DAG: Handle fminnum_ieee/fmaxnum_ieee in basic legalization

Handle these in promote float and vector widening. Currently we happen
to avoid emitting these unless legal or custom. Avoids regression in
a future commit which wants to unconditionally emit these.

Author: arsenm

llvm/lib/CodeGen/SelectionDAG/LegalizeFloatTypes.cpp

@@ -2488,6 +2488,8 @@ void DAGTypeLegalizer::PromoteFloatResult(SDNode *N, unsigned ResNo) {
     case ISD::FMINIMUM:
     case ISD::FMAXNUM:
     case ISD::FMINNUM:
+    case ISD::FMAXNUM_IEEE:
+    case ISD::FMINNUM_IEEE:
     case ISD::FMUL:
     case ISD::FPOW:
     case ISD::FREM:

llvm/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp

@@ -4237,8 +4237,12 @@ void DAGTypeLegalizer::WidenVectorResult(SDNode *N, unsigned ResNo) {
   case ISD::SHL: case ISD::VP_SHL:
   case ISD::SRA: case ISD::VP_SRA:
   case ISD::SRL: case ISD::VP_SRL:
-  case ISD::FMINNUM: case ISD::VP_FMINNUM:
-  case ISD::FMAXNUM: case ISD::VP_FMAXNUM:
+  case ISD::FMINNUM:
+  case ISD::FMINNUM_IEEE:
+  case ISD::VP_FMINNUM:
+  case ISD::FMAXNUM:
+  case ISD::FMAXNUM_IEEE:
+  case ISD::VP_FMAXNUM:
   case ISD::FMINIMUM:
   case ISD::VP_FMINIMUM:
   case ISD::FMAXIMUM: