Use symbols when looking up fields in a class

Use symbols when looking up fields in a class

The slow string comparison is only necessary when looking up
non-symbols or untangled private names.

Compiling all of dart2js seems to be about 1% faster, but it's really in the noise.

BUG=
R=asiva@google.com

Committed: https://github.com/dart-lang/sdk/commit/425b9a36b9075c3bf5269575ead9d041699a4f36

[hausner, 2016-04-06 23:38:28]

Description was changed from

==========
Use symbols when looking up fields in a class

The slow string comparison is only necessary when looking up
non-symbols or untangled private names.

BUG=
==========

to

==========
Use symbols when looking up fields in a class

The slow string comparison is only necessary when looking up
non-symbols or untangled private names.

Compiling all of dart2js seems to be about 1% faster, but it's really in the
noise.

BUG=
==========

[hausner, 2016-04-06 23:38:28]

hausner@google.com changed reviewers:
+ asiva@google.com

[siva, 2016-04-07 22:51:30]

lgtm

https://chromiumcodereview.appspot.com/1868803002/diff/40001/runtime/vm/objec...
File runtime/vm/object.cc (right):

https://chromiumcodereview.appspot.com/1868803002/diff/40001/runtime/vm/objec...
runtime/vm/object.cc:4190: return field.raw();
Not sure if it is worth extracting the code inside the if block into :

static RawField* getField(MemberKind kind, const Field& field) { ... }

and do return getField(kind, field); in the two places.

[hausner, 2016-04-07 23:36:39]

Description was changed from

==========
Use symbols when looking up fields in a class

The slow string comparison is only necessary when looking up
non-symbols or untangled private names.

Compiling all of dart2js seems to be about 1% faster, but it's really in the
noise.

BUG=
==========

to

==========
Use symbols when looking up fields in a class

The slow string comparison is only necessary when looking up
non-symbols or untangled private names.

Compiling all of dart2js seems to be about 1% faster, but it's really in the
noise.

BUG=
R=asiva@google.com

Committed:
https://github.com/dart-lang/sdk/commit/425b9a36b9075c3bf5269575ead9d041699a4f36
==========

[hausner, 2016-04-07 23:36:40]

Committed patchset #3 (id:40001) manually as
425b9a36b9075c3bf5269575ead9d041699a4f36 (presubmit successful).

[hausner, 2016-04-07 23:37:03]

Thank you.

https://chromiumcodereview.appspot.com/1868803002/diff/40001/runtime/vm/objec...
File runtime/vm/object.cc (right):

https://chromiumcodereview.appspot.com/1868803002/diff/40001/runtime/vm/objec...
runtime/vm/object.cc:4190: return field.raw();
On 2016/04/07 22:51:30, siva wrote:
> Not sure if it is worth extracting the code inside the if block into :
> 
> static RawField* getField(MemberKind kind, const Field& field) { ... }
> 
> and do return getField(kind, field); in the two places.

I hesitate to create a mini function to factor out 5 lines of code that
otherwise don't have any use. In the *AllowPrivate version of this function, I
pulled this check out into the caller. That requires the caller to allocate
another Handle to do the is_static() check. I didn't want that for the fast
path.

If you insist, I'll do it in a follow-up CL.

[sra1, 2016-04-08 20:30:05]

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

[sra1, 2016-04-08 20:30:06]

https://chromiumcodereview.appspot.com/1868803002/diff/40001/runtime/vm/objec...
File runtime/vm/object.cc (right):

https://chromiumcodereview.appspot.com/1868803002/diff/40001/runtime/vm/objec...
runtime/vm/object.cc:9477: name.CharAt(3) == ':'));
Testing ':' before 'g' / 's' will fail faster.

[hausner, 2016-04-08 20:41:20]

https://chromiumcodereview.appspot.com/1868803002/diff/40001/runtime/vm/objec...
File runtime/vm/object.cc (right):

https://chromiumcodereview.appspot.com/1868803002/diff/40001/runtime/vm/objec...
runtime/vm/object.cc:9477: name.CharAt(3) == ':'));
On 2016/04/08 20:30:06, sra1 wrote:
> Testing ':' before 'g' / 's' will fail faster.

The test (name.CharAt(4) == '_') eliminates practically all non-getter and
non-setter names. I would not lose sleep over this :)