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Bug ID: JDK-8003848 Make ConstMethod::generic_signature_index optional and move Method::_max_stack to ConstMethod
JDK-8003848 : Make ConstMethod::generic_signature_index optional and move Method::_max_stack to ConstMethod

Details
Type:
Enhancement
Submit Date:
2012-11-21
Status:
Closed
Updated Date:
2014-06-26
Project Name:
JDK
Resolved Date:
2012-11-28
Component:
hotspot
OS:
generic
Sub-Component:
runtime
CPU:
generic
Priority:
P3
Resolution:
Fixed
Affected Versions:
Fixed Versions:
hs25 (b11)

Related Reports
Backport:

Sub Tasks

Description
Majority of java methods do not have generic signature. For those methods, ConstMethod::generic_signature_index is always 0. ConstMethod::generic_signature_index can be optional and only allocated for methods with generic signature.

The Method class has a 2-byte unused space due to padding. Method::_max_stack can be moved to ConstMethod after changing ConstMethod::generic_signature_index to be optionally allocated. This removes an u2 field in Method, and can avoid wasting 2-byte unused space due to padding.

Together, above would save 4-bytes for method without generic signature.
                                    

Comments
URL:   http://hg.openjdk.java.net/hsx/hotspot-emb/hotspot/rev/b2dbd323c668
User:  jiangli
Date:  2012-11-28 01:44:54 +0000

                                     
2012-11-28



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