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Bug ID: JDK-7132690 InstanceKlass::_reference_type should be u1 type
JDK-7132690 : InstanceKlass::_reference_type should be u1 type

Details
Type:
Enhancement
Submit Date:
2012-01-24
Status:
Closed
Updated Date:
2012-10-13
Project Name:
JDK
Resolved Date:
2012-02-11
Component:
hotspot
OS:
generic
Sub-Component:
runtime
CPU:
generic
Priority:
P4
Resolution:
Fixed
Affected Versions:
8
Fixed Versions:
hs23 (b15)

Related Reports
Backport:
Backport:

Sub Tasks

Description
The ReferenceType is defined as an enum with 6 values (src/share/vm/utilities/globalDefinitions.hpp). The InstanceKlass::_reference_type is an int type. It can be reduced to u1 type. Move the field within InstanceKlass to utilize unused memory can save 4-byte for each class.

                                    

Comments
EVALUATION

The suggestion in Description section will be implemented.
                                     
2012-01-24
EVALUATION

http://hg.openjdk.java.net/hsx/hotspot-emb/hotspot/rev/a79cb7c55012
                                     
2012-01-26
EVALUATION

http://hg.openjdk.java.net/hsx/hotspot-comp/hotspot/rev/a79cb7c55012
                                     
2012-02-18
EVALUATION

http://hg.openjdk.java.net/hsx/hotspot-gc/hotspot/rev/a79cb7c55012
                                     
2012-02-18
EVALUATION

http://hg.openjdk.java.net/lambda/lambda/hotspot/rev/a79cb7c55012
                                     
2012-03-22



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