[llvm] DAG: Fix chain mismanagement in SoftenFloatRes_FP_EXTEND (PR #74406)

[Matt Arsenault via llvm-commits]

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@@ -2276,6 +2298,26 @@ SDValue DAGTypeLegalizer::PromoteFloatOp_FP_EXTEND(SDNode *N, unsigned OpNo) {
   return DAG.getNode(ISD::FP_EXTEND, SDLoc(N), VT, Op);
 }
 
+SDValue DAGTypeLegalizer::PromoteFloatOp_STRICT_FP_EXTEND(SDNode *N,
+                                                          unsigned OpNo) {
+  assert(OpNo == 1);
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arsenm wrote:

This is also from the parent commit, this PR is supposed to just be the top one

https://github.com/llvm/llvm-project/pull/74406