89ba7e183e
Fixes https://github.com/llvm/llvm-project/issues/63818 for control flow out of an expressions. #### Background A control flow could happen in the middle of an expression due to stmt-expr and coroutine suspensions. Due to branch-in-expr, we missed running cleanups for the temporaries constructed in the expression before the branch. Previously, these cleanups were only added as `EHCleanup` during the expression and as normal expression after the full expression. Examples of such deferred cleanups include: `ParenList/InitList`: Cleanups for fields are performed by the destructor of the object being constructed. `Array init`: Cleanup for elements of an array is included in the array cleanup. `Lifetime-extended temporaries`: reference-binding temporaries in braced-init are lifetime extended to the parent scope. `Lambda capture init`: init in the lambda capture list is destroyed by the lambda object. --- #### In this PR In this PR, we change some of the `EHCleanups` cleanups to `NormalAndEHCleanups` to make sure these are emitted when we see a branch inside an expression (through statement expressions or coroutine suspensions). These are supposed to be deactivated after full expression and destroyed later as part of the destructor of the aggregate or array being constructed. To simplify deactivating cleanups, we add two utilities as well: * `DeferredDeactivationCleanupStack`: A stack to remember cleanups with deferred deactivation. * `CleanupDeactivationScope`: RAII for deactivating cleanups added to the above stack. --- #### Deactivating normal cleanups These were previously `EHCleanups` and not `Normal` and **deactivation** of **required** `Normal` cleanups had some bugs. These specifically include deactivating `Normal` cleanups which are not the top of `EHStack` [source1](92b56011e6/clang/lib/CodeGen/CGCleanup.cpp (L1319)), [2](92b56011e6/clang/lib/CodeGen/CGCleanup.cpp (L722-L746)). This has not been part of our test suite (maybe it was never required before statement expressions). In this PR, we also fix the emission of required-deactivated-normal cleanups.
243 KiB
243 KiB