opcodestack.java

一个查找java程序里bug的程序的源代码,该程序本身也是java写的,对提高java编程水平很有用

	 				}
	 			break;

	 			case DNEG:
	 				it = pop();
	 				if (it.getConstant() != null) {
	 					push(new Item("D", new Double(-((Double)it.getConstant()).doubleValue())));
	 				} else {
	 					push(new Item("D"));
	 				}
	 			break;

	 			case LADD:
	 			case LSUB:
	 			case LMUL:
	 			case LDIV:
	 			case LAND:
	 			case LOR:
	 			case LXOR:
	 			case LSHL:
	 			case LSHR:
	 			case LREM:
	 			case LUSHR:
	 				it = pop();
	 				it2 = pop();
	 				pushByLongMath(seen, it, it2);
	 			break;
 			
	 			case LCMP:
	 				it = pop();
	 				it2 = pop();
	 				if ((it.getConstant() != null) && it2.getConstant() != null) {
	 					long l = ((Long)it.getConstant()).longValue();
	 					long l2 = ((Long)it.getConstant()).longValue();
	 					if (l2 < l)
	 						push(new Item("I", new Integer(-1)));
	 					else if (l2 > l)
	 						push(new Item("I", new Integer(1)));
	 					else
	 						push(new Item("I", new Integer(0)));
	 				} else {
	 					push(new Item("I"));
	 				}
	 			break;
	 				
	 			case FCMPG:
	 			case FCMPL:
	 				it = pop();
	 				it2 = pop();
	 				if ((it.getConstant() != null) && it2.getConstant() != null) {
	 					float f = ((Float)it.getConstant()).floatValue();
	 					float f2 = ((Float)it.getConstant()).floatValue();
	 					if (f2 < f)
	 						push(new Item("I", new Integer(-1)));
	 					else if (f2 > f)
	 						push(new Item("I", new Integer(1)));
	 					else
	 						push(new Item("I", new Integer(0)));
	 				} else {
	 					push(new Item("I"));
	 				}
	 			break;

	 			case DCMPG:
	 			case DCMPL:
	 				it = pop();
	 				it2 = pop();
	 				if ((it.getConstant() != null) && it2.getConstant() != null) {
	 					double d = ((Double)it.getConstant()).doubleValue();
	 					double d2 = ((Double)it.getConstant()).doubleValue();
	 					if (d2 < d)
	 						push(new Item("I", new Integer(-1)));
	 					else if (d2 > d)
	 						push(new Item("I", new Integer(1)));
	 					else
	 						push(new Item("I", new Integer(0)));
	 				} else {
	 					push(new Item("I"));
	 				}
	 			break;
	 			
	 			case FADD:
	 			case FSUB:
	 			case FMUL:
	 			case FDIV:
	 				it = pop();
	 				it2 = pop();
	 				pushByFloatMath(seen, it, it2);
	 			break;

	 			case DADD:
	 			case DSUB:
	 			case DMUL:
	 			case DDIV:
	 			case DREM:
	 				it = pop();
	 				it2 = pop();
	 				pushByDoubleMath(seen, it, it2);
	 			break;
	 			
	 			case I2B:
	 				it = pop();
	 				if (it.getConstant() != null) {
	 					push(new Item("I", new Integer((int)((byte)((Integer)it.getConstant()).intValue()))));
	 				} else {
	 					push(new Item("I"));
	 				}
	 			break;

	 			case I2C:
	 				it = pop();
	 				if (it.getConstant() != null) {
	 					push(new Item("I", new Integer((int)((char)((Integer)it.getConstant()).intValue()))));
	 				} else {
	 					push(new Item("I"));
	 				}
	 			break;

	 			case I2D:
	 				it = pop();
	 				if (it.getConstant() != null) {
	 					push(new Item("D", new Double((double)((Integer)it.getConstant()).intValue())));
	 				} else {
	 					push(new Item("D"));
	 				}
	 			break;
	 			
	 			case I2F:
	 				it = pop();
	 				if (it.getConstant() != null) {
	 					push(new Item("F", new Float((float)((Integer)it.getConstant()).intValue())));
	 				} else {
	 					push(new Item("F"));
	 				}
	 			break;
	 			
	 			case I2L:
	 				it = pop();
	 				if (it.getConstant() != null) {
	 					push(new Item("J", new Long((long)((Integer)it.getConstant()).intValue())));
	 				} else {
	 					push(new Item("J"));
	 				}
	 			break;

	 			case I2S:
	 				it = pop();
	 				if (it.getConstant() != null) {
	 					push(new Item("I", new Integer((int)((short)((Integer)it.getConstant()).intValue()))));
	 				} else {
	 					push(new Item("I"));
	 				}
	 			break;
	 			
	 			case D2I:
	 				it = pop();
	 				if (it.getConstant() != null) {
	 					push(new Item("I", new Integer((int)((Integer)it.getConstant()).intValue())));
	 				} else {
	 					push(new Item("I"));
	 				}
	 			break;
	 			
	 			case D2F:
	 				it = pop();
	 				if (it.getConstant() != null) {
	 					push(new Item("F", new Float((float)((Double)it.getConstant()).doubleValue())));
	 				} else {
	 					push(new Item("F"));
	 				}
	 			break;

	 			case D2L:
	 				it = pop();
	 				if (it.getConstant() != null) {
	 					push(new Item("J", new Long((long)((Double)it.getConstant()).doubleValue())));
	 				} else {
	 					push(new Item("J"));
	 				}
	 			break;

	 			case L2I:
	 				it = pop();
	 				if (it.getConstant() != null) {
	 					push(new Item("I", new Integer((int)((Long)it.getConstant()).longValue())));
	 				} else {
	 					push(new Item("I"));
	 				}
	 			break;
	 			
	 			case L2D:
	 				it = pop();
	 				if (it.getConstant() != null) {
	 					push(new Item("D", new Double((double)((Long)it.getConstant()).longValue())));
	 				} else {
	 					push(new Item("D"));
	 				}
	 			break;
	 			
	 			case L2F:
	 				it = pop();
	 				if (it.getConstant() != null) {
	 					push(new Item("F", new Float((float)((Long)it.getConstant()).longValue())));
	 				} else {
	 					push(new Item("F"));
	 				}
	 			break;

	 			case F2I:
	 				it = pop();
	 				if (it.getConstant() != null) {
	 					push(new Item("I", new Integer((int)((Float)it.getConstant()).floatValue())));
	 				} else {
	 					push(new Item("I"));
	 				}
	 			break;

	 			case F2D:
	 				it = pop();
	 				if (it.getConstant() != null) {
	 					push(new Item("D", new Double((double)((Float)it.getConstant()).floatValue())));
	 				} else {
	 					push(new Item("D"));
	 				}
	 			break;
	 			
	 			case NEW:
	 				pushBySignature(dbc.getClassConstantOperand());
	 			break;
	 			
	 			case NEWARRAY:
	 				pop();
	 				signature = BasicType.getType((byte)dbc.getIntConstant()).getSignature();
	 				pushBySignature(signature);
	 			break;

				// According to the VM Spec 4.4.1, anewarray and multianewarray
				// can refer to normal class/interface types (encoded in
				// "internal form"), or array classes (encoded as signatures
				// beginning with "[").
	 			
	 			case ANEWARRAY:
	 				pop();
					signature = dbc.getClassConstantOperand();
					if (!signature.startsWith("[")) {
						signature = "L" + signature + ";";
					}
	 				pushBySignature(signature);
	 			break;
	 			
	 			case MULTIANEWARRAY:
	 				int dims = dbc.getIntConstant();
	 				while ((dims--) > 0) {
	 					pop();
	 				}
					signature = dbc.getClassConstantOperand();
					if (!signature.startsWith("[")) {
						signature = "L" + signature + ";";
					}
					pushBySignature(signature);
	 			break;
	 				
	 			case AALOAD:
	 				pop();
	 				it = pop();
	 				pushBySignature(it.getElementSignature());
	 			break;
	 				 			
	 			case JSR:
	 				push(new Item("")); //?
	 			break;
	 			
				case INVOKEINTERFACE:
	 			case INVOKESPECIAL:
	 			case INVOKESTATIC:
	 			case INVOKEVIRTUAL:
	 				pushByInvoke(dbc, seen != INVOKESTATIC);
	 			break;
	 				
	 			default:
	 				throw new UnsupportedOperationException("OpCode not supported yet" );
	 		}
	 	}
/*
		// FIXME: This class currently relies on catching runtime exceptions.
		// This should be fixed so they don't occur.
		catch (RuntimeException e) {
			throw e;
		}
*/
	 	catch (Exception e) {
	 		//If an error occurs, we clear the stack and locals. one of two things will occur. 
	 		//Either the client will expect more stack items than really exist, and so they're condition check will fail, 
	 		//or the stack will resync with the code. But hopefully not false positives
	 		stack.clear();
	 		lvValues.clear();
	 	}
	 	finally {
	 		if (DEBUG)
	 			System.out.println(OPCODE_NAMES[seen] + "  stack depth: " + getStackDepth());
	 	}
 	}
 	
 	public int getStackDepth() {
 		return stack.size();
 	}
 	
 	public Item getStackItem(int stackOffset) {
 		int tos = stack.size() - 1;
 		int pos = tos - stackOffset;
 		return stack.get(pos);
 	} 
 	
 	 private Item pop() {
 		return stack.remove(stack.size()-1);
 	}
 	
 	private void pop(int count)
 	{
 		while ((count--) > 0)
 			pop();
 	}
 	
 	private void push(Item i) {
 		stack.add(i);
 	}
 	
 	private void pushByConstant(DismantleBytecode dbc, Constant c) {
 		
		if (c instanceof ConstantInteger)
			push(new Item("I", new Integer(((ConstantInteger) c).getBytes())));
		else if (c instanceof ConstantString) {
			int s = ((ConstantString) c).getStringIndex();
			push(new Item("Ljava/lang/String;", getStringFromIndex(dbc, s)));
		}
		else if (c instanceof ConstantFloat)
			push(new Item("F", new Float(((ConstantInteger) c).getBytes())));
		else if (c instanceof ConstantDouble)
			push(new Item("D", new Double(((ConstantDouble) c).getBytes())));
		else if (c instanceof ConstantLong)
			push(new Item("J", new Long(((ConstantLong) c).getBytes())));
		else
			throw new UnsupportedOperationException("Constant type not expected" );
 	}
 	
 	private void pushByLocalObjectLoad(DismantleBytecode dbc, int register) {
		Method m = dbc.getMethod();
		LocalVariableTable lvt = m.getLocalVariableTable();
		if (lvt != null) {
			LocalVariable lv = LVTHelper.getLocalVariableAtPC(lvt, register, dbc.getPC());
			if (lv != null) {
				String signature = lv.getSignature();
				pushByLocalLoad(signature, register);
				return;
			}
		}
		pushBySignature("");
 	}
 	
 	private void pushByIntMath(int seen, Item it, Item it2) {
 		if ((it.getConstant() != null) && it2.getConstant() != null) {
			if (seen == IADD)
				push(new Item("I", new Integer(((Integer)it2.getConstant()).intValue() + ((Integer)it.getConstant()).intValue())));
			else if (seen == ISUB)
				push(new Item("I", new Integer(((Integer)it2.getConstant()).intValue() - ((Integer)it.getConstant()).intValue())));
			else if (seen == IMUL)
				push(new Item("I", new Integer(((Integer)it2.getConstant()).intValue() * ((Integer)it.getConstant()).intValue())));
			else if (seen == IDIV)
				push(new Item("I", new Integer(((Integer)it2.getConstant()).intValue() / ((Integer)it.getConstant()).intValue())));
			else if (seen == IAND)
				push(new Item("I", new Integer(((Integer)it2.getConstant()).intValue() & ((Integer)it.getConstant()).intValue())));
			else if (seen == IOR)
				push(new Item("I", new Integer(((Integer)it2.getConstant()).intValue() | ((Integer)it.getConstant()).intValue())));
			else if (seen == IXOR)
				push(new Item("I", new Integer(((Integer)it2.getConstant()).intValue() ^ ((Integer)it.getConstant()).intValue())));
			else if (seen == ISHL)
				push(new Item("I", new Integer(((Integer)it2.getConstant()).intValue() << ((Integer)it.getConstant()).intValue())));
			else if (seen == ISHR)
				push(new Item("I", new Integer(((Integer)it2.getConstant()).intValue() >> ((Integer)it.getConstant()).intValue())));
			else if (seen == IREM)
				push(new Item("I", new Integer(((Integer)it2.getConstant()).intValue() % ((Integer)it.getConstant()).intValue())));
			else if (seen == IUSHR)
				push(new Item("I", new Integer(((Integer)it2.getConstant()).intValue() >>> ((Integer)it.getConstant()).intValue())));
		} else {
			push(new Item("I"));
		}
	}
	
	private void pushByLongMath(int seen, Item it, Item it2) {
		if ((it.getConstant() != null) && it2.getConstant() != null) {
			if (seen == LADD)
				push(new Item("J", new Long(((Long)it2.getConstant()).longValue() + ((Long)it.getConstant()).longValue())));
			else if (seen == LSUB)
				push(new Item("J", new Long(((Long)it2.getConstant()).longValue() - ((Long)it.getConstant()).longValue())));
			else if (seen == LMUL)
				push(new Item("J", new Long(((Long)it2.getConstant()).longValue() * ((Long)it.getConstant()).longValue())));
			else if (seen == LDIV)
				push(new Item("J", new Long(((Long)it2.getConstant()).longValue() / ((Long)it.getConstant()).longValue())));
			else if (seen == LAND)
				push(new Item("J", new Long(((Long)it2.getConstant()).longValue() & ((Long)it.getConstant()).longValue())));
			else if (seen == LOR)
				push(new Item("J", new Long(((Long)it2.getConstant()).longValue() | ((Long)it.getConstant()).longValue())));
			else if (seen == LXOR)
				push(new Item("J", new Long(((Long)it2.getConstant()).longValue() ^ ((Long)it.getConstant()).longValue())));
			else if (seen == LSHL)
				push(new Item("J", new Long(((Long)it2.getConstant()).longValue() << ((Long)it.getConstant()).longValue())));
			else if (seen == LSHR)
				push(new Item("J", new Long(((Long)it2.getConstant()).longValue() >> ((Long)it.getConstant()).longValue())));
			else if (seen == LREM)
				push(new Item("J", new Long(((Long)it2.getConstant()).longValue() % ((Long)it.getConstant()).longValue())));
			else if (seen == LUSHR)
				push(new Item("J", new Long(((Long)it2.getConstant()).longValue() >>> ((Long)it.getConstant()).longValue())));
		} else {
			push(new Item("J"));
		}
	}
	
	private void pushByFloatMath(int seen, Item it, Item it2) {
		if ((it.getConstant() != null) && it2.getConstant() != null) {
			if (seen == FADD)
				push(new Item("F", new Float(((Float)it2.getConstant()).floatValue() + ((Float)it.getConstant()).floatValue())));
			else if (seen == FSUB)
				push(new Item("F", new Float(((Float)it2.getConstant()).floatValue() - ((Float)it.getConstant()).floatValue())));
			else if (seen == FMUL)
				push(new Item("F", new Float(((Float)it2.getConstant()).floatValue() * ((Float)it.getConstant()).floatValue())));
			else if (seen == FDIV)
				push(new Item("F", new Float(((Float)it2.getConstant()).floatValue() / ((Float)it.getConstant()).floatValue())));
		} else {
			push(new Item("F"));
		}
	}
	
	private void pushByDoubleMath(int seen, Item it, Item it2) {
		if ((it.getConstant() != null) && it2.getConstant() != null) {
			if (seen == DADD)
				push(new Item("D", new Double(((Double)it2.getConstant()).doubleValue() + ((Double)it.getConstant()).doubleValue())));
			else if (seen == DSUB)
				push(new Item("D", new Double(((Double)it2.getConstant()).doubleValue() - ((Double)it.getConstant()).doubleValue())));
			else if (seen == DMUL)
				push(new Item("D", new Double(((Double)it2.getConstant()).doubleValue() * ((Double)it.getConstant()).doubleValue())));
			else if (seen == DDIV)
				push(new Item("D", new Double(((Double)it2.getConstant()).doubleValue() / ((Double)it.getConstant()).doubleValue())));
			else if (seen == DREM)
				push(new Item("D"));	//?	
			} else {
			push(new Item("D"));
		}
	}
	
	private void pushByInvoke(DismantleBytecode dbc, boolean popThis) {
		String signature = dbc.getSigConstantOperand();
		Type[] argTypes = Type.getArgumentTypes(signature);
		pop(argTypes.length+(popThis ? 1 : 0));
		pushBySignature(Type.getReturnType(signature).getSignature());
	}
 	
	private String getStringFromIndex(DismantleBytecode dbc, int i) {
		ConstantUtf8 name = (ConstantUtf8) dbc.getConstantPool().getConstant(i);
		return name.getBytes();
	}
	
	private void pushBySignature(String s) {
 		if ("V".equals(s))
 			return;
 	 	push(new Item(s, null));
 	}
 	
 	private void pushByLocalStore(int register) {
		Item it = pop();
		setLVValue( register, it );
 	}
 	
 	private void pushByLocalLoad(String signature, int register) {
		Item it = getLVValue(register);
		if (it == null)
			push(new Item(signature));
		else
			push(it);
 	}
 	
 	private void setLVValue(int index, Item value ) {
 		int addCount = index - lvValues.size() + 1;
 		while ((addCount--) > 0)
 			lvValues.add(null);
 		lvValues.set(index, value );
 	}
 	
 	private Item getLVValue(int index) {
 		if (index >= lvValues.size())
 			return null;
 			
 		return lvValues.get(index);
 	}
}

// vim:ts=4