[llvm] [ValueTracking][KnownFPClass] Cover known no-infinity cases for powi (PR #191736)

[Yingwei Zheng via llvm-commits]

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@@ -1379,18 +1379,30 @@ void GISelValueTracking::computeKnownFPClass(Register R,
     break;
   }
   case TargetOpcode::G_FPOWI: {
-    if ((InterestedClasses & fcNegative) == fcNone)
+    if ((InterestedClasses & (fcNan | fcInf | fcNegative)) == fcNone)
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dtcxzyw wrote:

Please add some tests to llvm/unittests/CodeGen/GlobalISel/KnownFPClassTest.cpp.


https://github.com/llvm/llvm-project/pull/191736