Implement dup; Update the readme.

libs/squirreljme-class-format/net/multiphasicapps/squirreljme/classformat/StackMapType.java

@@ -70,6 +70,17 @@ public enum StackMapType
 		return this != TOP && this != NOTHING;
 	}
 	
+	/**
+	 * Is this a valid type for storing of a value?
+	 *
+	 * @return {@code true} if this is not nothing or the top type.
+	 * @since 2017/03/31
+	 */
+	public final boolean isValid()
+	{
+		return this != NOTHING && this != TOP;
+	}
+	
 	/**
 	 * Returns {@code true} if this is a wide type.
 	 *

libs/squirreljme-class-format/net/multiphasicapps/squirreljme/classformat/__OpParser__.java

@@ -427,6 +427,10 @@ final class __OpParser__
 			case ClassByteCodeIndex.NEW:
 				return __executeNew(pool.get(input.readUnsignedShort()).
 					<ClassNameSymbol>get(true, ClassNameSymbol.class));
+					
+				// Duplicate variables
+			case ClassByteCodeIndex.DUP:
+				return __executeDup();
 			
 				// {@squirreljme.error AY38 Defined operation cannot be
 				// used in Java ME programs. (The operation)}
@@ -450,7 +454,6 @@ final class __OpParser__
 			case ClassByteCodeIndex.SASTORE:
 			case ClassByteCodeIndex.POP:
 			case ClassByteCodeIndex.POP2:
-			case ClassByteCodeIndex.DUP:
 			case ClassByteCodeIndex.DUP_X1:
 			case ClassByteCodeIndex.DUP_X2:
 			case ClassByteCodeIndex.DUP2:
@@ -556,6 +559,37 @@ final class __OpParser__
 		}
 	}
 	
+	/**
+	 * Duplicates the topmost entry on the stack.
+	 *
+	 * @since 2017/03/31
+	 */
+	private int[] __executeDup()
+	{
+		// Get
+		__SMTState__ smwork = this._smwork;
+		__SMTStack__ stack = smwork._stack;
+		
+		// Get the element on the top of the stack
+		int top = stack.top();
+		StackMapType tt = stack.get(top - 1);
+		
+		// {@squirreljme.error AY0q The specified type cannot be duplicated
+		// on the stack. (The type at the top of the stack)}
+		if (!tt.isValid() || tt.isWide())
+			throw new ClassFormatException(String.format("AY0q %s", tt));
+		
+		// Push this type to the top
+		stack.push(tt);
+		
+		// Generate the copy
+		this.writer.copy(tt, CodeVariable.of(true, top - 1),
+			CodeVariable.of(true, top));
+		
+		// Implicit next
+		return IMPLICIT_NEXT;
+	}
+	
 	/**
 	 * Executes an invoke of a method.
 	 *

readme.mkd

@@ -30,28 +30,32 @@ Note that Java ME 8 has a Java 7 virtual machine with specific limitations.
 ## Repository
 
  * [Online repository](http://multiphasicapps.net/)
-   * SquirrelJME uses `fossil` <http://fossil-scm.org/>.
-   * The repository may be cloned with:
+   ([HTTPS](https://multiphasicapps.net/))
+ * SquirrelJME uses `fossil` <http://fossil-scm.org/>.
+ * The repository may be cloned with:
+   * One of these commands
      * `fossil clone -u http://multiphasicapps.net/ squirreljme.fossil`
-     * `mkdir squireljme`
-     * `cd squirreljme`
-     * `fossil open ../squirreljme.fossil`
-   * Trunk Source Snapshot (`fossil serve` only):
-     * [TAR.GZ](/tarball/squirreljme-trunk.tar.gz?uuid=trunk)
-     * [ZIP](/zip/squirreljme-trunk.zip?uuid=trunk)
-   * Read-Only Mirrors:
-     * Bitbucket: <https://bitbucket.org/mpasteven/squirreljme>
-     * GitHub: <http://github.com/mpasteven/SquirrelJME>
-     * GitLab: <https://gitlab.com/mpasteven/SquirrelJME>
-     * Tor: <http://squirrelzarhffxz.onion/>
-       (`fossil clone -u http://squirrelzarhffxz.onion/ squirreljme.fossil`)
+     * `fossil clone -u https://multiphasicapps.net/ squirreljme.fossil`
+   * `mkdir squireljme`
+   * `cd squirreljme`
+   * `fossil open ../squirreljme.fossil`
+ * Trunk Source Snapshot (`fossil serve` only):
+   * [TAR.GZ](/tarball/squirreljme-trunk.tar.gz?uuid=trunk)
+   * [ZIP](/zip/squirreljme-trunk.zip?uuid=trunk)
+ * Read-Only Mirrors:
+   * Bitbucket: <https://bitbucket.org/mpasteven/squirreljme>
+   * GitHub: <https://github.com/mpasteven/SquirrelJME>
+   * GitLab: <https://gitlab.com/mpasteven/SquirrelJME>
+   * Tor: <http://squirrelzarhffxz.onion/>
+     (`fossil clone -u http://squirrelzarhffxz.onion/ squirreljme.fossil`)
 
 ## Documents
 
  * [Code of Conduct](code-of-conduct.mkd)
  * [Developer Notes](/uv/developer-notes/index.mkd)
    * [Alternative URL](http://multiphasicapps.net/uv/developer-notes/index.mkd)
-     (Links to the main repository)
+     ([HTTPS](https://multiphasicapps.net/uv/developer-notes/index.mkd);
+     Links to the main repository, do not follow via Tor use the direct link)
  * [Manual](assets/manual/index.mkd)
  * [Project Scope](scope.mkd)
  * [Why?](assets/manual/user/why.mkd)