[builtins] Provide Math.floor as TurboFan builtin.

[builtins] Provide Math.floor as TurboFan builtin.

This way we avoid the second deoptimization for the Math.floor and
Math.ceil builtins when -0 is involved. We still deoptimize the inlined
Crankshaft version in various cases, that's a separate issue.

The algorithm used for implement CodeStubAssembler::Float64Floor is
vaguely based on the fast math version used in the libm of various BSDs,
but had to be reengineered to match the EcmaScript specification.

R=epertoso@chromium.org
BUG=v8:2890, v8:4059
LOG=n

Committed: https://crrev.com/36ead519c8a5b5174f82b2074dca802f3af8c153
Cr-Commit-Position: refs/heads/master@{#35083}

[Benedikt Meurer, 2016-03-24 13:35:34]

Hey Enrico,

Another builtin.
Please take a look.

Thanks,
 Benedikt

[Benedikt Meurer, 2016-03-27 18:30:23]

Patchset #2 (id:20001) has been deleted

[epertoso, 2016-03-28 09:55:08]

lgtm

https://codereview.chromium.org/1828253002/diff/40001/src/compiler/code-stub-...
File src/compiler/code-stub-assembler.cc (right):

https://codereview.chromium.org/1828253002/diff/40001/src/compiler/code-stub-...
src/compiler/code-stub-assembler.cc:659: { Goto(&if_valueisheapnumber); }
nit: remove the braces for consistency.

https://codereview.chromium.org/1828253002/diff/40001/src/compiler/code-stub-...
File src/compiler/code-stub-assembler.h (right):

https://codereview.chromium.org/1828253002/diff/40001/src/compiler/code-stub-...
src/compiler/code-stub-assembler.h:100: V(Float64ExtractLowWord32)              
  \
Do we really need to expose these two?

[Benedikt Meurer, 2016-03-28 17:00:58]

https://codereview.chromium.org/1828253002/diff/40001/src/compiler/code-stub-...
File src/compiler/code-stub-assembler.cc (right):

https://codereview.chromium.org/1828253002/diff/40001/src/compiler/code-stub-...
src/compiler/code-stub-assembler.cc:659: { Goto(&if_valueisheapnumber); }
On 2016/03/28 09:55:08, epertoso wrote:
> nit: remove the braces for consistency.

Done.

https://codereview.chromium.org/1828253002/diff/40001/src/compiler/code-stub-...
File src/compiler/code-stub-assembler.h (right):

https://codereview.chromium.org/1828253002/diff/40001/src/compiler/code-stub-...
src/compiler/code-stub-assembler.h:100: V(Float64ExtractLowWord32)              
  \
You are right, we don't need to.

[Benedikt Meurer, 2016-03-28 17:05:41]

The CQ bit was checked by bmeurer@chromium.org

[Benedikt Meurer, 2016-03-28 17:05:41]

The patchset sent to the CQ was uploaded after l-g-t-m from
epertoso@chromium.org
Link to the patchset: https://codereview.chromium.org/1828253002/#ps60001
(title: "REBASE. Address feedback.")

[commit-bot: I haz the power, 2016-03-28 17:05:51]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1828253002/60001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1828253002/60001

[commit-bot: I haz the power, 2016-03-28 17:30:14]

Committed patchset #3 (id:60001)

[commit-bot: I haz the power, 2016-03-28 17:31:55]

Description was changed from

==========
[builtins] Provide Math.floor as TurboFan builtin.

This way we avoid the second deoptimization for the Math.floor and
Math.ceil builtins when -0 is involved. We still deoptimize the inlined
Crankshaft version in various cases, that's a separate issue.

The algorithm used for implement CodeStubAssembler::Float64Floor is
vaguely based on the fast math version used in the libm of various BSDs,
but had to be reengineered to match the EcmaScript specification.

R=epertoso@chromium.org
BUG=v8:2890, v8:4059
LOG=n
==========

to

==========
[builtins] Provide Math.floor as TurboFan builtin.

This way we avoid the second deoptimization for the Math.floor and
Math.ceil builtins when -0 is involved. We still deoptimize the inlined
Crankshaft version in various cases, that's a separate issue.

The algorithm used for implement CodeStubAssembler::Float64Floor is
vaguely based on the fast math version used in the libm of various BSDs,
but had to be reengineered to match the EcmaScript specification.

R=epertoso@chromium.org
BUG=v8:2890, v8:4059
LOG=n

Committed: https://crrev.com/36ead519c8a5b5174f82b2074dca802f3af8c153
Cr-Commit-Position: refs/heads/master@{#35083}
==========

[commit-bot: I haz the power, 2016-03-28 17:31:56]

Patchset 3 (id:??) landed as
https://crrev.com/36ead519c8a5b5174f82b2074dca802f3af8c153
Cr-Commit-Position: refs/heads/master@{#35083}