pull MarkFlagResult out from between an EmitNode/CompleteMatch
pair. This encourages MorphNodeTo formation, this gets us 200
more MorphNodeTo's on X86 and shrinks the table a bit.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97434 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/utils/TableGen/DAGISelMatcherOpt.cpp b/utils/TableGen/DAGISelMatcherOpt.cpp
index f8dfe6d..5fe21f6 100644
--- a/utils/TableGen/DAGISelMatcherOpt.cpp
+++ b/utils/TableGen/DAGISelMatcherOpt.cpp
@@ -67,7 +67,23 @@
return ContractNodes(MatcherPtr, CGP);
}
- // FIXME: Handle OPC_MarkFlagResults.
+ // Turn EmitNode->MarkFlagResults->CompleteMatch into
+ // MarkFlagResults->EmitNode->CompleteMatch when we can to encourage
+ // MorphNodeTo formation. This is safe because MarkFlagResults never refers
+ // to the root of the pattern.
+ if (isa<EmitNodeMatcher>(N) && isa<MarkFlagResultsMatcher>(N->getNext()) &&
+ isa<CompleteMatchMatcher>(N->getNext()->getNext())) {
+ // Unlink the two nodes from the list.
+ Matcher *EmitNode = MatcherPtr.take();
+ Matcher *MFR = EmitNode->takeNext();
+ Matcher *Tail = MFR->takeNext();
+
+ // Relink them.
+ MatcherPtr.reset(MFR);
+ MFR->setNext(EmitNode);
+ EmitNode->setNext(Tail);
+ return ContractNodes(MatcherPtr, CGP);
+ }
// Turn EmitNode->CompleteMatch into MorphNodeTo if we can.
if (EmitNodeMatcher *EN = dyn_cast<EmitNodeMatcher>(N))