Allow breakpoints on one-liner functions

Allow breakpoints on one-liner functions

Fixes issue 10234. This is also the first step for setting
reliable breakpoints on a == b expressions.

R=srdjan@google.com

Committed: https://code.google.com/p/dart/source/detail?r=22799

[Ivan Posva, 2013-05-16 00:03:52]

DBC -ip

https://codereview.chromium.org/15000005/diff/1/runtime/vm/debugger.cc
File runtime/vm/debugger.cc (right):

https://codereview.chromium.org/15000005/diff/1/runtime/vm/debugger.cc#newcod...
runtime/vm/debugger.cc:1160: if (FLAG_verbose_debug &&
!target_function.HasCode()) {
Check for target_function.HasCode() is confusing as it should not be needed any
longer.

[hausner, 2013-05-16 00:10:46]

https://codereview.chromium.org/15000005/diff/1/runtime/vm/debugger.cc
File runtime/vm/debugger.cc (right):

https://codereview.chromium.org/15000005/diff/1/runtime/vm/debugger.cc#newcod...
runtime/vm/debugger.cc:1160: if (FLAG_verbose_debug &&
!target_function.HasCode()) {
On 2013/05/16 00:03:52, Ivan Posva wrote:
> Check for target_function.HasCode() is confusing as it should not be needed
any
> longer.

Good catch. Also in line 1149. Done.

[srdjan, 2013-05-16 00:11:36]

LGTM

https://codereview.chromium.org/15000005/diff/1/runtime/vm/debugger.cc
File runtime/vm/debugger.cc (right):

https://codereview.chromium.org/15000005/diff/1/runtime/vm/debugger.cc#newcod...
runtime/vm/debugger.cc:863: static bool IsSafePoint(const PcDescriptors&
pc_descs, intptr_t i) {
Optional: I would either move this into the PcDescriptors class or pass in the
Kind only.

https://codereview.chromium.org/15000005/diff/1/runtime/vm/debugger.cc#newcod...
runtime/vm/debugger.cc:1132: DeoptimizeWorld();
Do you need to deoptimize everything (also below)? Could you check if
target_function was maybe not optimized at all?

[hausner, 2013-05-16 15:23:03]

Thank you.

https://codereview.chromium.org/15000005/diff/1/runtime/vm/debugger.cc
File runtime/vm/debugger.cc (right):

https://codereview.chromium.org/15000005/diff/1/runtime/vm/debugger.cc#newcod...
runtime/vm/debugger.cc:863: static bool IsSafePoint(const PcDescriptors&
pc_descs, intptr_t i) {
On 2013/05/16 00:11:36, srdjan wrote:
> Optional: I would either move this into the PcDescriptors class or pass in the
> Kind only.
I would like to keep the debugger-specific stuff local in possible. Changed to
only pass in kind. At one point I thought that I would use more fields of the
descriptor to determine whether it's a safe point. When it gets to that point, I
will make the necessary change.

https://codereview.chromium.org/15000005/diff/1/runtime/vm/debugger.cc#newcod...
runtime/vm/debugger.cc:1132: DeoptimizeWorld();
On 2013/05/16 00:11:36, srdjan wrote:
> Do you need to deoptimize everything (also below)? Could you check if
> target_function was maybe not optimized at all?
See comment at DeoptimizeWorld. Yes, we currently do need to use a big hammer.

[hausner, 2013-05-16 15:44:09]

Committed patchset #2 manually as r22799 (presubmit successful).