[llvm] [IVDescriptor] Explicitly check for isMinMaxRecurrenceKind in getReductionOpChain. NFC (PR #132025)

[David Sherwood via llvm-commits]

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@@ -1184,15 +1184,15 @@ RecurrenceDescriptor::getReductionOpChain(PHINode *Phi, Loop *L) const {
   // more expensive than out-of-loop reductions, and need to be costed more
   // carefully.
   unsigned ExpectedUses = 1;
-  if (RedOp == Instruction::ICmp || RedOp == Instruction::FCmp)
+  if (isMinMaxRecurrenceKind(Kind))
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david-arm wrote:

Instead of recalculating this each time, is it perhaps better to calculate it once and store it in a variable for reuse?

https://github.com/llvm/llvm-project/pull/132025