diff --git a/llvm/include/llvm/CodeGen/MachineBasicBlock.h b/llvm/include/llvm/CodeGen/MachineBasicBlock.h
--- a/llvm/include/llvm/CodeGen/MachineBasicBlock.h
+++ b/llvm/include/llvm/CodeGen/MachineBasicBlock.h
@@ -896,13 +896,19 @@
   /// Convenience function that returns true if the block ends in a return
   /// instruction.
   bool isReturnBlock() const {
-    return !empty() && back().isReturn();
+    for (auto &I : terminators())
+      if (I.isReturn())
+        return true;
+    return false;
   }
 
   /// Convenience function that returns true if the bock ends in a EH scope
   /// return instruction.
   bool isEHScopeReturnBlock() const {
-    return !empty() && back().isEHScopeReturn();
+    for (auto &I : terminators())
+      if (I.isEHScopeReturn())
+        return true;
+    return false;
   }
 
   /// Split a basic block into 2 pieces at \p SplitPoint. A new block will be
diff --git a/llvm/test/CodeGen/AArch64/sls-stackprotector-outliner.ll b/llvm/test/CodeGen/AArch64/sls-stackprotector-outliner.ll
--- a/llvm/test/CodeGen/AArch64/sls-stackprotector-outliner.ll
+++ b/llvm/test/CodeGen/AArch64/sls-stackprotector-outliner.ll
@@ -1,8 +1,9 @@
 ; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 2
 ; RUN: llc < %s | FileCheck %s
 
-; Test case to demonstrate a bug where calls to OUTLINED_FUNCTION_1 are
-; inserted at a point where LR is live.
+; Previously, we did not track the liveness of LR around SLS-protected tail
+; calls, so the outliner could insert a BL just before one, clobbering the LR
+; value it uses.
 
 target datalayout = "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128"
 target triple = "aarch64-arm-none-eabi"
@@ -18,7 +19,8 @@
 ; CHECK-NEXT:    b.ne .LBB0_2
 ; CHECK-NEXT:  // %bb.1: // %entry
 ; CHECK-NEXT:    ldr x30, [sp, #16] // 8-byte Folded Reload
-; CHECK-NEXT:    bl OUTLINED_FUNCTION_1
+; CHECK-NEXT:    add x0, x0, x8
+; CHECK-NEXT:    add sp, sp, #32
 ; CHECK-NEXT:    b _ZN2C6D1Ev
 ; CHECK-NEXT:    dsb sy
 ; CHECK-NEXT:    isb
@@ -45,7 +47,8 @@
 ; CHECK-NEXT:    b.ne .LBB1_2
 ; CHECK-NEXT:  // %bb.1: // %entry
 ; CHECK-NEXT:    ldr x30, [sp, #16] // 8-byte Folded Reload
-; CHECK-NEXT:    bl OUTLINED_FUNCTION_1
+; CHECK-NEXT:    add x0, x0, x8
+; CHECK-NEXT:    add sp, sp, #32
 ; CHECK-NEXT:    b _ZN2C6D0Ev
 ; CHECK-NEXT:    dsb sy
 ; CHECK-NEXT:    isb
@@ -71,7 +74,8 @@
 ; CHECK-NEXT:    b.ne .LBB2_2
 ; CHECK-NEXT:  // %bb.1: // %entry
 ; CHECK-NEXT:    ldr x30, [sp, #16] // 8-byte Folded Reload
-; CHECK-NEXT:    bl OUTLINED_FUNCTION_1
+; CHECK-NEXT:    add x0, x0, x8
+; CHECK-NEXT:    add sp, sp, #32
 ; CHECK-NEXT:    b _ZN3C10D1Ev
 ; CHECK-NEXT:    dsb sy
 ; CHECK-NEXT:    isb
@@ -97,7 +101,8 @@
 ; CHECK-NEXT:    b.ne .LBB3_2
 ; CHECK-NEXT:  // %bb.1: // %entry
 ; CHECK-NEXT:    ldr x30, [sp, #16] // 8-byte Folded Reload
-; CHECK-NEXT:    bl OUTLINED_FUNCTION_1
+; CHECK-NEXT:    add x0, x0, x8
+; CHECK-NEXT:    add sp, sp, #32
 ; CHECK-NEXT:    b _ZN3C10D0Ev
 ; CHECK-NEXT:    dsb sy
 ; CHECK-NEXT:    isb