Changeset 185 for branches/virtualcpu4/UAssembler.pas

Timestamp:

May 1, 2019, 9:48:46 PM (6 years ago)

Author:

chronos

Message:

• Added: Assembler labels reference address calculation.
• Fixed: Displaying address/data hex numbers in opcode and instruction.

File:

• branches/virtualcpu4/UAssembler.pas (modified) (10 diffs)

branches/virtualcpu4/UAssembler.pas

@@ -20 +20 @@
     Text: string;
     procedure Expect(Text: string);
+    function IsOperator(C: Char): Boolean;
+    function IsWhiteSpace(C: Char): Boolean;
     function ReadNext: string;
     function EndOfText: Boolean;
@@ -25 +27 @@
   end;
 
+  TLabelRef = class
+    Address: QWord;
+    BitWidth: TBitWidth;
+    Relative: Boolean;
+  end;
+
+  { TLabel }
+
   TLabel = class
     Name: string;
     Address: QWord;
-  end;
+    Refs: TFPGList<TLabelRef>;
+    constructor Create;
+    destructor Destroy; override;
+  end;
+
+  { TLabels }
 
   TLabels = class(TFPGObjecTList<TLabel>)
-
+    function SearchByName(Name: string): TLabel;
   end;
 
@@ -40 +55 @@
     FOnError: TErrorEvent;
     OpcodeDefs: TOpcodeDefs;
+    InstructionIP: QWord;
     procedure Error(Text: string);
     procedure ParseParam(Param: TOpcodeParam);
+    procedure WriteRefAddr(Name: string; Relative: Boolean = False);
+    procedure WriteRefData(Name: string);
+    procedure UpdateLabelRef;
+    procedure ParseInstruction;
   public
     Parser: TParser;
@@ -56 +76 @@
 implementation
 
+{ TLabels }
+
+function TLabels.SearchByName(Name: string): TLabel;
+var
+  I: Integer;
+begin
+  I := 0;
+  while (I < Count) and (Items[I].Name <> Name) do Inc(I);
+  if I < Count then Result := Items[I]
+    else Result := nil;
+end;
+
+{ TLabel }
+
+constructor TLabel.Create;
+begin
+  Refs := TFPGList<TLabelRef>.Create;
+end;
+
+destructor TLabel.Destroy;
+begin
+  Refs.Free;
+  inherited Destroy;
+end;
+
 { TParser }
 
@@ -72 +117 @@
 end;
 
+function TParser.IsOperator(C: Char): Boolean;
+begin
+  Result := (C = ',') or (C = ';');
+end;
+
+function TParser.IsWhiteSpace(C: Char): Boolean;
+begin
+  Result := (C = ' ') or (C = #8);
+end;
+
 function TParser.ReadNext: string;
 var
@@ -78 +133 @@
   Text := Trim(Text);
   P := 1;
-  if (Length(Text) > 0) and (Text[P] = ',') then begin
+  if (Length(Text) > 0) and IsOperator(Text[P]) then begin
     Result := Text[P];
     Delete(Text, 1, 1);
   end else begin
-    while (P <= Length(Text)) and (Text[P] <> ' ') and (Text[P] <> ',') do Inc(P);
+    while (P <= Length(Text)) and not IsWhiteSpace(Text[P]) and not IsOperator(Text[P]) do Inc(P);
     Result := Copy(Text, 1, P - 1);
     Delete(Text, 1, P - 1);
@@ -103 +158 @@
 var
   Reg: TRegIndex;
-  Addr: QWord;
+  Addr: Int64;
   Next: string;
 begin
@@ -115 +170 @@
   if Param = prData then begin
     Next := Parser.ReadNext;
-    InstructionWriter.WriteData(StrToInt(Next));
+    if TryStrToInt64(Next, Addr) then
+      InstructionWriter.WriteData(Addr)
+      else WriteRefData(Next);
   end else
   if Param = prAddr then begin
     Next := Parser.ReadNext;
-    InstructionWriter.WriteAddress(StrToInt(Next));
+    if TryStrToInt64(Next, Addr) then
+      InstructionWriter.WriteAddress(Addr)
+      else WriteRefAddr(Next);
   end else
   if Param = prAddrRel then begin
     Next := Parser.ReadNext;
-    InstructionWriter.WriteAddress(StrToInt(Next));
-  end;
+    if TryStrToInt64(Next, Addr) then
+      InstructionWriter.WriteAddress(InstructionWriter.IP + Addr)
+      else WriteRefAddr(Next, True);
+  end;
+end;
+
+procedure TAssembler.WriteRefAddr(Name: string; Relative: Boolean = False);
+var
+  L: TLabel;
+  NewRef: TLabelRef;
+begin
+  L := Labels.SearchByName(Name);
+  if Assigned(L) then begin
+    if Relative then
+      InstructionWriter.WriteAddressSigned(InstructionWriter.GetRelativeAddr(
+        InstructionWriter.AddrSize, InstructionIP, L.Address))
+      else InstructionWriter.WriteAddress(L.Address);
+  end else begin
+    L := TLabel.Create;
+    L.Name := Name;
+    NewRef := TLabelRef.Create;
+    NewRef.Address := InstructionWriter.IP;
+    NewRef.BitWidth := InstructionWriter.AddrSize;
+    if Relative then NewRef.Relative := True;
+    L.Refs.Add(NewRef);
+    Labels.Add(L);
+    InstructionWriter.WriteAddress(0);
+  end;
+end;
+
+procedure TAssembler.WriteRefData(Name: string);
+var
+  L: TLabel;
+  NewRef: TLabelRef;
+begin
+  L := Labels.SearchByName(Name);
+  if Assigned(L) then begin
+    InstructionWriter.WriteData(L.Address);
+  end else begin
+    L := TLabel.Create;
+    L.Name := Name;
+    NewRef := TLabelRef.Create;
+    NewRef.Address := InstructionWriter.IP;
+    NewRef.BitWidth := InstructionWriter.DataSize;
+    L.Refs.Add(NewRef);
+    Labels.Add(L);
+    InstructionWriter.WriteData(0);
+  end;
+end;
+
+procedure TAssembler.UpdateLabelRef;
+var
+  I: Integer;
+  R: Integer;
+begin
+  for I := 0 to Labels.Count - 1 do
+  with TLabel(Labels[I]) do begin
+    for R := 0 to Refs.Count - 1 do
+    begin
+      InstructionWriter.IP := Refs[R].Address;
+      InstructionWriter.AddrSize := Refs[R].BitWidth;
+      if Refs[R].Relative then InstructionWriter.WriteAddressSigned(InstructionWriter.GetRelativeAddr(
+        InstructionWriter.AddrSize, InstructionWriter.IP - 1, Address))
+        else InstructionWriter.WriteAddress(Address);
+    end;
+  end;
+end;
+
+procedure TAssembler.ParseInstruction;
+var
+  Next: string;
+  LabelName: string;
+  NewLabel: TLabel;
+  OpcodeDef: TOpcodeDef;
+begin
+  Next := Parser.ReadNext;
+  if Next = '' then Exit;
+  if (Length(Next) > 0) and (Next[Length(Next)] = ':') then begin
+    LabelName := Copy(Next, 1, Length(Next) - 1);
+    NewLabel := Labels.SearchByName(LabelName);
+    if not Assigned(NewLabel) then begin
+      NewLabel := TLabel.Create;
+      NewLabel.Name := LabelName;
+      Labels.Add(NewLabel);
+    end;
+    NewLabel.Address := InstructionWriter.IP;
+    Next := Parser.ReadNext;
+  end;
+  if Next = '' then Exit;
+  OpcodeDef := OpcodeDefs.SearchByName(Next);
+  if Assigned(OpcodeDef) then begin
+    if OpcodeDef.Prefix then InstructionWriter.Prefix := True;
+    if OpcodeDef.Opcode = opDataPrefix16 then InstructionWriter.DataSize := bw8
+    else if OpcodeDef.Opcode = opDataPrefix16 then InstructionWriter.DataSize := bw16
+    else if OpcodeDef.Opcode = opDataPrefix32 then InstructionWriter.DataSize := bw32
+    else if OpcodeDef.Opcode = opDataPrefix64 then InstructionWriter.DataSize := bw64
+    else if OpcodeDef.Opcode = opAddrPrefix8 then InstructionWriter.AddrSize := bw8
+    else if OpcodeDef.Opcode = opAddrPrefix16 then InstructionWriter.AddrSize := bw16
+    else if OpcodeDef.Opcode = opAddrPrefix32 then InstructionWriter.AddrSize := bw32
+    else if OpcodeDef.Opcode = opAddrPrefix64 then InstructionWriter.AddrSize := bw64;
+    InstructionIP := InstructionWriter.IP;
+    InstructionWriter.Write8(Byte(OpcodeDef.Opcode));
+    ParseParam(OpcodeDef.Param1);
+    if OpcodeDef.Param2 <> prNone then begin
+      Parser.Expect(',');
+      ParseParam(OpcodeDef.Param2);
+      if OpcodeDef.Param3 <> prNone then begin
+        Parser.Expect(',');
+        ParseParam(OpcodeDef.Param3);
+      end;
+    end;
+    if not OpcodeDef.Prefix then begin
+      InstructionWriter.DataSize := InstructionWriter.DataSizeBase;
+      InstructionWriter.AddrSize := InstructionWriter.AddrSizeBase;
+    end;
+  end else
+  if Next = 'STRING' then begin
+    Next := Parser.ReadNext;
+    if (Length(Next) >= 2) and (Next[1] = '''') and (Next[Length(Next)] = '''') then
+      InstructionWriter.WriteString(Copy(Next, 2, Length(Next) - 2));
+  end else
+  Error('Unknown instruction ' + Next);
 end;
 
@@ -130 +309 @@
 var
   I: Integer;
-  NewLabel: TLabel;
   Next: string;
-  OpcodeDef: TOpcodeDef;
 begin
   InstructionWriter.Init;
@@ -138 +315 @@
   for I := 0 to Source.Count - 1 do begin
     Parser.Text := Source[I];
-    Next := Parser.ReadNext;
-    if (Length(Next) > 0) and (Next[Length(Next)] = ':') then begin
-      NewLabel := TLabel.Create;
-      NewLabel.Name := Copy(Next, 1, Length(Next) - 1);
-      //NewLabel.Address := ;
-      Labels.Add(NewLabel);
+    ParseInstruction;
+    repeat
       Next := Parser.ReadNext;
-    end;
-    OpcodeDef := OpcodeDefs.SearchByName(Next);
-    if Assigned(OpcodeDef) then begin
-      InstructionWriter.Write8(Byte(OpcodeDef.Opcode));
-      ParseParam(OpcodeDef.Param1);
-      if OpcodeDef.Param2 <> prNone then begin
-        Parser.Expect(',');
-        ParseParam(OpcodeDef.Param2);
-        if OpcodeDef.Param3 <> prNone then begin
-          Parser.Expect(',');
-          ParseParam(OpcodeDef.Param3);
-        end;
-      end;
-    end else Error('Unknown instruction ' + Next);
-  end;
+      if (Next = '') or (Next <> ';') then Break;
+      ParseInstruction;
+    until False;
+  end;
+  UpdateLabelRef;
 end;