725067 - IonMonkey: Crash [@ js::gc::ChunkBitmap::markIfUnmarked]

Status: RESOLVED FIXED

(Core :: JavaScript Engine, defect)

Description

[Christian Holler (:decoder)]

The following testcase crashes on ionmonkey revision d66c148e0756 (run with --ion -n), tested on 64 bit:


var o0 = [];
var o4 = {};
var o5 = Math;
function f6(o) { o[("Keywords")] = o;};
for(var i=0; i<20; i++) {
    f6(o0);
    f6(o4);
    f6(o5);
}
gc();

Comment 1

[David Anderson [:dvander] - inactive, e-mail if emergency]

The bug here is that lhs == rhs in the register allocator, and then we generate code like:

   push lhs
   mov [lhs.slots], lhs
   mov rhs, [lhs]
   pop lhs

So we just need to get an extra register. But before that I'd like to refactor the SetProperty stuff so it looks more like GetProperty/GetElement.

Comment 2

[David Anderson [:dvander] - inactive, e-mail if emergency]

Attachment: part 1: split MGenericSetProperty up

This patch splits MGenericSetProperty into MCallSetProperty and MSetPropertyCache. LCallSetPropertyV/T are then combined into one unspecialized LCallSetProperty.

Comment 3

[David Anderson [:dvander] - inactive, e-mail if emergency]

Attachment: part 2, rename LCacheSetProperty to LSetPropertyCache

Comment 4

[David Anderson [:dvander] - inactive, e-mail if emergency]

Attachment: part 3, fix the bug

Comment 6

[Jan de Mooij [:jandem]]

Comment on attachment 595519 [details] [diff] [review]
part 1: split MGenericSetProperty up

Review of attachment 595519 [details] [diff] [review]:
-----------------------------------------------------------------

::: js/src/ion/MIR.h
@@ +2959,5 @@
>      bool strict_;
> +
> +  protected:
> +    MSetPropertyInstruction(MDefinition *obj, MDefinition *value, JSAtom *atom,
> +                        bool strict)

Nit: this needs some extra spaces

Comment 7

[Jan de Mooij [:jandem]]

Comment on attachment 595521 [details] [diff] [review]
part 2, rename LCacheSetProperty to LSetPropertyCache

Review of attachment 595521 [details] [diff] [review]:
-----------------------------------------------------------------

What about renaming GetPropertyCache so these instructions use either a Call* or a Cache* prefix?

Comment 8

[David Anderson [:dvander] - inactive, e-mail if emergency]

http://hg.mozilla.org/projects/ionmonkey/rev/9cd94217ee4f
http://hg.mozilla.org/projects/ionmonkey/rev/d546f1b141b9
http://hg.mozilla.org/projects/ionmonkey/rev/28c66941856b

I think I prefer Call/Cache as suffixes, but it's not a strong preference.

Comment 9

[Christian Holler (:decoder)]

A testcase for this bug was automatically identified at js/src/jit-test/tests/ion/bug725067.js.