[llvm] [AArch64] Mark X16 as clobbered in PAUTH_EPILOGUE for hint-based PAuthLR (PR #175991)

[David Green via llvm-commits]

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@@ -10719,14 +10719,13 @@ void AArch64InstrInfo::fixupPostOutline(MachineBasicBlock &MBB) const {
 static void signOutlinedFunction(MachineFunction &MF, MachineBasicBlock &MBB,
                                  const AArch64InstrInfo *TII,
                                  bool ShouldSignReturnAddr) {
+  assert(&MF.front() == &MBB);
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davemgreen wrote:

Does this need to assert? If so can it add a message to why.

https://github.com/llvm/llvm-project/pull/175991