[--runtime-call-stats] Fix ACCESSOR handler computation

[--runtime-call-stats] Fix ACCESSOR handler computation

When running with FLAG_runtime_call_stats, native accessor accesses must
go through the runtime for accurate accounting. Previously the slow_stub()
was used as a handler in order to accomplish this, but it could never be
looked up from the code cache successfully due to mismatched code flags,
which could cause more handler recompilations than in normal operation.
This patch fixes that by emitting a runtime call into the compiled
handler instead of using the slow_stub().

Drive-by cleanup: drop the unused StoreIC_Megamorphic builtin.

Committed: https://crrev.com/31ca317af3c7c140143da616701ad45b7a08906e
Cr-Commit-Position: refs/heads/master@{#36926}

[Jakob Kummerow, 2016-06-13 10:55:11]

jkummerow@chromium.org changed reviewers:
+ cbruni@chromium.org

[Jakob Kummerow, 2016-06-13 10:55:11]

PTAL.

[Camillo Bruni, 2016-06-13 11:34:57]

LGTM for ultimate manual register allocation fun!

[Jakob Kummerow, 2016-06-13 11:36:16]

The CQ bit was checked by jkummerow@chromium.org

[commit-bot: I haz the power, 2016-06-13 11:36:19]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/2054133002/1

[commit-bot: I haz the power, 2016-06-13 11:37:49]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-06-13 11:37:50]

Try jobs failed on following builders:
  v8_linux64_asan_rel_ng on tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux64_asan_rel_ng/buil...)
  v8_linux_arm_rel_ng on tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux_arm_rel_ng/builds/...)
  v8_linux_mips64el_compile_rel on tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux_mips64el_compile_r...)
  v8_linux_mipsel_compile_rel on tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux_mipsel_compile_rel...)
  v8_win_rel_ng on tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_win_rel_ng/builds/8631)

[Jakob Kummerow, 2016-06-13 11:42:07]

The CQ bit was checked by jkummerow@chromium.org

[Jakob Kummerow, 2016-06-13 11:42:07]

The patchset sent to the CQ was uploaded after l-g-t-m from cbruni@chromium.org
Link to the patchset: https://codereview.chromium.org/2054133002/#ps20001
(title: "rebased")

[commit-bot: I haz the power, 2016-06-13 11:42:10]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/2054133002/20001

[commit-bot: I haz the power, 2016-06-13 12:11:58]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2016-06-13 12:14:26]

Description was changed from

==========
[--runtime-call-stats] Fix ACCESSOR handler computation

When running with FLAG_runtime_call_stats, native accessor accesses must
go through the runtime for accurate accounting. Previously the slow_stub()
was used as a handler in order to accomplish this, but it could never be
looked up from the code cache successfully due to mismatched code flags,
which could cause more handler recompilations than in normal operation.
This patch fixes that by emitting a runtime call into the compiled
handler instead of using the slow_stub().

Drive-by cleanup: drop the unused StoreIC_Megamorphic builtin.
==========

to

==========
[--runtime-call-stats] Fix ACCESSOR handler computation

When running with FLAG_runtime_call_stats, native accessor accesses must
go through the runtime for accurate accounting. Previously the slow_stub()
was used as a handler in order to accomplish this, but it could never be
looked up from the code cache successfully due to mismatched code flags,
which could cause more handler recompilations than in normal operation.
This patch fixes that by emitting a runtime call into the compiled
handler instead of using the slow_stub().

Drive-by cleanup: drop the unused StoreIC_Megamorphic builtin.

Committed: https://crrev.com/31ca317af3c7c140143da616701ad45b7a08906e
Cr-Commit-Position: refs/heads/master@{#36926}
==========

[commit-bot: I haz the power, 2016-06-13 12:14:28]

Patchset 2 (id:??) landed as
https://crrev.com/31ca317af3c7c140143da616701ad45b7a08906e
Cr-Commit-Position: refs/heads/master@{#36926}