[OpenJDK 2D-Dev] <AWT Dev> RFR(XS): 8160721: Avoid deoptimizations in Font.equals.

[Volker Simonis]

Hi Goetz,

it would be really interesting to see the use case where this has been
a performance issue.

But even without that I agree with your comments in the bug. Phil's
fear that you introduce an extra 'instanceof' check for the positive
case is unfounded. I've attached a small example program to the bug
which shows that the common case is the same for both version, only
the uncommon version where the paramter is not a Font object is
slightly more complicated in the original version because of the extra
exception handling code.

So in general the change looks good!
Please push it to the client repo.

Regards,
Volker


On Thu, Jul 7, 2016 at 9:04 AM, Lindenmaier, Goetz
<goetz.lindenmaier at sap.com> wrote:
> Hi,
>
> can I consider this reviewed?
> Remi Forax and Phil Race had a look at this.
>
> Best regards,
>  Goetz.
>
>> -----Original Message-----
>> From: Lindenmaier, Goetz
>> Sent: Montag, 4. Juli 2016 08:33
>> To: 'Phil Race' <philip.race at oracle.com>; awt-dev at openjdk.java.net; 2d-dev
>> <2d-dev at openjdk.java.net>
>> Subject: RE: <AWT Dev> RFR(XS): 8160721: Avoid deoptimizations in
>> Font.equals.
>>
>> Hi,
>>
>> Resending this to 2d-dev.
>>
>> Also, I made a new webrev considering Remi's comments:
>> http://cr.openjdk.java.net/~goetz/wr16/8160721-deoptFont/webrev.02/
>>
>> Best regards,
>>   Goetz.
>>
>>
>> > -----Original Message-----
>> > From: Phil Race [mailto:philip.race at oracle.com]
>> > Sent: Freitag, 1. Juli 2016 19:35
>> > To: Lindenmaier, Goetz <goetz.lindenmaier at sap.com>; awt-
>> > dev at openjdk.java.net
>> > Subject: Re: <AWT Dev> RFR(XS): 8160721: Avoid deoptimizations in
>> > Font.equals.
>> >
>> > Please resend this to 2d-dev. All font related API and implementation
>> > is part of 2D, not AWT.
>> >
>> > -phil.
>> >
>> > On 7/1/2016 6:59 AM, Lindenmaier, Goetz wrote:
>> > >
>> > > Hi,
>> > >
>> > > This small fix improves performance of the C2 compiler.
>> > >
>> > > We see deoptimizations due to class casts in Font.equals.
>> > > Use instanceof check instead of catching the exception.
>> > >
>> > > Please review this change:
>> > >
>> > > http://cr.openjdk.java.net/~goetz/wr16/8160721-deoptFont/
>> > > <http://cr.openjdk.java.net/%7Egoetz/wr16/8160721-deoptFont/>
>> > >
>> > > Best regards,
>> > >
>> > >   Goetz.
>> > >
>