[llvm] [AArch64] Add vector expansion support for ISD::FCBRT when using ArmPL (PR #183750)

[Matt Arsenault via llvm-commits]

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@@ -19358,7 +19361,10 @@ SDValue DAGCombiner::visitFPOW(SDNode *N) {
 
     // Do not create a cbrt() libcall if the target does not have it, and do not
     // turn a pow that has lowering support into a cbrt() libcall.
-    if (!DAG.getLibInfo().has(LibFunc_cbrt) ||
+    RTLIB::Libcall LC = RTLIB::getCBRT(VT);
+    bool HasLibCall =
+        DAG.getTargetLoweringInfo().getLibcallImpl(LC) != RTLIB::Unsupported;
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arsenm wrote:

Don't use the libcall lowering info from TargetLowering, use it from the DAG 

https://github.com/llvm/llvm-project/pull/183750