define NNlib.leakyrelu(::AbstractSIMD) for Julia 1.6 test

Author: chriselrod

test/forwarddiffext.jl

@@ -15,6 +15,11 @@ function tovec(x::ForwardDiff.Dual{T,V,N}) where {T,V,N}
   return ret
 end
 
+if LoopVectorization.ifelse !== Base.ifelse
+  @inline function NNlib.leakyrelu(x::LoopVectorization.AbstractSIMD, a=NNlib.oftf(x, NNlib.leakyrelu_a)) 
+     LoopVectorization.ifelse(x>0, float(x), NNlib.oftf(x, a*x))  # max(a*x, x) is 3x slower
+  end
+end
 
 vx0 = randnvec()
 vx1 = randnvec()