[llvm] [GISel] KnownFPClass ValueTracking fix handling of vectors (PR #143372)

[Matt Arsenault via llvm-commits]

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@@ -715,6 +715,9 @@ static bool outputDenormalIsIEEEOrPosZero(const MachineFunction &MF, LLT Ty) {
 void GISelValueTracking::computeKnownFPClass(Register R, KnownFPClass &Known,
                                              FPClassTest InterestedClasses,
                                              unsigned Depth) {
+  if (!R.isVirtual())
+    return;
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arsenm wrote:

This shouldn't be reached in the first place, this is only relevant for COPY 

https://github.com/llvm/llvm-project/pull/143372