diff --git a/llvm/lib/MC/MCWin64EH.cpp b/llvm/lib/MC/MCWin64EH.cpp
--- a/llvm/lib/MC/MCWin64EH.cpp
+++ b/llvm/lib/MC/MCWin64EH.cpp
@@ -614,24 +614,33 @@
   const std::vector<WinEH::Instruction> &Epilog =
       info->EpilogMap.begin()->second;
 
+  // Check that the epilog actually is at the very end of the function,
+  // otherwise it can't be packed.
+  uint32_t DistanceFromEnd = (uint32_t)GetAbsDifference(
+      streamer, info->FuncletOrFuncEnd, info->EpilogMap.begin()->first);
+  if (DistanceFromEnd / 4 != Epilog.size())
+    return -1;
+
+  int RetVal = -1;
+  // Even if we don't end up sharing opcodes with the prolog, we can still
+  // write the offset as a packed offset, if the single epilog is located at
+  // the end of the function and the offset (pointing after the prolog) fits
+  // as a packed offset.
+  if (PrologCodeBytes <= 31 &&
+      PrologCodeBytes + ARM64CountOfUnwindCodes(Epilog) <= 124)
+    RetVal = PrologCodeBytes;
+
   // Can pack if the epilog is a subset of the prolog but not vice versa
   if (Epilog.size() > info->Instructions.size())
-    return -1;
+    return RetVal;
 
   // Check that the epilog actually is a perfect match for the end (backwrds)
   // of the prolog.
   for (int I = Epilog.size() - 1; I >= 0; I--) {
     if (info->Instructions[I] != Epilog[Epilog.size() - 1 - I])
-      return -1;
+      return RetVal;
   }
 
-  // Check that the epilog actually is at the very end of the function,
-  // otherwise it can't be packed.
-  uint32_t DistanceFromEnd = (uint32_t)GetAbsDifference(
-      streamer, info->FuncletOrFuncEnd, info->EpilogMap.begin()->first);
-  if (DistanceFromEnd / 4 != Epilog.size())
-    return -1;
-
   int Offset = Epilog.size() == info->Instructions.size()
                    ? 0
                    : ARM64CountOfUnwindCodes(ArrayRef<WinEH::Instruction>(
@@ -642,8 +651,10 @@
   // unclear whether the epilog count in the extension word can be taken
   // as packed epilog offset.
   if (Offset > 31 || PrologCodeBytes > 124)
-    return -1;
+    return RetVal;
 
+  // As we choose to express the epilog as part of the prolog, remove the
+  // epilog from the map, so we don't try to emit its opcodes.
   info->EpilogMap.clear();
   return Offset;
 }
@@ -952,8 +963,9 @@
 
   int PackedEpilogOffset = checkPackedEpilog(streamer, info, PrologCodeBytes);
 
-  if (PackedEpilogOffset >= 0 && !info->HandlesExceptions &&
-      FuncLength <= 0x7ff && TryPacked) {
+  if (PackedEpilogOffset >= 0 &&
+      uint32_t(PackedEpilogOffset) < PrologCodeBytes &&
+      !info->HandlesExceptions && FuncLength <= 0x7ff && TryPacked) {
     // Matching prolog/epilog and no exception handlers; check if the
     // prolog matches the patterns that can be described by the packed
     // format.
@@ -1025,17 +1037,19 @@
     streamer.emitInt32(row2);
   }
 
-  // Epilog Start Index, Epilog Start Offset
-  for (auto &I : EpilogInfo) {
-    MCSymbol *EpilogStart = I.first;
-    uint32_t EpilogIndex = I.second;
-    uint32_t EpilogOffset =
-        (uint32_t)GetAbsDifference(streamer, EpilogStart, info->Begin);
-    if (EpilogOffset)
-      EpilogOffset /= 4;
-    uint32_t row3 = EpilogOffset;
-    row3 |= (EpilogIndex & 0x3FF) << 22;
-    streamer.emitInt32(row3);
+  if (PackedEpilogOffset < 0) {
+    // Epilog Start Index, Epilog Start Offset
+    for (auto &I : EpilogInfo) {
+      MCSymbol *EpilogStart = I.first;
+      uint32_t EpilogIndex = I.second;
+      uint32_t EpilogOffset =
+          (uint32_t)GetAbsDifference(streamer, EpilogStart, info->Begin);
+      if (EpilogOffset)
+        EpilogOffset /= 4;
+      uint32_t row3 = EpilogOffset;
+      row3 |= (EpilogIndex & 0x3FF) << 22;
+      streamer.emitInt32(row3);
+    }
   }
 
   // Emit prolog unwind instructions (in reverse order).
diff --git a/llvm/test/CodeGen/AArch64/wineh1.mir b/llvm/test/CodeGen/AArch64/wineh1.mir
--- a/llvm/test/CodeGen/AArch64/wineh1.mir
+++ b/llvm/test/CodeGen/AArch64/wineh1.mir
@@ -16,8 +16,8 @@
 # CHECK-NEXT:      FunctionLength: 96
 # CHECK-NEXT:      Version: 0
 # CHECK-NEXT:      ExceptionData: No
-# CHECK-NEXT:      EpiloguePacked: No
-# CHECK-NEXT:      EpilogueScopes: 1
+# CHECK-NEXT:      EpiloguePacked: Yes
+# CHECK-NEXT:      EpilogueOffset: 13
 # CHECK-NEXT:      ByteCodeLength: 28
 # CHECK-NEXT:      Prologue [
 # CHECK-NEXT:        0xc808              ; stp x19, x20, [sp, #64]
@@ -28,21 +28,15 @@
 # CHECK-NEXT:        0xce09              ; stp x27, x28, [sp, #-80]!
 # CHECK-NEXT:        0xe4                ; end
 # CHECK-NEXT:      ]
-# CHECK-NEXT:      EpilogueScopes [
-# CHECK-NEXT:        EpilogueScope {
-# CHECK-NEXT:          StartOffset: 16
-# CHECK-NEXT:          EpilogueStartIndex: 13
-# CHECK-NEXT:          Opcodes [
-# CHECK-NEXT:            0xc808              ; ldp x19, x20, [sp, #64]
-# CHECK-NEXT:            0xd086              ; ldr x21, [sp, #48]
-# CHECK-NEXT:            0xe3                ; nop
-# CHECK-NEXT:            0xd0c7              ; ldr x22, [sp, #56]
-# CHECK-NEXT:            0xc904              ; ldp x23, x24, [sp, #32]
-# CHECK-NEXT:            0xc982              ; ldp x25, x26, [sp, #16]
-# CHECK-NEXT:            0xce09              ; ldp x27, x28, [sp], #80
-# CHECK-NEXT:            0xe4                ; end
-# CHECK-NEXT:          ]
-# CHECK-NEXT:        }
+# CHECK-NEXT:      Epilogue [
+# CHECK-NEXT:        0xc808              ; ldp x19, x20, [sp, #64]
+# CHECK-NEXT:        0xd086              ; ldr x21, [sp, #48]
+# CHECK-NEXT:        0xe3                ; nop
+# CHECK-NEXT:        0xd0c7              ; ldr x22, [sp, #56]
+# CHECK-NEXT:        0xc904              ; ldp x23, x24, [sp, #32]
+# CHECK-NEXT:        0xc982              ; ldp x25, x26, [sp, #16]
+# CHECK-NEXT:        0xce09              ; ldp x27, x28, [sp], #80
+# CHECK-NEXT:        0xe4                ; end
 # CHECK-NEXT:      ]
 # CHECK-NEXT:    }
 
diff --git a/llvm/test/CodeGen/AArch64/wineh2.mir b/llvm/test/CodeGen/AArch64/wineh2.mir
--- a/llvm/test/CodeGen/AArch64/wineh2.mir
+++ b/llvm/test/CodeGen/AArch64/wineh2.mir
@@ -6,8 +6,8 @@
 # CHECK-NEXT:      FunctionLength: 144
 # CHECK-NEXT:      Version: 0
 # CHECK-NEXT:      ExceptionData: No
-# CHECK-NEXT:      EpiloguePacked: No
-# CHECK-NEXT:      EpilogueScopes: 1
+# CHECK-NEXT:      EpiloguePacked: Yes
+# CHECK-NEXT:      EpilogueOffset: 19
 # CHECK-NEXT:      ByteCodeLength: 40
 # CHECK-NEXT:      Prologue [
 # CHECK-NEXT:        0xc80e              ; stp x19, x20, [sp, #112]
@@ -21,23 +21,17 @@
 # CHECK-NEXT:        0xde8f              ; str d12, [sp, #-128]!
 # CHECK-NEXT:        0xe4                ; end
 # CHECK-NEXT:      ]
-# CHECK-NEXT:      EpilogueScopes [
-# CHECK-NEXT:        EpilogueScope {
-# CHECK-NEXT:          StartOffset: 26
-# CHECK-NEXT:          EpilogueStartIndex: 19
-# CHECK-NEXT:          Opcodes [
-# CHECK-NEXT:            0xc80e              ; ldp x19, x20, [sp, #112]
-# CHECK-NEXT:            0xc88c              ; ldp x21, x22, [sp, #96]
-# CHECK-NEXT:            0xc90a              ; ldp x23, x24, [sp, #80]
-# CHECK-NEXT:            0xc988              ; ldp x25, x26, [sp, #64]
-# CHECK-NEXT:            0xca06              ; ldp x27, x28, [sp, #48]
-# CHECK-NEXT:            0xdc04              ; ldr d8, [sp, #32]
-# CHECK-NEXT:            0xdc45              ; ldr d9, [sp, #40]
-# CHECK-NEXT:            0xd882              ; ldp d10, d11, [sp, #16]
-# CHECK-NEXT:            0xde8f              ; ldr d12, [sp], #128
-# CHECK-NEXT:            0xe4                ; end
-# CHECK-NEXT:          ]
-# CHECK-NEXT:        }
+# CHECK-NEXT:      Epilogue [
+# CHECK-NEXT:        0xc80e              ; ldp x19, x20, [sp, #112]
+# CHECK-NEXT:        0xc88c              ; ldp x21, x22, [sp, #96]
+# CHECK-NEXT:        0xc90a              ; ldp x23, x24, [sp, #80]
+# CHECK-NEXT:        0xc988              ; ldp x25, x26, [sp, #64]
+# CHECK-NEXT:        0xca06              ; ldp x27, x28, [sp, #48]
+# CHECK-NEXT:        0xdc04              ; ldr d8, [sp, #32]
+# CHECK-NEXT:        0xdc45              ; ldr d9, [sp, #40]
+# CHECK-NEXT:        0xd882              ; ldp d10, d11, [sp, #16]
+# CHECK-NEXT:        0xde8f              ; ldr d12, [sp], #128
+# CHECK-NEXT:        0xe4                ; end
 # CHECK-NEXT:      ]
 # CHECK-NEXT:    }
 ...
diff --git a/llvm/test/CodeGen/AArch64/wineh5.mir b/llvm/test/CodeGen/AArch64/wineh5.mir
--- a/llvm/test/CodeGen/AArch64/wineh5.mir
+++ b/llvm/test/CodeGen/AArch64/wineh5.mir
@@ -7,8 +7,8 @@
 # CHECK-NEXT:     FunctionLength: 156
 # CHECK-NEXT:     Version: 0
 # CHECK-NEXT:     ExceptionData: No
-# CHECK-NEXT:     EpiloguePacked: No
-# CHECK-NEXT:     EpilogueScopes: 1
+# CHECK-NEXT:     EpiloguePacked: Yes
+# CHECK-NEXT:     EpilogueOffset: 10
 # CHECK-NEXT:     ByteCodeLength: 20
 # CHECK-NEXT:     Prologue [
 # CHECK-NEXT:       0xe002dac9          ; sub sp, #2993296
@@ -18,18 +18,12 @@
 # CHECK-NEXT:       0xd53f              ; str x28, [sp, #-256]!
 # CHECK-NEXT:       0xe4                ; end
 # CHECK-NEXT:     ]
-# CHECK-NEXT:     EpilogueScopes [
-# CHECK-NEXT:       EpilogueScope {
-# CHECK-NEXT:         StartOffset: 34
-# CHECK-NEXT:         EpilogueStartIndex: 10
-# CHECK-NEXT:         Opcodes [
-# CHECK-NEXT:           0xe002da00          ; add sp, #2990080
-# CHECK-NEXT:           0xc0c9              ; add sp, #3216
-# CHECK-NEXT:           0x42                ; ldp x29, x30, [sp, #16]
-# CHECK-NEXT:           0xd53f              ; ldr x28, [sp], #256
-# CHECK-NEXT:           0xe4                ; end
-# CHECK-NEXT:         ]
-# CHECK-NEXT:       }
+# CHECK-NEXT:     Epilogue [
+# CHECK-NEXT:       0xe002da00          ; add sp, #2990080
+# CHECK-NEXT:       0xc0c9              ; add sp, #3216
+# CHECK-NEXT:       0x42                ; ldp x29, x30, [sp, #16]
+# CHECK-NEXT:       0xd53f              ; ldr x28, [sp], #256
+# CHECK-NEXT:       0xe4                ; end
 # CHECK-NEXT:     ]
 # CHECK-NEXT:   }
 
diff --git a/llvm/test/MC/AArch64/seh-optimize.s b/llvm/test/MC/AArch64/seh-optimize.s
--- a/llvm/test/MC/AArch64/seh-optimize.s
+++ b/llvm/test/MC/AArch64/seh-optimize.s
@@ -27,17 +27,13 @@
 // CHECK-NEXT:         0xe201              ; add fp, sp, #8
 // CHECK-NEXT:         0xe4                ; end
 // CHECK-NEXT:       ]
-// CHECK-NEXT:       EpilogueScopes [
-// CHECK-NEXT:         EpilogueScope {
-// CHECK:                Opcodes [
-// CHECK-NEXT:             0xc904              ; ldp x23, x24, [sp, #32]
-// CHECK-NEXT:             0xe6                ; restore next
-// CHECK-NEXT:             0xcc83              ; ldp x21, x22, [sp], #32
-// CHECK-NEXT:             0x24                ; ldp x19, x20, [sp], #32
-// CHECK-NEXT:             0xcc1f              ; ldp x19, x20, [sp], #256
-// CHECK-NEXT:             0xe4                ; end
-// CHECK-NEXT:           ]
-// CHECK-NEXT:         }
+// CHECK-NEXT:       Epilogue [
+// CHECK-NEXT:         0xc904              ; ldp x23, x24, [sp, #32]
+// CHECK-NEXT:         0xe6                ; restore next
+// CHECK-NEXT:         0xcc83              ; ldp x21, x22, [sp], #32
+// CHECK-NEXT:         0x24                ; ldp x19, x20, [sp], #32
+// CHECK-NEXT:         0xcc1f              ; ldp x19, x20, [sp], #256
+// CHECK-NEXT:         0xe4                ; end
 // CHECK-NEXT:       ]
 // CHECK-NEXT:     }
 // CHECK-NEXT:   }
diff --git a/llvm/test/MC/AArch64/seh-packed-epilog.s b/llvm/test/MC/AArch64/seh-packed-epilog.s
--- a/llvm/test/MC/AArch64/seh-packed-epilog.s
+++ b/llvm/test/MC/AArch64/seh-packed-epilog.s
@@ -43,6 +43,13 @@
 // CHECK-NEXT:     ExceptionData {
 // CHECK:            ExceptionData:
 // CHECK-NEXT:       EpiloguePacked: Yes
+// CHECK-NEXT:       EpilogueOffset: 0
+// CHECK-NEXT:       ByteCodeLength: 4
+// CHECK-NEXT:       Prologue [
+// CHECK-NEXT:         0x83                ; stp x29, x30, [sp, #-32]!
+// CHECK-NEXT:         0x03                ; sub sp, #48
+// CHECK-NEXT:         0xe4                ; end
+// CHECK-NEXT:       ]
 // CHECK:        RuntimeFunction {
 // CHECK-NEXT:     Function: nonpacked1
 // CHECK-NEXT:     ExceptionRecord:
@@ -50,17 +57,42 @@
 // CHECK:            ExceptionData:
 // CHECK-NEXT:       EpiloguePacked: No
 // CHECK:        RuntimeFunction {
-// CHECK-NEXT:     Function: nonpacked2
+// CHECK-NEXT:     Function: nonshared2
 // CHECK-NEXT:     ExceptionRecord:
 // CHECK-NEXT:     ExceptionData {
 // CHECK:            ExceptionData:
-// CHECK-NEXT:       EpiloguePacked: No
+// CHECK-NEXT:       EpiloguePacked: Yes
+// CHECK-NEXT:       EpilogueOffset: 3
+// CHECK-NEXT:       ByteCodeLength: 8
+// CHECK-NEXT:       Prologue [
+// CHECK-NEXT:         0x02                ; sub sp, #32
+// CHECK-NEXT:         0x03                ; sub sp, #48
+// CHECK-NEXT:         0xe4                ; end
+// CHECK-NEXT:       ]
+// CHECK-NEXT:       Epilogue [
+// CHECK-NEXT:         0x01                ; add sp, #16
+// CHECK-NEXT:         0x03                ; add sp, #48
+// CHECK-NEXT:         0xe4                ; end
+// CHECK-NEXT:       ]
 // CHECK:        RuntimeFunction {
-// CHECK-NEXT:     Function: nonpacked3
+// CHECK-NEXT:     Function: nonshared3
 // CHECK-NEXT:     ExceptionRecord:
 // CHECK-NEXT:     ExceptionData {
 // CHECK:            ExceptionData:
-// CHECK-NEXT:       EpiloguePacked: No
+// CHECK-NEXT:       EpiloguePacked: Yes
+// CHECK-NEXT:       EpilogueOffset: 3
+// CHECK-NEXT:       ByteCodeLength: 8
+// CHECK-NEXT:       Prologue [
+// CHECK-NEXT:         0x02                ; sub sp, #32
+// CHECK-NEXT:         0x03                ; sub sp, #48
+// CHECK-NEXT:         0xe4                ; end
+// CHECK-NEXT:       ]
+// CHECK-NEXT:       Epilogue [
+// CHECK-NEXT:         0xe1                ; mov sp, fp
+// CHECK-NEXT:         0x02                ; add sp, #32
+// CHECK-NEXT:         0x03                ; add sp, #48
+// CHECK-NEXT:         0xe4                ; end
+// CHECK-NEXT:       ]
 
     .text
     .globl func
@@ -146,8 +178,8 @@
     .seh_endproc
 
 
-    .seh_proc nonpacked2
-nonpacked2:
+    .seh_proc nonshared2
+nonshared2:
     sub sp, sp, #48
     .seh_stackalloc 48
     sub sp, sp, #32
@@ -156,7 +188,7 @@
 
     nop
     .seh_startepilogue
-    // Not packed; the epilogue mismatches at the second opcode.
+    // Not shared; the epilogue mismatches at the second opcode.
     add sp, sp, #16
     .seh_stackalloc 16
     add sp, sp, #48
@@ -165,8 +197,8 @@
     ret
     .seh_endproc
 
-    .seh_proc nonpacked3
-nonpacked3:
+    .seh_proc nonshared3
+nonshared3:
     sub sp, sp, #48
     .seh_stackalloc 48
     sub sp, sp, #32
@@ -175,7 +207,7 @@
 
     nop
     .seh_startepilogue
-    // Not packed; the epilogue is longer than the prologue.
+    // Not shared; the epilogue is longer than the prologue.
     mov sp, x29
     .seh_set_fp
     add sp, sp, #32