Bug 134276 – Provide javascript aware backtrace script for lldb

• Status: RESOLVED
• Resolution: FIXED
• Component: Tools / Tests

[Michael Saboff]

lldb provides the ability to augment lldb functionality via python scripts.  This can be used to make backtraces JavaScript aware.  Consider the backtrace while running deltablue.js from jsc:

(lldb) bt
* thread #1: tid = 0x2c103b, 0x000025c288a61720, queue = 'com.apple.main-thread, stop reason = signal SIGSTOP
    frame #0: 0x000025c288a61720
    frame #1: 0x000025c288a57c40
    frame #2: 0x000025c288a6e050
    frame #3: 0x000025c288a5d654
    frame #4: 0x0000000100647550 JavaScriptCore`llint_entry + 25930
    frame #5: 0x0000000100640d94 JavaScriptCore`callToJavaScript + 356
...

A more informative backtrace could be:
(lldb) bt
* thread \#1: tid = 0x2c103b, 0x000025c288a61720, queue = 'com.apple.main-thread, stop reason = signal SIGSTOP
    frame #0: 0x000025c288a61720 chooseMethod#EmCrCd [DFG](Cell[Object ID: 448]: 0x10994ca70, 97)
    frame #1: 0x000025c288a57c40 satisfy#A7Z1GK [FTL](Cell[Object ID: 448]: 0x10994ca70, 97)
    frame #2: 0x000025c288a6e050 chainTest#BRCzIm [DFG](Cell[global ID: 353]: 0x101cdf970, 100)
    frame #3: 0x000025c288a5d654 deltaBlue#DNE2LT [Baseline](Cell[global ID: 353]: 0x101cdf970)
    frame #4: 0x0000000100647550 <global>#AxbsUM [LLInt](Cell[JSProxy ID: 322]: 0x101cffb90)
    frame #5: 0x0000000100640d94 JavaScriptCore`callToJavaScript + 356
...

[Michael Saboff]

Created attachment 233823 [details]
Patch

[WebKit Commit Bot]

Attachment 233823 [details] did not pass style-queue:


ERROR: Tools/lldb/lldb_webkit.py:101:  expected 2 blank lines, found 1  [pep8/E302] [5]
ERROR: Tools/lldb/lldb_webkit.py:127:  trailing whitespace  [pep8/W291] [5]
Total errors found: 2 in 2 files


If any of these errors are false positives, please file a bug against check-webkit-style.

[Jer Noble]

Comment on attachment 233823 [details]
Patch

nice! r=me.

[Michael Saboff]

Committed r170432: <http://trac.webkit.org/changeset/170432>