Commit Graph

3 Commits

Author SHA1 Message Date
Nikita Popov 3dd8c9176b [LICM] Remove AST-based implementation
MSSA-based LICM has been enabled by default for a few years now.
This drops the old AST-based implementation. Using loop(licm) will
result in a fatal error, the use of loop-mssa(licm) is required
(or just licm, which defaults to loop-mssa).

Note that the core canSinkOrHoistInst() logic has to retain AST
support for now, because it is shared with LoopSink.

Differential Revision: https://reviews.llvm.org/D108244
2021-08-18 20:21:53 +02:00
Max Kazantsev f8a42bca28 [ADCE] Fix incorrect reporting of CFG changes
This patch fixes 2 related bugs in ADCE:
- `performDeadCodeElimination` does not report changes if it did ONLY
  CFG changes (affects both old and new pass managers);
- When control flow removal is enabled, new pass manager does not
  drop CFG analyses.

Both can lead to incorrect loop info after ADCE that does only CFG changes.

Differential Revision: https://reviews.llvm.org/D78103
Reviewed By: Denis Antrushin
2020-04-14 20:26:13 +07:00
Max Kazantsev 2c4d914eeb [Test] Add failing test that demonstrates buggy behavior of ADCE
ADCE messes up with loop info (proved for new pass manager only) by
making some loop blocks unreachable, without making proper updates
to the loop.
2020-04-14 18:47:04 +07:00