1 files changed, 68 insertions, 0 deletions
diff --git a/neozip/arch/x86/slide_hash_sse2.c b/neozip/arch/x86/slide_hash_sse2.c
new file mode 100644
index 0000000000..4aa8df5ee8
--- /dev/null
+++ b/neozip/arch/x86/slide_hash_sse2.c
@@ -0,0 +1,68 @@
+/*
+ * SSE optimized hash slide
+ *
+ * Copyright (C) 2017 Intel Corporation
+ * Authors:
+ *   Arjan van de Ven   <arjan@linux.intel.com>
+ *   Jim Kukunas        <james.t.kukunas@linux.intel.com>
+ *
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+#ifdef X86_SSE2
+
+#include "zbuild.h"
+#include "deflate.h"
+
+#include <immintrin.h>
+#include <assert.h>
+
+static inline void slide_hash_chain(Pos *table0, Pos *table1, uint32_t entries0,
+                                    uint32_t entries1, const __m128i wsize) {
+    uint32_t entries;
+    Pos *table;
+    __m128i value0, value1, result0, result1;
+
+    int on_chain = 0;
+
+next_chain:
+    table = (on_chain) ? table1 : table0;
+    entries = (on_chain) ? entries1 : entries0;
+
+    table += entries;
+    table -= 16;
+
+    /* ZALLOC allocates this pointer unless the user chose a custom allocator.
+     * Our alloc function is aligned to 64 byte boundaries */
+    do {
+        value0 = _mm_load_si128((__m128i *)table);
+        value1 = _mm_load_si128((__m128i *)(table + 8));
+        result0 = _mm_subs_epu16(value0, wsize);
+        result1 = _mm_subs_epu16(value1, wsize);
+        _mm_store_si128((__m128i *)table, result0);
+        _mm_store_si128((__m128i *)(table + 8), result1);
+
+        table -= 16;
+        entries -= 16;
+    } while (entries > 0);
+
+    ++on_chain;
+    if (on_chain > 1) {
+        return;
+    } else {
+        goto next_chain;
+    }
+}
+
+Z_INTERNAL void slide_hash_sse2(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 __m128i xmm_wsize = _mm_set1_epi16((short)wsize);
+
+    assert(((uintptr_t)s->head & 15) == 0);
+    assert(((uintptr_t)s->prev & 15) == 0);
+
+    slide_hash_chain(s->head, s->prev, HASH_SIZE, wsize, xmm_wsize);
+}
+
+#endif