Changeset 18

Timestamp:

Apr 9, 2009, 11:17:38 AM (15 years ago)

Author:

george

Message:

• Upraveno: Vylepšené parsování.

Files:

• doc (added)
• doc/skripta překladače.pdf (added)
• trunk/Example.pas (modified) (1 diff)
• trunk/UMainForm.pas (modified) (29 diffs)

trunk/Example.pas

@@ -1 +1 @@
 program Test;
 var
-  A: Byte;
+  a: Byte;
+  B: Byte;
 begin
-  A := 'a' + (10 + 2) * 3 xor 10 / 2;
+  A := 'a' + (10 + 2 * 3 + 2) xor 10 / 2;
+  B := 20;
   while A < 10 do A := A + 1;
+
 end;

trunk/UMainForm.pas

@@ -12 +12 @@
   TModuleType = (mdProgram, mdUnit, mdLibrary, mdPackage);
 
-  TInstruction = (inJump, inConditionalJump, inExpressionEvaluation);
-
-  TNodeType = (ntNone, ntVariable, ntMethod, ntConstant, ntOperator);
+  TInstruction = (inNone, inJump, inConditionalJump, inExpressionEvaluation,
+    inReturn);
+
+  TNodeType = (ntNone, ntVariable, nTFunction, ntConstant, ntOperator);
 
   TValue = array of Byte;
@@ -23 +24 @@
   TConstantList = class;
   TVariableList = class;
-  TMethodList = class;
+  TFunctionList = class;
   TExpression = class;
   TOperationList = class;
+  TFunction = class;
 
   TDevice = class
@@ -38 +40 @@
     Types: TTypeList;
     Variables: TVariableList;
-    Methods: TMethodList;
+    Methods: TFunctionList;
     Operations: TOperationList;
     procedure AllocateMemory;
@@ -48 +50 @@
     procedure ParseOperation(Compiler: TCompiler);
     procedure GenerateAssembler(Compiler: TCompiler; LabelPrefix: string);
+    procedure CheckReferences;
   end;
 
@@ -93 +96 @@
     NodeType: TNodeType;
     Variable: TVariable;
-    Method: TMethod;
+    Method: TFunction;
     Value: TValue;
     OperatorName: string;
@@ -108 +111 @@
     GotoAddress: Integer;
     Negative: Boolean;
+    Referenced: Boolean;
   end;
 
@@ -114 +118 @@
   end;
 
-  TMethod = class(TCommonBlock)
+  TFunction = class(TCommonBlock)
     Parameters: TList; // TList<TParameter>
     ResultType: TType;
@@ -122 +126 @@
   end;
 
-  TMethodList = class(TList)
+  TFunctionList = class(TList)
     Parent: TCommonBlock;
     procedure Parse(Compiler: TCompiler);
-    function Search(Name: string): TMethod;
+    function Search(Name: string): TFunction;
   end;
 
@@ -137 +141 @@
     procedure ParseUnit(Compiler: TCompiler);
     procedure ParseProgram(Compiler: TCompiler);
+    procedure Clear;
   end;
 
@@ -275 +280 @@
   ProgramCode.Parse(Self);
   ProgramCode.AllocateMemory;
+  AssemblyCode.Clear;
   GenerateAssemblyCode;
 end;
@@ -438 +444 @@
 end;
 
-{ TMethod }
-
-constructor TMethod.Create;
+{ TFunction }
+
+constructor TFunction.Create;
 begin
   inherited;
@@ -447 +453 @@
 end;
 
-destructor TMethod.Destroy;
+destructor TFunction.Destroy;
 begin
   Parameters.Free;
@@ -454 +460 @@
 end;
 
-procedure TMethod.Parse(Compiler: TCompiler);
+procedure TFunction.Parse(Compiler: TCompiler);
 begin
   with Compiler do begin
@@ -478 +484 @@
   Device := TDevice.Create;
   Modules := TList.Create;
+end;
+
+destructor TProgram.Destroy;
+begin
+
+end;
+
+procedure TProgram.GenerateAssembler(Compiler: TCompiler);
+var
+  I: Integer;
+begin
+  for I := 0 to Modules.Count - 1 do
+    TModule(Modules[I]).GenerateAssembler(Compiler, '');
+end;
+
+procedure TProgram.Parse(Compiler: TCompiler);
+var
+  I: Integer;
+begin
+  for I := 0 to Modules.Count - 1 do
+    TModule(Modules[I]).Clear;
+  Modules.Clear;
   with TModule(Modules[Modules.Add(TModule.Create)]) do begin
     Name := 'main';
@@ -486 +514 @@
     end;
   end;
-end;
-
-destructor TProgram.Destroy;
-begin
-
-end;
-
-procedure TProgram.GenerateAssembler(Compiler: TCompiler);
-var
-  I: Integer;
-begin
-  for I := 0 to Modules.Count - 1 do
-    TModule(Modules[I]).GenerateAssembler(Compiler, '');
-end;
-
-procedure TProgram.Parse(Compiler: TCompiler);
-begin
   TModule(Modules[0]).Parse(Compiler);
 end;
@@ -537 +548 @@
 
 { TModule }
+
+procedure TModule.Clear;
+begin
+  Variables.Clear;
+  Constants.Clear;
+  Methods.Clear;
+  Operations.Clear;
+end;
 
 constructor TModule.Create;
@@ -589 +608 @@
 end;
 
+procedure TCommonBlock.CheckReferences;
+var
+  I: Integer;
+begin
+  for I := 0 to Operations.Count - 1 do
+  with TOperation(Operations[I]) do begin
+    if (Instruction = inJump) or (Instruction = inConditionalJump) then
+      TOperation(Operations[GotoAddress]).Referenced := True;
+  end;
+end;
+
 constructor TCommonBlock.Create;
 begin
@@ -597 +627 @@
   Variables := TVariableList.Create;
   Variables.Parent := Self;
-  Methods := TMethodList.Create;
+  Methods := TFunctionList.Create;
   Methods.Parent := Self;
   Operations := TOperationList.Create;
@@ -615 +645 @@
 var
   I: Integer;
+  LabelName: string;
 begin
   with Compiler do
-  for I := 0 to Operations.Count - 1 do
+  for I := 0 to Operations.Count - 1 do 
   with TOperation(Operations[I]) do begin
+    if Referenced then LabelName := Name + '_L' + IntToStr(I)
+      else LabelName := '';
     case Instruction of
       inJump: begin
-        AddInstruction('', 'JMP', Name + '_L' + IntToStr(GotoAddress), '');
+        AddInstruction(LabelName, 'JMP', Name + '_L' + IntToStr(GotoAddress), '');
       end;
       inConditionalJump: begin
         ExpressionTree.GenerateAssembler(Compiler, LabelPrefix + '_L' + IntToStr(GotoAddress));
-        AddInstruction('', 'BRCS', Name + '_L' + IntToStr(GotoAddress), '');
+        AddInstruction(LabelName, 'BRCS', Name + '_L' + IntToStr(GotoAddress), '');
       end;
       inExpressionEvaluation: begin
+        if LabelName <> '' then AddInstruction(LabelName, '', '', '');
         ExpressionTree.GenerateAssembler(Compiler, Name + '_L' + IntToStr(GotoAddress));
       end;
+      inReturn:
+        AddInstruction(LabelName, 'RET', '', '');
     end;
   end;
@@ -652 +688 @@
 var
   Identifier: string;
-  Variable: TVariable;
-  Method: TMethod;
+  NewVariable: TVariable;
+  Method: TFunction;
   Constant: TConstant;
 //  Brackets: Integer;
@@ -680 +716 @@
         end else
         if IsIdentificator(Identifier) then begin
-          Variable := Variables.Search(Identifier);
-          if Assigned(Variable) then begin
+          NewVariable := Variables.Search(Identifier);
+          if Assigned(NewVariable) then begin
             with TExpression(Expressions[Expressions.Count - 1]) do begin
               SubItems[1] := TExpression.Create;
               TExpression(SubItems[1]).NodeType := ntVariable;
-              TExpression(SubItems[1]).Variable := Variable;
+              TExpression(SubItems[1]).Variable := NewVariable;
             end;
             with TExpression(Expressions.Items[Expressions.Add(TExpression.Create)]) do begin
@@ -705 +741 @@
                   Expect(')');
                 end;
-                TExpression(SubItems[1]).NodeType := ntMethod;
+                TExpression(SubItems[1]).NodeType := nTFunction;
                 TExpression(SubItems[1]).Method := Method;
               end;
@@ -722 +758 @@
                   SubItems[0] := TExpression(Expressions[Expressions.Count - 2]).SubItems[1];
                 end;
+              end else begin
+                ErrorMessage('Neznámý identifikátor: ' + Identifier);
               end;
             end;
@@ -769 +807 @@
   Identifier: string;
   Variable: TVariable;
-  Method: TMethod;
+  Method: TFunction;
   First: TOperation;
   Second: TOperation;
@@ -909 +947 @@
     end;
     Expect('end');
-  end;
+    with TOperation(Operations[Operations.Add(TOperation.Create)]) do begin
+      Instruction := inReturn;
+    end;
+  end;
+  CheckReferences;
 end;
 
@@ -1010 +1052 @@
 end;
 
-{ TMethodList }
-
-procedure TMethodList.Parse(Compiler: TCompiler);
-begin
-
-end;
-
-function TMethodList.Search(Name: string): TMethod;
+{ TFunctionList }
+
+procedure TFunctionList.Parse(Compiler: TCompiler);
+begin
+
+end;
+
+function TFunctionList.Search(Name: string): TFunction;
 var
   I: Integer;
 begin
   I := 0;
-  while (I < Count) and (TMethod(Items[I]).Name <> Name) do Inc(I);
+  while (I < Count) and (TFunction(Items[I]).Name <> Name) do Inc(I);
   if I < Count then Result := Items[I] else begin
     if Assigned(Parent.Parent) then Result := Parent.Parent.Methods.Search(Name)
@@ -1045 +1087 @@
 end;
 
-procedure TExpression.GenerateAssembler(Compiler: TCompiler;
-  LabelPrefix: string);
+procedure TExpression.GenerateAssembler(Compiler: TCompiler; LabelPrefix: string);
 var
   I: Integer;
@@ -1053 +1094 @@
   case NodeType of
     ntNone: ;
-    ntVariable: AddInstruction('', 'CALL', '', '');
-    ntMethod: AddInstruction('', 'CALL', '', '');
+    ntVariable: if Assigned(Variable) then AddInstruction('', 'GETVAR', Variable.Name, '');
+    nTFunction: AddInstruction('', 'CALL', Method.Name, '');
     ntConstant: AddInstruction('', 'CONST', '', '');
     ntOperator: begin
@@ -1084 +1125 @@
 function TAssemblerLine.AsString: string;
 begin
-  Result := LabelName + ': ' + Instruction + ' ' + Operand1 + ',' + Operand2;
+  if LabelName = '' then LabelName := #9 else
+    LabelName := LabelName + ':'#9;
+  if Operand2 <> '' then Operand1 := Operand1 + ', ';
+  
+  Result := LabelName + Instruction + ' ' + Operand1 + Operand2;
 end;