Compute default throws behavior from JavaScript.

Compute default throwing behavior from JavaScript.

This change removes the heuristic that 'general effects imply may-throw behavior', replacing it with explicit throwing behavior.

A new JavaScript AST visitor provides the default throwing behavior.

R=floitsch@google.com

Committed: https://code.google.com/p/dart/source/detail?r=45070

[sra1, 2015-04-10 02:46:47]

Patchset #1 (id:1) has been deleted

[sra1, 2015-04-10 02:46:54]

Patchset #1 (id:20001) has been deleted

[sra1, 2015-04-10 02:59:21]

sra@google.com changed reviewers:
+ floitsch@google.com

[floitsch, 2015-04-10 13:34:16]

LGTM.

https://codereview.chromium.org/1074043003/diff/40001/pkg/compiler/lib/src/na...
File pkg/compiler/lib/src/native/js.dart (right):

https://codereview.chromium.org/1074043003/diff/40001/pkg/compiler/lib/src/na...
pkg/compiler/lib/src/native/js.dart:91: /// operators are used on 'good'
operands thatdo not force arbirary code to be
that do

https://codereview.chromium.org/1074043003/diff/40001/pkg/compiler/lib/src/na...
pkg/compiler/lib/src/native/js.dart:106: static NativeThrowBehavior
sequence(NativeThrowBehavior first,
Add comment explaining what this is.
(probably my fault, but I started reading it as "visitSequence")

https://codereview.chromium.org/1074043003/diff/40001/pkg/compiler/lib/src/na...
pkg/compiler/lib/src/native/js.dart:165: // TODO(sra): `new Array(x)` where `x`
is is a small number.
-is-

https://codereview.chromium.org/1074043003/diff/40001/pkg/compiler/lib/src/na...
pkg/compiler/lib/src/native/js.dart:231: // fragments, the only use of
VariableUse should be for gloabl references.
global

https://codereview.chromium.org/1074043003/diff/40001/pkg/compiler/lib/src/na...
pkg/compiler/lib/src/native/js.dart:235: case 'Array':
add
case 'Object':

[sra1, 2015-04-10 15:57:49]

https://chromiumcodereview.appspot.com/1074043003/diff/40001/pkg/compiler/lib...
File pkg/compiler/lib/src/native/js.dart (right):

https://chromiumcodereview.appspot.com/1074043003/diff/40001/pkg/compiler/lib...
pkg/compiler/lib/src/native/js.dart:91: /// operators are used on 'good'
operands thatdo not force arbirary code to be
On 2015/04/10 13:34:16, floitsch wrote:
> that do

Done.

https://chromiumcodereview.appspot.com/1074043003/diff/40001/pkg/compiler/lib...
pkg/compiler/lib/src/native/js.dart:106: static NativeThrowBehavior
sequence(NativeThrowBehavior first,
On 2015/04/10 13:34:16, floitsch wrote:
> Add comment explaining what this is.
> (probably my fault, but I started reading it as "visitSequence")

Done.

https://chromiumcodereview.appspot.com/1074043003/diff/40001/pkg/compiler/lib...
pkg/compiler/lib/src/native/js.dart:165: // TODO(sra): `new Array(x)` where `x`
is is a small number.
On 2015/04/10 13:34:16, floitsch wrote:
> -is-

Done.

https://chromiumcodereview.appspot.com/1074043003/diff/40001/pkg/compiler/lib...
pkg/compiler/lib/src/native/js.dart:231: // fragments, the only use of
VariableUse should be for gloabl references.
On 2015/04/10 13:34:16, floitsch wrote:
> global

Done.

https://chromiumcodereview.appspot.com/1074043003/diff/40001/pkg/compiler/lib...
pkg/compiler/lib/src/native/js.dart:235: case 'Array':
On 2015/04/10 13:34:16, floitsch wrote:
> add
> case 'Object':

Done, but it is not really useful, since most uses of Object are sufficiently
compound to have MAY-throw behavior (e.g. Object.keys(#) is a property access
and call.)

Array is here because of  #.$fixedLength = Array.

[sra1, 2015-04-10 16:00:14]

Committed patchset #2 (id:60001) manually as 45070 (presubmit successful).