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diff --git a/source/blender/blenlib/intern/hash_mm2a.c b/source/blender/blenlib/intern/hash_mm2a.c
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+++ b/source/blender/blenlib/intern/hash_mm2a.c
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+/*
+ * ***** BEGIN GPL LICENSE BLOCK *****
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * ***** END GPL LICENSE BLOCK *****
+ *
+ * Copyright (C) 2014 Blender Foundation.
+ *
+ */
+
+/** \file blender/blenlib/intern/hash_mm2a.c
+ *  \ingroup bli
+ *
+ *  Functions to compute Murmur2A hash key.
+ *
+ * A very fast hash generating int32 result, with few collisions and good repartition.
+ *
+ * See also:
+ *     reference implementation: https://smhasher.googlecode.com/svn-history/r130/trunk/MurmurHash2.cpp
+ *     and http://programmers.stackexchange.com/questions/49550/which-hashing-algorithm-is-best-for-uniqueness-and-speed
+ *
+ * \warning Do not store that hash in files or such, it is not endian-agnostic, so you should only use it
+ *          for temporary data.
+ */
+
+#include "BLI_hash_mm2a.h"  /* own include */
+
+/* Helpers. */
+#define MM2A_M 0x5bd1e995
+
+#define MM2A_MIX(h, k)           \
+{                                \
+	(k) *= MM2A_M;               \
+	(k) ^= (k) >> 24;            \
+	(k) *= MM2A_M;               \
+	(h) = ((h) * MM2A_M) ^ (k);  \
+} (void)0
+
+static void mm2a_mix_tail(BLI_HashMurmur2A *mm2, const unsigned char **data, size_t *len)
+{
+	while (*len && ((*len < 4) || mm2->count)) {
+		mm2->tail |= (uint32_t)(**data) << (mm2->count * 8);
+
+		mm2->count++;
+		(*len)--;
+		(*data)++;
+
+		if (mm2->count == 4) {
+			MM2A_MIX(mm2->hash, mm2->tail);
+			mm2->tail = 0;
+			mm2->count = 0;
+		}
+	}
+}
+
+void BLI_hash_mm2a_init(BLI_HashMurmur2A *mm2, uint32_t seed)
+{
+	mm2->hash  = seed;
+	mm2->tail  = 0;
+	mm2->count = 0;
+	mm2->size  = 0;
+}
+
+void BLI_hash_mm2a_add(BLI_HashMurmur2A *mm2, const unsigned char *data, size_t len)
+{
+	mm2->size += (uint32_t)len;
+
+	mm2a_mix_tail(mm2, &data, &len);
+
+	for (; len >= 4; data += 4, len -= 4) {
+		uint32_t k = *(const uint32_t *)data;
+
+		MM2A_MIX(mm2->hash, k);
+	}
+
+	mm2a_mix_tail(mm2, &data, &len);
+}
+
+void BLI_hash_mm2a_add_int(BLI_HashMurmur2A *mm2, int data)
+{
+	BLI_hash_mm2a_add(mm2, (const unsigned char *)&data, sizeof(data));
+}
+
+uint32_t BLI_hash_mm2a_end(BLI_HashMurmur2A *mm2)
+{
+	MM2A_MIX(mm2->hash, mm2->tail);
+	MM2A_MIX(mm2->hash, mm2->size);
+
+	mm2->hash ^= mm2->hash >> 13;
+	mm2->hash *= MM2A_M;
+	mm2->hash ^= mm2->hash >> 15;
+
+	return mm2->hash;
+}