RFR: 8162865 Implementation of SPARC lzcnt

Trevor Watson trevor.d.watson at oracle.com
Tue Nov 15 11:57:50 UTC 2016


I have implemented the code to use the lzcnt instruction for both 
integer and long countLeadingZeros() methods on SPARC platforms 
supporting the vis3 instruction set.

Current "bmi" tests for the above are updated so that they run on both 
SPARC and x86 platforms.

I've also implemented a test to ensure that Integer.countLeadingZeros() 
and Long.countLeadingZeros() return the correct values when C2 runs. 
This test is currently under the intrinsics "bmi" tests for want of 
somewhere better (they do apply to both SPARC and x86 though).

http://cr.openjdk.java.net/~alanbur/8162865/

Thanks,
Trevor


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