[mips] implement enough bytecodes to run hello.dart

[mips] implement enough bytecodes to run hello.dart

With this change, MIPS Dartino can run hello.dart from samples/general/.

Also, this change incorporates some ARM changes from

> More compact snapshots
> https://codereview.chromium.org/2067483002/

Patch by RT-RK.

BUG= https://github.com/dartino/sdk/issues/496
TEST= ninja -C out/DebugXMIPS

Committed: https://github.com/dartino/sdk/commit/7b3fd93c207a3238a8213732f4d80d910d1bb8e9

[petarj, 2016-06-23 17:12:40]

Description was changed from

==========
[mips] implement enough bytecodes to run hello.dart

With this change, MIPS Dartino can run hello.dart from samples/general/.

Also, this change incorporates some ARM changes from

> More compact snapshots
> https://codereview.chromium.org/2067483002/

Patch by RT-RK.

BUG= https://github.com/dartino/sdk/issues/496
TEST= ninja -C out/DebugXMIPS
==========

to

==========
[mips] implement enough bytecodes to run hello.dart

With this change, MIPS Dartino can run hello.dart from samples/general/.

Also, this change incorporates some ARM changes from

> More compact snapshots
> https://codereview.chromium.org/2067483002/

Patch by RT-RK.

BUG= https://github.com/dartino/sdk/issues/496
TEST= ninja -C out/DebugXMIPS
==========

[petarj, 2016-06-23 17:12:40]

petarj@mips.com changed reviewers:
+ erik.corry@gmail.com, sgjesse@google.com

[petarj, 2016-06-23 17:14:25]

petarj@mips.com changed reviewers:
+ erikcorry@google.com
- erik.corry@gmail.com

[petarj, 2016-06-23 17:18:49]

New patch uploaded. PTAL.

[erikcorry, 2016-06-27 15:51:08]

https://codereview.chromium.org/2088133005/diff/1/src/vm/interpreter_mips.cc
File src/vm/interpreter_mips.cc (right):

https://codereview.chromium.org/2088133005/diff/1/src/vm/interpreter_mips.cc#...
src/vm/interpreter_mips.cc:810: Dispatch(kInvokeAddLength);
kInvokeSubLength

https://codereview.chromium.org/2088133005/diff/1/src/vm/interpreter_mips.cc#...
src/vm/interpreter_mips.cc:898: __ li(T0, Immediate(31));
Perhaps save one instruction with

sra(T0, A1, Immediate(5));
bne(T0, ZR, fallback);

https://codereview.chromium.org/2088133005/diff/1/src/vm/interpreter_mips.cc#...
src/vm/interpreter_mips.cc:1255: // Fetch the virtual table from the program.
Comment is out of date.

https://codereview.chromium.org/2088133005/diff/1/src/vm/interpreter_mips.cc#...
src/vm/interpreter_mips.cc:1610: __ B(cond, reg1, reg2, &add);
Optimization idea for a later CL: If the condition is LT or GT and the add_if_eq
is a power of 2, then this can be done with SLT and shift with no branches.

If the condition is EQ then you can do it with two SLTs and an OR.

[petarj, 2016-06-29 02:09:15]

New patch uploaded. PTAL.

https://codereview.chromium.org/2088133005/diff/1/src/vm/interpreter_mips.cc
File src/vm/interpreter_mips.cc (right):

https://codereview.chromium.org/2088133005/diff/1/src/vm/interpreter_mips.cc#...
src/vm/interpreter_mips.cc:810: Dispatch(kInvokeAddLength);
On 2016/06/27 15:51:08, erikcorry wrote:
> kInvokeSubLength

Done.

https://codereview.chromium.org/2088133005/diff/1/src/vm/interpreter_mips.cc#...
src/vm/interpreter_mips.cc:898: __ li(T0, Immediate(31));
On 2016/06/27 15:51:08, erikcorry wrote:
> Perhaps save one instruction with
> 
> sra(T0, A1, Immediate(5));
> bne(T0, ZR, fallback);

Done, thanks for the idea.

https://codereview.chromium.org/2088133005/diff/1/src/vm/interpreter_mips.cc#...
src/vm/interpreter_mips.cc:1255: // Fetch the virtual table from the program.
On 2016/06/27 15:51:08, erikcorry wrote:
> Comment is out of date.

Removed.

https://codereview.chromium.org/2088133005/diff/1/src/vm/interpreter_mips.cc#...
src/vm/interpreter_mips.cc:1610: __ B(cond, reg1, reg2, &add);
On 2016/06/27 15:51:08, erikcorry wrote:
> Optimization idea for a later CL: If the condition is LT or GT and the
add_if_eq
> is a power of 2, then this can be done with SLT and shift with no branches.
> 
> If the condition is EQ then you can do it with two SLTs and an OR.

Thanks, will use in one of the later CLs.

[erikcorry, 2016-06-29 09:04:46]

Description was changed from

==========
[mips] implement enough bytecodes to run hello.dart

With this change, MIPS Dartino can run hello.dart from samples/general/.

Also, this change incorporates some ARM changes from

> More compact snapshots
> https://codereview.chromium.org/2067483002/

Patch by RT-RK.

BUG= https://github.com/dartino/sdk/issues/496
TEST= ninja -C out/DebugXMIPS
==========

to

==========
[mips] implement enough bytecodes to run hello.dart

With this change, MIPS Dartino can run hello.dart from samples/general/.

Also, this change incorporates some ARM changes from

> More compact snapshots
> https://codereview.chromium.org/2067483002/

Patch by RT-RK.

BUG= https://github.com/dartino/sdk/issues/496
TEST= ninja -C out/DebugXMIPS

Committed:
https://github.com/dartino/sdk/commit/7b3fd93c207a3238a8213732f4d80d910d1bb8e9
==========

[erikcorry, 2016-06-29 09:04:48]

Committed patchset #2 (id:20001) manually as
7b3fd93c207a3238a8213732f4d80d910d1bb8e9 (presubmit successful).

[erikcorry, 2016-06-29 09:04:57]

lgtm