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Change-Id: Ia4b65e49c9007ae6b13a10ce2ea8ee1411036dc0

Author: MacDue

llvm/lib/Target/AArch64/MachineSMEABIPass.cpp

@@ -219,6 +219,9 @@ struct MachineSMEABI : public MachineFunctionPass {
   void emitSetupFullZASave(MachineBasicBlock &MBB,
                            MachineBasicBlock::iterator MBBI,
                            LiveRegs PhysLiveRegs);
+  // Emit a "full" ZA save or restore. It is "full" in the sense that this
+  // function will emit a call to __arm_sme_save or __arm_sme_restore, which
+  // handles saving and restoring both ZA and ZT0.
   void emitFullZASaveRestore(MachineBasicBlock &MBB,
                              MachineBasicBlock::iterator MBBI,
                              LiveRegs PhysLiveRegs, bool IsSave);