mirror of
https://github.com/RPCS3/llvm-mirror.git
synced 2024-11-23 03:02:36 +01:00
6de5f0f936
From C11 and C++11 onwards, a forward-progress requirement has been introduced for both languages. In the case of C, loops with non-constant conditionals that do not have any observable side-effects (as defined by 6.8.5p6) can be assumed by the implementation to terminate, and in the case of C++, this assumption extends to all functions. The clang frontend will emit the `mustprogress` function attribute for C++ functions (D86233, D85393, D86841) and emit the loop metadata `llvm.loop.mustprogress` for every loop in C11 or later that has a non-constant conditional. This patch modifies LoopDeletion so that only loops with the `llvm.loop.mustprogress` metadata or loops contained in functions that are required to make progress (`mustprogress` or `willreturn`) are checked for observable side-effects. If these loops do not have an observable side-effect, then we delete them. Loops without observable side-effects that do not satisfy the above conditions will not be deleted. Reviewed By: jdoerfert Differential Revision: https://reviews.llvm.org/D86844 |
||
---|---|---|
.. | ||
AggressiveInstCombine | ||
CFGuard | ||
Coroutines | ||
Hello | ||
HelloNew | ||
InstCombine | ||
Instrumentation | ||
IPO | ||
ObjCARC | ||
Scalar | ||
Utils | ||
Vectorize | ||
CMakeLists.txt |