[llvm] [GISel] matchFPSelect to use FMINMAX IEEE variant (PR #123774)

[Matt Arsenault via llvm-commits]

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@@ -6442,27 +6442,27 @@ unsigned CombinerHelper::getFPMinMaxOpcForSelect(
   case CmpInst::FCMP_OGT:
   case CmpInst::FCMP_OGE:
     if (VsNaNRetVal == SelectPatternNaNBehaviour::RETURNS_OTHER)
-      return TargetOpcode::G_FMAXNUM;
+      return TargetOpcode::G_FMAXNUM_IEEE;
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arsenm wrote:

These are not freely interchangeable opcodes. SelectPatternNaNBehaviour does not cover the snan behavior

https://github.com/llvm/llvm-project/pull/123774