Index: lib/Sema/SemaCoroutine.cpp
===================================================================
--- lib/Sema/SemaCoroutine.cpp
+++ lib/Sema/SemaCoroutine.cpp
@@ -510,6 +510,20 @@
   // Build a list of arguments, based on the coroutine functions arguments,
   // that will be passed to the promise type's constructor.
   llvm::SmallVector<Expr *, 4> CtorArgExprs;
+
+  // Add implicit object parameter.
+  if (auto *MD = dyn_cast<CXXMethodDecl>(FD)) {
+    if (MD->isInstance() && !isLambdaCallOperator(MD)) {
+      ExprResult ThisExpr = ActOnCXXThis(Loc);
+      if (ThisExpr.isInvalid())
+        return nullptr;
+      ThisExpr = CreateBuiltinUnaryOp(Loc, UO_Deref, ThisExpr.get());
+      if (ThisExpr.isInvalid())
+        return nullptr;
+      CtorArgExprs.push_back(ThisExpr.get());
+    }
+  }
+
   auto &Moves = ScopeInfo->CoroutineParameterMoves;
   for (auto *PD : FD->parameters()) {
     if (PD->getType()->isDependentType())
Index: test/CodeGenCoroutines/coro-params.cpp
===================================================================
--- test/CodeGenCoroutines/coro-params.cpp
+++ test/CodeGenCoroutines/coro-params.cpp
@@ -156,3 +156,28 @@
   // CHECK: invoke void @_ZNSt12experimental16coroutine_traitsIJv28promise_matching_constructorifdEE12promise_typeC1ES1_ifd(%"struct.std::experimental::coroutine_traits<void, promise_matching_constructor, int, float, double>::promise_type"* %__promise, i32 %[[INT]], float %[[FLOAT]], double %[[DOUBLE]])
   co_return;
 }
+
+struct some_class;
+
+struct method {};
+
+template <typename... Args> struct std::experimental::coroutine_traits<method, Args...> {
+  struct promise_type {
+    promise_type(some_class&, float);
+    method get_return_object();
+    suspend_always initial_suspend();
+    suspend_always final_suspend();
+    void return_void();
+    void unhandled_exception();
+  };
+};
+
+struct some_class {
+  method good_coroutine_calls_custom_constructor(float);
+};
+
+// CHECK-LABEL: define void @_ZN10some_class39good_coroutine_calls_custom_constructorEf(%struct.some_class*
+method some_class::good_coroutine_calls_custom_constructor(float) {
+  // CHECK: invoke void @_ZNSt12experimental16coroutine_traitsIJ6methodR10some_classfEE12promise_typeC1ES3_f(%"struct.std::experimental::coroutine_traits<method, some_class &, float>::promise_type"* %__promise, %struct.some_class* dereferenceable(1) %{{.+}}, float
+  co_return;
+}
Index: test/SemaCXX/coroutines.cpp
===================================================================
--- test/SemaCXX/coroutines.cpp
+++ test/SemaCXX/coroutines.cpp
@@ -831,7 +831,7 @@
   };
 };
 
-extern "C" int f(mismatch_gro_type_tag1) { 
+extern "C" int f(mismatch_gro_type_tag1) {
   // expected-error@-1 {{cannot initialize return object of type 'int' with an rvalue of type 'void'}}
   co_return; //expected-note {{function is a coroutine due to use of 'co_return' here}}
 }
@@ -848,7 +848,7 @@
   };
 };
 
-extern "C" int f(mismatch_gro_type_tag2) { 
+extern "C" int f(mismatch_gro_type_tag2) {
   // expected-error@-1 {{cannot initialize return object of type 'int' with an lvalue of type 'void *'}}
   co_return; //expected-note {{function is a coroutine due to use of 'co_return' here}}
 }
@@ -866,7 +866,7 @@
   };
 };
 
-extern "C" int f(mismatch_gro_type_tag3) { 
+extern "C" int f(mismatch_gro_type_tag3) {
   // expected-error@-1 {{cannot initialize return object of type 'int' with an rvalue of type 'void'}}
   co_return; //expected-note {{function is a coroutine due to use of 'co_return' here}}
 }
@@ -885,7 +885,7 @@
   };
 };
 
-extern "C" int f(mismatch_gro_type_tag4) { 
+extern "C" int f(mismatch_gro_type_tag4) {
   // expected-error@-1 {{cannot initialize return object of type 'int' with an rvalue of type 'char *'}}
   co_return; //expected-note {{function is a coroutine due to use of 'co_return' here}}
 }
@@ -1246,7 +1246,10 @@
   co_return;
 }
 
+struct some_class;
+
 struct good_promise_custom_constructor {
+  good_promise_custom_constructor(some_class&, float, int);
   good_promise_custom_constructor(double, float, int);
   good_promise_custom_constructor() = delete;
   coro<good_promise_custom_constructor> get_return_object();
@@ -1261,9 +1264,20 @@
   co_return;
 }
 
+struct some_class {
+  coro<good_promise_custom_constructor>
+  good_coroutine_calls_custom_constructor(float, int) {
+    co_return;
+  }
+  coro<good_promise_custom_constructor>
+  static good_coroutine_calls_custom_constructor(double, float, int) {
+    co_return;
+  }
+};
+
 struct bad_promise_no_matching_constructor {
   bad_promise_no_matching_constructor(int, int, int);
-  // expected-note@+1 {{'bad_promise_no_matching_constructor' has been explicitly marked deleted here}}
+  // expected-note@+1 2 {{'bad_promise_no_matching_constructor' has been explicitly marked deleted here}}
   bad_promise_no_matching_constructor() = delete;
   coro<bad_promise_no_matching_constructor> get_return_object();
   suspend_always initial_suspend();
@@ -1278,6 +1292,14 @@
   co_return;
 }
 
+struct some_class2 {
+coro<bad_promise_no_matching_constructor>
+bad_coroutine_calls_with_no_matching_constructor(int, int, int) {
+  // expected-error@-1 {{call to deleted constructor}}
+  co_return;
+}
+};
+
 } // namespace CoroHandleMemberFunctionTest
 
 class awaitable_no_unused_warn {