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| author | Roman Lebedev <lebedev.ri@gmail.com> | 2021-05-13 23:54:11 +0300 |
|---|---|---|
| committer | Roman Lebedev <lebedev.ri@gmail.com> | 2021-05-14 00:03:36 +0300 |
| commit | aa0dcb3ba4b93e4499208def080ced98f3a89ad5 (patch) | |
| tree | 5f049ea65cdee34947a02c4a1dec693b5d60c214 /llvm/lib/Bitcode/Writer/BitcodeWriter.cpp | |
| parent | 6c4596793d43703923552e791716a3d511e28fe0 (diff) | |
[X86] AMD Zen 3: same-reg SSE XMM XORPS is a 1-cycle(!) dep-breaking one-idiom
While both the SOG and Agner insist that it is zero-cycle,
i can not confirm that claim. While it clearly breaks the dependency,
i can not come up with a snippet, or measurement approach,
to end up with IPC bigger than 4, which, to me, means that it actually
consumes execution resource of an FP unit for a cycle.
Diffstat (limited to 'llvm/lib/Bitcode/Writer/BitcodeWriter.cpp')
0 files changed, 0 insertions, 0 deletions