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package ast.nodes;
import java.util.ArrayList;
import java.util.HashMap;
import semanticanalysis.STentry;
import semanticanalysis.SemanticError;
import semanticanalysis.SymbolTable;
import ast.types.*;
import org.antlr.v4.runtime.tree.TerminalNode;
import codegen.Label;
/**
* Node for the `funcdef` statement of the grammar.
*/
public class FuncdefNode implements Node {
private final TerminalNode name;
private final Node paramlist;
private final Node block;
private final String funLabel;
public FuncdefNode(TerminalNode name, Node paramlist, Node block) {
this.name = name;
this.paramlist = paramlist;
this.block = block;
this.funLabel = Label.newFun("FUN");
}
@Override
public ArrayList<SemanticError> checkSemantics(SymbolTable ST, int _nesting, FunctionType ft) {
ArrayList<SemanticError> errors = new ArrayList<>();
int paramNumber = 0;
if (paramlist != null) {
paramNumber = ((ParamlistNode) paramlist).getParamNumber();
}
Type returnType = this.block.typeCheck();
FunctionType newFt = new FunctionType(paramNumber, returnType, funLabel);
String funName = this.name.toString();
ST.insert(funName, newFt, _nesting, "");
HashMap<String, STentry> HM = new HashMap<>();
ST.add(HM);
ST.insert(funName, newFt, _nesting + 1, "");
ST.decreaseOffset();
if (paramlist != null) {
errors.addAll(paramlist.checkSemantics(ST, _nesting + 1, newFt));
}
// Offset is increased for the possible return value
ST.increaseOffset();
errors.addAll(block.checkSemantics(ST, _nesting + 1, newFt));
// return to the outer block
ST.remove();
return errors;
}
// FIXME: this type must be the same of the return stmt variable
@Override
public Type typeCheck() {
return new VoidType();
}
/**
* Taken from slide 56 of CodeGeneration.pdf
*/
@Override
public String codeGeneration() {
String blockS = block.codeGeneration();
// The "return" which fix the RA is inside the block
String funS = funLabel + ":\n" +
"pushr RA\n" +
blockS;
Label.addFunDef(funS);
return "";
}
@Override
public String toPrint(String prefix) {
String str = prefix + "Funcdef(" + name + ")\n";
prefix += " ";
if (paramlist != null) {
str += paramlist.toPrint(prefix);
}
str += block.toPrint(prefix);
return str;
}
}
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