JDK-8038297 : Avoid placing CTI immediately following cbcond instruction on T4
Type:Bug
Component:hotspot
Sub-Component:compiler
Affected Version:hs22
Priority:P3
Status:Resolved
Resolution:Fixed
OS:generic
CPU:sparc
Submitted:2014-03-25
Updated:2019-09-13
Resolved:2014-04-11
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Code generated for T4 and related SPARC processors should avoid placing Control Transfer Instructions [CTI] such as call and retl immediately following a cbcond instruction.
Comments
I asked Igor to look on this. He recently worked on an other cbcond problem: 8035283.
26-03-2014
Looks like it is reasonable request. Richard, can you attach your microbenchmark to the bug report so we can measure the same performance difference?
25-03-2014
Is it the problem only on T4? Or also on all newer T-SPARC?
25-03-2014
Richard, can you point any documents about this? There was only restriction on placing an other cbcond instruction after first.