VarType TypeCheckerVisitor::getOperationResultType(TokenKind tokenKind, AstNode* left, AstNode* right) {
VarType result = VT_INVALID;
VarType leftType = getNodeType(left);
VarType rightType = getNodeType(right);
switch (tokenKind) {
case tOR: case tAND: case tEQ: case tNEQ:
case tGT: case tGE: case tLT: case tLE:
result = VT_INT;
break;
case tADD:
if (leftType == VT_STRING || rightType == VT_STRING) {
result = VT_STRING;
} else if (leftType == VT_DOUBLE || rightType == VT_DOUBLE) {
result = VT_DOUBLE;
} else if (leftType == VT_INT && rightType == VT_INT) {
result = VT_INT;
}
break;
case tSUB: case tMUL: case tDIV: case tMOD:
if (leftType == VT_DOUBLE || rightType == VT_DOUBLE) {
result = VT_DOUBLE;
} else if (leftType == VT_INT && rightType == VT_INT) {
result = VT_INT;
}
break;
case tASSIGN:
if (!(isAssignable(leftType, rightType))) {
setErrorMessage(right, "bad type");
}
result = leftType;
break;
case tDECRSET:
if (!(isAssignable(leftType, rightType)) || (leftType == VT_STRING)) {
setErrorMessage(right, "bad type");
}
result = leftType;
break;
case tINCRSET:
if (leftType == VT_STRING) {
result = VT_STRING;
} else if (leftType == VT_DOUBLE) {
result = VT_DOUBLE;
} else if (leftType == VT_INT && rightType == VT_INT) {
result = VT_INT;
}
break;
default:
assert(0);
}
if (leftType == VT_VOID) {
setErrorMessage(left, "Should not be of type void");
}
if (rightType == VT_VOID) {
setErrorMessage(right, "Should not be of type void");
}
return result;
}
void TypeCheckerVisitor::visitStoreNode(StoreNode* node) {
AstNode* value = node->value();
value->visit(this);
const AstVar* var = node->var();
if (isAssignable(var->type(), getNodeType(value))) {
setNodeType(node, var->type());
} else {
setErrorMessage(node, "Bad type");
}
}
static void typeAssign(Output& output, Ast::Assign* n, TypeConstraints* constraints)
{
type(output, n->left, constraints);
type(output, n->right, constraints);
typeMustEqual(n->right, astType(n->left), constraints, output);
if (!isAssignable(n->left) && !constraints)
output.error(n->location, "Expression is not assignable");
if (!n->type)
n->type = UNION_NEW(Ty, Void, {});
}
static bool isAssignable(Ast* node)
{
if (UNION_CASE(Ident, n, node))
return n->targets.size == 1 && n->targets[0]->kind == Variable::KindVariable;
else if (UNION_CASE(Member, n, node))
return isAssignable(n->expr);
else if (UNION_CASE(Index, n, node))
return true;
else if (UNION_CASE(Unary, n, node))
return n->op == UnaryOpDeref;
else
return false;
}
void TypeCheckerVisitor::visitCallNode(CallNode* node) {
uint32_t params_count = node->parametersNumber();
AstFunction* refFunc = _current_scope->lookupFunction(node->name(), true);
bool matchesRefedFunction = (refFunc!= NULL) && (refFunc->parametersNumber() == params_count);
for (uint32_t i = 0; i < params_count; i++) {
AstNode* param = node->parameterAt(i);
param->visit(this);
if (matchesRefedFunction && !isAssignable(refFunc->parameterType(i), getNodeType(param))) {
setErrorMessage(param, "Wrong type parameter");
}
}
if (matchesRefedFunction) {
setNodeType(node, refFunc->returnType());
} else {
setNodeType(node, VT_INVALID);
}
}
void TypeCheckerVisitor::visitFunctionNode(FunctionNode* node) {
node->body()->visit(this);
if (!isAssignable(node->returnType(), getNodeType(node->body()))) {
setNodeType(node, VT_INVALID);
}
}