[wasm] Check for replacements of IndexNodes in the Int64Lowering.

[wasm] Check for replacements of IndexNodes in the Int64Lowering.

The index input of load and store nodes has to be of type int32. However
it is still possible that this index input was lowered by the
Int64Lowering, for example if the index was a kTruncateInt64ToInt32
node. With this CL we check if there exists a replacement of the index
and if so, use the replacement instead of the original index as the
input for the lowered load and store nodes.

BUG=v8:5874
R=titzer@chromium.org, eholk@chromium.org

Review-Url: https://codereview.chromium.org/2644603004
Cr-Commit-Position: refs/heads/master@{#42559}
Committed: https://chromium.googlesource.com/v8/v8/+/fba9047314fabf3f9cd1b68bf67158e544944348

[ahaas, 2017-01-20 12:00:24]

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

[commit-bot: I haz the power, 2017-01-20 12:00:34]

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

[titzer, 2017-01-20 12:01:50]

lgtm

[commit-bot: I haz the power, 2017-01-20 12:05:55]

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

[commit-bot: I haz the power, 2017-01-20 12:05:56]

Dry run: 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...)

[ahaas, 2017-01-20 13:05:50]

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

[commit-bot: I haz the power, 2017-01-20 13:05:57]

Dry run: 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, 2017-01-20 13:37:10]

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

[commit-bot: I haz the power, 2017-01-20 13:37:11]

Dry run: This issue passed the CQ dry run.

[ahaas, 2017-01-20 13:37:25]

The CQ bit was checked by ahaas@chromium.org

[ahaas, 2017-01-20 13:37:25]

The patchset sent to the CQ was uploaded after l-g-t-m from titzer@chromium.org
Link to the patchset: https://codereview.chromium.org/2644603004/#ps20001
(title: "Remove unused variable.")

[commit-bot: I haz the power, 2017-01-20 13:37:30]

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, 2017-01-20 13:39:25]

CQ is committing da patch.

Bot data: {"patchset_id": 20001, "attempt_start_ts": 1484919445283410,
"parent_rev": "77d08c13471829e461db56ee8fc8cf4139ac6f49", "commit_rev":
"fba9047314fabf3f9cd1b68bf67158e544944348"}

[commit-bot: I haz the power, 2017-01-20 13:39:29]

Description was changed from

==========
[wasm] Check for replacements of IndexNodes in the Int64Lowering.

The index input of load and store nodes has to be of type int32. However
it is still possible that this index input was lowered by the
Int64Lowering, for example if the index was a kTruncateInt64ToInt32
node. With this CL we check if there exists a replacement of the index
and if so, use the replacement instead of the original index as the
input for the lowered load and store nodes.

BUG=v8:5874
R=titzer@chromium.org, eholk@chromium.org
==========

to

==========
[wasm] Check for replacements of IndexNodes in the Int64Lowering.

The index input of load and store nodes has to be of type int32. However
it is still possible that this index input was lowered by the
Int64Lowering, for example if the index was a kTruncateInt64ToInt32
node. With this CL we check if there exists a replacement of the index
and if so, use the replacement instead of the original index as the
input for the lowered load and store nodes.

BUG=v8:5874
R=titzer@chromium.org, eholk@chromium.org

Review-Url: https://codereview.chromium.org/2644603004
Cr-Commit-Position: refs/heads/master@{#42559}
Committed:
https://chromium.googlesource.com/v8/v8/+/fba9047314fabf3f9cd1b68bf67158e5449...
==========

[commit-bot: I haz the power, 2017-01-20 13:39:30]

Committed patchset #2 (id:20001) as
https://chromium.googlesource.com/v8/v8/+/fba9047314fabf3f9cd1b68bf67158e5449...