Remove an Outdated Description in INSTALL.md (#2391)

Summary: According to [`CMakeLists.txt`](https://github.com/facebookresearch/faiss/blob/442d9f4a2d43e2ada6423e8e4e3414131dea849d/CMakeLists.txt#L20), current `faiss` doesn't recognize `sse4` as `FAISS_OPT_LEVEL` . I've read `CMakeLists.txt`s and confirmed that (current `faiss` treats `sse4` as same as `generic`), so this PR removes the description of this outdated option from `INSTALL.md` . This PR contains only document update, so this doesn't affect the software behavior. Pull Request resolved: #2391 Reviewed By: alexanderguzhva Differential Revision: D39167022 Pulled By: mdouze fbshipit-source-id: ff36fc5167c4d2e8d16206061624a8ba2890b4b7
facebookresearch · Aug 31, 2022 · d9961cf · d9961cf
1 parent f07e82a
commit d9961cf
Showing 1 changed file with 2 additions and 2 deletions.
diff --git a/INSTALL.md b/INSTALL.md
@@ -101,8 +101,8 @@ Several options can be passed to CMake, among which:
   - `-DCMAKE_BUILD_TYPE=Release` in order to enable generic compiler
   optimization options (enables `-O3` on gcc for instance),
   - `-DFAISS_OPT_LEVEL=avx2` in order to enable the required compiler flags to
-  generate code using optimized SIMD instructions (possible values are `generic`,
-  `sse4`, and `avx2`, by increasing order of optimization),
+  generate code using optimized SIMD instructions (possible values are `generic`
+  and `avx2`, by increasing order of optimization),
 - BLAS-related options:
   - `-DBLA_VENDOR=Intel10_64_dyn -DMKL_LIBRARIES=/path/to/mkl/libs` to use the
   Intel MKL BLAS implementation, which is significantly faster than OpenBLAS