@Override
public AddressValue addressValue(ExpressionNode lhs) throws SyntaxException {
if (lhs instanceof IdentifierExpressionNode) {
Entity entity = ((IdentifierExpressionNode) lhs).getIdentifier().getEntity();
EntityKind kind = entity.getEntityKind();
if (kind == EntityKind.VARIABLE) {
return variableReference((Variable) entity);
} else if (kind == EntityKind.FUNCTION) {
return functionReference((Function) entity);
} else {
throw error("Operand of & not variable or function identifier", lhs);
}
} else if (lhs instanceof DotNode) {
AddressValue structureOrUnionReference = addressValue(((DotNode) lhs).getStructure());
Field field = (Field) ((DotNode) lhs).getFieldName().getEntity();
return memberReference(structureOrUnionReference, field);
} else if (lhs instanceof OperatorNode) {
OperatorNode opNode = (OperatorNode) lhs;
Operator operator = ((OperatorNode) lhs).getOperator();
if (operator == Operator.SUBSCRIPT) {
AddressValue arrayReference = addressValue(opNode.getArgument(0));
Value index = evaluate(opNode.getArgument(1));
return arrayElementReference(arrayReference, index);
} else if (operator == Operator.DEREFERENCE) {
return (AddressValue) evaluate(opNode.getArgument(0));
}
}
throw error("Cannot take address of expression", lhs);
}
/**
* Evaluates a constant expression.
*
* <p>Should apply conversions to result.
*
* @param expr
* @return
* @throws SyntaxException
* @throws UnsourcedException if expr is not a constant expression
*/
private Value evaluateHelper(ExpressionNode expr) throws SyntaxException, UnsourcedException {
if (expr instanceof AlignOfNode) {
return alignofValue(((AlignOfNode) expr).getArgument().getType());
} else if (expr instanceof ArrowNode) {
ArrowNode arrowNode = (ArrowNode) expr;
ExpressionNode structOrUnionPointer = arrowNode.getStructurePointer();
IdentifierNode fieldIdentifier = arrowNode.getFieldName();
Field field = (Field) fieldIdentifier.getEntity();
Value structOrUnionValue = evaluateDereference(structOrUnionPointer);
return evaluateMemberAccess(structOrUnionValue, field);
} else if (expr instanceof CastNode) {
CastNode castNode = (CastNode) expr;
return evaluateCast(castNode.getCastType().getType(), evaluate(castNode.getArgument()));
} else if (expr instanceof CharacterConstantNode) {
return ((CharacterConstantNode) expr).getConstantValue();
} else if (expr instanceof CompoundLiteralNode) {
return evaluateCompoundLiteral((CompoundLiteralNode) expr);
} else if (expr instanceof ConstantNode) {
return ((ConstantNode) expr).getConstantValue();
} else if (expr instanceof DotNode) {
DotNode dotNode = (DotNode) expr;
ExpressionNode structOrUnion = dotNode.getStructure();
IdentifierNode fieldIdentifier = dotNode.getFieldName();
Field field = (Field) fieldIdentifier.getEntity();
Value structOrUnionValue = evaluate(structOrUnion);
return evaluateMemberAccess(structOrUnionValue, field);
} else if (expr instanceof OperatorNode) {
OperatorNode opNode = (OperatorNode) expr;
Operator operator = opNode.getOperator();
if (operator == Operator.ADDRESSOF) return addressValue(opNode.getArgument(0));
else { // evaluate arguments and call apply
int numArgs = opNode.getNumberOfArguments();
Value[] argValues = new Value[numArgs];
Type type = expr.getInitialType();
for (int i = 0; i < numArgs; i++) {
ExpressionNode arg = opNode.getArgument(i);
Value argValue = evaluate(arg);
argValues[i] = applyConversions(arg, argValue);
}
return apply(type, operator, argValues);
}
} else if (expr instanceof SizeofNode) {
return sizeofValue((((SizeofNode) expr).getArgument()).getType());
} else if (expr instanceof StringLiteralNode) {
return ((StringLiteralNode) expr).getConstantValue();
} else if (expr instanceof EnumerationConstantNode) {
IdentifierNode identNode = ((EnumerationConstantNode) expr).getName();
Entity entity = identNode.getEntity();
if (entity.getEntityKind() == EntityKind.ENUMERATOR) {
return ((Enumerator) entity).getValue();
}
return null;
}
return null;
}
