United StatesChange Country, Oracle Worldwide Web Sites Communities I am a... I want to...
Bug ID: JDK-6339956 Eliminate locking of unescaped objects
JDK-6339956 : Eliminate locking of unescaped objects

Details
Type:
Bug
Submit Date:
2005-10-21
Status:
Resolved
Updated Date:
2010-04-02
Project Name:
JDK
Resolved Date:
2005-12-07
Component:
hotspot
OS:
generic
Sub-Component:
compiler
CPU:
generic
Priority:
P3
Resolution:
Fixed
Affected Versions:
6
Fixed Versions:

Related Reports
Relates:

Sub Tasks

Description
Escape analysis was recently added to Compiler2.  However there are currently no
optimizations which take advantage of it.  Adding an optimization to eliminate
locking and unlocking of unescaped objects is an easy, safe optimization to
take advantage of escape analysis.

                                    

Comments
EVALUATION

Eliminating locking on unescaped objects has been added.  As part of this change,
the bytecode escape estimator was added.  Without it, almost no opportunities for
this optimization are detected.

This optimization is only effective when the DoEscapeAnalysis flag is turned on
(it is off by default.)
                                     
2005-12-01
SUGGESTED FIX

PRT webrev:

http://analemma.sfbay.sun.com/net/prt-archiver.sfbay/data/archived_workspaces/main/c2_baseline/2005/20051130105101.steved.escape_analysis_ws/workspace/webrevs/webrev-2005.11.30/index.html
                                     
2005-12-02



Hardware and Software, Engineered to Work Together