tree a2414f873e0d118b79784aa562e4dfa2e99f3350
parent 0307427c8dc0994cbe40b3a2b717830a6484cbb9
author Jesse Wilson <jessewilson@apache.org> 1260435389 +0000
committer Jesse Wilson <jessewilson@apache.org> 1260435389 +0000

Changing AbstractList's iterator to track elements remaining rather than elements already returned.

On DRLVM, this results in a modest 10% runtime improvement in iteration. When I used -Xbootclasspath to run the current and new code on hotspot, the improvement was more pronounced. Runtimes are below; the benchmark results are below.
http://code.google.com/p/caliper/source/browse/trunk/test/com/google/caliper/examples/ListIterationBenchmarkSuite.java?spec=svn17&r=17

length       vm    ns logarithmic runtime
     0       RI    20 |||||||||||
     0  current    16 ||||||||||
     0      new    14 ||||||||||
    10       RI    63 ||||||||||||||||
    10  current    82 |||||||||||||||||
    10      new    45 ||||||||||||||
   100       RI   393 |||||||||||||||||||||||
   100  current   672 |||||||||||||||||||||||||
   100      new   243 |||||||||||||||||||||
  1000       RI  1191 |||||||||||||||||||||||||||
  1000  current  2153 ||||||||||||||||||||||||||||||
  1000      new  1294 ||||||||||||||||||||||||||||


git-svn-id: https://svn.apache.org/repos/asf/harmony/enhanced/classlib/trunk@889145 13f79535-47bb-0310-9956-ffa450edef68