Make HCheckPrototypeMaps compatible with parallel recompilation.

Make HCheckPrototypeMaps compatible with parallel recompilation.

HCheckPrototypeMaps currently records the prototype and the holder of the
prototype chain (both ends of the chain) and assumes that the chain elements
and their maps did not change in during the entirety of Crankshaft. The actual
traversal of the prototype chain happens in Lithium at code generation.
With parallel compilation, this assumption is not longer correct.

R=mstarzinger@chromium.org
BUG=

Committed: https://code.google.com/p/v8/source/detail?r=13454

[Michael Starzinger, 2013-01-15 11:12:36]

This is looking good. First round of comment. Architecture ports are still
missing.

https://chromiumcodereview.appspot.com/11864013/diff/1/src/hydrogen-instructi...
File src/hydrogen-instructions.h (right):

https://chromiumcodereview.appspot.com/11864013/diff/1/src/hydrogen-instructi...
src/hydrogen-instructions.h:2442: 
Drop the empty newline.

https://chromiumcodereview.appspot.com/11864013/diff/1/src/hydrogen-instructi...
src/hydrogen-instructions.h:2471: return true;
The original implementation of just comparing prototype and holder would still
suffice I think. But as discussed offline, it is probably safer to do a full
comparison of the whole chain anyways.

https://chromiumcodereview.appspot.com/11864013/diff/1/src/hydrogen-instructi...
src/hydrogen-instructions.h:2475: ZoneList< Handle<JSObject> > prototypes_;
The rest of the code-base doesn't have a space between the opening angles, just
between the closing.

[Yang, 2013-01-18 13:31:00]

On 2013/01/15 11:12:36, Michael Starzinger wrote:
> This is looking good. First round of comment. Architecture ports are still
> missing.
> 
>
https://chromiumcodereview.appspot.com/11864013/diff/1/src/hydrogen-instructi...
> File src/hydrogen-instructions.h (right):
> 
>
https://chromiumcodereview.appspot.com/11864013/diff/1/src/hydrogen-instructi...
> src/hydrogen-instructions.h:2442: 
> Drop the empty newline.
> 
>
https://chromiumcodereview.appspot.com/11864013/diff/1/src/hydrogen-instructi...
> src/hydrogen-instructions.h:2471: return true;
> The original implementation of just comparing prototype and holder would still
> suffice I think. But as discussed offline, it is probably safer to do a full
> comparison of the whole chain anyways.
> 
>
https://chromiumcodereview.appspot.com/11864013/diff/1/src/hydrogen-instructi...
> src/hydrogen-instructions.h:2475: ZoneList< Handle<JSObject> > prototypes_;
> The rest of the code-base doesn't have a space between the opening angles,
just
> between the closing.

Ports are implemented. Need the final green light.

[Michael Starzinger, 2013-01-21 10:58:43]

LGTM. Just one comment about the name and location of the test-case.

https://chromiumcodereview.appspot.com/11864013/diff/4001/test/mjsunit/parall...
File test/mjsunit/parallel-recompilation.js (right):

https://chromiumcodereview.appspot.com/11864013/diff/4001/test/mjsunit/parall...
test/mjsunit/parallel-recompilation.js:1: // Copyright 2013 the V8 project
authors. All rights reserved.
I think this test-case should be moved into the compiler directory where the
other Crankshaft related tests are located. And maybe name it
parallel-proto-change.js or something that indicates it's specific to
HCheckPrototypeMaps in some way.

[Yang, 2013-01-21 12:48:30]

On 2013/01/21 10:58:43, Michael Starzinger wrote:
> LGTM. Just one comment about the name and location of the test-case.
> 
>
https://chromiumcodereview.appspot.com/11864013/diff/4001/test/mjsunit/parall...
> File test/mjsunit/parallel-recompilation.js (right):
> 
>
https://chromiumcodereview.appspot.com/11864013/diff/4001/test/mjsunit/parall...
> test/mjsunit/parallel-recompilation.js:1: // Copyright 2013 the V8 project
> authors. All rights reserved.
> I think this test-case should be moved into the compiler directory where the
> other Crankshaft related tests are located. And maybe name it
> parallel-proto-change.js or something that indicates it's specific to
> HCheckPrototypeMaps in some way.

Done.