[llvm] [Intrinsics][AArch64] Add intrinsic to mask off aliasing vector lanes (PR #117007)

[Sam Tebbs via llvm-commits]

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@@ -5201,6 +5215,51 @@ SDValue AArch64TargetLowering::LowerFSINCOS(SDValue Op,
 
 static MVT getSVEContainerType(EVT ContentTy);
 
+SDValue
+AArch64TargetLowering::LowerLOOP_DEPENDENCE_MASK(SDValue Op,
+                                                 SelectionDAG &DAG) const {
+  SDLoc DL(Op);
+  uint64_t EltSize = Op.getConstantOperandVal(2);
+  EVT VT = Op.getValueType();
+  // Make sure that the promoted mask size and element size match
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SamTebbs33 wrote:

I've added widening and splitting support, but I next need to make sure that all of the cases with the assertions are covered, so I can remove the assertions.

https://github.com/llvm/llvm-project/pull/117007