1382076 - Make DMD usable on Win32

Status: RESOLVED FIXED

(Core :: DMD, enhancement)

Description

[Nicholas Nethercote [inactive]]

DMD has been unusable on Win32 for a long time because it makes Firefox astonishingly slow to start-up, for complex reasons explained in bug 1241684.

The solution is that same as the solution for Mac in bug 1371397: change DMD so it uses FramePointerStackWalk() instead of MozStackWalk() on Win32. This is what the Gecko Profiler does, and it works well.

Comment 1

[Nicholas Nethercote [inactive]]

(In case it wasn't clear: DMD already works fine on Win64.)

Comment 2

[Nicholas Nethercote [inactive]]

Attachment: Use FramePointerStackWalk() in DMD on Win32

The patch also uses a better value for skipFrames on Win64.

Comment 3

[Eric Rahm [:erahm]]

Comment on attachment 8887743 [details] [diff] [review]
Use FramePointerStackWalk() in DMD on Win32

Review of attachment 8887743 [details] [diff] [review]:
-----------------------------------------------------------------

r+ with the mentioned fix.

::: memory/replace/dmd/DMD.cpp
@@ +814,1 @@
>      bool ok = MozStackWalk(StackWalkCallback, /* skipFrames = */ 2,

Presumably this should be changed to |, skipFrames,|

Comment 4

[Nicholas Nethercote [inactive]]

> Presumably this should be changed to |, skipFrames,|

Yikes! Good catch. I retested after fixing this and it turns out that 1 is a better value for Win64.

Comment 5

[Nicholas Nethercote [inactive]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/8b89d684f633977acdd317654d040a86ddef466b
Bug 1382076 - Use FramePointerStackWalk() in DMD on Win32. r=erahm.

Comment 6

[Sebastian Hengst [:aryx] (needinfo me if it's about an intermittent or backout)]

https://hg.mozilla.org/mozilla-central/rev/8b89d684f633