[debugger] account for inlined functions when stepping.

[debugger] account for inlined functions when stepping.

- Remove obsolete BreakLocatorType.
- Perform PrepareStepOnThrow after OnException event, in case stepping
  was scheduled in the exception event.
- Use frame count instead of frame pointer for stepping. Frame pointer
  is not reliable due to possible deopts.
- Consistently check for inlined functions in inlined frames.
- Use SharedFunctionInfo in FloodWithOneshot and EnsureDebugInfo.

R=jgruber@chromium.org
BUG=v8:5901
Review-Url: https://codereview.chromium.org/2664793002
Cr-Commit-Position: refs/heads/master@{#42878}
Committed: https://chromium.googlesource.com/v8/v8/+/d9399cc36be0e5dc2ded0ca664864c05391d8cf8

[jgruber, 2017-01-30 15:42:17]

Nice cleanup, lgtm.

And nit: formatting on the commit message seems off.

https://codereview.chromium.org/2664793002/diff/1/src/debug/debug.cc
File src/debug/debug.cc (left):

https://codereview.chromium.org/2664793002/diff/1/src/debug/debug.cc#oldcode191
src/debug/debug.cc:191: if (isolate()->is_tail_call_elimination_enabled()) {
Is TCE now enabled by default? Or why is this now unconditional?

https://codereview.chromium.org/2664793002/diff/1/src/debug/debug.h
File src/debug/debug.h (right):

https://codereview.chromium.org/2664793002/diff/1/src/debug/debug.h#newcode354
src/debug/debug.h:354: // if a valid closure is passed as the second argument,
otherwise the shared
Comment seems outdated.

https://codereview.chromium.org/2664793002/diff/1/test/debugger/regress/regre...
File test/debugger/regress/regress-5901-2.js (right):

https://codereview.chromium.org/2664793002/diff/1/test/debugger/regress/regre...
test/debugger/regress/regress-5901-2.js:42: h();
So just to be clear, h() is optimized at this point, and is deoptimized later?
When hitting 'debugger' or when after triggering the first listener call?

[Yang, 2017-01-30 19:47:19]

https://codereview.chromium.org/2664793002/diff/1/src/debug/debug.cc
File src/debug/debug.cc (left):

https://codereview.chromium.org/2664793002/diff/1/src/debug/debug.cc#oldcode191
src/debug/debug.cc:191: if (isolate()->is_tail_call_elimination_enabled()) {
On 2017/01/30 15:42:17, jgruber wrote:
> Is TCE now enabled by default? Or why is this now unconditional?

If TCE is not enabled, the emitted code will not have any reloc info marked with
DEBUG_BREAK_SLOT_AT_TAIL_CALL. Adding it to the mode mask would not hurt. This
is just a simplification.

https://codereview.chromium.org/2664793002/diff/1/test/debugger/regress/regre...
File test/debugger/regress/regress-5901-2.js (right):

https://codereview.chromium.org/2664793002/diff/1/test/debugger/regress/regre...
test/debugger/regress/regress-5901-2.js:42: h();
On 2017/01/30 15:42:17, jgruber wrote:
> So just to be clear, h() is optimized at this point, and is deoptimized later?
> When hitting 'debugger' or when after triggering the first listener call?

h is optimized at this point, and it inlines g and f. It will be deoptimized
when we step out from f, thereby setting break points in g.
PrepareFunctionForBreakpoint will iterate the heap to find all functions that
inline g. So h will be deoptimized.

[Yang, 2017-01-31 11:34:06]

Description was changed from

==========
[debugger] account for inlined functions when stepping.

- Remove obsolete BreakLocatorType.
- Perform PrepareStepOnThrow after OnException event, in case stepping
  was scheduled in the exception event.
- Use frame count instead of frame pointer for stepping. Frame pointer
  is not reliable due to possible deopts.
- Consistently check for inlined functions in inlined frames.
- Use SharedFunctionInfo in FloodWithOneshot and EnsureDebugInfo.

[debugger] consider optimized frames for stepping.


.


.


.


.

R=jgruber@chromium.org
BUG=
==========

to

==========
[debugger] account for inlined functions when stepping.

- Remove obsolete BreakLocatorType.
- Perform PrepareStepOnThrow after OnException event, in case stepping
  was scheduled in the exception event.
- Use frame count instead of frame pointer for stepping. Frame pointer
  is not reliable due to possible deopts.
- Consistently check for inlined functions in inlined frames.
- Use SharedFunctionInfo in FloodWithOneshot and EnsureDebugInfo.

R=jgruber@chromium.org
BUG=v8:5901
==========

[Yang, 2017-01-31 11:34:12]

The CQ bit was checked by yangguo@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2017-01-31 11:34:15]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-01-31 11:35:45]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2017-01-31 11:35:46]

Dry run: Try jobs failed on following builders:
  v8_linux64_asan_rel_ng on master.tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux64_asan_rel_ng/buil...)
  v8_linux64_avx2_rel_ng on master.tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux64_avx2_rel_ng/buil...)
  v8_linux64_gyp_rel_ng on master.tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux64_gyp_rel_ng/build...)
  v8_linux64_rel_ng on master.tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux64_rel_ng/builds/20178)
  v8_linux_arm64_rel_ng on master.tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux_arm64_rel_ng/build...)
  v8_linux_arm_rel_ng on master.tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux_arm_rel_ng/builds/...)
  v8_linux_mipsel_compile_rel on master.tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux_mipsel_compile_rel...)
  v8_linux_nodcheck_rel_ng on master.tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux_nodcheck_rel_ng/bu...)
  v8_presubmit on master.tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_presubmit/builds/33700)
  v8_win_rel_ng on master.tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_win_rel_ng/builds/21889)

[Yang, 2017-02-02 07:02:09]

The CQ bit was checked by yangguo@chromium.org

[Yang, 2017-02-02 07:02:10]

The patchset sent to the CQ was uploaded after l-g-t-m from jgruber@chromium.org
Link to the patchset: https://codereview.chromium.org/2664793002/#ps40001
(title: "comment addressed")

[commit-bot: I haz the power, 2017-02-02 07:02:13]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-02-02 07:31:10]

CQ is committing da patch.

Bot data: {"patchset_id": 40001, "attempt_start_ts": 1486018929823360,
"parent_rev": "9432eb5c6aab2b8e74c01a8a2f79e690eb94b3e2", "commit_rev":
"d9399cc36be0e5dc2ded0ca664864c05391d8cf8"}

[commit-bot: I haz the power, 2017-02-02 07:31:14]

Description was changed from

==========
[debugger] account for inlined functions when stepping.

- Remove obsolete BreakLocatorType.
- Perform PrepareStepOnThrow after OnException event, in case stepping
  was scheduled in the exception event.
- Use frame count instead of frame pointer for stepping. Frame pointer
  is not reliable due to possible deopts.
- Consistently check for inlined functions in inlined frames.
- Use SharedFunctionInfo in FloodWithOneshot and EnsureDebugInfo.

R=jgruber@chromium.org
BUG=v8:5901
==========

to

==========
[debugger] account for inlined functions when stepping.

- Remove obsolete BreakLocatorType.
- Perform PrepareStepOnThrow after OnException event, in case stepping
  was scheduled in the exception event.
- Use frame count instead of frame pointer for stepping. Frame pointer
  is not reliable due to possible deopts.
- Consistently check for inlined functions in inlined frames.
- Use SharedFunctionInfo in FloodWithOneshot and EnsureDebugInfo.

R=jgruber@chromium.org
BUG=v8:5901

Review-Url: https://codereview.chromium.org/2664793002
Cr-Commit-Position: refs/heads/master@{#42878}
Committed:
https://chromium.googlesource.com/v8/v8/+/d9399cc36be0e5dc2ded0ca664864c05391...
==========

[commit-bot: I haz the power, 2017-02-02 07:31:15]

Committed patchset #3 (id:40001) as
https://chromium.googlesource.com/v8/v8/+/d9399cc36be0e5dc2ded0ca664864c05391...