From 769ced3d576bef1098c1e5819d4afeb9eee4d6bd Mon Sep 17 00:00:00 2001
From: Tim Northover <t.p.northover@gmail.com>
Date: Mon, 17 May 2021 11:34:16 +0100
Subject: [PATCH] AArch64: mark x22 livein if it's an async context that gets
 stored.

This fixes a crash with expensive checks enabled (the verifier was not happy).
---
 llvm/lib/Target/AArch64/AArch64FrameLowering.cpp | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/llvm/lib/Target/AArch64/AArch64FrameLowering.cpp b/llvm/lib/Target/AArch64/AArch64FrameLowering.cpp
index 64ad462..7ef3007 100644
--- a/llvm/lib/Target/AArch64/AArch64FrameLowering.cpp
+++ b/llvm/lib/Target/AArch64/AArch64FrameLowering.cpp
@@ -1270,7 +1270,8 @@ void AArch64FrameLowering::emitPrologue(MachineFunction &MF,
       // record, so store it now.
       const auto &Attrs = MF.getFunction().getAttributes();
       bool HaveInitialContext = Attrs.hasAttrSomewhere(Attribute::SwiftAsync);
-
+      if (HaveInitialContext)
+        MBB.addLiveIn(AArch64::X22);
       BuildMI(MBB, MBBI, DL, TII->get(AArch64::StoreSwiftAsyncContext))
           .addUse(HaveInitialContext ? AArch64::X22 : AArch64::XZR)
           .addUse(AArch64::SP)
-- 
2.7.4