[llvm] [SelectionDAG] Remove `UnsafeFPMath` in LegalizeDAG (PR #146316)

[Matt Arsenault via llvm-commits]

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@@ -3853,7 +3853,7 @@ bool SelectionDAGLegalize::ExpandNode(SDNode *Node) {
     break;
   case ISD::FP_TO_FP16:
     LLVM_DEBUG(dbgs() << "Legalizing FP_TO_FP16\n");
-    if (!TLI.useSoftFloat() && TM.Options.UnsafeFPMath) {
+    if (!TLI.useSoftFloat() && Node->getFlags().hasApproximateFuncs()) {
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arsenm wrote:

These checks should be swapped 

https://github.com/llvm/llvm-project/pull/146316