Xcode9b4 - entering comment goes exponential

Originator:markd
Number:rdar://33607955 Date Originated:7/29/2017
Status:Open Resolved:
Product:Developer Tools Product Version:Version 9.0 beta 4 (9M189t)
Classification:Performance Reproducible:Sometimes
 
Summary:
Hi!

I was editing a comment in some swift code, and as I typed, Xcode's responsiveness went away, almost like it was repeatedly processing the line with something exponential.

Attached is the project in question, and a spindump and sample.  I'll be attaching a dropbox link in a subsequent comment.

Seems to be related to editing comments.  Editing code around it is fine.

Steps to Reproduce:
Write Swift code
Start an end of line comment with //
Keep typing

Expected Results:
Editor stays super-responsive and I can type in the comment

Observed Results:
Editor gets.... Slow...er.... w.......i...........t.......h........ e.................. [SPOD]

Version:
Version 9.0 beta 4 (9M189t)
10.12.5 (16F73)

Notes:
I use all-black as my code colorization because of chromatic aberration in my eyeglasses.

Configuration:
Did not occur in Beta3.  I don't recall seeing this in other projects. all UIKit (This particular project is a friend's Cocoa command-line application)
Comments

Comments


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