Stop overallocating feedback vector slots.

Stop overallocating feedback vector slots.

When a Property or a VariableProxy is used as the left hand side of an
assignment statement, there is no need to allocate a LOAD_IC feedback
vector slot for it. Alter the numbering phase to support this.

BUG=

Committed: https://crrev.com/f469b21143b812aad1ea92ae730f5b7d36b3c702
Cr-Commit-Position: refs/heads/master@{#29924}

[mvstanton, 2015-07-29 12:39:27]

Hi Benedikt,
Here is a fix for the bug we saw the other day, where an IC slot is foolishly
allocated for a VariableProxy on the LHS of an assignment operation. (also
Property).
Thanks for the look,
--Michael

[mvstanton, 2015-07-29 12:39:48]

mvstanton@chromium.org changed reviewers:
+ bmeurer@chromium.org

[mvstanton, 2015-07-29 12:39:48]

Hi Benedikt,
Here is a fix for the bug we saw the other day, where an IC slot is foolishly
allocated for a VariableProxy on the LHS of an assignment operation. (also
Property).
Thanks for the look,
--Michael

[Benedikt Meurer, 2015-07-30 06:32:22]

Awesome! LGTM with nit.

https://codereview.chromium.org/1262803002/diff/1/src/ast-numbering.cc
File src/ast-numbering.cc (right):

https://codereview.chromium.org/1262803002/diff/1/src/ast-numbering.cc#newcod...
src/ast-numbering.cc:326: if (expr->IsProperty())
Nit: if { ... } else { ... }

[mvstanton, 2015-07-30 09:28:47]

The CQ bit was checked by mvstanton@chromium.org

[mvstanton, 2015-07-30 09:28:48]

The patchset sent to the CQ was uploaded after l-g-t-m from bmeurer@chromium.org
Link to the patchset: https://codereview.chromium.org/1262803002/#ps20001
(title: "Fixed nit.")

[commit-bot: I haz the power, 2015-07-30 09:28:52]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1262803002/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1262803002/20001

[commit-bot: I haz the power, 2015-07-30 10:38:03]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-07-30 10:38:16]

Patchset 2 (id:??) landed as
https://crrev.com/f469b21143b812aad1ea92ae730f5b7d36b3c702
Cr-Commit-Position: refs/heads/master@{#29924}