RFR 8080325 SuperWord loop unrolling analysis

[Vladimir Kozlov]

Good.

Michael, please, update changes to latest hs-comp/hotspot sources:

applying hotspot_8080325.patch
patching file src/share/vm/opto/loopTransform.cpp
Hunk #6 FAILED at 1632
1 out of 7 hunks FAILED -- saving rejects to file 
src/share/vm/opto/loopTransform.cpp.rej

Thanks,
Vladimir

On 6/15/15 11:37 PM, Berg, Michael C wrote:
> Roland, thanks for the review.
> You will find the latest changes in the following webrev:
>
> http://cr.openjdk.java.net/~mcberg/8080325/webrev.02/
>
> All comments below are addressed within the changes.
>
> Regards,
> Michael
>
> -----Original Message-----
> From: Roland Westrelin [mailto:roland.westrelin at oracle.com]
> Sent: Tuesday, June 09, 2015 6:02 AM
> To: Berg, Michael C
> Cc: HotSpot Compiler
> Subject: Re: RFR 8080325 SuperWord loop unrolling analysis
>
>> http://cr.openjdk.java.net/~mcberg/8080325/webrev.01/
>
> Since you’re touching that code, can you also fix the coding style in:
>
> In loopTransform.cpp
>
> 644 bool IdealLoopTree::policy_unroll( PhaseIdealLoop *phase ) {
>
> In loopnode.hpp
>
> 462   bool policy_unroll( PhaseIdealLoop *phase );
>
> (no spaces after/before the parenthesis)
>
> In loopnode.hpp:
>
> 164   int slp_maximum_unroll_factor;
>
> should be: _slp_maximum_unroll_factor
>
> 248   int  slp_max_unroll()                      { return slp_maximum_unroll_factor; }
>
> could be: int  slp_max_unroll() const {
>
>   464   // Return TRUE or FALSE if the loop analyzes to map to a maximal
>   465   // superword unrolling for vectorization.
>   466   void policy_unroll_slp_analysis(CountedLoopNode *cl, PhaseIdealLoop *phase, int future_unroll_ct);
>
> The comment says the function returns something but it doesn’t return anything.
>
> I don’t see slp_maximum_unroll_factor being initialized to a default value. Isn’t there a risk it’s not set when we read it?
>
> Otherwise, I think it’s good.
>
> Roland.
>