Use AVX2 on x86_64 architectures only

recipe/meta.yaml

@@ -112,8 +112,9 @@ outputs:
       commands:
         - exit 0
 
-  # build two separate C++ libs, one for generic x64, and one for AVX2
-  {% for CF_FAISS_BUILD in ["avx2", "generic"] %}
+  # build two separate C++ libs, one generic, and one for AVX2 on x86_64
+  {% for CF_FAISS_BUILD in ["generic"] %}          # [arm64 or aarch64]
+  {% for CF_FAISS_BUILD in ["avx2", "generic"] %}  # [x86_64]
   # order libfaiss last in loop due to conda/conda-build#4090; libfaiss-avx2
   # is only used for faiss and not important enough to work-around for this bug
   {% if CF_FAISS_BUILD == "generic" %}
@@ -191,13 +192,13 @@ outputs:
         - pip
         - numpy
         - libfaiss ={{ version }}=*_{{ faiss_proc_type }}
-        - libfaiss-avx2 ={{ version }}=*_{{ faiss_proc_type }}
+        - libfaiss-avx2 ={{ version }}=*_{{ faiss_proc_type }}  # [x86_64]
         - libblas
         - liblapack
       run:
         - python
         - libfaiss ={{ version }}=*_{{ faiss_proc_type }}
-        - libfaiss-avx2 ={{ version }}=*_{{ faiss_proc_type }}
+        - libfaiss-avx2 ={{ version }}=*_{{ faiss_proc_type }}  # [x86_64]
         - {{ pin_compatible('numpy') }}
       run_constrained:
         - faiss-cpu ==9999999999  # [cuda_compiler_version != "None"]
@@ -223,7 +224,7 @@ outputs:
         # the linux & windows CI agents support AVX2 (OSX doesn't yet), so by default,
         # we expect faiss will load the library with AVX2-support, see
         # https://github.com/facebookresearch/faiss/blob/v1.7.1/faiss/python/loader.py#L52-L66
-        - export HAS_AVX2=YES && ./test-pkg.sh  # [linux]
+        - export HAS_AVX2=YES && ./test-pkg.sh  # [linux64]
         - export HAS_AVX2=NO  && ./test-pkg.sh  # [osx]
         # skip test suite on win + cuda < 11.2 due to time outs (note: "None" >= "11.2")
         {% if cuda_compiler_version|string >= "11.2" %}