diff --git a/llvm/lib/Transforms/IPO/MemProfContextDisambiguation.cpp b/llvm/lib/Transforms/IPO/MemProfContextDisambiguation.cpp
index cff38a8e68c6a..f28fe51fb6a5a 100644
--- a/llvm/lib/Transforms/IPO/MemProfContextDisambiguation.cpp
+++ b/llvm/lib/Transforms/IPO/MemProfContextDisambiguation.cpp
@@ -2183,6 +2183,9 @@ ModuleCallsiteContextGraph::ModuleCallsiteContextGraph(
 
   updateStackNodes();
 
+  if (ExportToDot)
+    exportToDot("poststackupdate");
+
   handleCallsitesWithMultipleTargets();
 
   markBackedges();
@@ -2285,6 +2288,9 @@ IndexCallsiteContextGraph::IndexCallsiteContextGraph(
 
   updateStackNodes();
 
+  if (ExportToDot)
+    exportToDot("poststackupdate");
+
   handleCallsitesWithMultipleTargets();
 
   markBackedges();
diff --git a/llvm/test/Transforms/MemProfContextDisambiguation/duplicate-context-ids.ll b/llvm/test/Transforms/MemProfContextDisambiguation/duplicate-context-ids.ll
index 93557e963752e..18521c013d555 100644
--- a/llvm/test/Transforms/MemProfContextDisambiguation/duplicate-context-ids.ll
+++ b/llvm/test/Transforms/MemProfContextDisambiguation/duplicate-context-ids.ll
@@ -64,6 +64,10 @@
 ; RUN:  --check-prefix=STATS --check-prefix=REMARKS
 
 ; RUN:  cat %t.ccg.prestackupdate.dot | FileCheck %s --check-prefix=DOTPRE
+;; There are no changes for this test case in between from immediately after
+;; the stack update through the end of graph finalization, so the
+;; corresponding dot graphs should be identical.
+; RUN:  cat %t.ccg.poststackupdate.dot | FileCheck %s --check-prefix=DOTPOST
 ; RUN:  cat %t.ccg.postbuild.dot | FileCheck %s --check-prefix=DOTPOST
 ;; We should clone D once for the cold allocations via C.
 ; RUN:  cat %t.ccg.cloned.dot | FileCheck %s --check-prefix=DOTCLONED
@@ -313,8 +317,8 @@ attributes #6 = { builtin }
 ; DOTPRE: }
 
 
-; DOTPOST:digraph "postbuild" {
-; DOTPOST:	label="postbuild";
+; DOTPOST:digraph "post
+; DOTPOST:	label="post
 ; DOTPOST:	Node[[D:0x[a-z0-9]+]] [shape=record,tooltip="N[[D]] ContextIds: 1 2 3 4",fillcolor="mediumorchid1",style="filled",label="{OrigId: Alloc0\n_Z1Dv -\> _Znam}"];
 ; DOTPOST:	Node[[F:0x[a-z0-9]+]] [shape=record,tooltip="N[[F]] ContextIds: 2",fillcolor="brown1",style="filled",label="{OrigId: 13543580133643026784\n_Z1Fv -\> _Z1Dv}"];
 ; DOTPOST:	Node[[F]] -> Node[[D]][tooltip="ContextIds: 2",fillcolor="brown1"
diff --git a/llvm/test/Transforms/MemProfContextDisambiguation/tailcall-nonunique.ll b/llvm/test/Transforms/MemProfContextDisambiguation/tailcall-nonunique.ll
index 985c381ad42ff..97e433ccefa99 100644
--- a/llvm/test/Transforms/MemProfContextDisambiguation/tailcall-nonunique.ll
+++ b/llvm/test/Transforms/MemProfContextDisambiguation/tailcall-nonunique.ll
@@ -6,11 +6,20 @@
 ; REQUIRES: asserts
 
 ; RUN: opt -passes=memprof-context-disambiguation -supports-hot-cold-new \
+; RUN:	-memprof-export-to-dot -memprof-dot-file-path-prefix=%t. \
 ; RUN:  -stats -debug %s -S 2>&1 | FileCheck %s --check-prefix=STATS \
 ; RUN:  --check-prefix=IR --check-prefix=DEBUG
 
 ; DEBUG: Not found through unique tail call chain: _Z3barv from main that actually called xyz (found multiple possible chains)
 
+;; Graph fixup should have nulled the call in the node that could not be
+;; resolved via tail call fixup. That happens in between the initial
+;; stack update and the end of graph building.
+; RUN:  cat %t.ccg.poststackupdate.dot | FileCheck %s --check-prefix=DOTPOSTSTACKUPDATE
+; DOTPOSTSTACKUPDATE: {OrigId: 15025054523792398438\nmain -\> xyz}
+; RUN:  cat %t.ccg.postbuild.dot | FileCheck %s --check-prefix=DOTPOSTBUILD
+; DOTPOSTBUILD: {OrigId: 15025054523792398438\nnull call (external)}
+
 ;; Check that all calls in the IR are to the original functions, leading to a
 ;; non-cold operator new call.