1 files changed, 48 insertions, 0 deletions
diff --git a/neozip/arch/x86/slide_hash_avx2.c b/neozip/arch/x86/slide_hash_avx2.c
new file mode 100644
index 0000000000..241ea305e3
--- /dev/null
+++ b/neozip/arch/x86/slide_hash_avx2.c
@@ -0,0 +1,48 @@
+/*
+ * AVX2 optimized hash slide, based on Intel's slide_sse implementation
+ *
+ * Copyright (C) 2017 Intel Corporation
+ * Authors:
+ *   Arjan van de Ven   <arjan@linux.intel.com>
+ *   Jim Kukunas        <james.t.kukunas@linux.intel.com>
+ *   Mika T. Lindqvist  <postmaster@raasu.org>
+ *
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+#ifdef X86_AVX2
+
+#include "zbuild.h"
+#include "deflate.h"
+
+#include <immintrin.h>
+
+static inline void slide_hash_chain(Pos *table, uint32_t entries, const __m256i wsize) {
+    table += entries;
+    table -= 32;
+
+    do {
+        __m256i value1, value2, result1, result2;
+
+        value1 = _mm256_load_si256((__m256i *)table);
+        value2 = _mm256_load_si256((__m256i *)(table+16));
+        result1 = _mm256_subs_epu16(value1, wsize);
+        result2 = _mm256_subs_epu16(value2, wsize);
+        _mm256_store_si256((__m256i *)table, result1);
+        _mm256_store_si256((__m256i *)(table+16), result2);
+
+        table -= 32;
+        entries -= 32;
+    } while (entries > 0);
+}
+
+Z_INTERNAL void slide_hash_avx2(deflate_state *s) {
+    Assert(s->w_size <= UINT16_MAX, "w_size should fit in uint16_t");
+    uint16_t wsize = (uint16_t)s->w_size;
+    const __m256i ymm_wsize = _mm256_set1_epi16((short)wsize);
+
+    slide_hash_chain(s->head, HASH_SIZE, ymm_wsize);
+    slide_hash_chain(s->prev, wsize, ymm_wsize);
+}
+
+#endif