[turbofan] optimize spills in defered blocks

[turbofan] optimize spills in defered blocks

Up to now, for ranges spilled in deferred blocks, we would spill every
time a range would switch from using a register to spill slots. That can
be redundant, leading to avoidable code size  cost.

This change addresses this issue, by performing the spills as early as
possible.

BUG=

Committed: https://crrev.com/7c54dc33855b8ac31f26b309671f9b5481a74376
Cr-Commit-Position: refs/heads/master@{#33413}

[Mircea Trofin, 2015-12-31 05:02:37]

Patchset #1 (id:1) has been deleted

[Mircea Trofin, 2016-01-19 04:12:43]

Patchset #1 (id:20001) has been deleted

[Mircea Trofin, 2016-01-19 04:12:53]

Patchset #1 (id:40001) has been deleted

[Mircea Trofin, 2016-01-19 04:13:05]

Patchset #1 (id:60001) has been deleted

[Mircea Trofin, 2016-01-19 04:13:17]

Patchset #1 (id:80001) has been deleted

[Mircea Trofin, 2016-01-19 04:13:26]

Patchset #1 (id:100001) has been deleted

[Mircea Trofin, 2016-01-19 04:13:37]

Patchset #1 (id:120001) has been deleted

[Mircea Trofin, 2016-01-19 04:13:49]

Patchset #1 (id:140001) has been deleted

[Mircea Trofin, 2016-01-19 04:14:06]

Patchset #1 (id:160001) has been deleted

[Mircea Trofin, 2016-01-19 04:14:19]

Patchset #1 (id:180001) has been deleted

[Mircea Trofin, 2016-01-19 04:24:30]

Description was changed from

==========
optimize spills in defered blocks

BUG=
==========

to

==========
Up to now, for ranges spilled in deferred blocks, we would spill every
time a range would switch from using a register to spill slots. That can 
be redundant, leading to avoidable code size  cost.

This change addresses this issue, by performing the spills as early as 
possible.

BUG=
==========

[Mircea Trofin, 2016-01-19 04:24:31]

mtrofin@chromium.org changed reviewers:
+ bmeurer@chromium.org, jarin@chromium.org

[Benedikt Meurer, 2016-01-20 06:06:16]

Description was changed from

==========
Up to now, for ranges spilled in deferred blocks, we would spill every
time a range would switch from using a register to spill slots. That can 
be redundant, leading to avoidable code size  cost.

This change addresses this issue, by performing the spills as early as 
possible.

BUG=
==========

to

==========
[turbofan] optimize spills in defered blocks

Up to now, for ranges spilled in deferred blocks, we would spill every
time a range would switch from using a register to spill slots. That can 
be redundant, leading to avoidable code size  cost.

This change addresses this issue, by performing the spills as early as 
possible.

BUG=
==========

[Jarin, 2016-01-20 14:07:55]

lgtm.

https://codereview.chromium.org/1551013002/diff/220001/src/compiler/register-...
File src/compiler/register-allocator.cc (right):

https://codereview.chromium.org/1551013002/diff/220001/src/compiler/register-...
src/compiler/register-allocator.cc:3341: // We're doing a fill.
Why is this called 'fill'? In literature, the moves from spill slot to register
are called 'reload'. Could not we call it that?

[Mircea Trofin, 2016-01-20 15:57:08]

Fill -> reload

https://codereview.chromium.org/1551013002/diff/220001/src/compiler/register-...
File src/compiler/register-allocator.cc (right):

https://codereview.chromium.org/1551013002/diff/220001/src/compiler/register-...
src/compiler/register-allocator.cc:3341: // We're doing a fill.
On 2016/01/20 14:07:55, Jarin wrote:
> Why is this called 'fill'? In literature, the moves from spill slot to
register
> are called 'reload'. Could not we call it that?

Sounds good!

[Mircea Trofin, 2016-01-20 15:57:15]

The CQ bit was checked by mtrofin@chromium.org

[Mircea Trofin, 2016-01-20 15:57:16]

The patchset sent to the CQ was uploaded after l-g-t-m from jarin@chromium.org
Link to the patchset: https://codereview.chromium.org/1551013002/#ps240001
(title: " ")

[commit-bot: I haz the power, 2016-01-20 15:57:27]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1551013002/240001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1551013002/240001

[commit-bot: I haz the power, 2016-01-20 16:31:22]

Description was changed from

==========
[turbofan] optimize spills in defered blocks

Up to now, for ranges spilled in deferred blocks, we would spill every
time a range would switch from using a register to spill slots. That can 
be redundant, leading to avoidable code size  cost.

This change addresses this issue, by performing the spills as early as 
possible.

BUG=
==========

to

==========
[turbofan] optimize spills in defered blocks

Up to now, for ranges spilled in deferred blocks, we would spill every
time a range would switch from using a register to spill slots. That can 
be redundant, leading to avoidable code size  cost.

This change addresses this issue, by performing the spills as early as 
possible.

BUG=
==========

[commit-bot: I haz the power, 2016-01-20 16:31:23]

Committed patchset #3 (id:240001)

[commit-bot: I haz the power, 2016-01-20 16:31:56]

Description was changed from

==========
[turbofan] optimize spills in defered blocks

Up to now, for ranges spilled in deferred blocks, we would spill every
time a range would switch from using a register to spill slots. That can 
be redundant, leading to avoidable code size  cost.

This change addresses this issue, by performing the spills as early as 
possible.

BUG=
==========

to

==========
[turbofan] optimize spills in defered blocks

Up to now, for ranges spilled in deferred blocks, we would spill every
time a range would switch from using a register to spill slots. That can
be redundant, leading to avoidable code size  cost.

This change addresses this issue, by performing the spills as early as
possible.

BUG=

Committed: https://crrev.com/7c54dc33855b8ac31f26b309671f9b5481a74376
Cr-Commit-Position: refs/heads/master@{#33413}
==========

[commit-bot: I haz the power, 2016-01-20 16:31:57]

Patchset 3 (id:??) landed as
https://crrev.com/7c54dc33855b8ac31f26b309671f9b5481a74376
Cr-Commit-Position: refs/heads/master@{#33413}

[Jarin, 2016-01-21 12:06:04]

A revert of this CL (patchset #3 id:240001) has been created in
https://codereview.chromium.org/1612013002/ by jarin@chromium.org.

The reason for reverting is: Regresses lots of benchmarks:
https://crbug.com/579900.