Compute out arguments size

Compute the size of the stack space required to send the parameters to a call.

BUG=
R=jpp@chromium.org

Committed: https://gerrit.chromium.org/gerrit/gitweb?p=native_client/pnacl-subzero.git;a=commit;h=4163b9fcd92c0e2604a0d5f52ad1eccc86cad266

[sehr, 2015-11-20 23:22:52]

Description was changed from

==========
Allocate out arguments in the prolog

BUG=
==========

to

==========
Compute the size of the stack space required to send the parameters to a call.

BUG=
==========

[sehr, 2015-11-21 00:35:25]

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

[sehr, 2015-11-21 00:36:16]

First version for x86.  PTAL.

[John, 2015-11-21 01:03:28]

lgtm

[sehr, 2015-11-21 05:09:35]

Committed patchset #5 (id:80001) manually as
4163b9fcd92c0e2604a0d5f52ad1eccc86cad266 (presubmit successful).

[Jim Stichnoth, 2015-11-22 04:12:16]

lgtm

https://codereview.chromium.org/1458713002/diff/80001/src/IceTargetLoweringX8...
File src/IceTargetLoweringX86BaseImpl.h (right):

https://codereview.chromium.org/1458713002/diff/80001/src/IceTargetLoweringX8...
src/IceTargetLoweringX86BaseImpl.h:5360: if
(isScalarFloatingType(Dest->getType())) {
use DestType instead of Dest->getType()