Index: lib/CodeGen/MicrosoftCXXABI.cpp
===================================================================
--- lib/CodeGen/MicrosoftCXXABI.cpp
+++ lib/CodeGen/MicrosoftCXXABI.cpp
@@ -149,6 +149,12 @@
   virtual llvm::Constant *EmitMemberDataPointer(const MemberPointerType *MPT,
                                                 CharUnits offset);
 
+  virtual llvm::Value *EmitMemberPointerComparison(CodeGenFunction &CGF,
+                                                   llvm::Value *L,
+                                                   llvm::Value *R,
+                                                   const MemberPointerType *MPT,
+                                                   bool Inequality);
+
   virtual llvm::Value *EmitMemberPointerIsNotNull(CodeGenFunction &CGF,
                                                   llvm::Value *MemPtr,
                                                   const MemberPointerType *MPT);
@@ -415,6 +421,10 @@
   return Inheritance == MSIM_Unspecified;
 }
 
+static bool hasOnlyOneField(MSInheritanceModel Inheritance) {
+  return Inheritance <= MSIM_SinglePolymorphic;
+}
+
 // Only member pointers to functions need a this adjustment, since it can be
 // combined with the field offset for data pointers.
 static bool hasNonVirtualBaseAdjustmentField(const MemberPointerType *MPT,
@@ -531,6 +541,66 @@
   return llvm::ConstantStruct::getAnon(fields);
 }
 
+/// Member pointers are the same if they're either bitwise identical *or* both
+/// null.  Null-ness for function members is determined by the first field,
+/// while for data member pointers we must compare all fields.
+llvm::Value *
+MicrosoftCXXABI::EmitMemberPointerComparison(CodeGenFunction &CGF,
+                                             llvm::Value *L,
+                                             llvm::Value *R,
+                                             const MemberPointerType *MPT,
+                                             bool Inequality) {
+  CGBuilderTy &Builder = CGF.Builder;
+  llvm::ICmpInst::Predicate Eq;
+  llvm::Instruction::BinaryOps And, Or;
+  if (Inequality) {
+    Eq = llvm::ICmpInst::ICMP_NE;
+    And = llvm::Instruction::Or;
+    Or = llvm::Instruction::And;
+  } else {
+    Eq = llvm::ICmpInst::ICMP_EQ;
+    And = llvm::Instruction::And;
+    Or = llvm::Instruction::Or;
+  }
+
+  // If this is a single field member pointer (single inheritance), this is a
+  // single icmp.
+  const CXXRecordDecl *RD = MPT->getClass()->getAsCXXRecordDecl();
+  MSInheritanceModel Inheritance = RD->getMSInheritanceModel();
+  if (hasOnlyOneField(Inheritance))
+    return Builder.CreateICmp(Eq, L, R);
+
+  // Compare the first field.
+  llvm::Value *L0 = Builder.CreateExtractValue(L, 0, "lhs.0");
+  llvm::Value *R0 = Builder.CreateExtractValue(R, 0, "rhs.0");
+  llvm::Value *Cmp0 = Builder.CreateICmp(Eq, L0, R0);
+
+  // Compare everything other than the first field.
+  llvm::Value *Res = 0;
+  for (unsigned I = 1, E = cast<llvm::StructType>(L->getType())->getNumElements();
+       I != E; ++I) {
+    llvm::Value *LField = Builder.CreateExtractValue(L, I);
+    llvm::Value *RField = Builder.CreateExtractValue(R, I);
+    llvm::Value *Cmp = Builder.CreateICmp(Eq, LField, RField);
+    if (Res)
+      Res = Builder.CreateBinOp(And, Res, Cmp, "memptr.tobool");
+    else
+      Res = Cmp;
+  }
+
+  // Check if the first field is 0 if this is a function pointer.
+  if (MPT->isMemberFunctionPointer()) {
+    // (l1 == r1 && ...) || l0 == 0
+    llvm::Value *Zero = llvm::Constant::getNullValue(L0->getType());
+    llvm::Value *IsZero = Builder.CreateICmp(Eq, L0, Zero);
+    Res = Builder.CreateBinOp(Or, Res, IsZero, "memptr.tobool");
+  }
+
+  // Combine the comparison of the first field, which must always be true for
+  // this comparison to succeeed.
+  return Builder.CreateBinOp(And, Res, Cmp0, "memptr.tobool");
+}
+
 llvm::Value *
 MicrosoftCXXABI::EmitMemberPointerIsNotNull(CodeGenFunction &CGF,
                                             llvm::Value *MemPtr,
Index: test/CodeGenCXX/microsoft-abi-member-pointers.cpp
===================================================================
--- test/CodeGenCXX/microsoft-abi-member-pointers.cpp
+++ test/CodeGenCXX/microsoft-abi-member-pointers.cpp
@@ -222,3 +222,91 @@
 // CHECK:   ret void
 // CHECK: }
 }
+
+bool compareSingleFunctionMemptr(void (Single::*l)(), void (Single::*r)()) {
+  return l == r;
+// Should only be one comparison here.
+// CHECK: define zeroext i1 @"\01?compareSingleFunctionMemptr@@YA_NP8Single@@AEXXZ0@Z"{{.*}} {
+// CHECK-NOT: icmp
+// CHECK:   %[[r:.*]] = icmp eq
+// CHECK-NOT: icmp
+// CHECK:   ret i1 %[[r]]
+// CHECK: }
+}
+
+bool compareNeqSingleFunctionMemptr(void (Single::*l)(), void (Single::*r)()) {
+  return l != r;
+// Should only be one comparison here.
+// CHECK: define zeroext i1 @"\01?compareNeqSingleFunctionMemptr@@YA_NP8Single@@AEXXZ0@Z"{{.*}} {
+// CHECK-NOT: icmp
+// CHECK:   %[[r:.*]] = icmp ne
+// CHECK-NOT: icmp
+// CHECK:   ret i1 %[[r]]
+// CHECK: }
+}
+
+bool unspecFuncMemptrEq(void (Unspecified::*l)(), void (Unspecified::*r)()) {
+  return l == r;
+// CHECK: define zeroext i1 @"\01?unspecFuncMemptrEq@@YA_NP8Unspecified@@AEXXZ0@Z"{{.*}} {
+// CHECK:   %[[lhs0:.*]] = extractvalue { i8*, i32, i32, i32 } %[[l:.*]], 0
+// CHECK:   %{{.*}} = extractvalue { i8*, i32, i32, i32 } %[[r:.*]], 0
+// CHECK:   %[[cmp0:.*]] = icmp eq i8* %[[lhs0]], %{{.*}}
+// CHECK:   %{{.*}} = extractvalue { i8*, i32, i32, i32 } %[[l]], 1
+// CHECK:   %{{.*}} = extractvalue { i8*, i32, i32, i32 } %[[r]], 1
+// CHECK:   %[[cmp1:.*]] = icmp eq i32
+// CHECK:   %{{.*}} = extractvalue { i8*, i32, i32, i32 } %[[l]], 2
+// CHECK:   %{{.*}} = extractvalue { i8*, i32, i32, i32 } %[[r]], 2
+// CHECK:   %[[cmp2:.*]] = icmp eq i32
+// CHECK:   %[[res12:.*]] = and i1 %[[cmp1]], %[[cmp2]]
+// CHECK:   %{{.*}} = extractvalue { i8*, i32, i32, i32 } %[[l]], 3
+// CHECK:   %{{.*}} = extractvalue { i8*, i32, i32, i32 } %[[r]], 3
+// CHECK:   %[[cmp3:.*]] = icmp eq i32
+// CHECK:   %[[res123:.*]] = and i1 %[[res12]], %[[cmp3]]
+// CHECK:   %[[iszero:.*]] = icmp eq i8* %[[lhs0]], null
+// CHECK:   %[[bits_or_null:.*]] = or i1 %[[res123]], %[[iszero]]
+// CHECK:   %{{.*}} = and i1 %[[bits_or_null]], %[[cmp0]]
+// CHECK:   ret i1 %{{.*}}
+// CHECK: }
+}
+
+bool unspecFuncMemptrNeq(void (Unspecified::*l)(), void (Unspecified::*r)()) {
+  return l != r;
+// CHECK: define zeroext i1 @"\01?unspecFuncMemptrNeq@@YA_NP8Unspecified@@AEXXZ0@Z"{{.*}} {
+// CHECK:   %[[lhs0:.*]] = extractvalue { i8*, i32, i32, i32 } %[[l:.*]], 0
+// CHECK:   %{{.*}} = extractvalue { i8*, i32, i32, i32 } %[[r:.*]], 0
+// CHECK:   %[[cmp0:.*]] = icmp ne i8* %[[lhs0]], %{{.*}}
+// CHECK:   %{{.*}} = extractvalue { i8*, i32, i32, i32 } %[[l]], 1
+// CHECK:   %{{.*}} = extractvalue { i8*, i32, i32, i32 } %[[r]], 1
+// CHECK:   %[[cmp1:.*]] = icmp ne i32
+// CHECK:   %{{.*}} = extractvalue { i8*, i32, i32, i32 } %[[l]], 2
+// CHECK:   %{{.*}} = extractvalue { i8*, i32, i32, i32 } %[[r]], 2
+// CHECK:   %[[cmp2:.*]] = icmp ne i32
+// CHECK:   %[[res12:.*]] = or i1 %[[cmp1]], %[[cmp2]]
+// CHECK:   %{{.*}} = extractvalue { i8*, i32, i32, i32 } %[[l]], 3
+// CHECK:   %{{.*}} = extractvalue { i8*, i32, i32, i32 } %[[r]], 3
+// CHECK:   %[[cmp3:.*]] = icmp ne i32
+// CHECK:   %[[res123:.*]] = or i1 %[[res12]], %[[cmp3]]
+// CHECK:   %[[iszero:.*]] = icmp ne i8* %[[lhs0]], null
+// CHECK:   %[[bits_or_null:.*]] = and i1 %[[res123]], %[[iszero]]
+// CHECK:   %{{.*}} = or i1 %[[bits_or_null]], %[[cmp0]]
+// CHECK:   ret i1 %{{.*}}
+// CHECK: }
+}
+
+bool unspecDataMemptrEq(int Unspecified::*l, int Unspecified::*r) {
+  return l == r;
+// CHECK: define zeroext i1 @"\01?unspecDataMemptrEq@@YA_NPQUnspecified@@H0@Z"{{.*}} {
+// CHECK:   extractvalue { i32, i32, i32 } %{{.*}}, 0
+// CHECK:   extractvalue { i32, i32, i32 } %{{.*}}, 0
+// CHECK:   icmp eq i32
+// CHECK:   extractvalue { i32, i32, i32 } %{{.*}}, 1
+// CHECK:   extractvalue { i32, i32, i32 } %{{.*}}, 1
+// CHECK:   icmp eq i32
+// CHECK:   extractvalue { i32, i32, i32 } %{{.*}}, 2
+// CHECK:   extractvalue { i32, i32, i32 } %{{.*}}, 2
+// CHECK:   icmp eq i32
+// CHECK:   and i1
+// CHECK:   and i1
+// CHECK:   ret i1
+// CHECK: }
+}