[llvm] [AArch64] Sanitise pow inputs using a target DAG combine (PR #192958)

[Paul Walker via llvm-commits]

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@@ -27850,6 +27860,10 @@ static SDValue performVSelectCombine(SDNode *N,
     }
   }
 
+  if ((IfTrue.getOpcode() == ISD::FPOW || IfFalse.getOpcode() == ISD::FPOW))
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paulwalker-arm wrote:

Given all the other `*ValIsPow` checks in `performVselectPowCombine` I think it'll be cleaner to have this check inside as well.

https://github.com/llvm/llvm-project/pull/192958