Fix base register for stack variables in ARM integrated assembler.

Fix base register for stack variables in ARM integrated assembler.

When translating an Variable without a register, the code assumes the
variable is on the stack using sp. This is still true. However, if it
is a (derived class) StackVariable, the register defined by
getBaseRegNum() should be used instead.

BUG= https://code.google.com/p/nativeclient/issues/detail?id=4334
R=jpp@chromium.org, stichnot@chromium.org

Committed: https://gerrit.chromium.org/gerrit/gitweb?p=native_client/pnacl-subzero.git;a=commit;h=57586f731ecfd18527434b5256f991bdf2e80192

[Karl, 2015-11-03 22:26:08]

Description was changed from

==========
Fix base register for stack variables in ARM integrated assembler.

When translating an Variable without a register, the code assumes the
variable is on the stack using sp. This is still true. However, if it
is a (derived class) StackVariable, the register defined by
getBaseRegNum() should be used instead.

BUG= https://code.google.com/p/nativeclient/issues/detail?id=4334
==========

to

==========
Fix base register for stack variables in ARM integrated assembler.

When translating an Variable without a register, the code assumes the
variable is on the stack using sp. This is still true. However, if it
is a (derived class) StackVariable, the register defined by
getBaseRegNum() should be used instead.

BUG= https://code.google.com/p/nativeclient/issues/detail?id=4334
==========

[Karl, 2015-11-03 22:26:08]

kschimpf@google.com changed reviewers:
+ jpp@chromium.org, sehr@chromium.org, stichnot@chromium.org

[John, 2015-11-03 23:47:51]

lgtm

[Jim Stichnoth, 2015-11-04 01:04:09]

LGTM.

If this fixes any of the broken instructions worked around in the other CL, I
would go ahead and land this first and remove the exceptions from the other CL.

[Karl, 2015-11-04 16:10:48]

Committed patchset #3 (id:40001) manually as
57586f731ecfd18527434b5256f991bdf2e80192 (presubmit successful).

[Karl, 2015-11-04 16:11:42]

Unfortunately, this was an independent bug that did not break cross tests, but
is unrelated to the instructions that aren't working.