Bug 165224

Summary: TypeInfo::OutOfLineTypeFlags should be 16 bits in size.
Product: WebKit Reporter: Mark Lam <mark.lam>
Component: JavaScriptCoreAssignee: Mark Lam <mark.lam>
Status: RESOLVED FIXED    
Severity: Normal CC: fpizlo, ggaren, jfbastien, keith_miller, msaboff, saam, ysuzuki
Priority: P2    
Version: WebKit Nightly Build   
Hardware: Unspecified   
OS: Unspecified   
Attachments:
Description Flags
proposed patch. saam: review+

Description Mark Lam 2016-11-30 14:34:51 PST
There's no reason for OutOfLineTypeFlags to be constraint to 8 bits since the space is available to us.  Making OutOfLineTypeFlags 16 bits brings TypeInfo up to 32 bits in size from 24 bits.
Comment 1 Mark Lam 2016-11-30 14:54:56 PST
Created attachment 295774 [details]
proposed patch.
Comment 2 JF Bastien 2016-11-30 15:11:15 PST
Comment on attachment 295774 [details]
proposed patch.

lgtm
Comment 3 Saam Barati 2016-11-30 15:15:44 PST
Comment on attachment 295774 [details]
proposed patch.

Do you have a plan for the extra bits?
Comment 4 Mark Lam 2016-11-30 15:18:33 PST
(In reply to comment #3)
> Comment on attachment 295774 [details]
> proposed patch.
> 
> Do you have a plan for the extra bits?

I have plans to use 1 bit (which would use up the last empty bit in the current 8).  Since I was looking at this code and already did the legwork to confirm that we have the extra space, I wanted to just make it clear in the code that we do have that space should we need to add more bits in the future.
Comment 5 Mark Lam 2016-11-30 16:12:15 PST
Thanks for the reviews.  Landed in r209162: <http://trac.webkit.org/r209162>.