- Avoid using a streamed receive port for single messages.

- Avoid using a streamed receive port for single messages.
- Only open a single receive port for a set of load requests.
- Store information about load requests in a map, which will be able to hold
  other relevant information about the request.

BUG=
R=asiva@google.com

Committed: https://github.com/dart-lang/sdk/commit/2abc21a1bf6837ffcceef1794053b92edccd8826

[Ivan Posva, 2015-05-27 21:58:33]

Removed unused methods.

[Ivan Posva, 2015-05-27 21:59:00]

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

[siva, 2015-05-27 23:08:28]

lgtm

https://codereview.chromium.org/1154173006/diff/20001/runtime/bin/builtin.dart
File runtime/bin/builtin.dart (right):

https://codereview.chromium.org/1154173006/diff/20001/runtime/bin/builtin.dar...
runtime/bin/builtin.dart:72: // Once there are not outstanding load requests the
current load has finished.
no outstanding load

https://codereview.chromium.org/1154173006/diff/20001/runtime/bin/builtin.dar...
runtime/bin/builtin.dart:274: int id = msg[0];
assert((id > 0) && (id < _reqMap.length));

https://codereview.chromium.org/1154173006/diff/20001/runtime/bin/builtin.dar...
runtime/bin/builtin.dart:317: _reqMap[curId] = new _LoadRequest(curId, tag, uri,
libraryUri);
I understand we are single threaded and adding the request into the map after
sending the message is fine but it would be better for data consistency to order
the code as:

var curId = _reqId++;
assert(_reqMap[curId] == null);
_reqMap[curId] = new ...
var msg = new List[3];
msg[0] = ...;
msg[1] = ...
....
_loadPort.send(msg);

[Ivan Posva, 2015-05-27 23:41:32]

Thanks!
-Ivan

https://codereview.chromium.org/1154173006/diff/20001/runtime/bin/builtin.dart
File runtime/bin/builtin.dart (right):

https://codereview.chromium.org/1154173006/diff/20001/runtime/bin/builtin.dar...
runtime/bin/builtin.dart:72: // Once there are not outstanding load requests the
current load has finished.
On 2015/05/27 23:08:28, siva wrote:
> no outstanding load

Done.

https://codereview.chromium.org/1154173006/diff/20001/runtime/bin/builtin.dar...
runtime/bin/builtin.dart:274: int id = msg[0];
On 2015/05/27 23:08:28, siva wrote:
> assert((id > 0) && (id < _reqMap.length));

assert((id >= 0) && (id < _reqId));

https://codereview.chromium.org/1154173006/diff/20001/runtime/bin/builtin.dar...
runtime/bin/builtin.dart:317: _reqMap[curId] = new _LoadRequest(curId, tag, uri,
libraryUri);
On 2015/05/27 23:08:28, siva wrote:
> I understand we are single threaded and adding the request into the map after
> sending the message is fine but it would be better for data consistency to
order
> the code as:
> 
> var curId = _reqId++;
> assert(_reqMap[curId] == null);
> _reqMap[curId] = new ...
> var msg = new List[3];
> msg[0] = ...;
> msg[1] = ...
> ....
> _loadPort.send(msg);

Done.

[Ivan Posva, 2015-05-27 23:59:48]

Committed patchset #3 (id:40001) manually as
2abc21a1bf6837ffcceef1794053b92edccd8826 (presubmit successful).