From d9961cf6e7f5e99b14fae1f2b7fb00fa62bc8c62 Mon Sep 17 00:00:00 2001
From: "1091761+wx257osn2@users.noreply.github.com"
 <1091761+wx257osn2@users.noreply.github.com>
Date: Wed, 31 Aug 2022 05:45:17 -0700
Subject: [PATCH] Remove an Outdated Description in INSTALL.md (#2391)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and confirmed that (current `faiss` treats `sse4` as same as `generic`), so this PR removes the description of this outdated option from `INSTALL.md` .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: https://github.com/facebookresearch/faiss/pull/2391

Reviewed By: alexanderguzhva

Differential Revision: D39167022

Pulled By: mdouze

fbshipit-source-id: ff36fc5167c4d2e8d16206061624a8ba2890b4b7
---
 INSTALL.md | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/INSTALL.md b/INSTALL.md
index e7ddc9559..9d928a4ea 100644
--- 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