Make undefined and null equivalent.

Make undefined and null equivalent.

Fixes issue 3328.

Committed: https://code.google.com/p/dart/source/detail?r=9053

[floitsch, 2012-06-15 15:19:11]

This is just a preliminary CL, but the results so far are mixed.
Some benchmarks go down by up to 20% (still have to investigate). Dromaeo
improved by ~20%. I expected more. Maybe I'm still doing something wrong.

[floitsch, 2012-06-21 09:38:13]

I can now reproduce the huge speedups in dromaeo (more than *3 on some tests).
I support Stephen's suggestion (off line) to commit now so we get the benefits
in dromaeo. We can then look at the regressions in the other benchmarks
afterwards.
I have slightly refactored the code, so PTAL.

[sra1, 2012-06-21 19:42:50]

lgtm.

https://chromiumcodereview.appspot.com/10533151/diff/7001/lib/compiler/implem...
File lib/compiler/implementation/lib/interceptors.dart (right):

https://chromiumcodereview.appspot.com/10533151/diff/7001/lib/compiler/implem...
lib/compiler/implementation/lib/interceptors.dart:453: if (fractionDigits !==
null) {
!=

[sra1, 2012-06-21 22:33:23]

still lgtm

https://chromiumcodereview.appspot.com/10533151/diff/7001/lib/compiler/implem...
File lib/compiler/implementation/lib/interceptors.dart (right):

https://chromiumcodereview.appspot.com/10533151/diff/7001/lib/compiler/implem...
lib/compiler/implementation/lib/interceptors.dart:453: if (fractionDigits !==
null) {
On 2012/06/21 19:42:50, sra1 wrote:
> !=

Sorry, this is Dart code :-)
When the new changes to == are implemented and === is removed we will need to do
this.