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Bug ID: JDK-6488063 Improve analysis by Bytecode Escape Estimator
JDK-6488063 : Improve analysis by Bytecode Escape Estimator

Details
Type:
Bug
Submit Date:
2006-10-31
Status:
Resolved
Updated Date:
2010-05-20
Project Name:
JDK
Resolved Date:
2006-12-15
Component:
hotspot
OS:
generic
Sub-Component:
compiler
CPU:
generic
Priority:
P3
Resolution:
Fixed
Affected Versions:
7
Fixed Versions:
hs10 (b05)

Related Reports
Backport:
Backport:

Sub Tasks

Description
Currently, the Bytecode Escape Estimator used by escape analysis does
a very conservative analysis.  In particular, it does not track values on the
execution stack across block boundaries or arguments stored to another local
variable.  The analysis should be improved to perform this tracking.

                                    

Comments
EVALUATION

I have improved the Bytecode Escape Estimator to do this tracking.  I have
also added improved tracking of whether a method returns a newly allocated
unescaped object.

As part of this work, I needed to improve the block analysis.  There are now
3 places where this analysis is done.  I have extracted this into a new
class ciMethodBlocks which allows the analysis to be shared by all 3 places.
                                     
2006-10-31



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