993071 - Add JIT-Optimization info to JS profiler

Status: RESOLVED FIXED

(Core :: JavaScript Engine: JIT, defect)

Description

[Kannan Vijayan [:djvj]]

Add JIT optimization info to JS profiler.

To start off, we want the profiler to identify traces which go through slow-paths in the scripts on stack.  The implementation is pretty simple: push pseudostack entries before starting a slowpath, and pop after ending the slowpath.

Comment 1

[Kannan Vijayan [:djvj]]

Attachment: rename-function-boundary-to-profiler-stack-op.patch

Preparatory patch: rename MFunctionBoundary in Ion to MProfilerStackOp.  FunctionBoundary doesn't make sense for annotating slowpaths within functions.

Try run: https://tbpl.mozilla.org/?tree=Try&rev=925abe474e90

Comment 2

[Kannan Vijayan [:djvj]]

Attachment: add-optimization-tier-to-profiler-pseudostack.patch

This patch modifies the usage of the pseudostack to allow js pseudostack entries to indicate if they are for optimized code or not.  It uses the fact that for js entries, the |sp| field is expected to be null.

The patch modifies this to allow |sp| to be either null or (void*)1, where a (void*)1 value indicates that it is for an optimized JS frame.

Try run: https://tbpl.mozilla.org/?tree=Try&rev=439e69c25d2a

Comment 3

[Kannan Vijayan [:djvj]]

Comment on attachment 8403347 [details] [diff] [review]
add-optimization-tier-to-profiler-pseudostack.patch

Canceling review request on this as I just noticed some relevant try failures.

Comment 4

[Kannan Vijayan [:djvj]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/22a4fae1f56a

Comment 5

[Kannan Vijayan [:djvj]]

Attachment: add-optimization-tier-to-profiler-pseudostack.patch

Fixed version of previous patch.  Minor change to sp() method to get this to pass.  Same basic idea.  Copying description from previous patch post:

This patch modifies the usage of the pseudostack to allow js pseudostack entries to indicate if they are for optimized code or not.  It uses the fact that for js entries, the |sp| field is expected to be null.

The patch modifies this to allow |sp| to be either null or (void*)1, where a (void*)1 value indicates that it is for an optimized JS frame.

Now passes try: https://tbpl.mozilla.org/?tree=Try&rev=841f374c2bff

Comment 6

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/mozilla-central/rev/22a4fae1f56a

Comment 7

[Kannan Vijayan [:djvj]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/b7fd2d587e14

Comment 8

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/mozilla-central/rev/b7fd2d587e14

Comment 9

[Till Schneidereit [:till]]

This has long landed.