diff options
| author | Julian Nagele <j.nagele@apple.com> | 2024-11-15 10:03:08 +0000 |
|---|---|---|
| committer | GitHub <noreply@github.com> | 2024-11-15 10:03:08 +0000 |
| commit | 7c8e05aa45f006401b71b37127537c4682fe16ee (patch) | |
| tree | 09d92eec749187604be4c7be708b0156e87e35ee /llvm/lib/Target/WebAssembly/Disassembler/WebAssemblyDisassembler.cpp | |
| parent | e5ac9145ba2951b6454b13499f375284bdbde689 (diff) | |
| download | llvm-7c8e05aa45f006401b71b37127537c4682fe16ee.zip llvm-7c8e05aa45f006401b71b37127537c4682fe16ee.tar.gz llvm-7c8e05aa45f006401b71b37127537c4682fe16ee.tar.bz2 | |
[SCEV] Collect and merge loop guards through PHI nodes with multiple incoming values (#113915)
This patch aims to strengthen collection of loop guards by processing
PHI nodes with multiple incoming values as follows: collect guards for
all incoming values/blocks and try to merge them into a single one for
the PHI node.
The goal is to determine tighter bounds on the trip counts of scalar
tail loops after vectorization, helping to avoid unnecessary transforms.
In particular we'd like to avoid vectorizing scalar tails of
hand-vectorized loops, for example in
[Transforms/PhaseOrdering/X86/pr38280.ll](https://github.com/llvm/llvm-project/blob/231e03ba7e82896847dbc27d457dbb208f04699c/llvm/test/Transforms/PhaseOrdering/X86/pr38280.ll),
discovered via https://github.com/llvm/llvm-project/pull/108190
Compile-time impact: https://llvm-compile-time-tracker.com/compare.php?from=a55248789ed3f653740e0723d016203b9d585f26&to=500e4c46e79f60b93b11a752698c520e345948e3&stat=instructions:u
PR: https://github.com/llvm/llvm-project/pull/113915
Diffstat (limited to 'llvm/lib/Target/WebAssembly/Disassembler/WebAssemblyDisassembler.cpp')
0 files changed, 0 insertions, 0 deletions