RESOLVED FIXED 180804
[DFG] Reduce register pressure of WeakMapGet to be used for 32bit 
https://bugs.webkit.org/show_bug.cgi?id=180804
Summary [DFG] Reduce register pressure of WeakMapGet to be used for 32bit
Yusuke Suzuki
Reported 2017-12-14 03:39:28 PST
[DFG] Reduce register pressure of WeakMapGet to be used for 32bit
Attachments
Patch (5.34 KB, patch)
2017-12-14 03:39 PST, Yusuke Suzuki 		saam: review+
DetailsFormatted DiffDiff
View All Add attachment proposed patch, testcase, etc.
Yusuke Suzuki
Comment 1 2017-12-14 03:39:57 PST
Created attachment 329343 [details] Patch
Yusuke Suzuki
Comment 2 2017-12-14 03:41:06 PST
Comment on attachment 329343 [details] Patch View in context: https://bugs.webkit.org/attachment.cgi?id=329343&action=review > Source/JavaScriptCore/dfg/DFGRegisterBank.h:150 > + } Helper method for debugging.
Saam Barati
Comment 3 2017-12-14 09:49:24 PST
Comment on attachment 329343 [details] Patch View in context: https://bugs.webkit.org/attachment.cgi?id=329343&action=review r=me > Source/JavaScriptCore/dfg/DFGSpeculativeJIT.cpp:10977 > + std::optional<GPRTemporary> index; Why optional? Does GPRTemporary have an empty constructor? If not, maybe it’s worth adding and you can just WTFMove() to it below instead of emplace > Source/JavaScriptCore/dfg/DFGSpeculativeJIT.cpp:10982 > + index.emplace(this, Reuse, hash); Does Reuse only reuse if we’re the last user of the value?
Yusuke Suzuki
Comment 4 2017-12-14 17:38:11 PST
Comment on attachment 329343 [details] Patch View in context: https://bugs.webkit.org/attachment.cgi?id=329343&action=review >> Source/JavaScriptCore/dfg/DFGSpeculativeJIT.cpp:10977 >> + std::optional<GPRTemporary> index; > > Why optional? Does GPRTemporary have an empty constructor? If not, maybe it’s worth adding and you can just WTFMove() to it below instead of emplace OK, changed to using WTFMove(GPRTemporary()). >> Source/JavaScriptCore/dfg/DFGSpeculativeJIT.cpp:10982 >> + index.emplace(this, Reuse, hash); > > Does Reuse only reuse if we’re the last user of the value? Yes, so this Reuse is just an optimization.
Yusuke Suzuki
Comment 5 2017-12-14 17:45:34 PST
Committed r225952: <https://trac.webkit.org/changeset/225952>
Radar WebKit Bug Importer
Comment 6 2017-12-14 17:49:23 PST
<rdar://problem/36064081>
Yusuke Suzuki
Comment 7 2017-12-15 05:59:04 PST
Committed r225971: <https://trac.webkit.org/changeset/225971>
Note You need to log in before you can comment on or make changes to this bug.