optimization: use tags not gens. improves memory (create less garbage), faster (dont need to transform the garbage): see pr128650, optimization #6.

4 files changed, 224 insertions, 22 deletions

diff --git a/bcel-builder/src/org/aspectj/apache/bcel/generic/LineNumberTag.java b/bcel-builder/src/org/aspectj/apache/bcel/generic/LineNumberTag.java
new file mode 100644
index 000000000..b8136de35
--- /dev/null
+++ b/bcel-builder/src/org/aspectj/apache/bcel/generic/LineNumberTag.java
@@ -0,0 +1,40 @@
+/* *******************************************************************
+ * Copyright (c) 2002 Contributors
+ * All rights reserved. 
+ * This program and the accompanying materials are made available 
+ * under the terms of the Common Public License v1.0 
+ * which accompanies this distribution and is available at 
+ * http://www.eclipse.org/legal/cpl-v10.html 
+ *  
+ * Contributors: 
+ *     PARC         initial implementation 
+ *   Andy Clement   pushed down into bcel module
+ * ******************************************************************/
+
+
+package org.aspectj.apache.bcel.generic;
+
+/** we don't actually target instructions, but instructions target us. */
+public class LineNumberTag extends Tag {
+
+    private final int lineNumber;
+
+    public LineNumberTag(int lineNumber) {
+        this.lineNumber = lineNumber;
+    }
+      
+    public int getLineNumber() { return lineNumber; }
+    
+    // ---- from Object
+
+    public String toString() {
+        return "line " + lineNumber;
+    }  
+    public boolean equals(Object other) {
+        if (! (other instanceof LineNumberTag)) return false;
+        return lineNumber == ((LineNumberTag)other).lineNumber;
+    }
+    public int hashCode() {
+        return lineNumber;
+    }
+}
diff --git a/bcel-builder/src/org/aspectj/apache/bcel/generic/LocalVariableTag.java b/bcel-builder/src/org/aspectj/apache/bcel/generic/LocalVariableTag.java
new file mode 100644
index 000000000..53d43c462
--- /dev/null
+++ b/bcel-builder/src/org/aspectj/apache/bcel/generic/LocalVariableTag.java
@@ -0,0 +1,79 @@
+/* *******************************************************************
+ * Copyright (c) 2002 Contributors
+ * All rights reserved. 
+ * This program and the accompanying materials are made available 
+ * under the terms of the Common Public License v1.0 
+ * which accompanies this distribution and is available at 
+ * http://www.eclipse.org/legal/cpl-v10.html 
+ *  
+ * Contributors: 
+ *     PARC     initial implementation 
+ *   Andy Clement   pushed down into bcel module
+ * ******************************************************************/
+
+
+package org.aspectj.apache.bcel.generic;
+
+public final class LocalVariableTag extends Tag {
+	private Type type; // not always known, in which case signature has to be used
+    private final String signature;
+    private final String name;
+    private int slot;
+    private final int startPos;
+    boolean remapped = false;
+
+    // AMC - pr101047, two local vars with the same name can share the same slot, but must in that case
+    // have different start positions.
+    public LocalVariableTag(String sig, String name, int slot, int startPosition) {
+        this.signature = sig;
+        this.name = name;
+        this.slot = slot;
+        this.startPos = startPosition;
+    }
+    
+    public LocalVariableTag(Type t,String sig, String name, int slot, int startPosition) {
+    	this.type = t;
+        this.signature = sig;
+        this.name = name;
+        this.slot = slot;
+        this.startPos = startPosition;
+    }
+
+
+    public String getName()   {return name;}
+    public int getSlot()      {return slot;}
+    public String getType()   {return signature;}
+    public Type getRealType() {return type;}
+    
+    public void updateSlot(int newSlot) {
+    	this.slot = newSlot;
+    	this.remapped = true;
+    }
+    
+    public boolean isRemapped() { return this.remapped; }
+    
+    // ---- from Object
+    
+    public String toString() {
+        return "local " + slot + ": " + signature + " " + name;
+    }
+
+    public boolean equals(Object other) {
+        if (!(other instanceof LocalVariableTag)) return false;
+        LocalVariableTag o = (LocalVariableTag)other;
+        return o.slot == slot && o.startPos == startPos && o.signature.equals(signature) && o.name.equals(name); 
+    }
+    
+    private int hashCode = 0;
+    public int hashCode() {
+        if (hashCode == 0) {
+            int ret = 17;
+            ret = 37*ret + signature.hashCode();
+            ret = 37*ret + name.hashCode();
+            ret = 37*ret + slot;
+            ret = 37*ret + startPos;
+            hashCode = ret;
+        }
+        return hashCode;
+    }
+}
diff --git a/bcel-builder/src/org/aspectj/apache/bcel/generic/MethodGen.java b/bcel-builder/src/org/aspectj/apache/bcel/generic/MethodGen.java
index 96b2b0f90..e414b94e7 100644
--- a/bcel-builder/src/org/aspectj/apache/bcel/generic/MethodGen.java
+++ b/bcel-builder/src/org/aspectj/apache/bcel/generic/MethodGen.java
@@ -86,7 +86,7 @@ import org.aspectj.apache.bcel.generic.annotation.AnnotationGen;
  * use the `removeNOPs' method to get rid off them.
  * The resulting method object can be obtained via the `getMethod()' method.
  *
- * @version $Id: MethodGen.java,v 1.6 2006/02/14 13:32:07 aclement Exp $
+ * @version $Id: MethodGen.java,v 1.7 2006/02/21 10:49:15 aclement Exp $
  * @author  <A HREF="mailto:markus.dahm@berlin.de">M. Dahm</A>
  * @author  <A HREF="http://www.vmeng.com/beard">Patrick C. Beard</A> [setMaxStack()]
  * @see     InstructionList
@@ -100,6 +100,7 @@ public class MethodGen extends FieldGenOrMethodGen {
   private int             max_stack;
   private InstructionList il;
   private boolean         strip_attributes;
+  private int highestLineNumber = 0;
 
   private ArrayList       variable_vec    = new ArrayList();
   private ArrayList       line_number_vec = new ArrayList();
@@ -188,6 +189,8 @@ public class MethodGen extends FieldGenOrMethodGen {
       }
     }
   }
+  
+  public int getHighestlinenumber() { return highestLineNumber; }
 
   /**
    * Instantiate from existing method.
@@ -198,6 +201,10 @@ public class MethodGen extends FieldGenOrMethodGen {
    */
   
   public MethodGen(Method m, String class_name, ConstantPoolGen cp) {
+	  this(m,class_name,cp,false);
+  }
+  
+  public MethodGen(Method m, String class_name, ConstantPoolGen cp,boolean useTags) {
 	  
     this(
     		m.getAccessFlags(), 
@@ -261,29 +268,63 @@ public class MethodGen extends FieldGenOrMethodGen {
 
 				if (a instanceof LineNumberTable) {
 					LineNumber[] ln = ((LineNumberTable) a).getLineNumberTable();
-
-					for (int k = 0; k < ln.length; k++) {
-						LineNumber l = ln[k];
-						addLineNumber(il.findHandle(l.getStartPC(),arrayOfInstructions),
-								l.getLineNumber());
+					if (useTags) {
+						// abracadabra, lets create tags rather than linenumbergens.
+						for (int k = 0; k < ln.length; k++) {
+							LineNumber l = ln[k];
+							int lnum = l.getLineNumber();
+							if (lnum>highestLineNumber) highestLineNumber=lnum;
+							LineNumberTag lt = new LineNumberTag(lnum);
+							il.findHandle(l.getStartPC(),arrayOfInstructions).addTargeter(lt);
+						}
+					} else {
+						for (int k = 0; k < ln.length; k++) {
+							LineNumber l = ln[k];
+							addLineNumber(il.findHandle(l.getStartPC(),arrayOfInstructions),
+									l.getLineNumber());
+						}
 					}
 				} else if (a instanceof LocalVariableTable) {
-					LocalVariable[] lv = ((LocalVariableTable) a).getLocalVariableTable();
-
-					removeLocalVariables();
-
-					for (int k = 0; k < lv.length; k++) {
-						LocalVariable l = lv[k];
-						InstructionHandle start = il.findHandle(l.getStartPC(), arrayOfInstructions);
-						InstructionHandle end   = il.findHandle(l.getStartPC() + l.getLength(), arrayOfInstructions);
-						// AMC, this actually gives us the first instruction AFTER the range,
-						// so move back one... (findHandle can't cope with mid-instruction indices)
-						if (end != null) end = end.getPrev();
-						// Repair malformed handles
-						if (null == start) start = il.getStart();
-						if (null == end)   end = il.getEnd();
-
-						addLocalVariable(l.getName(), Type.getType(l.getSignature()), l.getIndex(), start, end);
+					
+					// Lets have a go at creating Tags directly
+					if (useTags) {
+						LocalVariable[] lv = ((LocalVariableTable) a).getLocalVariableTable();
+						
+						for (int k = 0; k < lv.length; k++) {
+							LocalVariable l = lv[k];
+							Type t = Type.getType(l.getSignature());
+							LocalVariableTag lvt = new LocalVariableTag(t,l.getSignature(),l.getName(),l.getIndex(),l.getStartPC());
+							InstructionHandle start = il.findHandle(l.getStartPC(), arrayOfInstructions);
+							byte b = t.getType();
+							if (b!= Constants.T_ADDRESS) {
+								int increment = t.getSize();
+								if (l.getIndex()+increment>max_locals) max_locals = l.getIndex()+increment;
+							}
+							int end = l.getStartPC()+l.getLength();
+							do {
+								start.addTargeter(lvt);
+								start = start.getNext();
+							} while (start!=null && start.getPosition()<end);
+						}
+					} else {
+					
+						LocalVariable[] lv = ((LocalVariableTable) a).getLocalVariableTable();
+
+						removeLocalVariables();
+	
+						for (int k = 0; k < lv.length; k++) {
+							LocalVariable l = lv[k];
+							InstructionHandle start = il.findHandle(l.getStartPC(), arrayOfInstructions);
+							InstructionHandle end   = il.findHandle(l.getStartPC() + l.getLength(), arrayOfInstructions);
+							// AMC, this actually gives us the first instruction AFTER the range,
+							// so move back one... (findHandle can't cope with mid-instruction indices)
+							if (end != null) end = end.getPrev();
+							// Repair malformed handles
+							if (null == start) start = il.getStart();
+							if (null == end)   end = il.getEnd();
+	
+							addLocalVariable(l.getName(), Type.getType(l.getSignature()), l.getIndex(), start, end);
+						}
 					}
 				} else addCodeAttribute(a);
 			}
diff --git a/bcel-builder/src/org/aspectj/apache/bcel/generic/Tag.java b/bcel-builder/src/org/aspectj/apache/bcel/generic/Tag.java
new file mode 100644
index 000000000..2cb5f9ddc
--- /dev/null
+++ b/bcel-builder/src/org/aspectj/apache/bcel/generic/Tag.java
@@ -0,0 +1,42 @@
+/* *******************************************************************
+ * Copyright (c) 2002 Contributors
+ * All rights reserved. 
+ * This program and the accompanying materials are made available 
+ * under the terms of the Common Public License v1.0 
+ * which accompanies this distribution and is available at 
+ * http://www.eclipse.org/legal/cpl-v10.html 
+ *  
+ * Contributors: 
+ *     PARC     initial implementation 
+ *   Andy Clement   pushed down into bcel module
+ * ******************************************************************/
+
+
+package org.aspectj.apache.bcel.generic;
+
+
+/** A tag is an instruction-targeter that doesn't bother remembering its target(s) */
+public abstract class Tag implements InstructionTargeter, Cloneable {
+
+    public Tag() {
+    }
+
+    // ---- from InstructionTargeter
+    public boolean containsTarget(InstructionHandle ih) {
+        return false;
+    }
+
+    public void updateTarget(InstructionHandle old_ih, InstructionHandle new_ih) {
+        old_ih.removeTargeter(this);
+        if (new_ih != null)
+            new_ih.addTargeter(this);
+    }
+    
+    public Tag copy() {
+    	try {
+    		return (Tag)clone();
+    	} catch (CloneNotSupportedException e) {
+    		throw new RuntimeException("Sanity check, can't clone me");
+    	}
+    }
+}