Don't test x86_64 simd on archs other than x86_64
Don't test x86_64 simd on archs other than x86_64

aidancully/rust,aidancully/rust,aidancully/rust,aidancully/rust,graydon/rust,graydon/rust,graydon/rust,graydon/rust,graydon/rust,aidancully/rust,graydon/rust,aidancully/rust