Abort tracing in type inference in the presence of await.

Abort tracing in type inference in the presence of await.

BUG= http://dartbug.com/22868 http://dartbug.com/22895
R=floitsch@google.com

Committed: https://code.google.com/p/dart/source/detail?r=44555

Reverted: https://code.google.com/p/dart/source/detail?r=44556

Committed: https://code.google.com/p/dart/source/detail?r=44573

[herhut, 2015-03-17 15:25:41]

herhut@google.com changed reviewers:
+ floitsch@google.com

[floitsch, 2015-03-17 18:14:10]

LGTM.

https://codereview.chromium.org/1013803006/diff/1/pkg/compiler/lib/src/inferr...
File pkg/compiler/lib/src/inferrer/simple_types_inferrer.dart (right):

https://codereview.chromium.org/1013803006/diff/1/pkg/compiler/lib/src/inferr...
pkg/compiler/lib/src/inferrer/simple_types_inferrer.dart:1020: // TODO(herhut):
Return a better type here if possible.
Comment should probably be on the implementing function.

https://codereview.chromium.org/1013803006/diff/1/pkg/compiler/lib/src/inferr...
File pkg/compiler/lib/src/inferrer/type_graph_nodes.dart (right):

https://codereview.chromium.org/1013803006/diff/1/pkg/compiler/lib/src/inferr...
pkg/compiler/lib/src/inferrer/type_graph_nodes.dart:1527: TypeMask
computeType(TypeGraphInferrerEngine inferrer) => safeType(inferrer);
In theory you could do better here:
if it's a concrete type that isn't implementing Future -> use that type.
Otherwise -> dynamic.

[herhut, 2015-03-18 10:35:08]

https://codereview.chromium.org/1013803006/diff/1/pkg/compiler/lib/src/inferr...
File pkg/compiler/lib/src/inferrer/simple_types_inferrer.dart (right):

https://codereview.chromium.org/1013803006/diff/1/pkg/compiler/lib/src/inferr...
pkg/compiler/lib/src/inferrer/simple_types_inferrer.dart:1020: // TODO(herhut):
Return a better type here if possible.
On 2015/03/17 18:14:09, floitsch wrote:
> Comment should probably be on the implementing function.

Done.

https://codereview.chromium.org/1013803006/diff/1/pkg/compiler/lib/src/inferr...
File pkg/compiler/lib/src/inferrer/type_graph_nodes.dart (right):

https://codereview.chromium.org/1013803006/diff/1/pkg/compiler/lib/src/inferr...
pkg/compiler/lib/src/inferrer/type_graph_nodes.dart:1527: TypeMask
computeType(TypeGraphInferrerEngine inferrer) => safeType(inferrer);
On 2015/03/17 18:14:09, floitsch wrote:
> In theory you could do better here:
> if it's a concrete type that isn't implementing Future -> use that type.
> Otherwise -> dynamic.

I have filed a bug for this. I expect this scenario (awaiting on something that
does not return a future) to be quite rare anyway. 

Lets keep this simple for now as this is supposed to be merged into 1.9.

[herhut, 2015-03-18 10:36:09]

Committed patchset #2 (id:20001) manually as 44555 (presubmit successful).

[herhut, 2015-03-18 13:32:05]

PTAL

[floitsch, 2015-03-18 14:47:43]

Still LGTM.

[herhut, 2015-03-19 09:12:16]

PTAL

I had forgotten what side effects hasStableType has. While Awaits have a stable
type, hasStableType will also trigger the destruction of the flow graph at that
point, thereby inhibiting proper tracing :(

I'll do another CL to clean hasStableType up a bit but I want to keep this small
for merging into 1.9.

[floitsch, 2015-03-19 10:30:54]

Still LGTM.

[herhut, 2015-03-19 12:58:35]

Patchset #5 (id:80001) has been deleted

[herhut, 2015-03-19 13:21:42]

Committed patchset #5 (id:100001) manually as 44573 (presubmit successful).