(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
http://cr.openjdk.java.net/~cfang/6837146/webrev.00/
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
unswitched.
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.
Thanks,
Changpeng
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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