Protect types_propagation receiver type strengthening against many users.

Protect types_propagation receiver type strengthening against many users.

receiver.dominatedUsers(instruction) is slow if [instruction] is in a
block with thousands of uses of [receiver].  I this case, it makes
sense to see if the type would be strengthened first.

10x performance increase on compiling MicroClosures benchmark which has 5k lines like the following two:

    a.add(this.f1234);
    a.add(this.f1235);

R=sigmund@google.com, het@google.com

Committed: https://github.com/dart-lang/sdk/commit/07184079197a999f8e138738fa81f6558f3e34da

Reverted:  https://github.com/dart-lang/sdk/commit/d63577da675f00e7a9115c7778557d9b186f809d
Committed: https://github.com/dart-lang/sdk/commit/52ecac4ed50cd25d5cf1def3e9bfcf1c6a83d133

[sra1, 2016-08-24 02:36:40]

Description was changed from

==========
Protect types_propagation receiver type strengthening against many users.

receiver.dominatedUsers(instruction) is slow if [instruction] is in a
block with thousands of uses of [receiver].  I this case, it makes
sense to see if the type would be strengthened first.

10x performance increase on compiling MicroClosures test.

R=het@google.com
==========

to

==========
Protect types_propagation receiver type strengthening against many users.

receiver.dominatedUsers(instruction) is slow if [instruction] is in a
block with thousands of uses of [receiver].  I this case, it makes
sense to see if the type would be strengthened first.

10x performance increase on compiling MicroClosures test which has 5k lines like
the following two:

    a.add(this.f1234);
    a.add(this.f1235);


R=het@google.com
==========

[sra1, 2016-08-24 20:05:37]

Description was changed from

==========
Protect types_propagation receiver type strengthening against many users.

receiver.dominatedUsers(instruction) is slow if [instruction] is in a
block with thousands of uses of [receiver].  I this case, it makes
sense to see if the type would be strengthened first.

10x performance increase on compiling MicroClosures test which has 5k lines like
the following two:

    a.add(this.f1234);
    a.add(this.f1235);


R=het@google.com
==========

to

==========
Protect types_propagation receiver type strengthening against many users.

receiver.dominatedUsers(instruction) is slow if [instruction] is in a
block with thousands of uses of [receiver].  I this case, it makes
sense to see if the type would be strengthened first.

10x performance increase on compiling MicroClosures benchmark which has 5k lines
like the following two:

    a.add(this.f1234);
    a.add(this.f1235);


R=het@google.com
==========

[sra1, 2016-08-24 20:18:58]

sra@google.com changed reviewers:
+ sigmund@google.com

[Siggi Cherem (dart-lang), 2016-08-24 21:25:29]

lgtm

[sra1, 2016-08-25 19:28:41]

Description was changed from

==========
Protect types_propagation receiver type strengthening against many users.

receiver.dominatedUsers(instruction) is slow if [instruction] is in a
block with thousands of uses of [receiver].  I this case, it makes
sense to see if the type would be strengthened first.

10x performance increase on compiling MicroClosures benchmark which has 5k lines
like the following two:

    a.add(this.f1234);
    a.add(this.f1235);


R=het@google.com
==========

to

==========
Protect types_propagation receiver type strengthening against many users.

receiver.dominatedUsers(instruction) is slow if [instruction] is in a
block with thousands of uses of [receiver].  I this case, it makes
sense to see if the type would be strengthened first.

10x performance increase on compiling MicroClosures benchmark which has 5k lines
like the following two:

    a.add(this.f1234);
    a.add(this.f1235);

R=sigmund@google.com, het@google.com

Committed:
https://github.com/dart-lang/sdk/commit/07184079197a999f8e138738fa81f6558f3e34da
==========

[sra1, 2016-08-25 19:28:42]

Committed patchset #1 (id:1) manually as
07184079197a999f8e138738fa81f6558f3e34da (presubmit successful).

[Siggi Cherem (dart-lang), 2016-08-26 00:46:15]

it appears that this broke a test: 
  python tools/test.py -mrelease -cdart2js  -rd8   
language/type_propagation3_test

I haven't looked into why yet, but reverting the change makes the test pass.

[sra1, 2016-08-26 02:27:55]

Description was changed from

==========
Protect types_propagation receiver type strengthening against many users.

receiver.dominatedUsers(instruction) is slow if [instruction] is in a
block with thousands of uses of [receiver].  I this case, it makes
sense to see if the type would be strengthened first.

10x performance increase on compiling MicroClosures benchmark which has 5k lines
like the following two:

    a.add(this.f1234);
    a.add(this.f1235);

R=sigmund@google.com, het@google.com

Committed:
https://github.com/dart-lang/sdk/commit/07184079197a999f8e138738fa81f6558f3e34da
==========

to

==========
Protect types_propagation receiver type strengthening against many users.

receiver.dominatedUsers(instruction) is slow if [instruction] is in a
block with thousands of uses of [receiver].  I this case, it makes
sense to see if the type would be strengthened first.

10x performance increase on compiling MicroClosures benchmark which has 5k lines
like the following two:

    a.add(this.f1234);
    a.add(this.f1235);

R=sigmund@google.com, het@google.com

Committed:
https://github.com/dart-lang/sdk/commit/07184079197a999f8e138738fa81f6558f3e34da

Reverted: 
https://github.com/dart-lang/sdk/commit/d63577da675f00e7a9115c7778557d9b186f809d
==========

[sra1, 2016-08-26 03:10:18]

On 2016/08/26 00:46:15, Siggi Cherem (dart-lang) wrote:
> it appears that this broke a test: 
>   python tools/test.py -mrelease -cdart2js  -rd8   
> language/type_propagation3_test
> 
> I haven't looked into why yet, but reverting the change makes the test pass.

I have reverted for now.

[sra1, 2016-08-26 03:47:12]

PTAL

[Siggi Cherem (dart-lang), 2016-08-26 15:46:34]

https://codereview.chromium.org/2275853002/diff/40001/pkg/compiler/lib/src/ss...
File pkg/compiler/lib/src/ssa/types_propagation.dart (right):

https://codereview.chromium.org/2275853002/diff/40001/pkg/compiler/lib/src/ss...
pkg/compiler/lib/src/ssa/types_propagation.dart:387: if (next.instructionType !=
computeNewType()) {
originally this update was only done when `hasCandidates` was true, don't we
need to still check that?

If so, consider adding yet another helper function that does the check in the
optimal order. For instance:

bool check(oldType) =>
  (receiver.usedBy.length <= _MAX_QUICK_USERS)
  ? (hasCandidates() && computeNewType() != oldType)
  : (computeNewType() != oldType && hasCandidates()));

...


Then you can call it here as:
  check(next.instructionType)

and below as:
  check(receiverType)

[Siggi Cherem (dart-lang), 2016-08-26 17:03:48]

we discussed this offline, lgtm!

[sra1, 2016-08-29 17:58:19]

Description was changed from

==========
Protect types_propagation receiver type strengthening against many users.

receiver.dominatedUsers(instruction) is slow if [instruction] is in a
block with thousands of uses of [receiver].  I this case, it makes
sense to see if the type would be strengthened first.

10x performance increase on compiling MicroClosures benchmark which has 5k lines
like the following two:

    a.add(this.f1234);
    a.add(this.f1235);

R=sigmund@google.com, het@google.com

Committed:
https://github.com/dart-lang/sdk/commit/07184079197a999f8e138738fa81f6558f3e34da

Reverted: 
https://github.com/dart-lang/sdk/commit/d63577da675f00e7a9115c7778557d9b186f809d
==========

to

==========
Protect types_propagation receiver type strengthening against many users.

receiver.dominatedUsers(instruction) is slow if [instruction] is in a
block with thousands of uses of [receiver].  I this case, it makes
sense to see if the type would be strengthened first.

10x performance increase on compiling MicroClosures benchmark which has 5k lines
like the following two:

    a.add(this.f1234);
    a.add(this.f1235);

R=sigmund@google.com, het@google.com

Committed:
https://github.com/dart-lang/sdk/commit/07184079197a999f8e138738fa81f6558f3e34da

Reverted: 
https://github.com/dart-lang/sdk/commit/d63577da675f00e7a9115c7778557d9b186f809d
Committed:
https://github.com/dart-lang/sdk/commit/52ecac4ed50cd25d5cf1def3e9bfcf1c6a83d133
==========

[sra1, 2016-08-29 17:58:20]

Committed patchset #4 (id:60001) manually as
52ecac4ed50cd25d5cf1def3e9bfcf1c6a83d133 (presubmit successful).