Bug 69291 - DFG backends don't have access to per-node predictions from the propagator
Summary: DFG backends don't have access to per-node predictions from the propagator
Status: RESOLVED FIXED
Alias: None
Product: WebKit
Classification: Unclassified
Component: JavaScriptCore (show other bugs)
Version: 528+ (Nightly build)
Hardware: All All
: P2 Normal
Assignee: Nobody
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2011-10-03 13:50 PDT by Filip Pizlo
Modified: 2011-10-03 18:05 PDT (History)
0 users

See Also:

Attachments
the patch (19.63 KB, patch)
2011-10-03 14:01 PDT, Filip Pizlo 		oliver: review+
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Description Filip Pizlo 2011-10-03 13:50:46 PDT 
The DFG propagator has complete knowledge of how each node in the data flow graph is predicted.  But this knowledge is lost when going to the backend.  The backends try to reinfer this, but do so poorly (for example the backend has no idea how to predict a ConvertThis node, while the propagator knows exactly how to predict it).
Comment 1 Filip Pizlo 2011-10-03 14:01:46 PDT 
Created attachment 109527 [details]
the patch
Comment 2 Oliver Hunt 2011-10-03 17:35:12 PDT 
Comment on attachment 109527 [details]
the patch

r=me
Comment 3 Filip Pizlo 2011-10-03 18:05:26 PDT 
Landed in r96562.