Index: llvm/trunk/lib/Passes/PassBuilder.cpp
===================================================================
--- llvm/trunk/lib/Passes/PassBuilder.cpp
+++ llvm/trunk/lib/Passes/PassBuilder.cpp
@@ -150,6 +150,10 @@
 
 static cl::opt<unsigned> MaxDevirtIterations("pm-max-devirt-iterations",
                                              cl::ReallyHidden, cl::init(4));
+static cl::opt<bool>
+    RunPartialInlining("enable-npm-partial-inlining", cl::init(false),
+                       cl::Hidden, cl::ZeroOrMore,
+                       cl::desc("Run Partial inlinining pass"));
 
 static cl::opt<bool> EnableGVNHoist(
     "enable-npm-gvn-hoist", cl::init(false), cl::Hidden,
@@ -552,6 +556,11 @@
   // At this point, we expect to have canonical and simple IR which we begin
   // *optimizing* for efficient execution going forward.
 
+  // Run partial inlining pass to partially inline functions that have
+  // large bodies.
+  if (RunPartialInlining)
+    MPM.addPass(PartialInlinerPass());
+
   // Eliminate externally available functions now that inlining is over -- we
   // won't emit these anyways.
   MPM.addPass(EliminateAvailableExternallyPass());
Index: llvm/trunk/lib/Transforms/IPO/PassManagerBuilder.cpp
===================================================================
--- llvm/trunk/lib/Transforms/IPO/PassManagerBuilder.cpp
+++ llvm/trunk/lib/Transforms/IPO/PassManagerBuilder.cpp
@@ -44,8 +44,12 @@
 using namespace llvm;
 
 static cl::opt<bool>
-RunLoopVectorization("vectorize-loops", cl::Hidden,
-                     cl::desc("Run the Loop vectorization passes"));
+    RunPartialInlining("enable-partial-inlining", cl::init(false), cl::Hidden,
+                       cl::ZeroOrMore, cl::desc("Run Partial inlinining pass"));
+
+static cl::opt<bool>
+    RunLoopVectorization("vectorize-loops", cl::Hidden,
+                         cl::desc("Run the Loop vectorization passes"));
 
 static cl::opt<bool>
 RunSLPVectorization("vectorize-slp", cl::Hidden,
@@ -516,6 +520,8 @@
   // pass manager that we are specifically trying to avoid. To prevent this
   // we must insert a no-op module pass to reset the pass manager.
   MPM.add(createBarrierNoopPass());
+  if (RunPartialInlining)
+    MPM.add(createPartialInliningPass());
 
   if (!DisableUnitAtATime && OptLevel > 1 && !PrepareForLTO &&
       !PrepareForThinLTO)