[llvm] [GISel][AArch64] Allow PatLeafs to be imported in GISel which were previously causing warnings (PR #140935)

[via llvm-commits]

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@@ -7985,6 +7996,29 @@ bool AArch64InstructionSelector::isLoadStoreOfNumBytes(
   return (*MI.memoperands_begin())->getSize() == NumBytes;
 }
 
+bool AArch64InstructionSelector::isTop16Zero(const MachineOperand &MO) const {
+  Register Reg = MO.getReg();
+  return VT->maskedValueIsZero(Reg, APInt::getHighBitsSet(32, 16));
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jyli0116 wrote:

>From what I understand from the code, VT is always be available - I could add in a check just to be safe, although I don't think it's super necessary

https://github.com/llvm/llvm-project/pull/140935