Reapply changes reverted by r343235

- Add fix so that all code paths that create DWARFContext
  with an ObjectFile initialise the target architecture in the context
- Add an assert that the Arch is known in the Dwarf CallFrameString method

llvm-svn: 343317

1 files changed, 6 insertions, 0 deletions

diff --git a/llvm/lib/Target/AArch64/AArch64FrameLowering.cpp b/llvm/lib/Target/AArch64/AArch64FrameLowering.cpp
index f2d7ea9ba3e..2e377127302 100644
--- a/llvm/lib/Target/AArch64/AArch64FrameLowering.cpp
+++ b/llvm/lib/Target/AArch64/AArch64FrameLowering.cpp
@@ -622,6 +622,12 @@ void AArch64FrameLowering::emitPrologue(MachineFunction &MF,
   if (ShouldSignReturnAddress(MF)) {
     BuildMI(MBB, MBBI, DL, TII->get(AArch64::PACIASP))
         .setMIFlag(MachineInstr::FrameSetup);
+
+    unsigned CFIIndex =
+        MF.addFrameInst(MCCFIInstruction::createNegateRAState(nullptr));
+    BuildMI(MBB, MBBI, DL, TII->get(TargetOpcode::CFI_INSTRUCTION))
+        .addCFIIndex(CFIIndex)
+        .setMIFlags(MachineInstr::FrameSetup);
   }
 
   // All calls are tail calls in GHC calling conv, and functions have no