// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -std=c++20 -emit-llvm %s -o - -disable-llvm-passes | FileCheck %s

#include "Inputs/coroutine.h"

using namespace std;

namespace std {

struct nothrow_t {};
constexpr nothrow_t nothrow = {};

} // end namespace std

// Required when get_return_object_on_allocation_failure() is defined by
// the promise.
void* operator new(__SIZE_TYPE__ __sz, const std::nothrow_t&) noexcept;
void  operator delete(void* __p, const std::nothrow_t&) noexcept;


template <class RetObject>
struct promise_type {
    RetObject get_return_object();
    suspend_always initial_suspend();
    suspend_never final_suspend() noexcept;
    void return_void();
    static void unhandled_exception();
};

struct coro {
  using promise_type = promise_type<coro>;
  coro(coro const&);
  struct Impl;
  Impl *impl;
};

// Verify that the RVO is applied.
// CHECK-LABEL: define{{.*}} void @_Z1fi(ptr dead_on_unwind noalias writable sret(%struct.coro) align 8 %agg.result, i32 noundef %0)
coro f(int) {
// CHECK: %call = call noalias noundef nonnull ptr @_Znwm(
// CHECK-NEXT: br label %[[CoroInit:.*]]

// CHECK: {{.*}}[[CoroInit]]:
// CHECK: call void @{{.*get_return_objectEv}}(ptr dead_on_unwind writable sret(%struct.coro) align 8 %agg.result
co_return;
}


template <class RetObject>
struct promise_type_with_on_alloc_failure {
    static RetObject get_return_object_on_allocation_failure();
    RetObject get_return_object();
    suspend_always initial_suspend();
    suspend_never final_suspend() noexcept;
    void return_void();
    static void unhandled_exception();
};

struct coro_two {
  using promise_type = promise_type_with_on_alloc_failure<coro_two>;
  coro_two(coro_two const&);
  struct Impl;
  Impl *impl;
};

// Verify that the RVO is applied.
// CHECK-LABEL: define{{.*}} void @_Z1hi(ptr dead_on_unwind noalias writable sret(%struct.coro_two) align 8 %agg.result, i32 noundef %0)
coro_two h(int) {

  // CHECK: %call = call noalias noundef ptr @_ZnwmRKSt9nothrow_t
  // CHECK-NEXT: %[[CheckNull:.*]] = icmp ne ptr %call, null
  // CHECK-NEXT: br i1 %[[CheckNull]], label %[[InitOnSuccess:.*]], label %[[InitOnFailure:.*]]

  // CHECK: {{.*}}[[InitOnFailure]]:
  // CHECK-NEXT: call void @{{.*get_return_object_on_allocation_failureEv}}(ptr dead_on_unwind writable sret(%struct.coro_two) align 8 %agg.result
  // CHECK-NEXT: br label %[[RetLabel:.*]]

  // CHECK: {{.*}}[[InitOnSuccess]]:
  // CHECK: call void @{{.*get_return_objectEv}}(ptr dead_on_unwind writable sret(%struct.coro_two) align 8 %agg.result

  // CHECK: [[RetLabel]]:
  // CHECK-NEXT: ret void
  co_return;
}