+ /**
+ * Calculate the sum and difference of two vectors of floats and interleave
+ * results into a separate output vector of floats, with each sum
+ * positioned before the corresponding difference.
+ *
+ * @param dst output vector
+ * constraints: 16-byte aligned
+ * @param src0 first input vector
+ * constraints: 32-byte aligned
+ * @param src1 second input vector
+ * constraints: 32-byte aligned
+ * @param len number of elements in the input
+ * constraints: multiple of 8
+ */
+ void (*butterflies_float_interleave)(float *dst, const float *src0,
+ const float *src1, int len);
+