[llvm] [GlobalISel] [AArch64] Skip redundant shift amount masking during isel (PR #223136)

[David Green via llvm-commits]

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@@ -7302,6 +7306,51 @@ AArch64InstructionSelector::selectShiftB_64(const MachineOperand &Root) const {
   return {{[=](MachineInstrBuilder &MIB) { MIB.addImm(Enc); }}};
 }
 
+InstructionSelector::ComplexRendererFns
+AArch64InstructionSelector::selectShiftMask(MachineOperand &Root,
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davemgreen wrote:

Make ShiftWidth a template parameter?

https://github.com/llvm/llvm-project/pull/223136