Bug 164390

Summary: REGRESSION (r208349) StringHasher::hashMemory behavior changed, causing API tests to fail
Product: WebKit Reporter: Brady Eidson <beidson>
Component: Web Template FrameworkAssignee: Brady Eidson <beidson>
Status: RESOLVED FIXED    
Severity: Normal CC: commit-queue, darin, ggaren, ryanhaddad
Priority: P2    
Version: WebKit Nightly Build   
Hardware: Unspecified   
OS: Unspecified   
Attachments:
Description Flags
Patch none

Brady Eidson
Reported 2016-11-03 17:10:16 PDT
REGRESSION (r208349) StringHasher::hashMemory behavior changed, causing API tests to fail Link to the change: https://trac.webkit.org/changeset/208349 The difference is that memory hashing used to mask the top 8 bits of the hash, just like string hashing needed. Now it no longer does. We can either restore the masking behavior, or accept the change in behavior (as an improvement, I think) and update the test. Note: There was a FIXME in hashMemory that called out how odd it was that we masked the top 8 bits for memory hashing when it wasn't needed like for string hashing.
Attachments
Patch (2.78 KB, patch)
2016-11-03 17:12 PDT, Brady Eidson 		no flags
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Brady Eidson
Comment 1 2016-11-03 17:12:52 PDT
Created attachment 293830 [details] Patch
Geoffrey Garen
Comment 2 2016-11-04 10:41:03 PDT
Comment on attachment 293830 [details] Patch Specifically, we don't see any reason that memory hashing needs to mask off the high bits of the hash code, even though string hashing does so in order to support an implementation of StringImpl that stores flags in the high bits of the hash code.
WebKit Commit Bot
Comment 3 2016-11-04 11:05:31 PDT
Comment on attachment 293830 [details] Patch Clearing flags on attachment: 293830 Committed r208387: <http://trac.webkit.org/changeset/208387>
WebKit Commit Bot
Comment 4 2016-11-04 11:05:35 PDT
All reviewed patches have been landed. Closing bug.
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