Don't assume we want the iOS ABI if running simarm on Mac and the EABI otherwise.

Don't assume we want the iOS ABI if running simarm on Mac and the EABI otherwise.

Allow controlling the target ABI by defining TARGET_ABI_IOS or TARGET_ABI_EABI.  If neither is defined, default to the previous behavior.

Make Linux, Mac, Android and iOS agree on the value of PreferredCodeAlignment for all architectures.

BUG=http://dartbug.com/26464
R=zra@google.com

Committed: https://github.com/dart-lang/sdk/commit/85cdc0eac20e823c827d65685da8b1a9e1d9c2fe

[rmacnak, 2016-05-16 21:53:43]

Description was changed from

==========
Don't assume we want the iOS ABI if running simarm on Mac and the EABI
otherwise.
==========

to

==========
Don't assume we want the iOS ABI if running simarm on Mac and the EABI
otherwise.

Allow controlling the target ABI by defining TARGET_ABI_IOS or TARGET_ABI_EABI. 
If neither is defined, default to the previous behavior.

BUG=http://dartbug.com/26464
==========

[rmacnak, 2016-05-17 01:37:37]

Description was changed from

==========
Don't assume we want the iOS ABI if running simarm on Mac and the EABI
otherwise.

Allow controlling the target ABI by defining TARGET_ABI_IOS or TARGET_ABI_EABI. 
If neither is defined, default to the previous behavior.

BUG=http://dartbug.com/26464
==========

to

==========
Don't assume we want the iOS ABI if running simarm on Mac and the EABI
otherwise.

Allow controlling the target ABI by defining TARGET_ABI_IOS or TARGET_ABI_EABI. 
If neither is defined, default to the previous behavior.

Make Linux, Mac, Android and iOS agree on the value of PreferredCodeAlignment
for all architectures.

BUG=http://dartbug.com/26464
==========

[rmacnak, 2016-05-17 01:45:17]

rmacnak@google.com changed reviewers:
+ fschneider@google.com, vegorov@google.com, zra@google.com

[rmacnak, 2016-05-17 01:45:17]

Not thrilled about the code alignment part. The issue is we're currently using
the value of the host OS instead of the target OS.

[Florian Schneider, 2016-05-17 12:44:53]

Does that mean I have to rebuild gen_snapshot / dart_bootstrap when I switch
between generating iOS or Android snapshots on my Macbook? Ideally, the target
ABI should be configurable via the command-line for snapshot generation.

[zra, 2016-05-17 15:37:25]

On 2016/05/17 12:44:53, Florian Schneider wrote:
> Does that mean I have to rebuild gen_snapshot / dart_bootstrap when I switch
> between generating iOS or Android snapshots on my Macbook? Ideally, the target
> ABI should be configurable via the command-line for snapshot generation.

I would tend to agree with Florian. It looks like several of the constants in
constants_*.h and stack_frame_*.h, and the arch agnostic register aliases in
constants_*.h would have to be refactored into functions that check a flag.
Maybe making a function in stack_frame_*.h could at least be avoided by
preserving another register in the iOS ABI to eliminate the difference in stack
frame size? But I think it's okay if this all happens in a different CL.

OTOH, it seems like now is also a good time to summarize the differences between
the ABIs at the top of constants_arm.h.

[rmacnak, 2016-05-17 21:21:50]

Added some ABI description. PTAL.

[rmacnak, 2016-05-17 21:32:50]

On 2016/05/17 12:44:53, Florian Schneider wrote:
> Does that mean I have to rebuild gen_snapshot / dart_bootstrap when I switch
> between generating iOS or Android snapshots on my Macbook? Ideally, the target
> ABI should be configurable via the command-line for snapshot generation.

Currently yes.  Making all the relevant values in constants_arm.h to depend on a
runtime flag is a bigger change.

[zra, 2016-05-17 21:35:45]

lgtm

[rmacnak, 2016-05-17 22:04:00]

Description was changed from

==========
Don't assume we want the iOS ABI if running simarm on Mac and the EABI
otherwise.

Allow controlling the target ABI by defining TARGET_ABI_IOS or TARGET_ABI_EABI. 
If neither is defined, default to the previous behavior.

Make Linux, Mac, Android and iOS agree on the value of PreferredCodeAlignment
for all architectures.

BUG=http://dartbug.com/26464
==========

to

==========
Don't assume we want the iOS ABI if running simarm on Mac and the EABI
otherwise.

Allow controlling the target ABI by defining TARGET_ABI_IOS or TARGET_ABI_EABI. 
If neither is defined, default to the previous behavior.

Make Linux, Mac, Android and iOS agree on the value of PreferredCodeAlignment
for all architectures.

BUG=http://dartbug.com/26464
R=zra@google.com

Committed:
https://github.com/dart-lang/sdk/commit/85cdc0eac20e823c827d65685da8b1a9e1d9c2fe
==========

[rmacnak, 2016-05-17 22:04:02]

Committed patchset #4 (id:60001) manually as
85cdc0eac20e823c827d65685da8b1a9e1d9c2fe (presubmit successful).

[Florian Schneider, 2016-05-18 07:21:14]

On 2016/05/17 21:32:50, rmacnak wrote:
> On 2016/05/17 12:44:53, Florian Schneider wrote:
> > Does that mean I have to rebuild gen_snapshot / dart_bootstrap when I switch
> > between generating iOS or Android snapshots on my Macbook? Ideally, the
target
> > ABI should be configurable via the command-line for snapshot generation.
> 
> Currently yes.  Making all the relevant values in constants_arm.h to depend on
a
> runtime flag is a bigger change.

Lgtm. Ok, sounds good to me for now. We may want to add a gyp-define variable as
well... Or does
the GN build work for the standalone VM?

[rmacnak, 2016-05-18 17:37:40]

On 2016/05/18 07:21:14, Florian Schneider wrote:
> On 2016/05/17 21:32:50, rmacnak wrote:
> > On 2016/05/17 12:44:53, Florian Schneider wrote:
> > > Does that mean I have to rebuild gen_snapshot / dart_bootstrap when I
switch
> > > between generating iOS or Android snapshots on my Macbook? Ideally, the
> target
> > > ABI should be configurable via the command-line for snapshot generation.
> > 
> > Currently yes.  Making all the relevant values in constants_arm.h to depend
on
> a
> > runtime flag is a bigger change.
> 
> Lgtm. Ok, sounds good to me for now. We may want to add a gyp-define variable
as
> well... Or does
> the GN build work for the standalone VM?

I believe we currently still cannot build the standalone VM from GN. If neither
define is provided, we default to EABI on Linux and iOS on Mac, so the mac
precompilation bots are still testing the iOS path.