From d51250f5e2bc99784399b196733e813fef000d71 Mon Sep 17 00:00:00 2001
From: Damjan Marion <damarion@cisco.com>
Date: Wed, 22 Dec 2021 12:22:59 +0100
Subject: [PATCH] vppinfra: add bihash 12_4 template

Type: feature
Change-Id: I8a6b2c7d7682a01c472d7375d444e8b43eb5db04
Signed-off-by: Damjan Marion <damarion@cisco.com>
---
 src/vppinfra/CMakeLists.txt |  1 +
 src/vppinfra/bihash_12_4.h  | 84 +++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 85 insertions(+)
 create mode 100644 src/vppinfra/bihash_12_4.h

diff --git a/src/vppinfra/CMakeLists.txt b/src/vppinfra/CMakeLists.txt
index 1a43f25b2c6..b08ebb61e6f 100644
--- a/src/vppinfra/CMakeLists.txt
+++ b/src/vppinfra/CMakeLists.txt
@@ -105,6 +105,7 @@ set(VPPINFRA_SRCS
 
 set(VPPINFRA_HEADERS
   sanitizer.h
+  bihash_12_4.h
   bihash_16_8.h
   bihash_24_8.h
   bihash_32_8.h
diff --git a/src/vppinfra/bihash_12_4.h b/src/vppinfra/bihash_12_4.h
new file mode 100644
index 00000000000..fe050e15924
--- /dev/null
+++ b/src/vppinfra/bihash_12_4.h
@@ -0,0 +1,84 @@
+/* SPDX-License-Identifier: Apache-2.0
+ * Copyright(c) 2021 Cisco Systems, Inc.
+ */
+#undef BIHASH_TYPE
+#undef BIHASH_KVP_PER_PAGE
+#undef BIHASH_32_64_SVM
+#undef BIHASH_ENABLE_STATS
+#undef BIHASH_KVP_AT_BUCKET_LEVEL
+#undef BIHASH_LAZY_INSTANTIATE
+#undef BIHASH_BUCKET_PREFETCH_CACHE_LINES
+#undef BIHASH_USE_HEAP
+
+#define BIHASH_TYPE			   _12_4
+#define BIHASH_KVP_PER_PAGE		   4
+#define BIHASH_KVP_AT_BUCKET_LEVEL	   0
+#define BIHASH_LAZY_INSTANTIATE		   1
+#define BIHASH_BUCKET_PREFETCH_CACHE_LINES 1
+#define BIHASH_USE_HEAP			   1
+
+#ifndef __included_bihash_12_4_h__
+#define __included_bihash_12_4_h__
+
+#include <vppinfra/crc32.h>
+#include <vppinfra/heap.h>
+#include <vppinfra/format.h>
+#include <vppinfra/pool.h>
+#include <vppinfra/xxhash.h>
+
+typedef union
+{
+  struct
+  {
+    u32 key[3];
+    u32 value;
+  };
+  u64 as_u64[2];
+} clib_bihash_kv_12_4_t;
+
+static inline int
+clib_bihash_is_free_12_4 (const clib_bihash_kv_12_4_t *v)
+{
+  /* Free values are clib_memset to 0xff, check a bit... */
+  if (v->as_u64[0] == ~0ULL && v->value == ~0)
+    return 1;
+  return 0;
+}
+
+static inline u64
+clib_bihash_hash_12_4 (const clib_bihash_kv_12_4_t *v)
+{
+#ifdef clib_crc32c_uses_intrinsics
+  return clib_crc32c ((u8 *) v->key, 12);
+#else
+  u64 tmp = v->as_u64[0] ^ v->key[2];
+  return clib_xxhash (tmp);
+#endif
+}
+
+static inline u8 *
+format_bihash_kvp_12_4 (u8 *s, va_list *args)
+{
+  clib_bihash_kv_12_4_t *v = va_arg (*args, clib_bihash_kv_12_4_t *);
+
+  s = format (s, "key %u %u %u value %u", v->key[0], v->key[1], v->key[2],
+	      v->value);
+  return s;
+}
+
+static inline int
+clib_bihash_key_compare_12_4 (u32 *a, u32 *b)
+{
+#if defined(CLIB_HAVE_VEC128)
+  u32x4 v = (*(u32x4u *) a) ^ (*(u32x4u *) b);
+  v[3] = 0;
+  return u32x4_is_all_zero (v);
+#else
+  return ((a[0] ^ b[0]) | (a[1] ^ b[1]) | (a[2] ^ b[2])) == 0;
+#endif
+}
+
+#undef __included_bihash_template_h__
+#include <vppinfra/bihash_template.h>
+
+#endif /* __included_bihash_12_4_h__ */
-- 
2.16.6