$OpenBSD: patch-lib_Target_AArch64_AArch64FrameLowering_cpp,v 1.3 2020/09/03 20:54:01 rsadowski Exp $

Add retguard for arm64.

Index: lib/Target/AArch64/AArch64FrameLowering.cpp
--- lib/Target/AArch64/AArch64FrameLowering.cpp.orig
+++ lib/Target/AArch64/AArch64FrameLowering.cpp
@@ -116,6 +116,7 @@
 #include "AArch64InstrInfo.h"
 #include "AArch64MachineFunctionInfo.h"
 #include "AArch64RegisterInfo.h"
+#include "AArch64ReturnProtectorLowering.h"
 #include "AArch64StackOffset.h"
 #include "AArch64Subtarget.h"
 #include "AArch64TargetMachine.h"
@@ -2365,6 +2366,10 @@ void AArch64FrameLowering::determineCalleeSaves(Machin
                                 ? RegInfo->getBaseRegister()
                                 : (unsigned)AArch64::NoRegister;
 
+  if (MFI.hasReturnProtectorRegister() && MFI.getReturnProtectorNeedsStore()) {
+    SavedRegs.set(MFI.getReturnProtectorRegister());
+  }
+
   unsigned ExtraCSSpill = 0;
   // Figure out which callee-saved registers to save/restore.
   for (unsigned i = 0; CSRegs[i]; ++i) {
@@ -2694,4 +2699,8 @@ unsigned AArch64FrameLowering::getWinEHFuncletFrameSiz
   // This is the amount of stack a funclet needs to allocate.
   return alignTo(CSSize + MF.getFrameInfo().getMaxCallFrameSize(),
                  getStackAlignment());
+}
+
+const ReturnProtectorLowering *AArch64FrameLowering::getReturnProtector() const {
+  return &RPL;
 }
