vppinfra: AArch64 NEON implementation of clib_compare_u16_x64()

[vpp.git] / src / vppinfra / vector_funcs.h

diff --git a/src/vppinfra/vector_funcs.h b/src/vppinfra/vector_funcs.h
index c867066..2b02d9e 100644 (file)
--- a/src/vppinfra/vector_funcs.h
+++ b/src/vppinfra/vector_funcs.h
@@ -17,7 +17,7 @@ static_always_inline u64
 clib_compare_u16_x64 (u16 v, u16 *a)
 {
   u64 mask = 0;
-#if defined(CLIB_HAVE_VEC512) && !defined(__aarch64__)
+#if defined(CLIB_HAVE_VEC512)
   u16x32 v32 = u16x32_splat (v);
   u16x32u *av = (u16x32u *) a;
   mask = ((u64) u16x32_is_equal_mask (av[0], v32) |
@@ -31,6 +31,25 @@ clib_compare_u16_x64 (u16 v, u16 *a)
   mask = i8x32_msb_mask ((i8x32) u64x4_permute (x, 0, 2, 1, 3));
   x = i16x16_pack (v16 == av[2], v16 == av[3]);
   mask |= (u64) i8x32_msb_mask ((i8x32) u64x4_permute (x, 0, 2, 1, 3)) << 32;
+#elif defined(CLIB_HAVE_VEC128) && defined(__ARM_NEON)
+  u16x8 idx8 = u16x8_splat (v);
+  u16x8 m = { 1, 2, 4, 8, 16, 32, 64, 128 };
+  u16x8u *av = (u16x8u *) a;
+
+  /* compare each u16 elemment with idx8, result gives 0xffff in each element
+     of the resulting vector if comparison result is true.
+     Bitwise AND with m will give us one bit set for true result and offset
+     of that bit represend element index. Finally vaddvq_u16() gives us sum
+     of all elements of the vector which will give us u8 bitmap. */
+
+  mask = ((u64) vaddvq_u16 ((av[0] == idx8) & m) |
+         (u64) vaddvq_u16 ((av[1] == idx8) & m) << 8 |
+         (u64) vaddvq_u16 ((av[2] == idx8) & m) << 16 |
+         (u64) vaddvq_u16 ((av[3] == idx8) & m) << 24 |
+         (u64) vaddvq_u16 ((av[4] == idx8) & m) << 32 |
+         (u64) vaddvq_u16 ((av[5] == idx8) & m) << 40 |
+         (u64) vaddvq_u16 ((av[6] == idx8) & m) << 48 |
+         (u64) vaddvq_u16 ((av[7] == idx8) & m) << 56);
 #elif defined(CLIB_HAVE_VEC128) && defined(CLIB_HAVE_VEC128_MSB_MASK)
   u16x8 idx8 = u16x8_splat (v);
   u16x8u *av = (u16x8u *) a;