Index: llvm/trunk/include/llvm/IR/LLVMContext.h
===================================================================
--- llvm/trunk/include/llvm/IR/LLVMContext.h
+++ llvm/trunk/include/llvm/IR/LLVMContext.h
@@ -315,9 +315,16 @@
     return OptionRegistry::instance().template get<ValT, Base, Mem>();
   }
 
-  /// \brief Access the object which manages optimization bisection for failure
-  /// analysis.
-  OptPassGate &getOptPassGate();
+  /// \brief Access the object which can disable optional passes and individual
+  /// optimizations at compile time.
+  OptPassGate &getOptPassGate() const;
+
+  /// \brief Set the object which can disable optional passes and individual
+  /// optimizations at compile time.
+  ///
+  /// The lifetime of the object must be guaranteed to extend as long as the
+  /// LLVMContext is used by compilation.
+  void setOptPassGate(OptPassGate&);
 
 private:
   // Module needs access to the add/removeModule methods.
Index: llvm/trunk/lib/IR/LLVMContext.cpp
===================================================================
--- llvm/trunk/lib/IR/LLVMContext.cpp
+++ llvm/trunk/lib/IR/LLVMContext.cpp
@@ -332,10 +332,14 @@
   pImpl->DiscardValueNames = Discard;
 }
 
-OptPassGate &LLVMContext::getOptPassGate() {
+OptPassGate &LLVMContext::getOptPassGate() const {
   return pImpl->getOptPassGate();
 }
 
+void LLVMContext::setOptPassGate(OptPassGate& OPG) {
+  pImpl->setOptPassGate(OPG);
+}
+
 const DiagnosticHandler *LLVMContext::getDiagHandlerPtr() const {
   return pImpl->DiagHandler.get();
 }
Index: llvm/trunk/lib/IR/LLVMContextImpl.h
===================================================================
--- llvm/trunk/lib/IR/LLVMContextImpl.h
+++ llvm/trunk/lib/IR/LLVMContextImpl.h
@@ -1355,9 +1355,18 @@
   /// Destroy the ConstantArrays if they are not used.
   void dropTriviallyDeadConstantArrays();
 
-  /// \brief Access the object which manages optimization bisection for failure
-  /// analysis.
-  OptPassGate &getOptPassGate();
+  mutable OptPassGate *OPG = nullptr;
+
+  /// \brief Access the object which can disable optional passes and individual
+  /// optimizations at compile time.
+  OptPassGate &getOptPassGate() const;
+
+  /// \brief Set the object which can disable optional passes and individual
+  /// optimizations at compile time.
+  ///
+  /// The lifetime of the object must be guaranteed to extend as long as the
+  /// LLVMContext is used by compilation.
+  void setOptPassGate(OptPassGate&);
 };
 
 } // end namespace llvm
Index: llvm/trunk/lib/IR/LLVMContextImpl.cpp
===================================================================
--- llvm/trunk/lib/IR/LLVMContextImpl.cpp
+++ llvm/trunk/lib/IR/LLVMContextImpl.cpp
@@ -233,6 +233,12 @@
 /// enabled in order to enable a consistent bisect count.
 static ManagedStatic<OptBisect> OptBisector;
 
-OptPassGate &LLVMContextImpl::getOptPassGate() {
-  return *OptBisector;
+OptPassGate &LLVMContextImpl::getOptPassGate() const {
+  if (!OPG)
+    OPG = &(*OptBisector);
+  return *OPG;
+}
+
+void LLVMContextImpl::setOptPassGate(OptPassGate& OPG) {
+  this->OPG = &OPG;
 }
Index: llvm/trunk/unittests/IR/LegacyPassManagerTest.cpp
===================================================================
--- llvm/trunk/unittests/IR/LegacyPassManagerTest.cpp
+++ llvm/trunk/unittests/IR/LegacyPassManagerTest.cpp
@@ -26,6 +26,7 @@
 #include "llvm/IR/Instructions.h"
 #include "llvm/IR/LLVMContext.h"
 #include "llvm/IR/Module.h"
+#include "llvm/IR/OptBisect.h"
 #include "llvm/Pass.h"
 #include "llvm/Support/MathExtras.h"
 #include "llvm/Support/raw_ostream.h"
@@ -396,6 +397,67 @@
       delete M;
     }
 
+    // Skips or runs optional passes.
+    struct CustomOptPassGate : public OptPassGate {
+      bool Skip;
+      CustomOptPassGate(bool Skip) : Skip(Skip) { }
+      bool shouldRunPass(const Pass *P, const Module &U) { return !Skip; }
+    };
+
+    // Optional module pass.
+    struct ModuleOpt: public ModulePass {
+      char run = 0;
+      static char ID;
+      ModuleOpt() : ModulePass(ID) { }
+      bool runOnModule(Module &M) override {
+        if (!skipModule(M))
+          run++;
+        return false;
+      }
+    };
+    char ModuleOpt::ID=0;
+
+    TEST(PassManager, CustomOptPassGate) {
+      LLVMContext Context0;
+      LLVMContext Context1;
+      LLVMContext Context2;
+      CustomOptPassGate SkipOptionalPasses(true);
+      CustomOptPassGate RunOptionalPasses(false);
+
+      Module M0("custom-opt-bisect", Context0);
+      Module M1("custom-opt-bisect", Context1);
+      Module M2("custom-opt-bisect2", Context2);
+      struct ModuleOpt *mOpt0 = new ModuleOpt();
+      struct ModuleOpt *mOpt1 = new ModuleOpt();
+      struct ModuleOpt *mOpt2 = new ModuleOpt();
+
+      mOpt0->run = mOpt1->run = mOpt2->run = 0;
+
+      legacy::PassManager Passes0;
+      legacy::PassManager Passes1;
+      legacy::PassManager Passes2;
+
+      Passes0.add(mOpt0);
+      Passes1.add(mOpt1);
+      Passes2.add(mOpt2);
+
+      Context1.setOptPassGate(SkipOptionalPasses);
+      Context2.setOptPassGate(RunOptionalPasses);
+
+      Passes0.run(M0);
+      Passes1.run(M1);
+      Passes2.run(M2);
+
+      // By default optional passes are run.
+      EXPECT_EQ(1, mOpt0->run);
+
+      // The first context skips optional passes.
+      EXPECT_EQ(0, mOpt1->run);
+
+      // The second context runs optional passes.
+      EXPECT_EQ(1, mOpt2->run);
+    }
+
     Module *makeLLVMModule(LLVMContext &Context) {
       // Module Construction
       Module *mod = new Module("test-mem", Context);