Hi,
the attached patch moves exception handling code out of the common case
for elementAt of both java.util.Vector and java.util.elementAt, this
helps JIT compilation inline the common non-exception throwing case (and
avoid expense incurred by considering StringBuilders, etc.). Other than
fixing coding convention issues, are there any objections to this change?
Thanks,
Ian
--
http://www.cs.man.ac.uk/~irogers/
Index: java/util/ArrayList.java
===================================================================
RCS file: /sources/classpath/classpath/java/util/ArrayList.java,v
retrieving revision 1.31
diff -u -r1.31 ArrayList.java
--- java/util/ArrayList.java 10 Dec 2006 20:25:46 -0000 1.31
+++ java/util/ArrayList.java 23 Apr 2008 14:17:43 -0000
@@ -472,8 +472,7 @@
// use of a negative index will cause an ArrayIndexOutOfBoundsException,
// a subclass of the required exception, with no effort on our part.
if (index > size)
- throw new IndexOutOfBoundsException("Index: " + index + ", Size: "
- + size);
+ raiseBoundsError(index);
}
/**
@@ -488,11 +487,23 @@
// use of a negative index will cause an ArrayIndexOutOfBoundsException,
// a subclass of the required exception, with no effort on our part.
if (index >= size)
- throw new IndexOutOfBoundsException("Index: " + index + ", Size: "
- + size);
+ raiseBoundsError(index);
}
/**
+ * Raise the ArrayIndexOfOutBoundsException.
+ * @param index the index of the access
+ * @throws IndexOutOfBoundsException unconditionally
+ */
+ private void raiseBoundsError(int index)
+ {
+ // Implementaion note: put in a separate method to make the JITs job
easier
+ // (separate common from uncommon code at method boundaries when
trivial to do so).
+ throw new IndexOutOfBoundsException("Index: " + index + ", Size: " +
size);
+ }
+
+
+ /**
* Remove from this list all elements contained in the given collection.
* This is not public, due to Sun's API, but this performs in linear
* time while the default behavior of AbstractList would be quadratic.
Index: java/util/Vector.java
===================================================================
RCS file: /sources/classpath/classpath/java/util/Vector.java,v
retrieving revision 1.31
diff -u -r1.31 Vector.java
--- java/util/Vector.java 12 Mar 2008 23:39:51 -0000 1.31
+++ java/util/Vector.java 23 Apr 2008 14:17:43 -0000
@@ -909,7 +909,7 @@
// use of a negative index will cause an ArrayIndexOutOfBoundsException
// with no effort on our part.
if (index > elementCount)
- throw new ArrayIndexOutOfBoundsException(index + " > " + elementCount);
+ raiseBoundsError(index, " > ");
}
/**
@@ -924,10 +924,23 @@
// use of a negative index will cause an ArrayIndexOutOfBoundsException
// with no effort on our part.
if (index >= elementCount)
- throw new ArrayIndexOutOfBoundsException(index + " >= " + elementCount);
+ raiseBoundsError(index, " >= ");
}
/**
+ * Raise the ArrayIndexOfOutBoundsException.
+ * @param index the index of the access
+ * @param operator the operator to include in the error message
+ * @throws IndexOutOfBoundsException unconditionally
+ */
+ private void raiseBoundsError(int index, String operator)
+ {
+ // Implementaion note: put in a separate method to make the JITs job
easier
+ // (separate common from uncommon code at method boundaries when
trivial to do so).
+ throw new ArrayIndexOutOfBoundsException(index + operator +
elementCount);
+ }
+
+ /**
* Serializes this object to the given stream.
*
* @param s the stream to write to
