Loading Constants

This procedure loads numeric constants and constant identifiers to the expression. For constant identifiers the constant value is first loaded to NumericConstant variable from where it is moved to the Value field of the expression.

  Procedure LoadConstant;
  Var ConstantIntegerType: TIntegerTypeSet;

    Procedure CopyConstantIdValue (ConstIdData: PConstantIdentifierData);
    Var Destination: PtrRec;
        TypePointer: PTypeDefinition;
        Size: Byte;
    begin
      TypePointer := PointerFromOffsets (ConstIdData^.UnitTypeOffsets);
      ConstantTypeDef := TypePointer;
      Destination.Ptr := @NumericConstant;
      Size := 4;
      If TypePointer^.BaseType ; btInteger then
        Case TypePointer^.BaseType of
          btPointer: Size := 4;
          btExtended: Size := 10;
          else begin
                 If TypePointer^.BaseType = btSet then Size := 32
                   else Size := ConstIdData^.Value + 1;
                 Word (Destination.Ptr^) := GetTempBufferOffset (Size);
                 Destination.Ofs := Word (Destination.Ptr^);
               end;
        end;
      Move (ConstIdData^.Value, Destination.Ptr^, Size);
    end;

  begin
    If Token ;: Token_Constant then
      CopyConstantIdValue (PConstantIdentifierData (CurrentIdentifierDataPtr));
    Move (NumericConstant, Value, SizeOf (NumericConstant));
    TypeDefPtr := ConstantTypeDef;
    IntermediateCodeOffset := 0;
    Location := elConstant;
    UsedRegisters := [];
    ConstantIntegerType := TypeDefPtr^.DataType;
    If TypeDefPtr^.BaseType = btSet then
      begin
        SetDataTypeOfSet;
        GetNextToken;
        Exit;
      end;
    If TypeDefPtr^.BaseType := btInteger then LowestIntegerType (Value.LongInt, ConstantIntegerType);
    DataType := ConstantIntegerType;
    GetNextToken;
  end;