RFR: 8213754: PPC64: Add Intrinsics for isDigit/isLowerCase/isUpperCase/isWhitespace
Michihiro Horie
HORIE at jp.ibm.com
Fri Dec 7 08:13:41 UTC 2018
Hi Roger,
I updated my webrev.
http://cr.openjdk.java.net/~mhorie/8213754/webrev.04/
>0x80 might be a good choice or 0xff.
I agree, thanks.
>I was wondering about the performance without the PPC specific intrinsic
but with the
>CharacterDataLatin1.java.template code for isDigit being:
> return '0' <= ch && ch <= '9';
I now understand your point, thanks for your explanation. Both on Power9
and Skylake, the isDigit(ch) using ‘0’…’9’ explicitly in
CharacterDataLatin1.java.template without PPC specific intrinsic was around
15% faster than the original code that does not include my changes. I fixed
my change using ‘0’…’9’ for this isDigit(ch).
Best regards,
--
Michihiro,
IBM Research - Tokyo
From: Roger Riggs <Roger.Riggs at oracle.com>
To: Michihiro Horie <HORIE at jp.ibm.com>
Cc: core-libs-dev at openjdk.java.net,
hotspot-compiler-dev at openjdk.java.net, martin.doerr at sap.com,
vladimir.kozlov at oracle.com, volker.simonis at sap.com
Date: 2018/12/07 01:23
Subject: Re: RFR: 8213754: PPC64: Add Intrinsics for
isDigit/isLowerCase/isUpperCase/isWhitespace
Hi Michihiro,
On 12/06/2018 02:38 AM, Michihiro Horie wrote:
Hi Roger,
Thank you for your helpful comments. I updated new webrev, adding a
parameter in the jmh test to measure ‘other’ characters and moving
the file to an appropriate location, also fixing the indents and
copyright year.
http://cr.openjdk.java.net/~mhorie/8213754/webrev.03/
The choice of 256 for other is outside the range of Latin1 which is 0..255.
0x80 might be a good choice or 0xff.
>Is there an opportunity to improve the performance of isDigit using
explicit '0'.. '9'
>in CharacterDataLatin1.java.template? The performance would need to
be measured and compared.
Yes, there is an opportunity: intrinsic performed 25% better than the
original on Power9.
I was wondering about the performance without the PPC specific intrinsic
but with the
CharacterDataLatin1.java.template code for isDigit being:
return '0' <= ch && ch <= '9';
>Is the profile of in-lining methods changed in any measurable way
now that
>there is an extra level of method invocation?
> Character.isLowerCase(ch) -> CharacterData.isLowerCase(ch) ->
getType(ch) == LOWERCASE_LETTER;
>
>instead of:
> Character.isLowerCase(ch) -> getType(ch) == LOWERCASE_LETTER;
I missed this point, thanks. I tried jstack but could not find
additional level.
LogCompilation shows CharacterDataLatin1.isLowerCase(ch) is compiled
in c1:
<nmethod compile_id='71' compiler='c1' level='3'
entry='0x00003fff5911cd00' size='1472' address='0x00003fff5911cb90'
relocation_offset='344' insts_offset='368' stub_offset='1136'
scopes_data_offset='1248' scopes_pcs_offset='1336'
dependencies_offset='1448' nul_chk_table_offset='1456'
oops_offset='1184' metadata_offset='1192'
method='java.lang.CharacterDataLatin1 isLowerCase (I)Z' bytes='15'
count='1024' iicount='1025' stamp='0.058'/>
Supposing some existing complex code was already taking advantage of the
full allowed inline depth.
Then adding an extra level might change the inlining behavior.
Existing methods in CharacterDataLatin1.java.template etc. directly
invoke getProperties(ch), so isLowerCase(ch) would be more aligned
with other methods if it looks like as follows?
+ @HotSpotIntrinsicCandidate
+ boolean isLowerCase(int ch) {
+ int props = getProperties(ch);
+ return (props & $$maskType) == Character.LOWERCASE_LETTER;
+ }
Yes, that would alleviate my concern.
Thanks, Roger
Best regards,
--
Michihiro,
IBM Research - Tokyo
Inactive
hide details for Roger Riggs ---2018/12/06
05:09:36---Hi
Michihiro, On 12/05/2018 07:21 AM, Michihiro
Horie wrote:Roger Riggs ---2018/12/06 05:09:36---Hi Michihiro, On
12/05/2018 07:21 AM, Michihiro Horie wrote:
From: Roger Riggs <Roger.Riggs at oracle.com>
To: Michihiro Horie <HORIE at jp.ibm.com>, vladimir.kozlov at oracle.com
Cc: core-libs-dev at openjdk.java.net,
hotspot-compiler-dev at openjdk.java.net, martin.doerr at sap.com,
volker.simonis at sap.com
Date: 2018/12/06 05:09
Subject: Re: RFR: 8213754: PPC64: Add Intrinsics for
isDigit/isLowerCase/isUpperCase/isWhitespace
Hi Michihiro,
On 12/05/2018 07:21 AM, Michihiro Horie wrote:
>There are a few JMH tests for upper and lower in the
jmh-jdk-microbenchmarks repo. [1]
Here is a jmh webrev for the Character methods.
http://cr.openjdk.java.net/~mhorie/8213754/jmh-webrev.00/
Please include at least one character value that is not a member of
any of the classes.
The performance impact for 'other' characters is important also.
The JMH tests have been moved to the OpenJDK jdk/jdk repo in the
directory:
test/micro/org/openjdk/bench/java/lang/
Now that they are in that repo, they can be included with the rest of
the changeset.
Also, I updated C2 changes in the latest webrev. (Thank
you for giving valuable comments off-list, Vladimir and
Martin!)
With the change in is_disabled_by_flags, I added a JVM
flag that will need another review request. I would
proceed for it if this RFR is accepted.
http://cr.openjdk.java.net/~mhorie/8213754/webrev.02/
The indent in the Java code should be 4 spaces. (Native lib code is 4
spaces, Hotspot is 2 spaces)
Please update the copyrights to include 2018.
Is there an opportunity to improve the performance of isDigit using
explicit '0'.. '9'
in CharacterDataLatin1.java.template? The performance would need to
be measured and compared.
Is the profile of in-lining methods changed in any measurable way now
that
there is an extra level of method invocation?
Character.isLowerCase(ch) -> CharacterData.isLowerCase(ch) ->
getType(ch) == LOWERCASE_LETTER;
instead of:
Character.isLowerCase(ch) -> getType(ch) == LOWERCASE_LETTER;
Regards, Roger
I need a review on changes in the class library, anyway.
Would be grateful if I could have one.
Best regards,
--
Michihiro,
IBM Research - Tokyo
----- Original message -----
From: Michihiro Horie/Japan/IBM
To: Vladimir Kozlov <vladimir.kozlov at oracle.com>
Cc: core-libs-dev <core-libs-dev at openjdk.java.net>,
hotspot-compiler-dev at openjdk.java.net,
martin.doerr at sap.com, Roger Riggs
<roger.riggs at oracle.com>, volker.simonis at sap.com
Subject: Re: RFR: 8213754: PPC64: Add Intrinsics for
isDigit/isLowerCase/isUpperCase/isWhitespace
Date: Fri, Nov 30, 2018 1:01 PM
Hi Vladimir,
Thank you for your further comments. I fixed my code, but
I’m afraid discussing such a basic topic involving the
two big mailing lists is not good. Please let me have a
chance to talk on this off-list.
Best regards,
--
Michihiro,
IBM Research - Tokyo
Vladimir Kozlov ---2018/11/30 03:01:42---Hi Michihiro, I
still do not understand which Region node you are
swapping. Where it is coming from?
From: Vladimir Kozlov <vladimir.kozlov at oracle.com>
To: Michihiro Horie <HORIE at jp.ibm.com>, Roger Riggs
<roger.riggs at oracle.com>
Cc: core-libs-dev <core-libs-dev at openjdk.java.net>,
hotspot-compiler-dev at openjdk.java.net,
martin.doerr at sap.com, volker.simonis at sap.com
Date: 2018/11/30 03:01
Subject: Re: RFR: 8213754: PPC64: Add Intrinsics for
isDigit/isLowerCase/isUpperCase/isWhitespace
Hi Michihiro,
I still do not understand which Region node you are
swapping. Where it is coming from?
> + // Swap current RegionNode with new one
Regards,
Vladimir
On 11/28/18 10:31 PM, Michihiro Horie wrote:
> Vladimir,Roger,
> Thank you so much for your responses.
>
> Vladimir,
> Regarding the hotspot change,I’m new in changing around
library_call.cpp,so your comments are very helpful. I
will fix
> my code,especially inline_character_compare()would be
like:
>
> +bool LibraryCallKit::inline_character_compare
(vmIntrinsics::ID id){
> + RegionNode* old_rgn = control()->as_Region();
> + RegionNode* new_rgn = new RegionNode(1);
> + record_for_igvn(new_rgn);
> +
> + // Swap current RegionNode with new one
> + Node* new_ctrl = old_rgn->in(1);
> + old_rgn->del_req(1);
> + new_rgn->add_req(new_ctrl);
> +
> + set_control(_gvn.transform(new_rgn));
> +
> + // argument(0)is receiver
> + Node* codePoint = argument(1);
> + Node* n = NULL;
> +
> + switch (id){
> + case vmIntrinsics::_isDigit_c : n = new DigitCNode
(control(),codePoint);break;
> + case vmIntrinsics::_isLowerCase_c : n = new
LowerCaseCNode(control(),codePoint);break;
> + case vmIntrinsics::_isUpperCase_c : n = new
UpperCaseCNode(control(),codePoint);break;
> + case vmIntrinsics::_isWhitespace_c : n = new
WhitespaceCNode(control(),codePoint);break;
> + default:
> + fatal_unexpected_iid(id);
> + }
> +
> + set_result(_gvn.transform(n));
> + return true;
> +}
>
> Microbenchmark showed ~40% improvements.
>
> Roger,
> I would wait foryour review,thanks. I understood the
discussion had not been recognized from people in
core-libs-dev,and
> checked it was not actually archived there….
>
> Best regards,
> --
> Michihiro,
> IBM Research - Tokyo
>
> Inactive hide details for Roger Riggs ---2018/11/29
11:21:26---Hi, I'll look at it on Thursday.Roger Riggs
---2018/11/29
> 11:21:26---Hi, I'll look at it on Thursday.
>
> From: Roger Riggs <roger.riggs at oracle.com>
> To: Vladimir Kozlov <vladimir.kozlov at oracle.com>,
Michihiro Horie <HORIE at jp.ibm.com>,
core-libs-dev at openjdk.java.net
> Cc: volker.simonis at sap.com,
hotspot-compiler-dev at openjdk.java.net,
martin.doerr at sap.com
> Date: 2018/11/29 11:21
> Subject: Re: RFR: 8213754: PPC64: Add Intrinsics for
isDigit/isLowerCase/isUpperCase/isWhitespace
>
>
------------------------------------------------------------------------------------------------------------------------
>
>
>
> Hi,
>
> I'll look at it on Thursday.
>
> In spite of it looking like the email was sent to
core-lib-dev, I have
> not seen it before
> and its not in the core-libs-dev archive.
>
> $.02, Roger
>
> On 11/28/18 7:15 PM, Vladimir Kozlov wrote:
> > You still need review from core-libs.
> >
> > About your hotspot changes. You need to add
intrinsics to
> > is_disabled_by_flags() to be able switch them off.
> >
> > Note, match_rule_supported() calls in
> > C2Compiler::is_intrinsic_supported() executed before
intrinsics in C2
> > are registered. So they will not be available if
they are not
> > supported. match_rule_supported() checks in
> > LibraryCallKit::inline_character_compare() are not
needed.
> >
> > I don't get what you code in
> > LibraryCallKit::inline_character_compare() is doing.
Why you check
> > Region node at the beginning and why you add Region
and Phi at the end
> > if you have only one path?
> > You are creating code for whole method which should
return boolean result
> >
> > + boolean isDigit(int ch) {
> > + return getType(ch) ==
Character.DECIMAL_DIGIT_NUMBER;
> > + }
> >
> > but your code produce TypeInt::CHAR. why?
> >
> > An finally. Did you compare code generated by
default and with you
> > changes? what improvement you see?
> >
> > Thanks,
> > Vladimir
> >
> > On 11/28/18 3:07 PM, Michihiro Horie wrote:
> >> Is there any response from core-libs-dev?
> >>
> >> Vladimir,
> >> Could you give your suggestion on how to proceed?
> >>
> >>
> >> Best regards,
> >> --
> >> Michihiro,
> >> IBM Research - Tokyo
> >>
> >>
> >> ----- Original message -----
> >> From: "Michihiro Horie" <HORIE at jp.ibm.com>
> >> Sent by: "hotspot-compiler-dev"
> >> <hotspot-compiler-dev-bounces at openjdk.java.net>
> >> To: "Doerr, Martin" <martin.doerr at sap.com>
> >> Cc: "Simonis, Volker" <volker.simonis at sap.com>,
> >> "hotspot-compiler-dev at openjdk.java.net"
<hotspot-compiler-dev at openjdk.java.net>,
> >> "core-libs-dev at openjdk.java.net"
<core-libs-dev at openjdk.java.net>
> >> Subject: RE: 8213754: PPC64: Add Intrinsics for
> >> isDigit/isLowerCase/isUpperCase/isWhitespace
> >> Date: Thu, Nov 22, 2018 11:28 AM
> >>
> >> Hi Martin,
> >>
> >> Yes, we should wait for the feedback on class
library change.
> >>
> >> >Btw. I think you can further simplify the code in
library_call.cpp
> >> (no phi). But we can discuss details when
thedirection regarding the
> >> java classes is clear.
> >> Thank you for pointing out it, I think I understand
how to simplify
> >> code.
> >>
> >> >Hi Michi,
> >> >
> >> >On 11/20/2018 02:52 PM, Michihiro Horie wrote:
> >> >> >Please note that we don’t have a machine, yet.
So other people
> >> will have to test.
> >> >> I think Gustavo can help testing this change
when its' ready.
> >> >Sure :)
> >> >
> >> >Best regards,
> >> >Gustavo
> >> Thank you, Gustavo.
> >>
> >>
> >> Best regards,
> >> --
> >> Michihiro,
> >> IBM Research - Tokyo
> >>
> >> Inactive hide details for "Doerr, Martin"
---2018/11/22 01:33:34---Hi
> >> Michihiro, thanks. This proposal makes the javacode
much"Doerr,
> >> Martin" ---2018/11/22 01:33:34---Hi Michihiro,
thanks. This proposal
> >> makes the java code much moreintrinsics friendly.
> >>
> >> From: "Doerr, Martin" <martin.doerr at sap.com>
> >> To: Michihiro Horie <HORIE at jp.ibm.com>,
> >> "core-libs-dev at openjdk.java.net"
<core-libs-dev at openjdk.java.net>
> >> Cc: "hotspot-compiler-dev at openjdk.java.net"
> >> <hotspot-compiler-dev at openjdk.java.net>, "Simonis,
> >> Volker"<volker.simonis at sap.com>, Gustavo Romero
> >> <gromero at linux.vnet.ibm.com>
> >> Date: 2018/11/22 01:33
> >> Subject: RE: 8213754: PPC64: Add Intrinsics for
> >> isDigit/isLowerCase/isUpperCase/isWhitespace
> >>
> >>
>
------------------------------------------------------------------------------------------------------------------------
> >>
> >>
> >>
> >>
> >> Hi Michihiro,
> >>
> >> thanks. This proposal makes the java code much more
intrinsics friendly.
> >> We should wait for feedback from the core lib
folks. Maybe they have
> >> some requirements or other proposals.
> >>
> >> I think these intrinsics should be interesting for
Oracle, Intel and
> >> others, too.
> >>
> >> Btw. I think you can further simplify the code in
library_call.cpp
> >> (no phi). But we can discuss details when
thedirection regarding the
> >> java classes is clear.
> >>
> >> Best regards,
> >> Martin
> >>
> >> *
> >> **From:*Michihiro Horie <HORIE at jp.ibm.com>*
> >> **Sent:*Mittwoch, 21. November 2018 17:14*
> >> **To:*core-libs-dev at openjdk.java.net; Doerr, Martin
> >> <martin.doerr at sap.com>*
> >> **Cc:*hotspot-compiler-dev at openjdk.java.net;
Simonis, Volker
> >> <volker.simonis at sap.com>; Gustavo Romero
<gromero at linux.vnet.ibm.com>*
> >> **Subject:*RE: 8213754: PPC64: Add Intrinsics for
> >> isDigit/isLowerCase/isUpperCase/isWhitespace
> >>
> >> Hi Martin,
> >>
> >> I send this RFR to core-libs-dev too, because it
changes the class
> >> library.
> >>
> >> Through trial and error, I separated Latin1 block
as in the _
> >>
> __http://cr.openjdk.java.net/~mhorie/8213754/webrev.01_
>
> >> <
http://cr.openjdk.java.net/%7Emhorie/8213754/webrev.01
>_/_
> >>
> >> I followed the coding way of Character.isWhitespace
() that invokes
> >> each ChracterData’s isWhitespace() to
refactorisDigit(),
> >> isLowerCase(), and isUpperCase().
> >>
> >> I think this change is also useful on x86, using
STTNI.
> >>
> >>
> >> Best regards,
> >> --
> >> Michihiro,
> >> IBM Research - Tokyo
> >>
> >>
> >> ----- Original message -----
> >> From: "Michihiro Horie" <_HORIE at jp.ibm.com_ <
mailto:HORIE at jp.ibm.com>>
> >> Sent by: "hotspot-compiler-dev"
> >> <_hotspot-compiler-dev-bounces at openjdk.java.net_<
mailto:hotspot-compiler-dev-bounces at openjdk.java.net>>
> >> To: "Doerr, Martin" <_martin.doerr at sap.com_
> >> <mailto:martin.doerr at sap.com>>
> >> Cc: "Simonis, Volker" <_volker.simonis at sap.com_
> >> <mailto:volker.simonis at sap.com>>,
> >> "_ppc-aix-port-dev at openjdk.java.net_<
mailto:ppc-aix-port-dev at openjdk.java.net>"
> >> <_ppc-aix-port-dev at openjdk.java.net_<
mailto:ppc-aix-port-dev at openjdk.java.net>>,
> >> "_hotspot-compiler-dev at openjdk.java.net_<
mailto:hotspot-compiler-dev at openjdk.java.net>"
> >> <_hotspot-compiler-dev at openjdk.java.net_<
mailto:hotspot-compiler-dev at openjdk.java.net>>
> >>
> >> Subject: RE: 8213754: PPC64: Add Intrinsics for
> >> isDigit/isLowerCase/isUpperCase/isWhitespace
> >> Date: Wed, Nov 21, 2018 1:53 AM
> >>
> >> Hi Martin,
> >>
> >> Thank you for giving your helpful comments. I did
not recognize
> >> “generate_method_call_static” prevents
anyoptimizations, but I now
> >> checked it actually degraded the performance,
thanks.
> >>
> >> >Please note that we don’t have a machine, yet. So
other people will
> >> have to test.
> >> I think Gustavo can help testing this change when
its' ready.
> >>
> >> >Would it be possible to introduce more
fine-grained intrinsics such
> >> that the “slow” path is outside of them?
> >> >
> >> >Maybe you can factor out as in the following
example?
> >> >if (latin1) return isLatin1Digit(codePoint);
> >> >with isLatin1Digit as HotSpotIntrinsicCandidate.
> >> Thanks for an example, please let me try to
separate the Latin block
> >> from other blocks for some time.
> >>
> >>
> >> Best regards,
> >> --
> >> Michihiro,
> >> IBM Research - Tokyo
> >>
> >> Inactive hide details for "Doerr, Martin"
---2018/11/20 01:55:27---Hi
> >> Michihiro, first of all, thanks for working
onPower9 opt"Doerr,
> >> Martin" ---2018/11/20 01:55:27---Hi Michihiro,
first of all, thanks
> >> for working on Power9optimizations. Please note
that we don't ha
> >>
> >> From: "Doerr, Martin" <_martin.doerr at sap.com_
> >> <mailto:martin.doerr at sap.com>>
> >> To: Michihiro Horie <_HORIE at jp.ibm.com_ <
mailto:HORIE at jp.ibm.com>>,
> >> "_hotspot-compiler-dev at openjdk.java.net_<
mailto:hotspot-compiler-dev at openjdk.java.net>"
> >> <_hotspot-compiler-dev at openjdk.java.net_<
mailto:hotspot-compiler-dev at openjdk.java.net>>,
> >> "_ppc-aix-port-dev at openjdk.java.net_<
mailto:ppc-aix-port-dev at openjdk.java.net>"
> >> <_ppc-aix-port-dev at openjdk.java.net_
> >> <mailto:ppc-aix-port-dev at openjdk.java.net>>
> >> Cc: "Simonis, Volker" <_volker.simonis at sap.com_
> >> <mailto:volker.simonis at sap.com>>, "Lindenmaier,
> >> Goetz"<_goetz.lindenmaier at sap.com_
> >> <mailto:goetz.lindenmaier at sap.com>>, Gustavo Romero
> >> <_gromero at linux.vnet.ibm.com_<
mailto:gromero at linux.vnet.ibm.com>>
> >> Date: 2018/11/20 01:55
> >> Subject: RE: 8213754: PPC64: Add Intrinsics for
> >> isDigit/isLowerCase/isUpperCase/isWhitespace
> >>
> >>
>
------------------------------------------------------------------------------------------------------------------------
> >>
> >>
> >>
> >>
> >>
> >> Hi Michihiro,
> >>
> >> first of all, thanks for working on Power9
optimizations. Please note
> >> that we don’t have a machine, yet. So other
peoplewill have to test.
> >>
> >> I think it may be problematic to insert a slow path
by
> >> “generate_method_call_static”. This may be a
performancedisadvantage
> >> for some users of other encodings because your
intrinsics prevent
> >> inlining and further optimizations.
> >> Would it be possible to introduce more fine-grained
intrinsics such
> >> that the “slow” path is outside of them?
> >>
> >> Maybe you can factor out as in the following
example?
> >> if (latin1) return isLatin1Digit(codePoint);
> >> with isLatin1Digit as HotSpotIntrinsicCandidate.
> >>
> >> I can’t judge if this is needed, but I think this
should be discussed
> >> first before going into the details.
> >>
> >> Best regards,
> >> Martin
> >>
> >> *
> >> **From:*Michihiro Horie <_HORIE at jp.ibm.com_ <
mailto:HORIE at jp.ibm.com>>*
> >> **Sent:*Freitag, 16. November 2018 12:53*
> >> **To:*_hotspot-compiler-dev at openjdk.java.net_
> >> <mailto:hotspot-compiler-dev at openjdk.java.net
>;_ppc-aix-port-dev at openjdk.java.net_
> >> <mailto:ppc-aix-port-dev at openjdk.java.net>*
> >> **Cc:*Doerr, Martin <_martin.doerr at sap.com_
> >> <mailto:martin.doerr at sap.com>>; Simonis, Volker
> >> <_volker.simonis at sap.com_<
mailto:volker.simonis at sap.com>>;
> >> Lindenmaier, Goetz <_goetz.lindenmaier at sap.com_
> >> <mailto:goetz.lindenmaier at sap.com>>;Gustavo Romero
> >> <_gromero at linux.vnet.ibm.com_ <
mailto:gromero at linux.vnet.ibm.com>>*
> >> **Subject:*RFR: 8213754: PPC64: Add Intrinsics for
> >> isDigit/isLowerCase/isUpperCase/isWhitespace
> >>
> >> Dear all,
> >>
> >> Would you please review following change?
> >>
> >> Bug:
> _https://bugs.openjdk.java.net/browse/JDK-8213754_
> >> Webrev:
> _http://cr.openjdk.java.net/~mhorie/8213754/webrev.00_
>
> >> <
http://cr.openjdk.java.net/%7Emhorie/8213754/webrev.00>
> >>
> >> This change includes the intrinsics of Character
isDigit,
> >> isLowerCase, isUpperCase, and isWhitespace to
support theLatin1 block
> >> using POWER9’s instructions cmprb and cmpeqb. The
cmprb enables to
> >> compare a character with 1 or 2 rangedbytes, while
the cmpeqb
> >> compares one with 1 to 8 values. Simple micro
benchmark attached
> >> showed improvements by 20-40%.
> >> /
> >> //(See attached file: Latin1Test.java)/
> >>
> >>
> >> Best regards,
> >> --
> >> Michihiro,
> >> IBM Research - Tokyo
> >>
> >>
>
>
>
>
>
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