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// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -std=c++20 \
// RUN: -O1 -emit-llvm %s -o - | FileCheck %s
#include "Inputs/coroutine.h"
// A simple awaiter type with an await_suspend method that can't be
// inlined.
struct Awaiter {
const int& x;
bool await_ready() { return false; }
std::coroutine_handle<> await_suspend(const std::coroutine_handle<> h);
void await_resume() {}
};
struct MyTask {
// A lazy promise with an await_transform method that supports awaiting
// integer references using the Awaiter struct above.
struct promise_type {
MyTask get_return_object() {
return MyTask{
std::coroutine_handle<promise_type>::from_promise(*this),
};
}
std::suspend_always initial_suspend() { return {}; }
std::suspend_always final_suspend() noexcept { return {}; }
void unhandled_exception();
auto await_transform(const int& x) { return Awaiter{x}; }
};
std::coroutine_handle<> h;
};
// A global array of integers.
int g_array[32];
// A coroutine that awaits each integer in the global array.
MyTask FooBar() {
for (const int& x : g_array) {
co_await x;
}
}
// CHECK: %[[RET:.+]] = {{.*}}call{{.*}}@_ZN7Awaiter13await_suspendESt16coroutine_handleIvE
// CHECK: %[[RESUME_ADDR:.+]] = load ptr, ptr %[[RET]],
// CHECK: musttail call fastcc void %[[RESUME_ADDR]]({{.*}}%[[RET]]
// CHECK: ret
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