/**
* {@inheritDoc}
*
* <p>Determine the result type of a unary operator.
*
* @param ctx The UnaryOpContext parse tree node
* @return The result type of VOID if not valid.
*/
@Override
public Type visitUnaryop(UnaryopContext ctx) {
String op = ctx.op.getText();
Type rhsType = visit(ctx.expr());
if (rhsType instanceof PrimitiveType) {
switch ((PrimitiveType) rhsType) {
case REAL:
if (op.equals("-") || op.equals("+")) {
typeMap.put(ctx, REAL);
return REAL;
}
error(ctx, op + " cannot be applied to REAL");
break;
case INT:
if (op.equals("-") || op.equals("+") || op.equals("~")) {
typeMap.put(ctx, INT);
return INT;
}
error(ctx, op + " cannot be applied to INT");
break;
case BOOL:
if (op.equals("\00ac")) {
typeMap.put(ctx, BOOL);
return BOOL;
}
error(ctx, op + " cannot be applied to BOOL");
break;
default:
error(ctx, op + " cannot be applied to " + rhsType);
break;
}
}
typeMap.put(ctx, VOID);
return VOID;
}
@Override
public Type visitRecordAccess(MicroParser.RecordAccessContext ctx) {
Type recordType = visit(ctx.expr());
if (recordType instanceof RecordType) {
Scope recordScope = ((RecordType) recordType).getContainedScope();
Identifier id = recordScope.resolve(ctx.ID().getText());
if (id != null) {
Type exprType = id.getType();
typeMap.put(ctx, exprType);
return exprType;
} else {
MicroCompilerV1.error(
ctx,
ctx.ID().getText()
+ " is not a member of "
+ ((RecordType) recordType).getRecordTypeName());
return VOID;
}
} else if (recordType instanceof ArrayType && ctx.ID().getText().equals("length")) {
typeMap.put(ctx, INT);
return INT;
} else {
MicroCompilerV1.error(ctx, "Not a record type");
return VOID;
}
}
/**
* {@inheritDoc}
*
* <p>Determine if the assignment is valid. BOOL and only be assigned to BOOL. INT or REAL can be
* assigned to INT or REAL.
*
* @param ctx The Assignment_Statement Context parse tree node
* @return VOID
*/
@Override
public Type visitAssignment_statement(Assignment_statementContext ctx) {
Type lhsType = visit(ctx.lvalue());
Type rhsType = visit(ctx.expr());
if (!assignmentValid(lhsType, rhsType)) {
MicroCompilerV1.error(ctx, rhsType + " cannot be assigned to " + lhsType);
}
typeMap.put(ctx, VOID);
return VOID;
}
@Override
public Type visitFcnCall(FcnCallContext ctx) {
ctx.expr_list().expr().forEach(expr -> visit(expr));
Identifier fcnId = currentScope.resolve(ctx.ID().getText());
if (fcnId != null) {
Type fcnType = fcnId.getType();
if (fcnType instanceof ProcedureOrFunction) {
Type returnType = ((ProcedureOrFunction) fcnType).getReturnType();
typeMap.put(ctx, returnType);
return returnType;
} else {
MicroCompilerV1.error(ctx, ctx.ID().getText() + " is not a function");
}
} else {
MicroCompilerV1.error(ctx, ctx.ID().getText() + " is not a defined");
}
typeMap.put(ctx, VOID);
return VOID;
}
/**
* {@inheritDoc}
*
* <p>Determine if the while_statement part is valid. The guard expression must be of type BOOL.
*
* @param ctx The If_statement context parse tree node.
* @return VOID
*/
@Override
public Type visitWhile_statement(While_statementContext ctx) {
Type guardType = visit(ctx.expr());
if (guardType != BOOL) {
error(ctx, "While statement guard is not a boolean type");
}
visit(ctx.statement_list());
typeMap.put(ctx, VOID);
return VOID;
}
/**
* {@inheritDoc}
*
* <p>The default implementation returns the result of calling {@link #visitChildren} on {@code
* ctx}.
*/
@Override
public Type visitIdLvalue(IdLvalueContext ctx) {
Identifier id = currentScope.resolve(ctx.ID().getText());
if (id == null) {
MicroCompilerV1.error(ctx, ctx.ID().getText() + " is not defined");
return VOID;
}
Type lhsType = id.getType();
typeMap.put(ctx, lhsType);
return lhsType;
}
/**
* {@inheritDoc}
*
* <p>Determine the type of an ID
*
* @param ctx The parse tree node.
* @return The type of the identifier.
*/
@Override
public Type visitId(IdContext ctx) {
String idName = ctx.ID().getText();
Identifier id = currentScope.resolve(idName);
if (id != null) {
typeMap.put(ctx, id.getType());
return id.getType();
}
error(ctx, "Undefined identifier " + idName);
typeMap.put(ctx, VOID);
return VOID;
}
/**
* {@inheritDoc}
*
* <p>Determine result type of logical op. Both operands must be BOOL
*
* @param ctx LogicalopContext node.
* @return BOOL if valid, VOID otherwise
*/
@Override
public Type visitLogicalop(LogicalopContext ctx) {
Type lhsType = visit(ctx.expr(0));
Type rhsType = visit(ctx.expr(1));
if (BOOL == lhsType && BOOL == rhsType) {
typeMap.put(ctx, BOOL);
return BOOL;
}
error(ctx, lhsType + " cannot be combined using a logical operator with " + rhsType);
typeMap.put(ctx, VOID);
return VOID;
}
/**
* {@inheritDoc}
*
* <p>The default implementation returns the result of calling {@link #visitChildren} on {@code
* ctx}.
*/
@Override
public Type visitArrayAccess(MicroParser.ArrayAccessContext ctx) {
Type arrayType = visit(ctx.expr(0));
if (arrayType instanceof ArrayType) {
Type exprType = ((ArrayType) arrayType).getComponentType();
typeMap.put(ctx, exprType);
return exprType;
} else {
MicroCompilerV1.error(ctx, "Not an array type");
return VOID;
}
}
/**
* {@inheritDoc}
*
* <p>Determine if the if statement is valid. The guard expression must be of type BOOL.
*
* @param ctx The If_statement context parse tree node.
* @return VOID
*/
@Override
public Type visitIf_statement(If_statementContext ctx) {
Type guardType = visit(ctx.expr());
if (guardType != BOOL) {
error(ctx, "If statement guard is not a boolean type");
}
visit(ctx.statement_list());
ctx.elsif_part().forEach(elsif_part -> visit(elsif_part));
if (ctx.else_part() != null) {
visit(ctx.else_part());
}
typeMap.put(ctx, VOID);
return VOID;
}
/**
* {@inheritDoc}
*
* <p>Determine the result type of a POW expression.
*
* @param ctx The POW op context parse tree node
* @return The result type or VOID if invalid.
*/
@Override
public Type visitPowop(PowopContext ctx) {
Type lhsType = visit(ctx.expr(0));
Type rhsType = visit(ctx.expr(1));
Type resultType;
if (lhsType == CHAR || rhsType == CHAR) {
resultType = VOID;
} else {
resultType = determineExpressionResult(lhsType, rhsType);
}
if (VOID == resultType) {
error(ctx, lhsType + " ** " + rhsType + " is not valid");
}
typeMap.put(ctx, resultType);
return resultType;
}
/**
* {@inheritDoc}
*
* <p>Determine the result type of an arithmetic expression.
*
* @param ctx The parse tree node.
* @return The result type or VOID if invalid.
*/
@Override
public Type visitArithop(ArithopContext ctx) {
Type lhsType = visit(ctx.expr(0));
Type rhsType = visit(ctx.expr(1));
Type resultType;
String op = ctx.op.getText();
if (lhsType == CHAR || rhsType == CHAR) {
switch (op) {
case "+":
if ((lhsType == CHAR && rhsType == INT) || (rhsType == CHAR && lhsType == INT)) {
resultType = CHAR;
} else {
resultType = VOID;
}
break;
case "-":
if (lhsType == CHAR && rhsType == CHAR) {
resultType = INT;
} else if (lhsType == CHAR && rhsType == INT) {
resultType = CHAR;
} else {
resultType = VOID;
}
break;
default:
resultType = VOID;
break;
}
} else {
resultType = determineExpressionResult(lhsType, rhsType);
}
if (VOID == resultType) {
error(ctx, lhsType + " " + op + " " + rhsType + " is not a valid combination");
}
typeMap.put(ctx, resultType);
return resultType;
}
