PPC/s390: [turbofan] Remove special JSForInStep and JSForInDone.

PPC/s390: [turbofan] Remove special JSForInStep and JSForInDone.

Port 1915762cc8caea42727daebfe738bfcdca8ac859

Original commit message:

    These JavaScript operators were special hacks to ensure that we always
    operate on Smis for the magic for-in index variable, but this never
    really worked in the OSR case, because the OsrValue for the index
    variable didn't have the proper information (that we have for the
    JSForInPrepare in the non-OSR case).

    Now that we have loop induction variable analysis and binary operation
    hints, we can just use JSLessThan and JSAdd instead with appropriate
    Smi hints, which handle the OSR case by inserting Smi checks (that are
    always true). Thanks to OSR deconstruction and loop peeling these Smi
    checks will be hoisted so they don't hurt the OSR case too much.

    Drive-by-change: Rename the ForInDone bytecode to ForInContinue, since
    we have to lower it to JSLessThan to get the loop induction variable
    goodness.

R=bmeurer@chromium.org, joransiu@ca.ibm.com, jyan@ca.ibm.com, michael_dawson@ca.ibm.com
BUG=
LOG=N

Committed: https://crrev.com/b4ccb16a979eca94be735691d736287b3715f736
Cr-Commit-Position: refs/heads/master@{#40947}

[JaideepBajwa, 2016-11-14 02:51:27]

ptal

[john.yan, 2016-11-14 02:52:46]

lgtm

[JaideepBajwa, 2016-11-14 02:53:15]

The CQ bit was checked by bjaideep@ca.ibm.com

[commit-bot: I haz the power, 2016-11-14 02:53:17]

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, 2016-11-14 03:18:37]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-11-17 22:31:44]

Description was changed from

==========
PPC/s390: [turbofan] Remove special JSForInStep and JSForInDone.

Port 1915762cc8caea42727daebfe738bfcdca8ac859

Original commit message:

    These JavaScript operators were special hacks to ensure that we always
    operate on Smis for the magic for-in index variable, but this never
    really worked in the OSR case, because the OsrValue for the index
    variable didn't have the proper information (that we have for the
    JSForInPrepare in the non-OSR case).

    Now that we have loop induction variable analysis and binary operation
    hints, we can just use JSLessThan and JSAdd instead with appropriate
    Smi hints, which handle the OSR case by inserting Smi checks (that are
    always true). Thanks to OSR deconstruction and loop peeling these Smi
    checks will be hoisted so they don't hurt the OSR case too much.

    Drive-by-change: Rename the ForInDone bytecode to ForInContinue, since
    we have to lower it to JSLessThan to get the loop induction variable
    goodness.

R=bmeurer@chromium.org, joransiu@ca.ibm.com, jyan@ca.ibm.com,
michael_dawson@ca.ibm.com
BUG=
LOG=N
==========

to

==========
PPC/s390: [turbofan] Remove special JSForInStep and JSForInDone.

Port 1915762cc8caea42727daebfe738bfcdca8ac859

Original commit message:

    These JavaScript operators were special hacks to ensure that we always
    operate on Smis for the magic for-in index variable, but this never
    really worked in the OSR case, because the OsrValue for the index
    variable didn't have the proper information (that we have for the
    JSForInPrepare in the non-OSR case).

    Now that we have loop induction variable analysis and binary operation
    hints, we can just use JSLessThan and JSAdd instead with appropriate
    Smi hints, which handle the OSR case by inserting Smi checks (that are
    always true). Thanks to OSR deconstruction and loop peeling these Smi
    checks will be hoisted so they don't hurt the OSR case too much.

    Drive-by-change: Rename the ForInDone bytecode to ForInContinue, since
    we have to lower it to JSLessThan to get the loop induction variable
    goodness.

R=bmeurer@chromium.org, joransiu@ca.ibm.com, jyan@ca.ibm.com,
michael_dawson@ca.ibm.com
BUG=
LOG=N

Committed: https://crrev.com/b4ccb16a979eca94be735691d736287b3715f736
Cr-Commit-Position: refs/heads/master@{#40947}
==========

[commit-bot: I haz the power, 2016-11-17 22:31:45]

Patchset 1 (id:??) landed as
https://crrev.com/b4ccb16a979eca94be735691d736287b3715f736
Cr-Commit-Position: refs/heads/master@{#40947}