diff --git a/lib/Driver/Driver.cpp b/lib/Driver/Driver.cpp
index 7a0defe..f6016b4 100644
--- a/lib/Driver/Driver.cpp
+++ b/lib/Driver/Driver.cpp
@@ -1802,23 +1802,36 @@
   return true;
 }
 
+enum {
+  TopLevelAction = 0,
+  HeadSibAction = 1,
+  OtherSibAction = 2,
+};
+
 // Display an action graph human-readably.  Action A is the "sink" node
 // and latest-occuring action. Traversal is in pre-order, visiting the
 // inputs to each action before printing the action itself.
 static unsigned PrintActions1(const Compilation &C, Action *A,
-                              std::map<Action *, unsigned> &Ids) {
+                              std::map<Action *, unsigned> &Ids,
+                              Twine Indent = {}, int Kind = TopLevelAction) {
   if (Ids.count(A)) // A was already visited.
     return Ids[A];
 
   std::string str;
   llvm::raw_string_ostream os(str);
 
+  auto getSibIndent = [](int K) -> Twine {
+    return (K == HeadSibAction) ? "   " : (K == OtherSibAction) ? "|  " : "";
+  };
+
+  Twine SibIndent = Indent + getSibIndent(Kind);
+  int SibKind = HeadSibAction;
   os << Action::getClassName(A->getKind()) << ", ";
   if (InputAction *IA = dyn_cast<InputAction>(A)) {
     os << "\"" << IA->getInputArg().getValue() << "\"";
   } else if (BindArchAction *BIA = dyn_cast<BindArchAction>(A)) {
     os << '"' << BIA->getArchName() << '"' << ", {"
-       << PrintActions1(C, *BIA->input_begin(), Ids) << "}";
+       << PrintActions1(C, *BIA->input_begin(), Ids, SibIndent, SibKind) << "}";
   } else if (OffloadAction *OA = dyn_cast<OffloadAction>(A)) {
     bool IsFirst = true;
     OA->doOnEachDependence(
@@ -1841,8 +1854,9 @@
             os << ":" << BoundArch;
           os << ")";
           os << '"';
-          os << " {" << PrintActions1(C, A, Ids) << "}";
+          os << " {" << PrintActions1(C, A, Ids, SibIndent, SibKind) << "}";
           IsFirst = false;
+          SibKind = OtherSibAction;
         });
   } else {
     const ActionList *AL = &A->getInputs();
@@ -1850,8 +1864,9 @@
     if (AL->size()) {
       const char *Prefix = "{";
       for (Action *PreRequisite : *AL) {
-        os << Prefix << PrintActions1(C, PreRequisite, Ids);
+        os << Prefix << PrintActions1(C, PreRequisite, Ids, SibIndent, SibKind);
         Prefix = ", ";
+        SibKind = OtherSibAction;
       }
       os << "}";
     } else
@@ -1872,9 +1887,13 @@
     }
   }
 
+  auto getSelfIndent = [](int K) -> Twine {
+    return (K == HeadSibAction) ? "+- " : (K == OtherSibAction) ? "|- " : "";
+  };
+
   unsigned Id = Ids.size();
   Ids[A] = Id;
-  llvm::errs() << Id << ": " << os.str() << ", "
+  llvm::errs() << Indent + getSelfIndent(Kind) << Id << ": " << os.str() << ", "
                << types::getTypeName(A->getType()) << offload_os.str() << "\n";
 
   return Id;