clang/test/CodeGenCoroutines/coro-lambda.cpp

   1 // Verify that we synthesized the coroutine for a lambda inside of a function template.
   2 // RUN: %clang_cc1 -std=c++20 -triple=x86_64-unknown-linux-gnu -emit-llvm -o - %s -fexceptions -fcxx-exceptions -disable-llvm-passes | FileCheck %s
   3
   4 namespace std {
   5 template <typename R, typename... T> struct coroutine_traits {
   6   using promise_type = typename R::promise_type;
   7 };
   8
   9 template <class Promise = void> struct coroutine_handle;
  10 template <> struct coroutine_handle<void> {
  11   static coroutine_handle from_address(void *) noexcept;
  12   coroutine_handle() = default;
  13   template <class PromiseType>
  14   coroutine_handle(coroutine_handle<PromiseType>) noexcept;
  15 };
  16 template <class Promise> struct coroutine_handle : coroutine_handle<void> {
  17   coroutine_handle() = default;
  18   static coroutine_handle from_address(void *) noexcept;
  19 };
  20 } // namespace std
  21
  22 struct suspend_always {
  23   bool await_ready() noexcept;
  24   void await_suspend(std::coroutine_handle<>) noexcept;
  25   void await_resume() noexcept;
  26 };
  27
  28 struct Task {
  29   struct promise_type {
  30     Task get_return_object();
  31     void return_void() {}
  32     suspend_always initial_suspend() noexcept;
  33     suspend_always final_suspend() noexcept;
  34     void unhandled_exception() noexcept;
  35   };
  36 };
  37
  38 template <typename _AwrT> auto SyncAwait(_AwrT &&A) {
  39   if (!A.await_ready()) {
  40     auto AwaitAsync = [&]() -> Task {
  41       try { (void)(co_await A); } catch (...) {}
  42     };
  43     Task t = AwaitAsync();
  44   }
  45   return A.await_resume();
  46 }
  47
  48 void f() {
  49   suspend_always test;
  50   SyncAwait(test);
  51 }
  52
  53 // Verify that we synthesized the coroutine for a lambda inside SyncAwait
  54 // CHECK-LABEL: define linkonce_odr void @_ZZ9SyncAwaitIR14suspend_alwaysEDaOT_ENKUlvE_clEv(
  55 //   CHECK: alloca %"struct.Task::promise_type"
  56 //   CHECK: call token @llvm.coro.id(
  57 //   CHECK: call i8 @llvm.coro.suspend(
  58 //   CHECK: call i1 @llvm.coro.end(