Bug 147950

Summary: DFG::ByteCodeParser should attempt constant folding on loads from structures that are DFG-watchable
Product: WebKit Reporter: Filip Pizlo <fpizlo>
Component: JavaScriptCoreAssignee: Filip Pizlo <fpizlo>
Status: RESOLVED FIXED    
Severity: Normal    
Priority: P2    
Version: 528+ (Nightly build)   
Hardware: All   
OS: All   
Attachments:
Description Flags
the patch msaboff: review+

Description Filip Pizlo 2015-08-12 13:31:29 PDT 
We accidentally broke the ByteCodeParser's constant folding of loads from constants with DFG-watchable structures in http://trac.webkit.org/changeset/188292.  The constant folding would happen later, but there are some constant folding rules that only the ByteCodeParser is capable of, particularly with things like CreateThis.
Comment 1 Filip Pizlo 2015-08-12 13:38:50 PDT 
Created attachment 258842 [details]
the patch
Comment 2 Michael Saboff 2015-08-12 13:41:00 PDT 
Comment on attachment 258842 [details]
the patch

r=me
Comment 3 Filip Pizlo 2015-08-12 14:02:04 PDT 
Landed in http://trac.webkit.org/changeset/188357