul, opc_lneg, opc_lookupswitch, opc_lor, opc_lrem, opc_lreturn, opc_lshl, opc_lshr, opc_lstore, opc_lstore_0, opc_lstore_1, opc_lstore_2, opc_lstore_3, opc_lsub, opc_lushr, opc_lxor, opc_monitorenter, opc_monitorexit, opc_multianewarray, opc_new, opc_newarray, opc_nop, opc_pop, opc_pop2, opc_putfield, opc_putstatic, opc_ret, opc_return, opc_saload, opc_sastore, opc_sipush, opc_swap, opc_tableswitch, opc_wide, opc_xxxunusedxxx, POO_ASCII_CONSTANT, POO_CLASS_CONSTANT, POO_DOUBLE_CONSTANT, POO_FLOAT_CONSTANT, POO_INTEGER_CONSTANT, POO_LONG_CONSTANT, POO_NAT_CONSTANT, POO_REF_CONSTANT, POO_STRING_CONSTANT, TYP_ADDRESS, TYP_DOUBLE, TYP_FLOAT, TYP_INT, TYP_LONG, TYP_REFERENCE, TYP_VOID
 
Constructor Summary
JumpInstruction(int opcode, InstructionAccessor target)
          Constructs a new instruction that takes a label as argument.
 
Method Summary
 boolean canComplete()
          Returns true iff control flow can reach the next instruction in textual order.
 void dump()
           
 int getPushedOnStack()
          Returns the size of data pushed on the stack by this instruction
 byte getReturnType()
          Returns the type pushed on the stack
 int getStack()
          Return the amount of stack (positive or negative) used by this instruction
 InstructionAccessor getTarget()
          Return the target of this instruction
 void setTarget(InstructionAccessor target)
          Sets the target for this instruction
 void transformAccessors(AccessorTransformer transformer)
          Transforms targets (deferences to actual instructions).
 
Methods inherited from class at.dms.classfile.Instruction
getOpcode, getPoppedFromStack, isLiteral
 
Methods inherited from class at.dms.classfile.AbstractInstructionAccessor
deepClone, deepCloneInto, transform
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

JumpInstruction

public JumpInstruction(int opcode,
                       InstructionAccessor target)
Constructs a new instruction that takes a label as argument.

Parameters:
opcode - the opcode of the instruction
target - the referenced instruction
Method Detail

canComplete

public boolean canComplete()
Returns true iff control flow can reach the next instruction in textual order.

Specified by:
canComplete in class Instruction

transformAccessors

public void transformAccessors(AccessorTransformer transformer)
                        throws BadAccessorException
Transforms targets (deferences to actual instructions).

Specified by:
transformAccessors in interface AccessorContainer
Parameters:
transformer - the transformer used to transform accessors
Throws:
BadAccessorException

setTarget

public void setTarget(InstructionAccessor target)
Sets the target for this instruction


getTarget

public InstructionAccessor getTarget()
Return the target of this instruction


getPushedOnStack

public int getPushedOnStack()
Returns the size of data pushed on the stack by this instruction

Specified by:
getPushedOnStack in class Instruction

getReturnType

public byte getReturnType()
Returns the type pushed on the stack

Specified by:
getReturnType in class Instruction

getStack

public int getStack()
Return the amount of stack (positive or negative) used by this instruction

Specified by:
getStack in class Instruction

dump

public void dump()
Overrides:
dump in class Instruction