Improve condition strengthening for last test in short-circuit.

Improve condition strengthening for last test in short-circuit.

This strengthens

   t1 = s == null || t == null;
   if (t1) return;
   known-here:  t != null

There are not many hits since the 'interesting' tests are usually
earlier in the short-circuit expression.

R=sigmund@google.com

Committed: https://github.com/dart-lang/sdk/commit/7eaad70e2fdbf9dc118e3243877761f7632b9095

[sra1, 2016-10-21 04:50:52]

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

[Siggi Cherem (dart-lang), 2016-10-21 14:31:15]

lgtm!

[sra1, 2016-10-25 11:48:48]

Description was changed from

==========
Improve condition strengthening for last test in short-circuit.

This strengthens

   t1 = s == null || t == null;
   if (t1) return;
   known-here:  t != null

There are not many hits since the 'interesting' tests are usually
earlier in the short-circuit expression.
==========

to

==========
Improve condition strengthening for last test in short-circuit.

This strengthens

   t1 = s == null || t == null;
   if (t1) return;
   known-here:  t != null

There are not many hits since the 'interesting' tests are usually
earlier in the short-circuit expression.

R=sigmund@google.com

Committed:
https://github.com/dart-lang/sdk/commit/7eaad70e2fdbf9dc118e3243877761f7632b9095
==========

[sra1, 2016-10-25 11:48:49]

Committed patchset #2 (id:20001) manually as
7eaad70e2fdbf9dc118e3243877761f7632b9095 (presubmit successful).