| // Test the behavior of http://wg21.link/P0664, a proposal to catch any |
| // exceptions thrown after the initial suspend point of a coroutine by |
| // executing the handler specified by the promise type's 'unhandled_exception' |
| // member function. |
| // |
| // RUN: %clang_cc1 -std=c++14 -fcoroutines-ts \ |
| // RUN: -triple=x86_64-unknown-linux-gnu -emit-llvm -o - %s \ |
| // RUN: -fexceptions -fcxx-exceptions -disable-llvm-passes \ |
| // RUN: | FileCheck %s |
| |
| #include "Inputs/coroutine.h" |
| |
| namespace coro = std::experimental::coroutines_v1; |
| |
| struct throwing_awaitable { |
| bool await_ready() { return true; } |
| void await_suspend(coro::coroutine_handle<>) {} |
| void await_resume() { throw 42; } |
| }; |
| |
| struct throwing_task { |
| struct promise_type { |
| auto get_return_object() { return throwing_task{}; } |
| auto initial_suspend() { return throwing_awaitable{}; } |
| auto final_suspend() noexcept { return coro::suspend_never{}; } |
| void return_void() {} |
| void unhandled_exception() {} |
| }; |
| }; |
| |
| // CHECK-LABEL: define void @_Z1fv() |
| throwing_task f() { |
| // A variable RESUMETHREW is used to keep track of whether the body |
| // of 'await_resume' threw an exception. Exceptions thrown in |
| // 'await_resume' are unwound to RESUMELPAD. |
| // CHECK: init.ready: |
| // CHECK-NEXT: store i1 true, i1* %[[RESUMETHREW:.+]], align 1 |
| // CHECK-NEXT: invoke void @_ZN18throwing_awaitable12await_resumeEv |
| // CHECK-NEXT: to label %[[RESUMECONT:.+]] unwind label %[[RESUMELPAD:.+]] |
| |
| // If 'await_resume' does not throw an exception, 'false' is stored in |
| // variable RESUMETHREW. |
| // CHECK: [[RESUMECONT]]: |
| // CHECK-NEXT: store i1 false, i1* %[[RESUMETHREW]] |
| // CHECK-NEXT: br label %[[RESUMETRYCONT:.+]] |
| |
| // 'unhandled_exception' is called for the exception thrown in |
| // 'await_resume'. The variable RESUMETHREW is never set to false, |
| // and a jump is made to RESUMETRYCONT. |
| // CHECK: [[RESUMELPAD]]: |
| // CHECK: br label %[[RESUMECATCH:.+]] |
| // CHECK: [[RESUMECATCH]]: |
| // CHECK: invoke void @_ZN13throwing_task12promise_type19unhandled_exceptionEv |
| // CHECK-NEXT: to label %[[RESUMEENDCATCH:.+]] unwind label |
| // CHECK: [[RESUMEENDCATCH]]: |
| // CHECK-NEXT: invoke void @__cxa_end_catch() |
| // CHECK-NEXT: to label %[[RESUMEENDCATCHCONT:.+]] unwind label |
| // CHECK: [[RESUMEENDCATCHCONT]]: |
| // CHECK-NEXT: br label %[[RESUMETRYCONT]] |
| |
| // The variable RESUMETHREW is loaded and if true, then 'await_resume' |
| // threw an exception and the coroutine body is skipped, and the final |
| // suspend is executed immediately. Otherwise, the coroutine body is |
| // executed, and then the final suspend. |
| // CHECK: [[RESUMETRYCONT]]: |
| // CHECK-NEXT: %[[RESUMETHREWLOAD:.+]] = load i1, i1* %[[RESUMETHREW]] |
| // CHECK-NEXT: br i1 %[[RESUMETHREWLOAD]], label %[[RESUMEDCONT:.+]], label %[[RESUMEDBODY:.+]] |
| |
| // CHECK: [[RESUMEDBODY]]: |
| // CHECK: invoke void @_ZN13throwing_task12promise_type11return_voidEv |
| // CHECK-NEXT: to label %[[REDUMEDBODYCONT:.+]] unwind label |
| // CHECK: [[REDUMEDBODYCONT]]: |
| // CHECK-NEXT: br label %[[COROFINAL:.+]] |
| |
| // CHECK: [[RESUMEDCONT]]: |
| // CHECK-NEXT: br label %[[COROFINAL]] |
| |
| // CHECK: [[COROFINAL]]: |
| // CHECK-NEXT: call void @_ZN13throwing_task12promise_type13final_suspendEv |
| co_return; |
| } |
| |
| struct noexcept_awaitable { |
| bool await_ready() { return true; } |
| void await_suspend(coro::coroutine_handle<>) {} |
| void await_resume() noexcept {} |
| }; |
| |
| struct noexcept_task { |
| struct promise_type { |
| auto get_return_object() { return noexcept_task{}; } |
| auto initial_suspend() { return noexcept_awaitable{}; } |
| auto final_suspend() noexcept { return coro::suspend_never{}; } |
| void return_void() {} |
| void unhandled_exception() {} |
| }; |
| }; |
| |
| // CHECK-LABEL: define void @_Z1gv() |
| noexcept_task g() { |
| // If the await_resume function is marked as noexcept, none of the additional |
| // conditions that are present in f() above are added to the IR. |
| // This means that no i1 are stored before or after calling await_resume: |
| // CHECK: init.ready: |
| // CHECK-NEXT: call void @_ZN18noexcept_awaitable12await_resumeEv |
| // CHECK-NOT: store i1 false, i1* |
| co_return; |
| } |