Changeset 49 for trunk/Target

Timestamp:

Jul 12, 2012, 9:56:58 AM (12 years ago)

Author:

chronos

Message:

• Added: Optimization of sequence [-] in PHP target.

File:

• trunk/Target/UTargetPHP.pas (modified) (4 diffs)

trunk/Target/UTargetPHP.pas

@@ -57 +57 @@
 end;
 
+function CheckClear: Boolean;
+begin
+  Result := (FSourceCode[I] = '[') and (Length(FSourceCode) >= I + 2) and
+    (FSourceCode[I + 1] = '-') and (FSourceCode[I + 2] = ']');
+end;
+
 begin
   inherited;
@@ -66 +72 @@
   AddLine('$Memory = str_repeat("\0", 30000);');
   AddLine('$Position = 0;');
-  for I := 1 to Length(FSourceCode) do begin
+  I := 1;
+  while (I <= Length(FSourceCode)) do begin
     case FSourceCode[I] of
       '>': begin
@@ -87 +94 @@
       ',': AddLine('$Memory[$Position] = fgetc(STDIN);');
       '[': begin
-        AddLine('while($Memory[$Position] != "\0") {');
-        Inc(Indent);
+        if CheckClear then begin
+          AddLine('$Memory[$Position] = "\0";');
+          Inc(I, 2);
+        end else begin
+          AddLine('while($Memory[$Position] != "\0") {');
+          Inc(Indent);
+        end;
       end;
       ']': begin
@@ -95 +107 @@
       end;
     end;
+    Inc(I);
   end;
   AddLine('');