1 files changed, 78 insertions, 0 deletions
diff --git a/src/vppinfra/vector/compress.h b/src/vppinfra/vector/compress.h
new file mode 100644
index 00000000000..1d5d84e77ea
--- /dev/null
+++ b/src/vppinfra/vector/compress.h
@@ -0,0 +1,78 @@
+/* SPDX-License-Identifier: Apache-2.0
+ * Copyright(c) 2021 Cisco Systems, Inc.
+ */
+
+#ifndef included_vector_compress_h
+#define included_vector_compress_h
+#include <vppinfra/clib.h>
+#include <vppinfra/memcpy.h>
+
+static_always_inline u32 *
+clib_compress_u32_x64 (u32 *dst, u32 *src, u64 mask)
+{
+#if defined(CLIB_HAVE_VEC512_COMPRESS)
+  u32x16u *sv = (u32x16u *) src;
+  for (int i = 0; i < 4; i++)
+    {
+      int cnt = _popcnt32 ((u16) mask);
+      u32x16_compress_store (sv[i], mask, dst);
+      dst += cnt;
+      mask >>= 16;
+    }
+
+#elif defined(CLIB_HAVE_VEC256_COMPRESS)
+  u32x8u *sv = (u32x8u *) src;
+  for (int i = 0; i < 8; i++)
+    {
+      int cnt = _popcnt32 ((u8) mask);
+      u32x8_compress_store (sv[i], mask, dst);
+      dst += cnt;
+      mask >>= 8;
+    }
+#else
+  while (mask)
+    {
+      u16 bit = count_trailing_zeros (mask);
+      mask = clear_lowest_set_bit (mask);
+      dst++[0] = src[bit];
+    }
+#endif
+  return dst;
+}
+
+/** \brief Compress array of 32-bit elemments into destination array based on
+ * mask
+
+    @param dst destination array of u32 elements
+    @param src source array of u32 elements
+    @param mask array of u64 values representing compress mask
+    @param n_elts number of elements in the source array
+    @return number of elements stored in destionation array
+*/
+
+static_always_inline u32
+clib_compress_u32 (u32 *dst, u32 *src, u64 *mask, u32 n_elts)
+{
+  u32 *dst0 = dst;
+  while (n_elts >= 64)
+    {
+      if (mask[0] == ~0ULL)
+	{
+	  clib_memcpy_u32 (dst, src, 64);
+	  dst += 64;
+	}
+      else
+	dst = clib_compress_u32_x64 (dst, src, mask[0]);
+
+      mask++;
+      src += 64;
+      n_elts -= 64;
+    }
+
+  if (PREDICT_TRUE (n_elts == 0))
+    return dst - dst0;
+
+  return clib_compress_u32_x64 (dst, src, mask[0] & pow2_mask (n_elts)) - dst0;
+}
+
+#endif