VM: Load-forwarding of non-final field values at allocations.

VM: Load-forwarding of non-final field values at allocations.

Instead of ignoring escaping allocations, we now forward values
for all non-final fields and type arguments even if the object
 escapes. For non-escaping objects we forward all fields.

R=vegorov@google.com

Committed: https://code.google.com/p/dart/source/detail?r=41522

[Florian Schneider, 2014-11-05 13:58:18]

fschneider@google.com changed reviewers:
+ vegorov@google.com

[Vyacheslav Egorov (Google), 2014-11-05 14:13:48]

lgtm

https://codereview.chromium.org/701113003/diff/1/runtime/vm/flow_graph_optimi...
File runtime/vm/flow_graph_optimizer.cc (right):

https://codereview.chromium.org/701113003/diff/1/runtime/vm/flow_graph_optimi...
runtime/vm/flow_graph_optimizer.cc:6340: bool forward =
!aliased_set_->CanBeAliased(alloc) ||
Maybe you can do 

if (aliased_set_->CanBeAliased(alloc) &&
    (load->field() != NULL) &&
    load->field()->is_final())) {
  continue;
}

then you don't need |forward| variable.

https://codereview.chromium.org/701113003/diff/1/runtime/vm/flow_graph_optimi...
runtime/vm/flow_graph_optimizer.cc:6351: continue;
Should not this |continue;| go away?

[Florian Schneider, 2014-11-05 14:53:43]

https://codereview.chromium.org/701113003/diff/1/runtime/vm/flow_graph_optimi...
File runtime/vm/flow_graph_optimizer.cc (right):

https://codereview.chromium.org/701113003/diff/1/runtime/vm/flow_graph_optimi...
runtime/vm/flow_graph_optimizer.cc:6340: bool forward =
!aliased_set_->CanBeAliased(alloc) ||
On 2014/11/05 14:13:47, Vyacheslav Egorov (Google) wrote:
> Maybe you can do 
> 
> if (aliased_set_->CanBeAliased(alloc) &&
>     (load->field() != NULL) &&
>     load->field()->is_final())) {
>   continue;
> }
> 
> then you don't need |forward| variable.

Done.

https://codereview.chromium.org/701113003/diff/1/runtime/vm/flow_graph_optimi...
runtime/vm/flow_graph_optimizer.cc:6351: continue;
On 2014/11/05 14:13:47, Vyacheslav Egorov (Google) wrote:
> Should not this |continue;| go away?

Done.

[Florian Schneider, 2014-11-05 15:23:04]

Committed patchset #2 (id:20001) manually as r41522 (presubmit successful).