[turbofan] Use appropriate type for NodeId.

[turbofan] Use appropriate type for NodeId.

Up until now we used int32_t for NodeId, but that was not ideal because
negative values are invalid for NodeId and we use it as an array index
for example in the NodeMarker class, where C++ compilers on x64 have to
generate code that does proper sign extension for the indices, which is
completely unnecessary.

R=svenpanne@chromium.org

Committed: https://crrev.com/c487aba74c1898e6f54a00001d84e30b39261d96
Cr-Commit-Position: refs/heads/master@{#28997}

[Benedikt Meurer, 2015-06-12 08:37:07]

Hey Sven,

This is an obvious one. Please take a look.

Thanks,
Benedikt

[Sven Panne, 2015-06-12 11:19:36]

https://codereview.chromium.org/1178403004/diff/20001/src/compiler/simplified...
File src/compiler/simplified-lowering.cc (right):

https://codereview.chromium.org/1178403004/diff/20001/src/compiler/simplified...
src/compiler/simplified-lowering.cc:75:
info_(zone->NewArray<NodeInfo>(static_cast<int>(count_))),
AFAICT, we don't need the static_cast here. By design (accident? ;-) the types
fit...

[Sven Panne, 2015-06-12 11:26:55]

LGTM if my nit is addressed, BTW :-)

[Benedikt Meurer, 2015-06-12 11:28:02]

The CQ bit was checked by bmeurer@chromium.org

[Benedikt Meurer, 2015-06-12 11:28:02]

The patchset sent to the CQ was uploaded after l-g-t-m from
svenpanne@chromium.org
Link to the patchset: https://codereview.chromium.org/1178403004/#ps30016
(title: "Fix useless static_cast.")

[commit-bot: I haz the power, 2015-06-12 11:28:11]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1178403004/30016

[commit-bot: I haz the power, 2015-06-12 12:03:08]

Committed patchset #4 (id:30016)

[commit-bot: I haz the power, 2015-06-12 12:03:29]

Patchset 4 (id:??) landed as
https://crrev.com/c487aba74c1898e6f54a00001d84e30b39261d96
Cr-Commit-Position: refs/heads/master@{#28997}