Reland r21101: "ARM64: use jssp for stack slots"

Reland r21101: "ARM64: use jssp for stack slots"

The original implementation assumed that LPushArguments and
LInvoke/Call* could be assumed to be exclusively sequential. However,
this isn't always the case. For example, GenerateCallFunction pushes
some arguments and then selects between HInvokeFunction and
HCallFunction.

This fixed implementation resets a pushed_arguments_ counter based on
the argument_count() of the preceeding basic block, then tracks it
per-instruction as before (except that now we maintain a count rather
than a boolean flag).

At the same time, since we now track exactly how many arguments have
been pushed onto the stack, I was able to adjust the offset accordingly
and use jssp for stack slots even when arguments have been pushed.

BUG=

Committed: https://crrev.com/48d726cd6f6ad176d54b546b7d1ca717e5478b46
Cr-Commit-Position: refs/heads/master@{#29249}

[jbramley, 2015-03-27 10:46:16]

jacob.bramley@arm.com changed reviewers:
+ bmeurer@chromium.org, ulan@chromium.org, verwaest@google.com

[jbramley, 2015-05-29 12:35:21]

Could someone have a look please?

[Benedikt Meurer, 2015-06-24 06:20:13]

bmeurer@chromium.org changed reviewers:
+ verwaest@chromium.org
- verwaest@google.com

[Benedikt Meurer, 2015-06-24 06:20:15]

LGTM. Sorry for the delay.

[Benedikt Meurer, 2015-06-24 06:20:18]

The CQ bit was checked by bmeurer@chromium.org

[commit-bot: I haz the power, 2015-06-24 06:20:26]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1038363002/20001

[commit-bot: I haz the power, 2015-06-24 06:20:27]

The author jacob.bramley@arm.com has not signed Google Contributor License
Agreement. Please visit https://cla.developers.google.com to sign and manage
CLA.

[commit-bot: I haz the power, 2015-06-24 06:30:42]

The author jacob.bramley@arm.com has not signed Google Contributor License
Agreement. Please visit https://cla.developers.google.com to sign and manage
CLA.

[commit-bot: I haz the power, 2015-06-24 06:47:32]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-06-24 06:47:54]

Patchset 2 (id:??) landed as
https://crrev.com/48d726cd6f6ad176d54b546b7d1ca717e5478b46
Cr-Commit-Position: refs/heads/master@{#29249}