Bug 150454

Summary: Air needs to know which subset of an argument an operation will use or def
Product: WebKit Reporter: Filip Pizlo <fpizlo>
Component: JavaScriptCoreAssignee: Nobody <webkit-unassigned>
Status: RESOLVED FIXED    
Severity: Normal    
Priority: P2    
Version: WebKit Nightly Build   
Hardware: All   
OS: All   
Bug Depends on:    
Bug Blocks: 150279    

Description Filip Pizlo 2015-10-22 11:02:03 PDT 
That would allow us to spill it more compactly and emit tighter code in general.

It would also be cool if Def32 could be made to clearly imply that the high bits are zero'd, since that would allow us to eliminate more zero extensions from the code.
Comment 1 Filip Pizlo 2016-01-26 21:58:57 PST 
We fixed this already.