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From 91c1e78feec94739cc5da8562b3e2395bfdf6193 Mon Sep 17 00:00:00 2001
From: hedongbo <hedongbo@huawei.com>
Date: Sun, 14 Sep 2020 15:36:12 +0800
Subject: [PATCH] zlib-1.2.11-SIMD.patch

In the sampling of the Hive test program, it is found that inflate occupies a high proportion.
The zlib is optimized through instruction set optimization, hash replacement, and compilation option optimization. 
The inflate and deflate processes of the Zlib library provided by the JDK are optimized to shorten the invoking time.
---
 CMakeLists.txt |   6 +
 adler32.c      | 169 +++++++++++++++++++++-
 deflate.c      |  22 ++-
 inffast.c      |  62 ++++++++-
 inffast.h      | 370 +++++++++++++++++++++++++++++++++++++++++++++++++
 inflate.c      |   7 +
 6 files changed, 627 insertions(+), 9 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index b412dc7..40dc533 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -126,6 +126,12 @@ if(NOT MINGW)
     )
 endif()
 
+if(CMAKE_COMPILER_IS_GNUCC)
+    if(ARM_NEON)
+         add_definitions(-DHASH_ARMV8_CRC32 -march=armv8-a+crc -DUNALIGNED_OK -DADLER32_SIMD_NEON -DINFLATE_CHUNK_SIMD_NEON -O3)
+    endif()
+endif()
+
 # parse the full version number from zlib.h and include in ZLIB_FULL_VERSION
 file(READ ${CMAKE_CURRENT_SOURCE_DIR}/zlib.h _zlib_h_contents)
 string(REGEX REPLACE ".*#define[ \t]+ZLIB_VERSION[ \t]+\"([-0-9A-Za-z.]+)\".*"
diff --git a/adler32.c b/adler32.c
index d0be438..6ced75d 100644
--- a/adler32.c
+++ b/adler32.c
@@ -59,7 +59,169 @@ local uLong adler32_combine_ OF((uLong adler1, uLong adler2, z_off64_t len2));
 #  define MOD63(a) a %= BASE
 #endif
 
-/* ========================================================================= */
+#if defined(ADLER32_SIMD_NEON)
+#include <arm_neon.h>
+/*
+ * Multiply-add bytes by [ 32, 31, 30, ... ] for s2.
+ */
+uint32x4_t ZLIB_INTERNAL mul_add_bytes(
+    uint32x4_t v_s2,
+    uint16x8_t v_column_sum_1,
+    uint16x8_t v_column_sum_2,
+    uint16x8_t v_column_sum_3,
+    uint16x8_t v_column_sum_4)
+{
+    v_s2 = vshlq_n_u32(v_s2, 5);
+
+    v_s2 = vmlal_u16(v_s2, vget_low_u16 (v_column_sum_1),
+        (uint16x4_t) { 32, 31, 30, 29 });
+    v_s2 = vmlal_u16(v_s2, vget_high_u16(v_column_sum_1),
+        (uint16x4_t) { 28, 27, 26, 25 });
+    v_s2 = vmlal_u16(v_s2, vget_low_u16 (v_column_sum_2),
+        (uint16x4_t) { 24, 23, 22, 21 });
+    v_s2 = vmlal_u16(v_s2, vget_high_u16(v_column_sum_2),
+        (uint16x4_t) { 20, 19, 18, 17 });
+    v_s2 = vmlal_u16(v_s2, vget_low_u16 (v_column_sum_3),
+        (uint16x4_t) { 16, 15, 14, 13 });
+    v_s2 = vmlal_u16(v_s2, vget_high_u16(v_column_sum_3),
+        (uint16x4_t) { 12, 11, 10,  9 });
+    v_s2 = vmlal_u16(v_s2, vget_low_u16 (v_column_sum_4),
+        (uint16x4_t) {  8,  7,  6,  5 });
+    v_s2 = vmlal_u16(v_s2, vget_high_u16(v_column_sum_4),
+        (uint16x4_t) {  4,  3,  2,  1 });
+    return v_s2;
+}
+
+/*
+ * Handle leftover data.
+ */
+uLong ZLIB_INTERNAL leftover_handler(uint32_t s1, uint32_t s2, const Bytef *buf, z_size_t len)
+{
+    if (len) {
+        if (len >= 16) {
+            s2 += (s1 += *buf++);
+            s2 += (s1 += *buf++);
+            s2 += (s1 += *buf++);
+            s2 += (s1 += *buf++);
+
+            s2 += (s1 += *buf++);
+            s2 += (s1 += *buf++);
+            s2 += (s1 += *buf++);
+            s2 += (s1 += *buf++);
+
+            s2 += (s1 += *buf++);
+            s2 += (s1 += *buf++);
+            s2 += (s1 += *buf++);
+            s2 += (s1 += *buf++);
+
+            s2 += (s1 += *buf++);
+            s2 += (s1 += *buf++);
+            s2 += (s1 += *buf++);
+            s2 += (s1 += *buf++);
+
+            len -= 16;
+        }
+
+        while (len--) {
+            s2 += (s1 += *buf++);
+        }
+
+        if (s1 >= BASE)
+            s1 -= BASE;
+        s2 %= BASE;
+    }
+
+    /*
+     * Return the recombined sums.
+     */
+    return s1 | (s2 << 16);
+}
+
+uLong ZLIB_INTERNAL adler32_simd_(uLong adler, const Bytef *buf, z_size_t len)
+{
+    /*
+     * Split Adler-32 into component sums.
+     */
+    uint32_t s1 = adler & 0xffff;
+    uint32_t s2 = adler >> 16;
+    /*
+     * Serially compute s1 & s2, until the data is 16-byte aligned.
+     */
+    if ((uintptr_t)buf & 0xf) {
+        while ((uintptr_t)buf & 0xf) {
+            s2 += (s1 += *buf++);
+            --len;
+        }
+        if (s1 >= BASE)
+            s1 -= BASE;
+        s2 %= BASE;
+    }
+    /*
+     * Process the data in blocks.
+     */
+    const unsigned BLOCK_SIZE = 1 << 5;
+    z_size_t blocks = len / BLOCK_SIZE;
+    len -= blocks * BLOCK_SIZE;
+    while (blocks) {
+        unsigned n = NMAX / BLOCK_SIZE;  /* The NMAX constraint. */
+        if (n > blocks)
+            n = (unsigned) blocks;
+        blocks -= n;
+        /*
+         * Process n blocks of data. At most NMAX data bytes can be
+         * processed before s2 must be reduced modulo BASE.
+         */
+        uint32x4_t v_s2 = (uint32x4_t) { 0, 0, 0, s1 * n };
+        uint32x4_t v_s1 = (uint32x4_t) { 0, 0, 0, 0 };
+
+        uint16x8_t v_column_sum_1 = vdupq_n_u16(0);
+        uint16x8_t v_column_sum_2 = vdupq_n_u16(0);
+        uint16x8_t v_column_sum_3 = vdupq_n_u16(0);
+        uint16x8_t v_column_sum_4 = vdupq_n_u16(0);
+        do {
+            /*
+             * Load 32 input bytes.
+             */
+            const uint8x16_t bytes1 = vld1q_u8((uint8_t*)(buf));
+            const uint8x16_t bytes2 = vld1q_u8((uint8_t*)(buf + 16));
+            /*
+             * Add previous block byte sum to v_s2.
+             */
+            v_s2 = vaddq_u32(v_s2, v_s1);
+            /*
+             * Horizontally add the bytes for s1.
+             */
+            v_s1 = vpadalq_u16(v_s1, vpadalq_u8(vpaddlq_u8(bytes1), bytes2));
+            /*
+             * Vertically add the bytes for s2.
+             */
+            v_column_sum_1 = vaddw_u8(v_column_sum_1, vget_low_u8 (bytes1));
+            v_column_sum_2 = vaddw_u8(v_column_sum_2, vget_high_u8(bytes1));
+            v_column_sum_3 = vaddw_u8(v_column_sum_3, vget_low_u8 (bytes2));
+            v_column_sum_4 = vaddw_u8(v_column_sum_4, vget_high_u8(bytes2));
+            buf += BLOCK_SIZE;
+        } while (--n);
+        v_s2 = mul_add_bytes(v_s2, v_column_sum_1, v_column_sum_2, v_column_sum_3, v_column_sum_4);
+        /*
+         * Sum epi32 ints v_s1(s2) and accumulate in s1(s2).
+         */
+        uint32x2_t sum1 = vpadd_u32(vget_low_u32(v_s1), vget_high_u32(v_s1));
+        uint32x2_t sum2 = vpadd_u32(vget_low_u32(v_s2), vget_high_u32(v_s2));
+        uint32x2_t s1s2 = vpadd_u32(sum1, sum2);
+
+        s1 += vget_lane_u32(s1s2, 0);
+        s2 += vget_lane_u32(s1s2, 1);
+        /*
+         * Reduce.
+         */
+        s1 %= BASE;
+        s2 %= BASE;
+    }
+    return leftover_handler(s1, s2, buf, len);
+
+}
+#endif
+
 uLong ZEXPORT adler32_z(uLong adler, const Bytef *buf, z_size_t len) {
     unsigned long sum2;
     unsigned n;
@@ -68,6 +230,11 @@ uLong ZEXPORT adler32_z(adler, buf, len)
     unsigned long sum2;
     unsigned n;
 
+#if defined(ADLER32_SIMD_NEON)
+    if (buf && len >= 64)
+        return adler32_simd_(adler, buf, len);
+#endif
+
     /* split Adler-32 into component sums */
     sum2 = (adler >> 16) & 0xffff;
     adler &= 0xffff;
diff --git a/deflate.c b/deflate.c
index f290783..31d1cfe 100644
--- a/deflate.c
+++ b/deflate.c
@@ -154,7 +154,16 @@ local const config configuration_table[10] = {
  *    characters, so that a running hash key can be computed from the previous
  *    key instead of complete recalculation each time.
  */
-#define UPDATE_HASH(s,h,c) (h = (((h) << s->hash_shift) ^ (c)) & s->hash_mask)
+#if defined(HASH_ARMV8_CRC32)
+#include <arm_acle.h>
+#define UPDATE_HASH_CRC_INTERNAL(s, h, c) \
+       (h = __crc32w(0, (c) & 0xFFFFFF) & ((deflate_state *)s)->hash_mask)
+
+#define UPDATE_HASH(s, h, c) \
+    UPDATE_HASH_CRC_INTERNAL(s, h, *(unsigned *)((uintptr_t)(&c) - (MIN_MATCH-1)))
+#else
+#define UPDATE_HASH(s,h,c) (h = (((h)<<s->hash_shift) ^ (c)) & s->hash_mask)
+#endif
 
 
 /* ===========================================================================
@@ -1226,14 +1235,15 @@ local unsigned read_buf(strm, buf, size)
     strm->avail_in  -= len;
 
     zmemcpy(buf, strm->next_in, len);
-    if (strm->state->wrap == 1) {
-        strm->adler = adler32(strm->adler, buf, len);
-    }
 #ifdef GZIP
-    else if (strm->state->wrap == 2) {
+    if (strm->state->wrap == 2) { /* use crc32 algo */
         strm->adler = crc32(strm->adler, buf, len);
-    }
+    } else 
 #endif
+    if (strm->state->wrap == 1) {
+        strm->adler = adler32(strm->adler, buf, len);
+    }
+
     strm->next_in  += len;
     strm->total_in += len;
 
diff --git a/inffast.c b/inffast.c
index 1fec7f3..84c5aba 100644
--- a/inffast.c
+++ b/inffast.c
@@ -57,6 +57,9 @@ unsigned start;         /* inflate()'s starting value for strm->avail_out */
     unsigned char FAR *out;     /* local strm->next_out */
     unsigned char FAR *beg;     /* inflate()'s initial strm->next_out */
     unsigned char FAR *end;     /* while out < end, enough space available */
+#if defined(INFLATE_CHUNK_SIMD_NEON)
+    unsigned char FAR *limit;   /* safety limit for chunky copies */
+#endif
 #ifdef INFLATE_STRICT
     unsigned dmax;              /* maximum distance from zlib header */
 #endif
@@ -89,7 +92,12 @@ unsigned start;         /* inflate()'s starting value for strm->avail_out */
 #endif
     wsize = state->wsize;
     whave = state->whave;
+#if defined(INFLATE_CHUNK_SIMD_NEON)    
+    limit = out + strm->avail_out;
+    wnext = (state->wnext == 0 && whave >= wsize) ? wsize : state->wnext;
+#else
     wnext = state->wnext;
+#endif
     window = state->window;
     hold = state->hold;
     bits = state->bits;
@@ -197,6 +205,45 @@ unsigned start;         /* inflate()'s starting value for strm->avail_out */
 #endif
                     }
                     from = window;
+#if defined(INFLATE_CHUNK_SIMD_NEON)
+                    if (wnext >= op) {          /* contiguous in window */
+                        from += wnext - op;
+                    }
+                    else {                      /* wrap around window */
+                        op -= wnext;
+                        from += wsize - op;
+                        if (op < len) {         /* some from end of window */
+                            len -= op;
+                            out = chunkcopy_safe(out, from, op, limit);
+                            from = window;      /* more from start of window */
+                            op = wnext;
+                            /* This (rare) case can create a situation where
+                               the first chunkcopy below must be checked.
+                             */
+                        }
+                    }
+                    if (op < len) {             /* still need some from output */
+                        out = chunkcopy_safe(out, from, op, limit);
+                        len -= op;
+                        /* When dist is small the amount of data that can be
+                           copied from the window is also small, and progress
+                           towards the dangerous end of the output buffer is
+                           also small.  This means that for trivial memsets and
+                           for chunkunroll_relaxed() a safety check is
+                           unnecessary.  However, these conditions may not be
+                           entered at all, and in that case it's possible that
+                           the main copy is near the end.
+                          */
+                        out = chunkunroll_relaxed(out, &dist, &len);
+                        out = chunkcopy_safe(out, out - dist, len, limit);
+                    }
+                    else {
+                        /* from points to window, so there is no risk of
+                           overlapping pointers requiring memset-like behaviour
+                         */
+                        out = chunkcopy_safe(out, from, len, limit);
+                    }
+#else
                     if (wnext == 0) {           /* very common case */
                         from += wsize - op;
                         if (op < len) {         /* some from window */
@@ -247,8 +294,18 @@ unsigned start;         /* inflate()'s starting value for strm->avail_out */
                         if (len > 1)
                             *out++ = *from++;
                     }
+#endif
                 }
-                else {
+                else { 
+#if defined(INFLATE_CHUNK_SIMD_NEON)
+                    /* Whole reference is in range of current output.  No
+                       range checks are necessary because we start with room
+                       for at least 258 bytes of output, so unroll and roundoff
+                       operations can write beyond `out+len` so long as they
+                       stay within 258 bytes of `out`.
+                     */
+                    out = chunkcopy_lapped_relaxed(out, dist, len);
+#else
                     from = out - dist;          /* copy direct from output */
                     do {                        /* minimum length is three */
                         *out++ = *from++;
@@ -260,7 +317,8 @@ unsigned start;         /* inflate()'s starting value for strm->avail_out */
                         *out++ = *from++;
                         if (len > 1)
                             *out++ = *from++;
-                    }
+                    }                   
+#endif
                 }
             }
             else if ((op & 64) == 0) {          /* 2nd level distance code */
diff --git a/inffast.h b/inffast.h
index e5c1aa4..259882c 100644
--- a/inffast.h
+++ b/inffast.h
@@ -8,4 +8,374 @@
    subject to change. Applications should only use zlib.h.
  */
 
+/*
+ * The chunk-copy code below deals with writing the decoded DEFLATE data to
+ * the output with SIMD methods to increase decode speed. Reading the input
+ * to the DEFLATE decoder with a wide, SIMD method can also increase decode
+ * speed. This option is supported on little endian machines, and reads the
+ * input data in 64-bit (8 byte) chunks.
+ */
+
 void ZLIB_INTERNAL inflate_fast(z_streamp strm, unsigned start);
+
+#if defined(INFLATE_CHUNK_SIMD_NEON)
+
+#include <stdint.h>
+#include "zutil.h"
+#include <arm_neon.h>
+
+typedef uint8x16_t z_vec128i_t;
+
+#define Z_STATIC_ASSERT(name, assert) typedef char name[(assert) ? 1 : -1]
+
+#if __STDC_VERSION__ >= 199901L
+#define Z_RESTRICT restrict
+#else
+#define Z_RESTRICT
+#endif
+
+#if defined(__clang__) || defined(__GNUC__) || defined(__llvm__)
+#define Z_BUILTIN_MEMCPY __builtin_memcpy
+#else
+#define Z_BUILTIN_MEMCPY zmemcpy
+#endif
+
+/*
+ * chunk copy type: the z_vec128i_t type size should be exactly 128-bits
+ * and equal to CHUNKCOPY_CHUNK_SIZE.
+ */
+#define CHUNKCOPY_CHUNK_SIZE sizeof(z_vec128i_t)
+
+Z_STATIC_ASSERT(vector_128_bits_wide,
+                CHUNKCOPY_CHUNK_SIZE == sizeof(int8_t) * 16);
+
+/*
+ * Ask the compiler to perform a wide, unaligned load with a machinevst1q_u8
+ * instruction appropriate for the z_vec128i_t type.
+ */
+static inline z_vec128i_t loadchunk(
+    const unsigned char FAR* s)
+{
+    z_vec128i_t v;
+    Z_BUILTIN_MEMCPY(&v, s, sizeof(v));
+    return v;
+}
+
+/*
+ * Ask the compiler to perform a wide, unaligned store with a machine
+ * instruction appropriate for the z_vec128i_t type.
+ */
+static inline void storechunk(
+    unsigned char FAR* d,
+    const z_vec128i_t v)
+{
+    Z_BUILTIN_MEMCPY(d, &v, sizeof(v));
+}
+
+/*
+ * Perform a memcpy-like operation, assuming that length is non-zero and that
+ * it's OK to overwrite at least CHUNKCOPY_CHUNK_SIZE bytes of output even if
+ * the length is shorter than this.
+ *
+ * It also guarantees that it will properly unroll the data if the distance
+ * between `out` and `from` is at least CHUNKCOPY_CHUNK_SIZE, which we rely on
+ * in chunkcopy_relaxed().
+ *
+ * Aside from better memory bus utilisation, this means that short copies
+ * (CHUNKCOPY_CHUNK_SIZE bytes or fewer) will fall straight through the loop
+ * without iteration, which will hopefully make the branch prediction more
+ * reliable.
+ */
+static inline unsigned char FAR* chunkcopy_core(
+    unsigned char FAR* out,
+    const unsigned char FAR* from,
+    unsigned len)
+{
+    const int bump = (--len % CHUNKCOPY_CHUNK_SIZE) + 1;
+    storechunk(out, loadchunk(from));
+    out += bump;
+    from += bump;
+    len /= CHUNKCOPY_CHUNK_SIZE;
+    while (len-- > 0) {
+        storechunk(out, loadchunk(from));
+        out += CHUNKCOPY_CHUNK_SIZE;
+        from += CHUNKCOPY_CHUNK_SIZE;
+    }
+    return out;
+}
+
+/*
+ * Like chunkcopy_core(), but avoid writing beyond of legal output.
+ *
+ * Accepts an additional pointer to the end of safe output.  A generic safe
+ * copy would use (out + len), but it's normally the case that the end of the
+ * output buffer is beyond the end of the current copy, and this can still be
+ * exploited.
+ */
+static inline unsigned char FAR* chunkcopy_core_safe(
+    unsigned char FAR* out,
+    const unsigned char FAR* from,
+    unsigned len,
+    unsigned char FAR* limit)
+{
+    Assert(out + len <= limit, "chunk copy exceeds safety limit");
+    if ((limit - out) < (ptrdiff_t) CHUNKCOPY_CHUNK_SIZE) {
+        const unsigned char FAR* Z_RESTRICT rfrom = from;
+        if (len & 8) {
+            Z_BUILTIN_MEMCPY(out, rfrom, 8);
+            out += 8;
+            rfrom += 8;
+        }
+        if (len & 4) {
+            Z_BUILTIN_MEMCPY(out, rfrom, 4);
+            out += 4;
+            rfrom += 4;
+        }
+        if (len & 2) {
+            Z_BUILTIN_MEMCPY(out, rfrom, 2);
+            out += 2;
+            rfrom += 2;
+        }
+        if (len & 1) {
+            *out++ = *rfrom++;
+        }
+        return out;
+    }
+    return chunkcopy_core(out, from, len);
+}
+
+/*
+ * Perform short copies until distance can be rewritten as being at least
+ * CHUNKCOPY_CHUNK_SIZE.
+ *
+ * Assumes it's OK to overwrite at least the first 2*CHUNKCOPY_CHUNK_SIZE
+ * bytes of output even if the copy is shorter than this.  This assumption
+ * holds within zlib inflate_fast(), which starts every iteration with at
+ * least 258 bytes of output space available (258 being the maximum length
+ * output from a single token; see inffast.c).
+ */
+static inline unsigned char FAR* chunkunroll_relaxed(
+    unsigned char FAR* out,
+    unsigned FAR* dist,
+    unsigned FAR* len)
+{
+    const unsigned char FAR* from = out - *dist;
+    while (*dist < *len && *dist < CHUNKCOPY_CHUNK_SIZE) {
+        storechunk(out, loadchunk(from));
+        out += *dist;
+        *len -= *dist;
+        *dist += *dist;
+    }
+    return out;
+}
+
+/*
+ * v_load64_dup(): load *src as an unaligned 64-bit int and duplicate it in
+ * every 64-bit component of the 128-bit result (64-bit int splat).
+ */
+static inline z_vec128i_t v_load64_dup(const void* src)
+{
+    return vcombine_u8(vld1_u8(src), vld1_u8(src));
+}
+
+/*
+ * v_load32_dup(): load *src as an unaligned 32-bit int and duplicate it in
+ * every 32-bit component of the 128-bit result (32-bit int splat).
+ */
+static inline z_vec128i_t v_load32_dup(const void* src)
+{
+    int32_t i32;
+    Z_BUILTIN_MEMCPY(&i32, src, sizeof(i32));
+    return vreinterpretq_u8_s32(vdupq_n_s32(i32));
+}
+
+/*
+ * v_load16_dup(): load *src as an unaligned 16-bit int and duplicate it in
+ * every 16-bit component of the 128-bit result (16-bit int splat).
+ */
+static inline z_vec128i_t v_load16_dup(const void* src)
+{
+    int16_t i16;
+    Z_BUILTIN_MEMCPY(&i16, src, sizeof(i16));
+    return vreinterpretq_u8_s16(vdupq_n_s16(i16));
+}
+
+/*
+ * v_load8_dup(): load the 8-bit int *src and duplicate it in every 8-bit
+ * component of the 128-bit result (8-bit int splat).
+ */
+static inline z_vec128i_t v_load8_dup(const void* src)
+{
+    return vld1q_dup_u8((const uint8_t*) src);
+}
+
+/*
+ * v_store_128(): store the 128-bit vec in a memory destination (that might
+ * not be 16-byte aligned) void* out.
+ */
+static inline void v_store_128(unsigned char* out, const z_vec128i_t vec)
+{
+    vst1q_u8(out, vec);
+}
+
+/*
+ * Perform an overlapping copy which behaves as a memset() operation, but
+ * supporting periods other than one, and assume that length is non-zero and
+ * that it's OK to overwrite at least CHUNKCOPY_CHUNK_SIZE*3 bytes of output
+ * even if the length is shorter than this.
+ */
+static inline unsigned char FAR* chunkset_store_result(
+    unsigned len,
+    unsigned char FAR* out,
+    z_vec128i_t v)
+{
+    do {
+        v_store_128(out, v);
+        out += sizeof(v);
+        len -= sizeof(v);
+    } while (len > 0);
+    return out;
+}
+
+static inline unsigned char FAR* chunkset_core(unsigned char FAR* out, unsigned period, unsigned len)
+{
+    z_vec128i_t v;
+    const int bump = ((len - 1) % sizeof(v)) + 1;
+    switch (period) {
+        case 1:
+            v = v_load8_dup(out - 1);
+            v_store_128(out, v);
+            out += bump;
+            len -= bump;
+            while (len > 0) {
+                v_store_128(out, v);
+                out += sizeof(v);
+                len -= sizeof(v);
+            }
+            return out;
+        case 2:
+            v = v_load16_dup(out - 2);
+            v_store_128(out, v);
+            out += bump;
+            len -= bump;
+            if (len > 0) {
+                v = v_load16_dup(out - 2);
+                out = chunkset_store_result(len, out, v);
+            }
+            return out;
+        case 4:
+            v = v_load32_dup(out - 4);
+            v_store_128(out, v);
+            out += bump;
+            len -= bump;
+            if (len > 0) {
+                v = v_load32_dup(out - 4);
+                out = chunkset_store_result(len, out, v);
+            }
+            return out;
+        case 8:
+            v = v_load64_dup(out - 8);
+            v_store_128(out, v);
+            out += bump;
+            len -= bump;
+            if (len > 0) {
+                v = v_load64_dup(out - 8);
+                out = chunkset_store_result(len, out, v);
+            }
+            return out;
+    }
+    out = chunkunroll_relaxed(out, &period, &len);
+    return chunkcopy_core(out, out - period, len);
+}
+
+/*
+ * Perform a memcpy-like operation, but assume that length is non-zero and that
+ * it's OK to overwrite at least CHUNKCOPY_CHUNK_SIZE bytes of output even if
+ * the length is shorter than this.
+ *
+ * Unlike chunkcopy_core() above, no guarantee is made regarding the behaviour
+ * of overlapping buffers, regardless of the distance between the pointers.
+ * This is reflected in the `restrict`-qualified pointers, allowing the
+ * compiler to re-order loads and stores.
+ */
+static inline unsigned char FAR* chunkcopy_relaxed(
+    unsigned char FAR* Z_RESTRICT out,
+    const unsigned char FAR* Z_RESTRICT from,
+    unsigned len)
+{
+    return chunkcopy_core(out, from, len);
+}
+
+/*
+ * Like chunkcopy_relaxed(), but avoid writing beyond of legal output.
+ *
+ * Unlike chunkcopy_core_safe() above, no guarantee is made regarding the
+ * behaviour of overlapping buffers, regardless of the distance between the
+ * pointers.  This is reflected in the `restrict`-qualified pointers, allowing
+ * the compiler to re-order loads and stores.
+ *
+ * Accepts an additional pointer to the end of safe output.  A generic safe
+ * copy would use (out + len), but it's normally the case that the end of the
+ * output buffer is beyond the end of the current copy, and this can still be
+ * exploited.
+ */
+static inline unsigned char FAR* chunkcopy_safe(
+    unsigned char FAR* out,
+    const unsigned char FAR* Z_RESTRICT from,
+    unsigned len,
+    unsigned char FAR* limit)
+{
+    Assert(out + len <= limit, "chunk copy exceeds safety limit");
+    return chunkcopy_core_safe(out, from, len, limit);
+}
+
+/*
+ * Perform chunky copy within the same buffer, where the source and destination
+ * may potentially overlap.
+ *
+ * Assumes that len > 0 on entry, and that it's safe to write at least
+ * CHUNKCOPY_CHUNK_SIZE*3 bytes to the output.
+ */
+static inline unsigned char FAR* chunkcopy_lapped_relaxed(
+    unsigned char FAR* out,
+    unsigned dist,
+    unsigned len)
+{
+    if (dist < len && dist < CHUNKCOPY_CHUNK_SIZE) {
+        return chunkset_core(out, dist, len);
+    }
+    return chunkcopy_core(out, out - dist, len);
+}
+
+/*
+ * Behave like chunkcopy_lapped_relaxed(), but avoid writing beyond of legal
+ * output.
+ *
+ * Accepts an additional pointer to the end of safe output.  A generic safe
+ * copy would use (out + len), but it's normally the case that the end of the
+ * output buffer is beyond the end of the current copy, and this can still be
+ * exploited.
+ */
+static inline unsigned char FAR* chunkcopy_lapped_safe(
+    unsigned char FAR* out,
+    unsigned dist,
+    unsigned len,
+    unsigned char FAR* limit)
+{
+    Assert(out + len <= limit, "chunk copy exceeds safety limit");
+    if ((limit - out) < (ptrdiff_t) (3 * CHUNKCOPY_CHUNK_SIZE)) {
+        while (len-- > 0) {
+            *out = *(out - dist);
+            out++;
+        }
+        return out;
+    }
+    return chunkcopy_lapped_relaxed(out, dist, len);
+}
+
+
+#undef Z_STATIC_ASSERT
+#undef Z_RESTRICT
+#undef Z_BUILTIN_MEMCPY
+
+#endif //defined(INFLATE_CHUNK_SIMD_NEON)
diff --git a/inflate.c b/inflate.c
index 8acbef4..4e695b1 100644
--- a/inflate.c
+++ b/inflate.c
@@ -408,9 +408,16 @@ unsigned copy;
 
     /* if it hasn't been done already, allocate space for the window */
     if (state->window == Z_NULL) {
+#if defined(INFLATE_CHUNK_SIMD_NEON)
+        unsigned wsize = 1U << state->wbits;
+        state->window = (unsigned char FAR *)
+                        ZALLOC(strm, CHUNKCOPY_CHUNK_SIZE + wsize,
+                               sizeof(unsigned char));
+#else
         state->window = (unsigned char FAR *)
                         ZALLOC(strm, 1U << state->wbits,
                                sizeof(unsigned char));
+#endif
         if (state->window == Z_NULL) return 1;
     }
 
-- 
2.33.0