[turbofan][x64] Improve code generation for Float64LessThan with Float64Abs.

[turbofan][x64] Improve code generation for Float64LessThan with Float64Abs.

During instruction selection, match the pattern

  Float64LessThan(#0.0, Float64Abs(x))

which TurboFan generates for NumberToBoolean in the general case,
and which evaluates to false if x is 0, -0 or NaN, and compile this
to a simple (v)ucomisd using not_equal flags condition, which avoids
the costly Float64Abs.

Also consistently generate this pattern in TurboFan and the code
stubs/interpreter for ToBoolean.

R=mstarzinger@chromium.org
BUG=v8:5267
Committed: https://crrev.com/cdf9a4062ec6aa8f7c180e3f3e9f5c7130eb199a
Cr-Commit-Position: refs/heads/master@{#40740}

[Benedikt Meurer, 2016-11-03 13:43:47]

The CQ bit was checked by bmeurer@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2016-11-03 13:43:51]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[Michael Starzinger, 2016-11-03 13:47:25]

LGTM (rubber-stamped).

[Benedikt Meurer, 2016-11-03 13:47:37]

The CQ bit was unchecked by bmeurer@chromium.org

[Benedikt Meurer, 2016-11-03 13:47:40]

The CQ bit was checked by bmeurer@chromium.org

[commit-bot: I haz the power, 2016-11-03 13:47:52]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-11-03 14:03:43]

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

[commit-bot: I haz the power, 2016-11-03 14:03:43]

Try jobs failed on following builders:
  v8_linux64_avx2_rel_ng on master.tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux64_avx2_rel_ng/buil...)
  v8_linux64_avx2_rel_ng_triggered on master.tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux64_avx2_rel_ng_trig...)

[Benedikt Meurer, 2016-11-03 16:09:46]

The CQ bit was checked by bmeurer@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2016-11-03 16:09:55]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[Benedikt Meurer, 2016-11-03 16:10:22]

Description was changed from

==========
[turbofan][x64] Improve code generation for Float64LessThan with Float64Abs.

During instruction selection, match the pattern

  Float64LessThan(#0.0, Float64Abs(x))

which TurboFan generates for NumberToBoolean in the general case,
and which evaluates to false if x is 0, -0 or NaN, and compile this
to a simple (v)ucomisd using not_equal flags condition, which avoids
the costly Float64Abs.

R=mstarzinger@chromium.org
BUG=v8:5267
==========

to

==========
[turbofan][x64] Improve code generation for Float64LessThan with Float64Abs.

During instruction selection, match the pattern

  Float64LessThan(#0.0, Float64Abs(x))

which TurboFan generates for NumberToBoolean in the general case,
and which evaluates to false if x is 0, -0 or NaN, and compile this
to a simple (v)ucomisd using not_equal flags condition, which avoids
the costly Float64Abs.

Also consistently generate this pattern in TurboFan and the code
stubs/interpreter for ToBoolean.

R=mstarzinger@chromium.org
BUG=v8:5267
==========

[Benedikt Meurer, 2016-11-03 16:10:43]

The CQ bit was unchecked by bmeurer@chromium.org

[Benedikt Meurer, 2016-11-03 16:10:48]

The CQ bit was checked by bmeurer@chromium.org

[Benedikt Meurer, 2016-11-03 16:10:48]

The patchset sent to the CQ was uploaded after l-g-t-m from
mstarzinger@chromium.org
Link to the patchset: https://codereview.chromium.org/2473923003/#ps20001
(title: "Fix")

[commit-bot: I haz the power, 2016-11-03 16:10:58]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-11-03 16:14:04]

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

[commit-bot: I haz the power, 2016-11-03 16:14:05]

Try jobs failed on following builders:
  v8_linux64_gyp_rel_ng on master.tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux64_gyp_rel_ng/build...)

[Benedikt Meurer, 2016-11-03 18:20:09]

The CQ bit was checked by bmeurer@chromium.org

[Benedikt Meurer, 2016-11-03 18:20:10]

The patchset sent to the CQ was uploaded after l-g-t-m from
mstarzinger@chromium.org
Link to the patchset: https://codereview.chromium.org/2473923003/#ps40001
(title: "Fix for realz.")

[commit-bot: I haz the power, 2016-11-03 18:20:18]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-11-03 18:47:26]

Description was changed from

==========
[turbofan][x64] Improve code generation for Float64LessThan with Float64Abs.

During instruction selection, match the pattern

  Float64LessThan(#0.0, Float64Abs(x))

which TurboFan generates for NumberToBoolean in the general case,
and which evaluates to false if x is 0, -0 or NaN, and compile this
to a simple (v)ucomisd using not_equal flags condition, which avoids
the costly Float64Abs.

Also consistently generate this pattern in TurboFan and the code
stubs/interpreter for ToBoolean.

R=mstarzinger@chromium.org
BUG=v8:5267
==========

to

==========
[turbofan][x64] Improve code generation for Float64LessThan with Float64Abs.

During instruction selection, match the pattern

  Float64LessThan(#0.0, Float64Abs(x))

which TurboFan generates for NumberToBoolean in the general case,
and which evaluates to false if x is 0, -0 or NaN, and compile this
to a simple (v)ucomisd using not_equal flags condition, which avoids
the costly Float64Abs.

Also consistently generate this pattern in TurboFan and the code
stubs/interpreter for ToBoolean.

R=mstarzinger@chromium.org
BUG=v8:5267
==========

[commit-bot: I haz the power, 2016-11-03 18:47:27]

Committed patchset #3 (id:40001)

[commit-bot: I haz the power, 2016-11-17 22:21:26]

Description was changed from

==========
[turbofan][x64] Improve code generation for Float64LessThan with Float64Abs.

During instruction selection, match the pattern

  Float64LessThan(#0.0, Float64Abs(x))

which TurboFan generates for NumberToBoolean in the general case,
and which evaluates to false if x is 0, -0 or NaN, and compile this
to a simple (v)ucomisd using not_equal flags condition, which avoids
the costly Float64Abs.

Also consistently generate this pattern in TurboFan and the code
stubs/interpreter for ToBoolean.

R=mstarzinger@chromium.org
BUG=v8:5267
==========

to

==========
[turbofan][x64] Improve code generation for Float64LessThan with Float64Abs.

During instruction selection, match the pattern

  Float64LessThan(#0.0, Float64Abs(x))

which TurboFan generates for NumberToBoolean in the general case,
and which evaluates to false if x is 0, -0 or NaN, and compile this
to a simple (v)ucomisd using not_equal flags condition, which avoids
the costly Float64Abs.

Also consistently generate this pattern in TurboFan and the code
stubs/interpreter for ToBoolean.

R=mstarzinger@chromium.org
BUG=v8:5267

Committed: https://crrev.com/cdf9a4062ec6aa8f7c180e3f3e9f5c7130eb199a
Cr-Commit-Position: refs/heads/master@{#40740}
==========

[commit-bot: I haz the power, 2016-11-17 22:21:27]

Patchset 3 (id:??) landed as
https://crrev.com/cdf9a4062ec6aa8f7c180e3f3e9f5c7130eb199a
Cr-Commit-Position: refs/heads/master@{#40740}