[llvm] [ConstantFPRange] Implement `ConstantFPRange::makeAllowedFCmpRegion` (PR #110082)

[Matt Arsenault via llvm-commits]

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@@ -117,9 +221,10 @@ ConstantFPRange::makeSatisfyingFCmpRegion(FCmpInst::Predicate Pred,
   return getEmpty(Other.getSemantics());
 }
 
-ConstantFPRange ConstantFPRange::makeExactFCmpRegion(FCmpInst::Predicate Pred,
-                                                     const APFloat &Other) {
-  return makeAllowedFCmpRegion(Pred, ConstantFPRange(Other));
+std::optional<ConstantFPRange>
+ConstantFPRange::makeExactFCmpRegion(FCmpInst::Predicate Pred,
+                                     const APFloat &Other) {
+  return std::nullopt;
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arsenm wrote:

This is changed but still does nothing? 

https://github.com/llvm/llvm-project/pull/110082