[turbofan] Desugar JSUnaryNot(x) to Select(x, false, true).

[turbofan] Desugar JSUnaryNot(x) to Select(x, false, true).

Also remove the ResultMode from ToBooleanStub and always return true or
false and use the same mechanism in fullcodegen.  This is in preparation
for adding ToBoolean hints to TurboFan.

Drive-by-fix: We can use the power of the ToBooleanIC in TurboFan now
that the ResultMode is gone (and the runtime always returns true or
false from the miss handler).

R=mstarzinger@chromium.org
BUG=v8:4583
LOG=n

Committed: https://crrev.com/411c5b7fb09f76fca567c3deda3304f77eb3df2f
Cr-Commit-Position: refs/heads/master@{#32524}

[Benedikt Meurer, 2015-12-02 13:43:36]

Hey Michi,

Here's the refactoring for JSUnaryNot we talked about earlier. The idea is that
ToBoolean is the bottleneck for ToBoolean hints in TurboFan (extracted from the
IC). As additional bonus we can now use the learning IC in TurboFan, which gives
a small performance boost on some things as well.
Please take a look.

Thanks,
Benedikt

[Michael Starzinger, 2015-12-02 15:12:50]

LGTM. I like it.

[Michael Starzinger, 2015-12-02 15:12:56]

The CQ bit was checked by mstarzinger@chromium.org

[commit-bot: I haz the power, 2015-12-02 15:13:06]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1491223002/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1491223002/20001

[commit-bot: I haz the power, 2015-12-02 15:21:50]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-12-02 15:22:21]

Description was changed from

==========
[turbofan] Desugar JSUnaryNot(x) to Select(x, false, true).

Also remove the ResultMode from ToBooleanStub and always return true or
false and use the same mechanism in fullcodegen.  This is in preparation
for adding ToBoolean hints to TurboFan.

Drive-by-fix: We can use the power of the ToBooleanIC in TurboFan now
that the ResultMode is gone (and the runtime always returns true or
false from the miss handler).

R=mstarzinger@chromium.org
BUG=v8:4583
LOG=n
==========

to

==========
[turbofan] Desugar JSUnaryNot(x) to Select(x, false, true).

Also remove the ResultMode from ToBooleanStub and always return true or
false and use the same mechanism in fullcodegen.  This is in preparation
for adding ToBoolean hints to TurboFan.

Drive-by-fix: We can use the power of the ToBooleanIC in TurboFan now
that the ResultMode is gone (and the runtime always returns true or
false from the miss handler).

R=mstarzinger@chromium.org
BUG=v8:4583
LOG=n

Committed: https://crrev.com/411c5b7fb09f76fca567c3deda3304f77eb3df2f
Cr-Commit-Position: refs/heads/master@{#32524}
==========

[commit-bot: I haz the power, 2015-12-02 15:22:22]

Patchset 2 (id:??) landed as
https://crrev.com/411c5b7fb09f76fca567c3deda3304f77eb3df2f
Cr-Commit-Position: refs/heads/master@{#32524}