1 files changed, 129 insertions, 0 deletions
diff --git a/neozip/arch/x86/chunkset_avx2.c b/neozip/arch/x86/chunkset_avx2.c
new file mode 100644
index 0000000000..3e69a7bf66
--- /dev/null
+++ b/neozip/arch/x86/chunkset_avx2.c
@@ -0,0 +1,129 @@
+/* chunkset_avx2.c -- AVX2 inline functions to copy small data chunks.
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+#ifdef X86_AVX2
+
+#include "zbuild.h"
+#include "zsanitizer.h"
+#include "zmemory.h"
+
+#include "arch/generic/chunk_256bit_perm_idx_lut.h"
+#include <immintrin.h>
+#include "x86_intrins.h"
+
+typedef __m256i chunk_t;
+typedef __m128i halfchunk_t;
+
+#define HAVE_CHUNKMEMSET_2
+#define HAVE_CHUNKMEMSET_4
+#define HAVE_CHUNKMEMSET_8
+#define HAVE_CHUNKMEMSET_16
+#define HAVE_CHUNK_MAG
+#define HAVE_HALF_CHUNK
+
+static inline void chunkmemset_2(uint8_t *from, chunk_t *chunk) {
+    *chunk = _mm256_set1_epi16(zng_memread_2(from));
+}
+
+static inline void chunkmemset_4(uint8_t *from, chunk_t *chunk) {
+    *chunk = _mm256_set1_epi32(zng_memread_4(from));
+}
+
+static inline void chunkmemset_8(uint8_t *from, chunk_t *chunk) {
+    *chunk = _mm256_set1_epi64x(zng_memread_8(from));
+}
+
+static inline void chunkmemset_16(uint8_t *from, chunk_t *chunk) {
+    /* See explanation in chunkset_avx512.c */
+#if defined(_MSC_VER) && _MSC_VER <= 1900
+    halfchunk_t half = _mm_loadu_si128((__m128i*)from);
+    *chunk = _mm256_inserti128_si256(_mm256_castsi128_si256(half), half, 1);
+#else
+    *chunk = _mm256_broadcastsi128_si256(_mm_loadu_si128((__m128i*)from));
+#endif
+}
+
+static inline void loadchunk(uint8_t const *s, chunk_t *chunk) {
+    *chunk = _mm256_loadu_si256((__m256i *)s);
+}
+
+static inline void storechunk(uint8_t *out, chunk_t *chunk) {
+    _mm256_storeu_si256((__m256i *)out, *chunk);
+}
+
+static inline chunk_t GET_CHUNK_MAG(uint8_t *buf, size_t *chunk_rem, size_t dist) {
+    lut_rem_pair lut_rem = perm_idx_lut[dist - 3];
+    __m256i ret_vec;
+    /* While technically we only need to read 4 or 8 bytes into this vector register for a lot of cases, GCC is
+     * compiling this to a shared load for all branches, preferring the simpler code.  Given that the buf value isn't in
+     * GPRs to begin with the 256 bit load is _probably_ just as inexpensive */
+    *chunk_rem = lut_rem.remval;
+
+    /* See note in chunkset_ssse3.c for why this is ok */
+    __msan_unpoison(buf + dist, 32 - dist);
+
+    if (dist < 16) {
+        /* This simpler case still requires us to shuffle in 128 bit lanes, so we must apply a static offset after
+         * broadcasting the first vector register to both halves. This is _marginally_ faster than doing two separate
+         * shuffles and combining the halves later */
+        __m256i perm_vec = _mm256_load_si256((__m256i*)(permute_table+lut_rem.idx));
+        __m128i ret_vec0 = _mm_loadu_si128((__m128i*)buf);
+        ret_vec = _mm256_inserti128_si256(_mm256_castsi128_si256(ret_vec0), ret_vec0, 1);
+        ret_vec = _mm256_shuffle_epi8(ret_vec, perm_vec);
+    }  else {
+        __m128i ret_vec0 = _mm_loadu_si128((__m128i*)buf);
+        __m128i ret_vec1 = _mm_loadu_si128((__m128i*)(buf + 16));
+        /* Take advantage of the fact that only the latter half of the 256 bit vector will actually differ */
+        __m128i perm_vec1 = _mm_load_si128((__m128i*)(permute_table + lut_rem.idx));
+        __m128i xlane_permutes = _mm_cmpgt_epi8(_mm_set1_epi8(16), perm_vec1);
+        __m128i xlane_res  = _mm_shuffle_epi8(ret_vec0, perm_vec1);
+        /* Since we can't wrap twice, we can simply keep the later half exactly how it is instead of having to _also_
+         * shuffle those values */
+        __m128i latter_half = _mm_blendv_epi8(ret_vec1, xlane_res, xlane_permutes);
+        ret_vec = _mm256_inserti128_si256(_mm256_castsi128_si256(ret_vec0), latter_half, 1);
+    }
+
+    return ret_vec;
+}
+
+static inline void loadhalfchunk(uint8_t const *s, halfchunk_t *chunk) {
+    *chunk = _mm_loadu_si128((__m128i *)s);
+}
+
+static inline void storehalfchunk(uint8_t *out, halfchunk_t *chunk) {
+    _mm_storeu_si128((__m128i *)out, *chunk);
+}
+
+static inline chunk_t halfchunk2whole(halfchunk_t *chunk) {
+    /* We zero extend mostly to appease some memory sanitizers. These bytes are ultimately
+     * unlikely to be actually written or read from */
+    return _mm256_zextsi128_si256(*chunk);
+}
+
+static inline halfchunk_t GET_HALFCHUNK_MAG(uint8_t *buf, size_t *chunk_rem, size_t dist) {
+    lut_rem_pair lut_rem = perm_idx_lut[dist - 3];
+    __m128i perm_vec, ret_vec;
+    __msan_unpoison(buf + dist, 16 - dist);
+    ret_vec = _mm_loadu_si128((__m128i*)buf);
+    *chunk_rem = half_rem_vals[dist - 3];
+
+    perm_vec = _mm_load_si128((__m128i*)(permute_table + lut_rem.idx));
+    ret_vec = _mm_shuffle_epi8(ret_vec, perm_vec);
+
+    return ret_vec;
+}
+
+#define CHUNKSIZE        chunksize_avx2
+#define CHUNKCOPY        chunkcopy_avx2
+#define CHUNKUNROLL      chunkunroll_avx2
+#define CHUNKMEMSET      chunkmemset_avx2
+#define CHUNKMEMSET_SAFE chunkmemset_safe_avx2
+
+#include "chunkset_tpl.h"
+
+#define INFLATE_FAST     inflate_fast_avx2
+
+#include "inffast_tpl.h"
+
+#endif