void Semantic::traverse(Decl * cur) {
if (cur->v == Decl::STRUCT_T) {
newSym(sid, Symbol(cur->ID, cur)); //declared but not defined
pre = false;
}
else if (cur->v == Decl::FUNC_T) {
newSym(vid.back(), Symbol(cur->ID, cur)); //declared but not defined
pre = false;
}
else if (cur->v == Decl::USE_LIT_T) {
if (!pre) error("#use directives must all be on the top");
//check if cur->ID file exists, parse it, cur parent gets this progitem appended
}
else if (cur->v == Decl::USE_LIB_T) {
if (!pre) error("#use directives must all be on the top");
//check if cur->ID file exists whithin include path, parse it, cur parent gets this progitem appended
}
}
void Semantic::traverse(Defn * cur) {
if (cur->v == Defn::STRUCT_T) {
newSym(sid, Symbol(cur->id, cur));
//check struct types and names pairwise to be distinct
ArgItem * ptr = cur->args;
std::set<std::string> ids;
while (ptr != NULL) {
valSctType(ptr->arg->type);
if (ids.find(ptr->arg->ID) != ids.end())
error("struct field names must be pairwise distinct");
ptr = ptr->next;
}
}
else if (cur->v == Defn::FUNC_T) {
//check ret type
valRetType(cur->type);
newSym(vid.back(), Symbol(cur->id, cur));
curF = cur->id;
pushScope();
//check args types and names
ArgItem * ptr = cur->args;
std::set<std::string> ids;
while (ptr != NULL) {
valArgType(ptr->arg->type);
newSym(vid.back(), Symbol(ptr->arg->ID, cur->type));
if (ids.find(ptr->arg->ID) != ids.end())
error("argument names must be pairwise distinct");
ptr = ptr->next;
}
pushScope();
traverse(cur->stmts);
popScope();
popScope();
curF = "";
}
else if (cur->v == Defn::TYPEDEF_T) {
valArgType(cur->type);
newSym(aid, Symbol(cur->id, cur));
}
}
Table *check(Absyn * program, boolean showSymbolTables)
{
Table *globalTable;
Entry *e;
globalTable = newTable(NULL);
if (showSymbolTables) {
local_debug = TRUE;
}
/* generate built-in types */
builtinType_int = newPrimitiveType("int", INT_BYTE_SIZE);
builtinType_bool = newPrimitiveType("bool", BOOL_BYTE_SIZE);
Entry *builtinProc_exit =
newProcEntry(emptyParamTypes(), newTable(globalTable), NULL);
Entry *builtinProc_time =
newProcEntry(newParamTypes
(builtinType_int, TRUE, emptyParamTypes()),
newTable(globalTable), NULL);
Entry *builtinProc_readi =
newProcEntry(newParamTypes
(builtinType_int, TRUE, emptyParamTypes()),
newTable(globalTable), NULL);
Entry *builtinProc_readc =
newProcEntry(newParamTypes
(builtinType_int, TRUE, emptyParamTypes()),
newTable(globalTable), NULL);
Entry *builtinProc_printi =
newProcEntry(newParamTypes
(builtinType_int, FALSE, emptyParamTypes()),
newTable(globalTable), NULL);
Entry *builtinProc_printc =
newProcEntry(newParamTypes
(builtinType_int, FALSE, emptyParamTypes()),
newTable(globalTable), NULL);
Entry *builtinProc_clearAll =
newProcEntry(newParamTypes
(builtinType_int, FALSE, emptyParamTypes()),
newTable(globalTable), NULL);
Entry *builtinProc_setPixel =
newProcEntry(newParamTypes(builtinType_int, FALSE,
newParamTypes(builtinType_int, FALSE,
newParamTypes
(builtinType_int, FALSE,
emptyParamTypes()))),
newTable(globalTable), NULL);
Entry *builtinProc_drawCircle =
newProcEntry(newParamTypes(builtinType_int, FALSE,
newParamTypes(builtinType_int, FALSE,
newParamTypes
(builtinType_int, FALSE,
newParamTypes
(builtinType_int, FALSE,
emptyParamTypes())))),
newTable(globalTable), NULL);
Entry *builtinProc_drawLine =
newProcEntry(newParamTypes(builtinType_int, FALSE,
newParamTypes(builtinType_int, FALSE,
newParamTypes
(builtinType_int, FALSE,
newParamTypes
(builtinType_int, FALSE,
newParamTypes
(builtinType_int, FALSE,
emptyParamTypes()))))),
newTable(globalTable), NULL);
/* setup global symbol table */
enter(globalTable, newSym("int"), newTypeEntry(builtinType_int));
enter(globalTable, newSym("exit"), builtinProc_exit);
enter(globalTable, newSym("time"), builtinProc_time);
enter(globalTable, newSym("readi"), builtinProc_readi);
enter(globalTable, newSym("readc"), builtinProc_readc);
enter(globalTable, newSym("printi"), builtinProc_printi);
enter(globalTable, newSym("printc"), builtinProc_printc);
enter(globalTable, newSym("clearAll"), builtinProc_clearAll);
enter(globalTable, newSym("setPixel"), builtinProc_setPixel);
enter(globalTable, newSym("drawCircle"), builtinProc_drawCircle);
enter(globalTable, newSym("drawLine"), builtinProc_drawLine);
/* enter all procs into global symtable */
enter_proc_decs(program, globalTable);
/* do semantic checks */
checkNode(program, globalTable);
/* check if "main()" is present */
e = lookup(globalTable, newSym("main"));
if (e == NULL)
error("procedure 'main' is missing");
if (e->kind != ENTRY_KIND_PROC)
error("'main' is not a procedure");
// check that main has no params
if (!e->u.procEntry.paramTypes->isEmpty)
error("procedure 'main' must not have any parameters");
/* return global symbol table */
return globalTable;
}
void Semantic::traverse(Stmt * cur) {
if (cur->v == Stmt::LIST_T) {
pushScope();
traverse(cur->list);
popScope();
}
else if (cur->v == Stmt::IF_T || cur->v == Stmt::WHILE_T) {
if (cur->v == Stmt::WHILE_T) loops.push(cur);
Type t = expType(cur->exp);
traverse(cur->exp);
if (t.v == Type::INT_T || t.v == Type::CHAR_T) {
//warning
pushScope();
traverse(cur->left);
popScope();
}
else if (t.v == Type::BOOL_T) {
pushScope();
traverse(cur->left);
popScope();
}
else
error("Condition must be of type bool");
if (cur->v == Stmt::WHILE_T) loops.pop();
}
else if (cur->v == Stmt::FOR_T) {
loops.push(cur);
pushScope();
traverse(cur->left);
Type t = expType(cur->exp);
traverse(cur->exp);
if (t.v == Type::INT_T || t.v == Type::CHAR_T) {
//warning
pushScope();
traverse(cur->stmt);
popScope();
}
else if (t.v == Type::BOOL_T) {
pushScope();
traverse(cur->stmt);
popScope();
}
else
error("Condition must be of type bool");
if (hasDecl(cur->right))
error("For loop-end statement must not include declarations");
traverse(cur->right);
popScope();
loops.pop();
}
else if (cur->v == Stmt::RETURN_T) {
//check current function return type and compare it with this
if (!sameType(expType(cur->exp), *getSym(curF).defn->type))
error("return expression type differs from function " + curF + " signature");
if (cur->exp != NULL)
traverse(cur->exp);
}
else if (cur->v == Stmt::ASSERT_T) {
//check argument type to be of bool
if (!sameType(expType(cur->exp), Type(Type::BOOL_T)))
error("assert expression type must be bool");
traverse(cur->exp);
}
else if (cur->v == Stmt::ERROR_T) {
//call error function with argment string
if (!sameType(expType(cur->exp), Type(Type::STRING_T)))
error("error argument must be of type string");
traverse(cur->exp);
}
else if (cur->v == Stmt::ASSIGN_T) {
//check if lhs and rhs same type, ensure rhs and lhs is not a struct
Type l = lvalType(cur->lval), r = expType(cur->exp);
traverse(cur->exp);
if (cur->op == "=") {
if (!sameType(l, r))
error("lval and expression have different types");
}
else if (cur->op == ">>=") {
if (!(sameType(l, Type(Type::INT_T)) || sameType(l, Type(Type::CHAR_T))))
error("lval from right shift must be of type int or char");
if (!sameType(r, Type(Type::INT_T)))
error("shift ammount must be of type int");
}
else if (cur->op == "<<=") {
if (!(sameType(l, Type(Type::INT_T)) || sameType(l, Type(Type::CHAR_T))))
error("lval from left shift must be of type int or char");
if (!sameType(r, Type(Type::INT_T)))
error("shift ammount must be of type int");
}
else if (cur->op == "+=") {
if (!(sameType(l, Type(Type::INT_T)) || sameType(l, Type(Type::CHAR_T))))
error("lval from add assign must be of type int or char");
if (!(sameType(r, Type(Type::INT_T)) || sameType(r, Type(Type::CHAR_T))))
error("expression from add assign must be of type int or char");
}
else if (cur->op == "-=") {
if (!(sameType(l, Type(Type::INT_T)) || sameType(l, Type(Type::CHAR_T))))
error("lval from sub assign must be of type int or char");
if (!(sameType(r, Type(Type::INT_T)) || sameType(r, Type(Type::CHAR_T))))
error("expression from sub assign must be of type int or char");
}
else if (cur->op == "*=") {
if (!(sameType(l, Type(Type::INT_T)) || sameType(l, Type(Type::CHAR_T))))
error("lval from mul assign must be of type int or char");
if (!(sameType(r, Type(Type::INT_T)) || sameType(r, Type(Type::CHAR_T))))
error("expression from mul assign must be of type int or char");
}
else if (cur->op == "/=") {
if (!(sameType(l, Type(Type::INT_T)) || sameType(l, Type(Type::CHAR_T))))
error("lval from div assign must be of type int or char");
if (!(sameType(r, Type(Type::INT_T)) || sameType(r, Type(Type::CHAR_T))))
error("expression from div assign must be of type int or char");
}
else if (cur->op == "%=") {
if (!(sameType(l, Type(Type::INT_T)) || sameType(l, Type(Type::CHAR_T))))
error("lval from mod assign must be of type int or char");
if (!(sameType(r, Type(Type::INT_T)) || sameType(r, Type(Type::CHAR_T))))
error("expression from mod assign must be of type int or char");
}
else if (cur->op == "&=") {
if (!(sameType(l, Type(Type::INT_T)) || sameType(l, Type(Type::CHAR_T)) || sameType(l, Type(Type::BOOL_T))))
error("lval from and assign must be of type int or char or bool");
if (!(sameType(r, Type(Type::INT_T)) || sameType(r, Type(Type::CHAR_T)) || sameType(r, Type(Type::BOOL_T))))
error("expression from and assign must be of type int or char or bool");
}
else if (cur->op == "^=") {
if (!(sameType(l, Type(Type::INT_T)) || sameType(l, Type(Type::CHAR_T)) || sameType(l, Type(Type::BOOL_T))))
error("lval from xor assign must be of type int or char or bool");
if (!(sameType(r, Type(Type::INT_T)) || sameType(r, Type(Type::CHAR_T)) || sameType(r, Type(Type::BOOL_T))))
error("expression from xor assign must be of type int or char or bool");
}
else if (cur->op == "|=") {
if (!(sameType(l, Type(Type::INT_T)) || sameType(l, Type(Type::CHAR_T)) || sameType(l, Type(Type::BOOL_T))))
error("lval from or assign must be of type int or char or bool");
if (!(sameType(r, Type(Type::INT_T)) || sameType(r, Type(Type::CHAR_T)) || sameType(r, Type(Type::BOOL_T))))
error("expression from or assign must be of type int or char or bool");
}
}
else if (cur->v == Stmt::INC_T) {
//check if lhs is int or char
Type l = lvalType(cur->lval);
if (!(sameType(l, Type(Type::INT_T)) || sameType(l, Type(Type::CHAR_T))))
error("lval from increment must be of type int or char");
}
else if (cur->v == Stmt::DEC_T) {
//check if lhs is int or char
Type l = lvalType(cur->lval);
if (!(sameType(l, Type(Type::INT_T)) || sameType(l, Type(Type::CHAR_T))))
error("lval from decrement must be of type int or char");
}
else if (cur->v == Stmt::EXP_T) {
traverse(cur->exp);
}
else if (cur->v == Stmt::DECL_T) {
//declaring a variable
newSym(vid.back(), Symbol(cur->arg->ID, cur->arg->type));
}
else if (cur->v == Stmt::DECLI_T) {
//declaring and assigning a variable
newSym(vid.back(), Symbol(cur->arg->ID, cur->arg->type));
}
else if (cur->v == Stmt::BREAK_T) {
//check most recent loop
if (loops.empty())
error("break statement does not have a loop");
}
else if (cur->v == Stmt::CONT_T) {
if (loops.empty())
error("continue statement does not have a loop");
}
}