[llvm] [AArch64] Stop reserved registers from being saved in prolog/epilog (PR #138448)

[Eli Friedman via llvm-commits]

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@@ -551,6 +563,11 @@ bool AArch64RegisterInfo::isReservedReg(const MachineFunction &MF,
   return getReservedRegs(MF)[Reg];
 }
 
+bool AArch64RegisterInfo::isUserReservedReg(const MachineFunction &MF,
+                                            MCRegister Reg) const {
+  return getUserReservedRegs(MF)[Reg];
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efriedma-quic wrote:

I guess given the actual number of GPRs on AArch64 is a fixed number, it's not a big deal to loop 1000 times.

https://github.com/llvm/llvm-project/pull/138448