Files
clang-p2996/llvm/lib/Transforms/Scalar/LoopInterchange.cpp
Ta-Wei Tu df9158c9a4 [LoopInterchange] Replace tightly-nesting-ness check with the one from LoopNest
The check `tightlyNested()` in `LoopInterchange` is similar to the one in `LoopNest`.
In fact, the former misses some cases where loop-interchange is not feasible and results in incorrect behaviour.
Replacing it with the much robust version provided by `LoopNest` reduces code duplications and fixes https://bugs.llvm.org/show_bug.cgi?id=48113.

`LoopInterchange` has a weaker definition of tightly or perfectly nesting-ness than the one implemented in `LoopNest::arePerfectlyNested()`.
Therefore, `tightlyNested()` is instead implemented with `LoopNest::checkLoopsStructure` and additional checks for unsafe instructions.

Reviewed By: Whitney

Differential Revision: https://reviews.llvm.org/D97290
2021-03-08 11:36:08 +08:00

63 KiB