add simd evalpoly

Co-authored-by: @oscardssmith


Actually get right branch information

Author: heltonmc

src/misc.jl

@@ -44,4 +44,18 @@ end
     w  = fn * 6.07710050650619224932e-11
     y = r-w
     return unsafe_trunc(Int, fn), Base.Math.DoubleFloat64(y, (r-y)-w)
-end
+end
+
+function simd_evalpoly_width4(μ, ps::NTuple{N, NTuple{4, T}}) where {N, T}
+    s1 = ps[N][1]
+    s2 = ps[N][2]
+    s3 = ps[N][3]
+    s4 = ps[N][4]
+    @inbounds for i in N-1:-1:1
+        s1 = muladd(μ, s1, ps[i][1])
+        s2 = muladd(μ, s2, ps[i][2])
+        s3 = muladd(μ, s3, ps[i][3])
+        s4 = muladd(μ, s2, ps[i][4])
+    end
+    return (s1, s2, s3, s4)
+end