/**
* Gets the type of the value at a given index on the operand stack.
*
* @param index the operand stack index
* @return the type of the value at index <code>index</code> on the operand stack
*/
public Klass getStackTypeAt(int index) {
Assert.that(index < sp, "index out of bounds");
if (stack[index] == null) {
return Klass.getSecondWordType(stack[index - 1].getType());
} else {
return stack[index].getType();
}
}
/**
* Emulates the storing of a value to a local variable.
*
* @param index the index of the local variable being stored to
* @param type the type of the value
* @param local the variable to which the value is stored
*/
public void store(int index, Klass type, Local local) {
Klass localType = local.getType();
Assert.that(localType.isAssignableFrom(type) || localType == getLocalTypeFor(type));
verifyLocalVariableIndex(localType, index);
localTypes[index] = type;
if (localType.isDoubleWord()) {
localTypes[index + 1] = Klass.getSecondWordType(localType);
} else {
verifyUseOfSquawkPrimitive(localType, type);
}
}
/**
* Emulates loading a value of a given type from a local variable.
*
* @param index the index of the local variable being loaded from
* @param localType the expected type of the variable from which the value is loaded
* @return the variable from which the value is loaded
*/
public Local load(int index, Klass localType) {
verifyLocalVariableIndex(localType, index);
Klass derivedType = localTypes[index];
if (!localType.isAssignableFrom(derivedType)) {
throw codeParser.verifyError("incompatible type in local variable");
}
if (localType.isDoubleWord()) {
Klass secondWordType = Klass.getSecondWordType(localType);
if (!secondWordType.isAssignableFrom(localTypes[index + 1])) {
throw codeParser.verifyError("incompatible type in local variable");
}
}
if (derivedType.isSquawkPrimitive()) {
localType = derivedType;
}
return allocateLocal(localType, index);
}