Bug 133994

Summary: DFGGraph::m_doubleConstantMap will not map 0 values correctly
Product: WebKit Reporter: Mark Lam <mark.lam>
Component: JavaScriptCoreAssignee: Mark Lam <mark.lam>
Status: RESOLVED FIXED    
Severity: Normal CC: achristensen, commit-queue, fpizlo, ggaren, mhahnenberg, mmirman, msaboff, oliver
Priority: P2    
Version: 528+ (Nightly build)   
Hardware: Unspecified   
OS: Unspecified   
Bug Depends on: 134006    
Bug Blocks:    
Attachments:
Description Flags
the patch.
none
patch 2: fixed build problem, and properly tested on 32-bit build. ggaren: review+

Mark Lam
Reported 2014-06-17 13:09:17 PDT
Filip noticed that m_doubleConstantsMap should not use a double as a key, because it means two unfortunate things: - It will probably break for zero. - It will think that -0 is the same as +0 under some circumstances, size -0==+0 even though they are distinct values (for example 1/-0 != 1/+0). Will fix.
Attachments
the patch. (3.06 KB, patch)
2014-06-17 14:27 PDT, Mark Lam 		no flags
DetailsFormatted DiffDiff
patch 2: fixed build problem, and properly tested on 32-bit build. (2.92 KB, patch)
2014-06-18 08:18 PDT, Mark Lam 		ggaren: review+
DetailsFormatted DiffDiff
Show Obsolete (1) View All Add attachment proposed patch, testcase, etc.
Mark Lam
Comment 1 2014-06-17 14:27:31 PDT
Created attachment 233260 [details] the patch. This patch has passed the JSC tests and the layout tests with a debug build on x86_64.
Alex Christensen
Comment 2 2014-06-17 15:28:43 PDT
Are there ever cases where different NaNs would need to map to the same value?
Geoffrey Garen
Comment 3 2014-06-17 15:39:18 PDT
Comment on attachment 233260 [details] the patch. r=me
Geoffrey Garen
Comment 4 2014-06-17 15:40:11 PDT
(In reply to comment #2) > Are there ever cases where different NaNs would need to map to the same value? In user code, there are only ever two NaNs (positive unsignaling and negative unsignaling), and they do not need (or want) to map to the same value.
WebKit Commit Bot
Comment 5 2014-06-17 16:06:17 PDT
Comment on attachment 233260 [details] the patch. Clearing flags on attachment: 233260 Committed r170082: <http://trac.webkit.org/changeset/170082>
WebKit Commit Bot
Comment 6 2014-06-17 16:06:22 PDT
All reviewed patches have been landed. Closing bug.
WebKit Commit Bot
Comment 7 2014-06-17 16:59:33 PDT
Re-opened since this is blocked by bug 134006
Mark Lam
Comment 8 2014-06-18 08:18:12 PDT
Created attachment 233309 [details] patch 2: fixed build problem, and properly tested on 32-bit build.
Geoffrey Garen
Comment 9 2014-06-18 11:04:42 PDT
Comment on attachment 233309 [details] patch 2: fixed build problem, and properly tested on 32-bit build. r=me
Mark Lam
Comment 10 2014-06-18 11:58:32 PDT
Thanks. Landed in r170109: <http://trac.webkit.org/r170109>.
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