Fix a VM bug in the handling of try/catch/finally.

Fix a VM bug in the handling of try/catch/finally.

In the case that code in the catch block threw in any fashion, the
finally block was not executed.  Fix this by properly treating the
finally block of try/catch/finally as an exception handler for the
catch block.

R=fschneider@google.com, srdjan@google.com
BUG=https://code.google.com/p/dart/issues/detail?id=430

Committed: https://code.google.com/p/dart/source/detail?r=24583

[Kevin Millikin (Google), 2013-06-26 14:27:04]

https://codereview.chromium.org/17893003/diff/1/runtime/vm/flow_graph_builder.cc
File runtime/vm/flow_graph_builder.cc (left):

https://codereview.chromium.org/17893003/diff/1/runtime/vm/flow_graph_builder...
runtime/vm/flow_graph_builder.cc:3247: intptr_t old_try_index =
owner()->try_index();
The name 'try_index' isn't quite right.  There can be more than one handler per
try (i.e., a catch and a finally) so numbering each try doesn't serve to
identify the handler.

I propose changing the name to 'handler_index', but I'd make that as a separate,
cosmetic-only, change.

[Florian Schneider, 2013-06-27 14:05:59]

LGTM.

[cc +vm-dev]

https://codereview.chromium.org/17893003/diff/1/runtime/vm/flow_graph_builder.cc
File runtime/vm/flow_graph_builder.cc (right):

https://codereview.chromium.org/17893003/diff/1/runtime/vm/flow_graph_builder...
runtime/vm/flow_graph_builder.cc:3338: if ((node->finally_block() != NULL) &&
is_open()) {
s/node->finally_block()/finally_block/

https://codereview.chromium.org/17893003/diff/1/runtime/vm/flow_graph_builder...
runtime/vm/flow_graph_builder.cc:3340:
node->finally_block()->Visit(&for_finally_block);
s/node->finally_block()/finally_block/

[srdjan, 2013-06-27 22:42:33]

LGTM

[Kevin Millikin (Google), 2013-06-28 11:59:08]

https://codereview.chromium.org/17893003/diff/1/runtime/vm/flow_graph_builder.cc
File runtime/vm/flow_graph_builder.cc (right):

https://codereview.chromium.org/17893003/diff/1/runtime/vm/flow_graph_builder...
runtime/vm/flow_graph_builder.cc:3338: if ((node->finally_block() != NULL) &&
is_open()) {
On 2013/06/27 14:05:59, Florian Schneider wrote:
> s/node->finally_block()/finally_block/

Well spotted.  Done.

[Kevin Millikin (Google), 2013-06-28 12:29:05]

Committed patchset #1 manually as r24583 (presubmit successful).