(Resend with description) Re: Request for review (XS): 6837146 Should perform unswitch before maximally unroll in loop transformation

Changpeng Fang Changpeng.Fang at Sun.COM
Mon May 4 15:49:10 PDT 2009


Problem Summary:
The concern is the ordering of maximally unroll and unswitch of a loop 
in loop transformation.
Current implementation is that maximally unroll is performed before loop 
unswitch. The problem
is if a loop is maximally unrolled (fully unrolled), it will never be 
unswitched. This will leave
many conditional statements (blocks) in the code which should not appear 
if the loop can be

Proposed Solution:
Change the ordering of unswitch and maximally_unroll in loop 
transformation. After unswitch,
the loop should still be able to be maximally unrolled.



On 05/04/09 15:05, Changpeng Fang wrote:
> http://cr.openjdk.java.net/~cfang/6837146/webrev.00/
> Summary: Change the ordering of do_unswitch and do_maximally_unroll in 
> loop transformation.
> Thanks,
> Changpeng

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