Fix instance compound assignment.

Fix instance compound assignment.

We compiled a.y.x += 1 into a.y.x = a.y.x + 1.
Similarly foo().x++ was compiled into foo().x = foo().x + 1.
Now we store the receiver and reuse it on both sides.

Committed: https://code.google.com/p/dart/source/detail?r=6365

[floitsch, 2012-04-10 12:13:13]

Adding Lasse since Nicolas is on vacation.

[Lasse Reichstein Nielsen, 2012-04-10 12:31:13]

What is the fix (i.e., what wasn't working before). Was there an issue entry?
LGTM.

https://chromiumcodereview.appspot.com/9979021/diff/1/lib/compiler/implementa...
File lib/compiler/implementation/ssa/builder.dart (right):

https://chromiumcodereview.appspot.com/9979021/diff/1/lib/compiler/implementa...
lib/compiler/implementation/ssa/builder.dart:1624: staticInterceptor =
interceptors.getStaticGetInterceptor(getterName);
This pattern seems more complicated than necessary.
Could we just make getStaticGetInterceptor return null if
!methodInterceptionEnabled?
(Not necessarily in this CL)

https://chromiumcodereview.appspot.com/9979021/diff/1/lib/compiler/implementa...
lib/compiler/implementation/ssa/builder.dart:1663:
interceptors.getStaticSetInterceptor(dartSetterName);
Check if this fits on one line. If not, perhaps change "dartSetterName" to
"setterName" to match the getter method above.

https://chromiumcodereview.appspot.com/9979021/diff/1/lib/compiler/implementa...
lib/compiler/implementation/ssa/builder.dart:2215: HInstruction receiver;  //
Only used if the node is an instance send.
Please initialize to null explicitly.

https://chromiumcodereview.appspot.com/9979021/diff/1/lib/compiler/implementa...
lib/compiler/implementation/ssa/builder.dart:2234:
generateInstanceSetterWithCompiledReceiver(node, receiver, operation);
Assert that receiver isn't null here.

https://chromiumcodereview.appspot.com/9979021/diff/1/tests/language/src/Inst...
File tests/language/src/InstanceCompoundAssignmentOperatorTest.dart (right):

https://chromiumcodereview.appspot.com/9979021/diff/1/tests/language/src/Inst...
tests/language/src/InstanceCompoundAssignmentOperatorTest.dart:30: var o = b.a;
How about also counting gets/sets of 'f' (i.e., make a test where 'f' has a
getter and setter that counts too - or just a property g that gets/sets f and
counts).
It's important that we only read b.a once in b.a.f += 1, but also important that
we only read 'f' once and only sets it once.

[floitsch, 2012-04-10 15:51:00]

There was no issue entry. But there was a failing test.

https://chromiumcodereview.appspot.com/9979021/diff/1/lib/compiler/implementa...
File lib/compiler/implementation/ssa/builder.dart (right):

https://chromiumcodereview.appspot.com/9979021/diff/1/lib/compiler/implementa...
lib/compiler/implementation/ssa/builder.dart:1624: staticInterceptor =
interceptors.getStaticGetInterceptor(getterName);
On 2012/04/10 12:31:13, Lasse Reichstein Nielsen wrote:
> This pattern seems more complicated than necessary.
> Could we just make getStaticGetInterceptor return null if
> !methodInterceptionEnabled?
> (Not necessarily in this CL)

This is a copy/paste from below. I will change it in a separate CL.

https://chromiumcodereview.appspot.com/9979021/diff/1/lib/compiler/implementa...
lib/compiler/implementation/ssa/builder.dart:1663:
interceptors.getStaticSetInterceptor(dartSetterName);
On 2012/04/10 12:31:13, Lasse Reichstein Nielsen wrote:
> Check if this fits on one line. If not, perhaps change "dartSetterName" to
> "setterName" to match the getter method above.

Done.

https://chromiumcodereview.appspot.com/9979021/diff/1/lib/compiler/implementa...
lib/compiler/implementation/ssa/builder.dart:2215: HInstruction receiver;  //
Only used if the node is an instance send.
On 2012/04/10 12:31:13, Lasse Reichstein Nielsen wrote:
> Please initialize to null explicitly.

Done.

https://chromiumcodereview.appspot.com/9979021/diff/1/lib/compiler/implementa...
lib/compiler/implementation/ssa/builder.dart:2234:
generateInstanceSetterWithCompiledReceiver(node, receiver, operation);
On 2012/04/10 12:31:13, Lasse Reichstein Nielsen wrote:
> Assert that receiver isn't null here.

Done.

https://chromiumcodereview.appspot.com/9979021/diff/1/tests/language/src/Inst...
File tests/language/src/InstanceCompoundAssignmentOperatorTest.dart (right):

https://chromiumcodereview.appspot.com/9979021/diff/1/tests/language/src/Inst...
tests/language/src/InstanceCompoundAssignmentOperatorTest.dart:30: var o = b.a;
On 2012/04/10 12:31:13, Lasse Reichstein Nielsen wrote:
> How about also counting gets/sets of 'f' (i.e., make a test where 'f' has a
> getter and setter that counts too - or just a property g that gets/sets f and
> counts).
> It's important that we only read b.a once in b.a.f += 1, but also important
that
> we only read 'f' once and only sets it once.

Done.

[ngeoffray, 2012-04-16 15:23:12]

LGTM