[PATCH] D15250: Detecte vector reduction operations just before instruction selection.

[Cong Hou via llvm-commits]

congh added a comment.

Ping?


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Comment at: lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp:2410
@@ +2409,3 @@
+        if ((U2->getOperand(0) == U->getOperand(0) && U2->getOperand(1) == U) ||
+            (U2->getOperand(1) == U->getOperand(0) && U2->getOperand(0) == U)) {
+          UsersToVisit.push_back(U2);
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suyog wrote:
> congh wrote:
> > spatel wrote:
> > > For reference, I filed this as PR25808 so I could link it to some other reduction bugs:
> > > https://llvm.org/bugs/show_bug.cgi?id=25808
> > Thanks for filing the bug!
> This may also be related to https://llvm.org/bugs/show_bug.cgi?id=20035
Yes, this is a special case of reduction-on-elements operations.


http://reviews.llvm.org/D15250