Merge 10.5 into 10.6

5 files changed, 879 insertions, 867 deletions

diff --git a/mysys/CMakeLists.txt b/mysys/CMakeLists.txt
index d2d740aba17..5a4eeeba603 100644
--- a/mysys/CMakeLists.txt
+++ b/mysys/CMakeLists.txt
@@ -16,7 +16,7 @@
 
 INCLUDE_DIRECTORIES(${ZLIB_INCLUDE_DIR} ${CMAKE_SOURCE_DIR}/include ${CMAKE_SOURCE_DIR}/mysys)
 
-SET(MYSYS_SOURCES  array.c charset-def.c charset.c crc32ieee.cc my_default.c
+SET(MYSYS_SOURCES  array.c charset-def.c charset.c my_default.c
                 get_password.c
 				errors.c hash.c list.c
                                 mf_cache.c mf_dirname.c mf_fn_ext.c
@@ -60,19 +60,29 @@ ENDIF()
 
 IF(MSVC)
   SET(MYSYS_SOURCES ${MYSYS_SOURCES} crc32/crc32_x86.c)
+  IF(CMAKE_SIZEOF_VOID_P EQUAL 8)
+    SET (MYSYS_SOURCES ${MYSYS_SOURCES} crc32/crc32c_amd64.cc)
+  ENDIF()
   ADD_DEFINITIONS(-DHAVE_SSE42 -DHAVE_PCLMUL)
   IF(CLANG_CL)
-    SET_SOURCE_FILES_PROPERTIES(crc32/crc32_x86.cc crc32/crc32c.c PROPERTIES COMPILE_FLAGS "-msse4.2 -mpclmul")
+    SET_SOURCE_FILES_PROPERTIES(crc32/crc32_x86.c PROPERTIES COMPILE_FLAGS "-msse4.2 -mpclmul")
   ENDIF()
 ELSEIF(CMAKE_SYSTEM_PROCESSOR MATCHES "x86_64|amd64|i386|i686")
-  MY_CHECK_C_COMPILER_FLAG(-msse4.2)
-  MY_CHECK_C_COMPILER_FLAG(-mpclmul)
+  MY_CHECK_CXX_COMPILER_FLAG(-msse4.2)
+  MY_CHECK_CXX_COMPILER_FLAG(-mpclmul)
   CHECK_INCLUDE_FILE(cpuid.h HAVE_CPUID_H)
   CHECK_INCLUDE_FILE(x86intrin.h HAVE_X86INTRIN_H)
-  IF(have_C__msse4.2 AND have_C__mpclmul AND HAVE_CPUID_H AND HAVE_X86INTRIN_H)
-    SET(MYSYS_SOURCES ${MYSYS_SOURCES} crc32/crc32_x86.c)
-    SET_SOURCE_FILES_PROPERTIES(crc32/crc32_x86.c crc32/crc32c.cc PROPERTIES COMPILE_FLAGS "-msse4.2 -mpclmul")
-    ADD_DEFINITIONS(-DHAVE_SSE42 -DHAVE_PCLMUL)
+  IF(have_CXX__msse4.2 AND HAVE_CPUID_H)
+    ADD_DEFINITIONS(-DHAVE_SSE42)
+    IF (have_CXX__mpclmul AND HAVE_X86INTRIN_H)
+      ADD_DEFINITIONS(-DHAVE_PCLMUL)
+      SET(MYSYS_SOURCES ${MYSYS_SOURCES} crc32/crc32_x86.c)
+      SET_SOURCE_FILES_PROPERTIES(crc32/crc32_x86.c PROPERTIES COMPILE_FLAGS "-msse4.2 -mpclmul")
+      IF(CMAKE_SIZEOF_VOID_P EQUAL 8)
+	SET(MYSYS_SOURCES ${MYSYS_SOURCES} crc32/crc32c_amd64.cc)
+	SET_SOURCE_FILES_PROPERTIES(crc32/crc32c_amd64.cc PROPERTIES COMPILE_FLAGS "-msse4.2 -mpclmul")
+      ENDIF()
+    ENDIF()
   ENDIF()
 ELSEIF(CMAKE_SYSTEM_PROCESSOR MATCHES "aarch64|AARCH64")
   IF(CMAKE_COMPILER_IS_GNUCC)
@@ -129,11 +139,15 @@ ELSEIF(CMAKE_SYSTEM_PROCESSOR MATCHES "aarch64|AARCH64")
         COMPILE_FLAGS "-march=armv8-a+crc+crypto")
     ENDIF()
   ENDIF()
-ELSEIF(CMAKE_SYSTEM_PROCESSOR MATCHES "ppc64|powerpc64" OR CMAKE_SYSTEM_NAME MATCHES AIX)
+ENDIF()
+
+IF(CMAKE_SYSTEM_PROCESSOR MATCHES "ppc64|powerpc64" OR CMAKE_SYSTEM_NAME MATCHES AIX)
   SET(MYSYS_SOURCES ${MYSYS_SOURCES} crc32/crc32_ppc64.c crc32/crc32c_ppc.c)
   SET_SOURCE_FILES_PROPERTIES(crc32/crc32_ppc64.c crc32/crc32c_ppc.c PROPERTIES
         COMPILE_FLAGS "${COMPILE_FLAGS} -maltivec -mvsx -mpower8-vector -mcrypto -mpower8-vector")
   ADD_DEFINITIONS(-DHAVE_POWER8 -DHAS_ALTIVEC)
+ELSE()
+  SET (MYSYS_SOURCES ${MYSYS_SOURCES} crc32ieee.cc)
 ENDIF()
 
 IF(UNIX)
diff --git a/mysys/crc32/crc32_x86.c b/mysys/crc32/crc32_x86.c
index 1e5d2a0a089..f077399caca 100644
--- a/mysys/crc32/crc32_x86.c
+++ b/mysys/crc32/crc32_x86.c
@@ -1,4 +1,4 @@
-/* Copyright (c) 2020 MariaDB
+/* Copyright (c) 2020, 2021, MariaDB
 
    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
@@ -55,38 +55,14 @@
 #include <stdint.h>
 #include <stddef.h>
 
-#if defined(__GNUC__)
+#ifdef __GNUC__
 #include <x86intrin.h>
-#include <cpuid.h>
 #elif defined(_MSC_VER)
 #include <intrin.h>
 #else
 #error "unknown compiler"
 #endif
 
-static int has_sse42_and_pclmul(uint32_t recx)
-{
-  /* 1 << 20 is SSE42, 1 << 1 is PCLMULQDQ */
-#define bits_SSE42_AND_PCLMUL (1 << 20 | 1 << 1)
-  return (recx & bits_SSE42_AND_PCLMUL) == bits_SSE42_AND_PCLMUL;
-}
-
-#ifdef __GNUC__
-int crc32_pclmul_enabled(void)
-{
-  uint32_t reax= 0, rebx= 0, recx= 0, redx= 0;
-  __cpuid(1, reax, rebx, recx, redx);
-  return has_sse42_and_pclmul(recx);
-}
-#elif defined(_MSC_VER)
-int crc32_pclmul_enabled(void)
-{
-  int regs[4];
-  __cpuid(regs, 1);
-  return has_sse42_and_pclmul(regs[2]);
-}
-#endif
-
 /**
  * @brief Shifts left 128 bit register by specified number of bytes
  *
diff --git a/mysys/crc32/crc32c.cc b/mysys/crc32/crc32c.cc
index b6c80886ec1..082d467e7da 100644
--- a/mysys/crc32/crc32c.cc
+++ b/mysys/crc32/crc32c.cc
@@ -32,11 +32,20 @@ static inline uint32_t DecodeFixed32(const char *ptr)
 #endif
 
 #ifdef HAVE_SSE42
-#include <nmmintrin.h>
-#include <wmmintrin.h>
-#ifdef __GNUC__
-#include <cpuid.h>
-#endif
+# ifdef __GNUC__
+#  include <cpuid.h>
+#  if __GNUC__ < 5 && !defined __clang__
+/* the headers do not really work in GCC before version 5 */
+#   define _mm_crc32_u8(crc,data) __builtin_ia32_crc32qi(crc,data)
+#   define _mm_crc32_u32(crc,data) __builtin_ia32_crc32si(crc,data)
+#   define _mm_crc32_u64(crc,data) __builtin_ia32_crc32di(crc,data)
+#  else
+#   include <nmmintrin.h>
+#  endif
+#  define USE_SSE42 __attribute__((target("sse4.2")))
+# else
+#  define USE_SSE42 /* nothing */
+# endif
 #endif
 
 
@@ -337,19 +346,8 @@ static inline uint32_t LE_LOAD32(const uint8_t *p) {
   return DecodeFixed32(reinterpret_cast<const char*>(p));
 }
 
-#if defined(HAVE_SSE42) && (SIZEOF_SIZE_T == 8)
-
-static inline uint64_t DecodeFixed64(const char *ptr)
+static inline void Slow_CRC32(uint64_t* l, uint8_t const **p)
 {
-  return uint8korr(ptr);
-}
-
-static inline uint64_t LE_LOAD64(const uint8_t *p) {
-  return DecodeFixed64(reinterpret_cast<const char*>(p));
-}
-#endif
-
-static inline void Slow_CRC32(uint64_t* l, uint8_t const **p) {
   uint32_t c = static_cast<uint32_t>(*l ^ LE_LOAD32(*p));
   *p += 4;
   *l = table3_[c & 0xff] ^
@@ -365,27 +363,6 @@ static inline void Slow_CRC32(uint64_t* l, uint8_t const **p) {
   table0_[c >> 24];
 }
 
-__attribute__((unused)) static inline void Fast_CRC32(uint64_t* l, uint8_t const **p) {
-#ifndef HAVE_SSE42
-  Slow_CRC32(l, p);
-#elif (SIZEOF_SIZE_T == 8)
-  *l = _mm_crc32_u64(*l, LE_LOAD64(*p));
-  *p += 8;
-#else
-  *l = _mm_crc32_u32(static_cast<unsigned int>(*l), LE_LOAD32(*p));
-  *p += 4;
-  *l = _mm_crc32_u32(static_cast<unsigned int>(*l), LE_LOAD32(*p));
-  *p += 4;
-#endif
-}
-
-template<void (*CRC32)(uint64_t*, uint8_t const**)>
-uint32_t ExtendImpl(uint32_t crc, const char* buf, size_t size) {
-
-  const uint8_t *p = reinterpret_cast<const uint8_t *>(buf);
-  const uint8_t *e = p + size;
-  uint64_t l = crc ^ 0xffffffffu;
-
 #ifdef ALIGN
 #undef ALIGN
 #endif
@@ -398,70 +375,115 @@ uint32_t ExtendImpl(uint32_t crc, const char* buf, size_t size) {
     l = table0_[c] ^ (l >> 8);                  \
 } while (0)
 
+static uint32_t crc32c_slow(uint32_t crc, const char* buf, size_t size)
+{
+  const uint8_t *p = reinterpret_cast<const uint8_t *>(buf);
+  const uint8_t *e = p + size;
+  uint64_t l = crc ^ 0xffffffffu;
 
   // Point x at first 16-byte aligned byte in string.  This might be
   // just past the end of the string.
   const uintptr_t pval = reinterpret_cast<uintptr_t>(p);
   const uint8_t* x = reinterpret_cast<const uint8_t*>(ALIGN(pval, 4));
-  if (x <= e) {
+  if (x <= e)
     // Process bytes until finished or p is 16-byte aligned
-    while (p != x) {
+    while (p != x)
       STEP1;
-    }
-  }
   // Process bytes 16 at a time
-  while ((e-p) >= 16) {
-    CRC32(&l, &p);
-    CRC32(&l, &p);
+  while ((e-p) >= 16)
+  {
+    Slow_CRC32(&l, &p);
+    Slow_CRC32(&l, &p);
   }
   // Process bytes 8 at a time
-  while ((e-p) >= 8) {
-    CRC32(&l, &p);
-  }
+  while ((e-p) >= 8)
+    Slow_CRC32(&l, &p);
   // Process the last few bytes
-  while (p != e) {
+  while (p != e)
     STEP1;
-  }
-#undef STEP1
-#undef ALIGN
   return static_cast<uint32_t>(l ^ 0xffffffffu);
 }
 
-// Detect if ARM64 CRC or not.
-#ifndef HAVE_ARMV8_CRC
-// Detect if SS42 or not.
-#ifndef HAVE_POWER8
+#if defined HAVE_POWER8
+#elif defined HAVE_ARMV8_CRC
+#elif defined HAVE_SSE42
+constexpr uint32_t cpuid_ecx_SSE42= 1U << 20;
+constexpr uint32_t cpuid_ecx_SSE42_AND_PCLMUL= cpuid_ecx_SSE42 | 1U<<1;
 
-static bool isSSE42() {
-#ifndef HAVE_SSE42
-  return false;
-#elif defined(__GNUC__)
+static uint32_t cpuid_ecx()
+{
+#ifdef __GNUC__
   uint32_t reax= 0, rebx= 0, recx= 0, redx= 0;
   __cpuid(1, reax, rebx, recx, redx);
-  return (recx & ((int)1 << 20)) != 0;
-#elif defined(_MSC_VER)
-  int info[4];
-  __cpuid(info, 0x00000001);
-  return (info[2] & ((int)1 << 20)) != 0;
+  return recx;
+#elif defined _MSC_VER
+  int regs[4];
+  __cpuid(regs, 1);
+  return regs[2];
 #else
-  return false;
+# error "unknown compiler"
 #endif
 }
 
-#ifdef HAVE_SSE42
-extern "C" int crc32_pclmul_enabled();
-#endif
+extern "C" int crc32_pclmul_enabled(void)
+{
+  return !(~cpuid_ecx() & cpuid_ecx_SSE42_AND_PCLMUL);
+}
 
-static bool isPCLMULQDQ() {
-#ifdef HAVE_SSE42
-  return crc32_pclmul_enabled();
-#else
-  return false;
+#if SIZEOF_SIZE_T == 8
+extern "C" uint32_t crc32c_3way(uint32_t crc, const char *buf, size_t len);
+
+USE_SSE42
+static inline uint64_t LE_LOAD64(const uint8_t *ptr)
+{
+  return uint8korr(reinterpret_cast<const char*>(ptr));
+}
 #endif
+
+USE_SSE42
+static inline void Fast_CRC32(uint64_t* l, uint8_t const **p)
+{
+# if (SIZEOF_SIZE_T == 8)
+  *l = _mm_crc32_u64(*l, LE_LOAD64(*p));
+  *p += 8;
+# else
+  *l = _mm_crc32_u32(static_cast<unsigned int>(*l), LE_LOAD32(*p));
+  *p += 4;
+  *l = _mm_crc32_u32(static_cast<unsigned int>(*l), LE_LOAD32(*p));
+  *p += 4;
+# endif
 }
 
-#endif  // HAVE_POWER8
-#endif  // HAVE_ARMV8_CRC
+USE_SSE42
+static uint32_t crc32c_sse42(uint32_t crc, const char* buf, size_t size)
+{
+  const uint8_t *p = reinterpret_cast<const uint8_t *>(buf);
+  const uint8_t *e = p + size;
+  uint64_t l = crc ^ 0xffffffffu;
+
+  // Point x at first 16-byte aligned byte in string.  This might be
+  // just past the end of the string.
+  const uintptr_t pval = reinterpret_cast<uintptr_t>(p);
+  const uint8_t* x = reinterpret_cast<const uint8_t*>(ALIGN(pval, 4));
+  if (x <= e)
+    // Process bytes until finished or p is 16-byte aligned
+    while (p != x)
+      STEP1;
+  // Process bytes 16 at a time
+  while ((e-p) >= 16)
+  {
+    Fast_CRC32(&l, &p);
+    Fast_CRC32(&l, &p);
+  }
+  // Process bytes 8 at a time
+  while ((e-p) >= 8)
+    Fast_CRC32(&l, &p);
+  // Process the last few bytes
+  while (p != e)
+    STEP1;
+  return static_cast<uint32_t>(l ^ 0xffffffffu);
+}
+#endif
 
 typedef uint32_t (*Function)(uint32_t, const char*, size_t);
 
@@ -507,14 +529,6 @@ static int arch_ppc_probe(void) {
   return arch_ppc_crc32;
 }
 #endif  // __linux__
-
-static bool isAltiVec() {
-  if (arch_ppc_probe()) {
-    return true;
-  } else {
-    return false;
-  }
-}
 #endif
 
 #if defined(HAVE_ARMV8_CRC)
@@ -526,760 +540,59 @@ static uint32_t ExtendARMImpl(uint32_t crc, const char *buf, size_t size) {
 }
 #endif
 
-extern "C" const char * my_crc32c_implementation()
+static inline Function Choose_Extend()
 {
-#if defined(HAVE_POWER8) && defined(HAS_ALTIVEC)
+#if defined HAVE_POWER8 && defined HAS_ALTIVEC
   if (arch_ppc_probe())
-    return "Using POWER8 crc32 instructions";
+    return ExtendPPCImpl;
 #elif defined(HAVE_ARMV8_CRC)
-  const char *ret = crc32c_aarch64_available();
-  if (ret)
-    return ret ;
+  if (crc32c_aarch64_available())
+    return ExtendARMImpl;
 #elif HAVE_SSE42
-  if (isSSE42())
-  {
-    if (SIZEOF_SIZE_T == 8 && isPCLMULQDQ())
-      return "Using crc32 + pclmulqdq instructions";
-    return "Using SSE4.2 crc32 instructions";
+# if defined HAVE_PCLMUL && SIZEOF_SIZE_T == 8
+  switch (cpuid_ecx() & cpuid_ecx_SSE42_AND_PCLMUL) {
+  case cpuid_ecx_SSE42_AND_PCLMUL:
+    return crc32c_3way;
+  case cpuid_ecx_SSE42:
+    return crc32c_sse42;
   }
+# else
+  if (cpuid_ecx() & cpuid_ecx_SSE42)
+    return crc32c_sse42;
+# endif
 #endif
-  return "Using generic crc32 instructions";
-}
-
-
-/*
- * Copyright 2016 Ferry Toth, Exalon Delft BV, The Netherlands
- *  This software is provided 'as-is', without any express or implied
- * warranty.  In no event will the author be held liable for any damages
- * arising from the use of this software.
- *  Permission is granted to anyone to use this software for any purpose,
- * including commercial applications, and to alter it and redistribute it
- * freely, subject to the following restrictions:
- *  1. The origin of this software must not be misrepresented; you must not
- *   claim that you wrote the original software. If you use this software
- *   in a product, an acknowledgment in the product documentation would be
- *   appreciated but is not required.
- * 2. Altered source versions must be plainly marked as such, and must not be
- *   misrepresented as being the original software.
- * 3. This notice may not be removed or altered from any source distribution.
- *  Ferry Toth
- * ftoth@exalondelft.nl
- *
- * https://github.com/htot/crc32c
- *
- * Modified by Facebook
- *
- * Original intel whitepaper:
- * "Fast CRC Computation for iSCSI Polynomial Using CRC32 Instruction"
- * https://www.intel.com/content/dam/www/public/us/en/documents/white-papers/crc-iscsi-polynomial-crc32-instruction-paper.pdf
- *
- * This version is from the folly library, created by Dave Watson <davejwatson@fb.com>
- *
-*/
-#if defined HAVE_SSE42 && defined HAVE_PCLMUL && SIZEOF_SIZE_T == 8
-
-
-#define CRCtriplet(crc, buf, offset)                  \
-  crc##0 = _mm_crc32_u64(crc##0, *(buf##0 + offset)); \
-  crc##1 = _mm_crc32_u64(crc##1, *(buf##1 + offset)); \
-  crc##2 = _mm_crc32_u64(crc##2, *(buf##2 + offset));
-
-#define CRCduplet(crc, buf, offset)                   \
-  crc##0 = _mm_crc32_u64(crc##0, *(buf##0 + offset)); \
-  crc##1 = _mm_crc32_u64(crc##1, *(buf##1 + offset));
-
-#define CRCsinglet(crc, buf, offset)                    \
-  crc = _mm_crc32_u64(crc, *(uint64_t*)(buf + offset));
-
-
-// Numbers taken directly from intel whitepaper.
-// clang-format off
-static const uint64_t clmul_constants[] = {
-    0x14cd00bd6, 0x105ec76f0, 0x0ba4fc28e, 0x14cd00bd6,
-    0x1d82c63da, 0x0f20c0dfe, 0x09e4addf8, 0x0ba4fc28e,
-    0x039d3b296, 0x1384aa63a, 0x102f9b8a2, 0x1d82c63da,
-    0x14237f5e6, 0x01c291d04, 0x00d3b6092, 0x09e4addf8,
-    0x0c96cfdc0, 0x0740eef02, 0x18266e456, 0x039d3b296,
-    0x0daece73e, 0x0083a6eec, 0x0ab7aff2a, 0x102f9b8a2,
-    0x1248ea574, 0x1c1733996, 0x083348832, 0x14237f5e6,
-    0x12c743124, 0x02ad91c30, 0x0b9e02b86, 0x00d3b6092,
-    0x018b33a4e, 0x06992cea2, 0x1b331e26a, 0x0c96cfdc0,
-    0x17d35ba46, 0x07e908048, 0x1bf2e8b8a, 0x18266e456,
-    0x1a3e0968a, 0x11ed1f9d8, 0x0ce7f39f4, 0x0daece73e,
-    0x061d82e56, 0x0f1d0f55e, 0x0d270f1a2, 0x0ab7aff2a,
-    0x1c3f5f66c, 0x0a87ab8a8, 0x12ed0daac, 0x1248ea574,
-    0x065863b64, 0x08462d800, 0x11eef4f8e, 0x083348832,
-    0x1ee54f54c, 0x071d111a8, 0x0b3e32c28, 0x12c743124,
-    0x0064f7f26, 0x0ffd852c6, 0x0dd7e3b0c, 0x0b9e02b86,
-    0x0f285651c, 0x0dcb17aa4, 0x010746f3c, 0x018b33a4e,
-    0x1c24afea4, 0x0f37c5aee, 0x0271d9844, 0x1b331e26a,
-    0x08e766a0c, 0x06051d5a2, 0x093a5f730, 0x17d35ba46,
-    0x06cb08e5c, 0x11d5ca20e, 0x06b749fb2, 0x1bf2e8b8a,
-    0x1167f94f2, 0x021f3d99c, 0x0cec3662e, 0x1a3e0968a,
-    0x19329634a, 0x08f158014, 0x0e6fc4e6a, 0x0ce7f39f4,
-    0x08227bb8a, 0x1a5e82106, 0x0b0cd4768, 0x061d82e56,
-    0x13c2b89c4, 0x188815ab2, 0x0d7a4825c, 0x0d270f1a2,
-    0x10f5ff2ba, 0x105405f3e, 0x00167d312, 0x1c3f5f66c,
-    0x0f6076544, 0x0e9adf796, 0x026f6a60a, 0x12ed0daac,
-    0x1a2adb74e, 0x096638b34, 0x19d34af3a, 0x065863b64,
-    0x049c3cc9c, 0x1e50585a0, 0x068bce87a, 0x11eef4f8e,
-    0x1524fa6c6, 0x19f1c69dc, 0x16cba8aca, 0x1ee54f54c,
-    0x042d98888, 0x12913343e, 0x1329d9f7e, 0x0b3e32c28,
-    0x1b1c69528, 0x088f25a3a, 0x02178513a, 0x0064f7f26,
-    0x0e0ac139e, 0x04e36f0b0, 0x0170076fa, 0x0dd7e3b0c,
-    0x141a1a2e2, 0x0bd6f81f8, 0x16ad828b4, 0x0f285651c,
-    0x041d17b64, 0x19425cbba, 0x1fae1cc66, 0x010746f3c,
-    0x1a75b4b00, 0x18db37e8a, 0x0f872e54c, 0x1c24afea4,
-    0x01e41e9fc, 0x04c144932, 0x086d8e4d2, 0x0271d9844,
-    0x160f7af7a, 0x052148f02, 0x05bb8f1bc, 0x08e766a0c,
-    0x0a90fd27a, 0x0a3c6f37a, 0x0b3af077a, 0x093a5f730,
-    0x04984d782, 0x1d22c238e, 0x0ca6ef3ac, 0x06cb08e5c,
-    0x0234e0b26, 0x063ded06a, 0x1d88abd4a, 0x06b749fb2,
-    0x04597456a, 0x04d56973c, 0x0e9e28eb4, 0x1167f94f2,
-    0x07b3ff57a, 0x19385bf2e, 0x0c9c8b782, 0x0cec3662e,
-    0x13a9cba9e, 0x0e417f38a, 0x093e106a4, 0x19329634a,
-    0x167001a9c, 0x14e727980, 0x1ddffc5d4, 0x0e6fc4e6a,
-    0x00df04680, 0x0d104b8fc, 0x02342001e, 0x08227bb8a,
-    0x00a2a8d7e, 0x05b397730, 0x168763fa6, 0x0b0cd4768,
-    0x1ed5a407a, 0x0e78eb416, 0x0d2c3ed1a, 0x13c2b89c4,
-    0x0995a5724, 0x1641378f0, 0x19b1afbc4, 0x0d7a4825c,
-    0x109ffedc0, 0x08d96551c, 0x0f2271e60, 0x10f5ff2ba,
-    0x00b0bf8ca, 0x00bf80dd2, 0x123888b7a, 0x00167d312,
-    0x1e888f7dc, 0x18dcddd1c, 0x002ee03b2, 0x0f6076544,
-    0x183e8d8fe, 0x06a45d2b2, 0x133d7a042, 0x026f6a60a,
-    0x116b0f50c, 0x1dd3e10e8, 0x05fabe670, 0x1a2adb74e,
-    0x130004488, 0x0de87806c, 0x000bcf5f6, 0x19d34af3a,
-    0x18f0c7078, 0x014338754, 0x017f27698, 0x049c3cc9c,
-    0x058ca5f00, 0x15e3e77ee, 0x1af900c24, 0x068bce87a,
-    0x0b5cfca28, 0x0dd07448e, 0x0ded288f8, 0x1524fa6c6,
-    0x059f229bc, 0x1d8048348, 0x06d390dec, 0x16cba8aca,
-    0x037170390, 0x0a3e3e02c, 0x06353c1cc, 0x042d98888,
-    0x0c4584f5c, 0x0d73c7bea, 0x1f16a3418, 0x1329d9f7e,
-    0x0531377e2, 0x185137662, 0x1d8d9ca7c, 0x1b1c69528,
-    0x0b25b29f2, 0x18a08b5bc, 0x19fb2a8b0, 0x02178513a,
-    0x1a08fe6ac, 0x1da758ae0, 0x045cddf4e, 0x0e0ac139e,
-    0x1a91647f2, 0x169cf9eb0, 0x1a0f717c4, 0x0170076fa,
-};
-
-// Compute the crc32c value for buffer smaller than 8
-static inline void align_to_8(
-    size_t len,
-    uint64_t& crc0, // crc so far, updated on return
-    const unsigned char*& next) { // next data pointer, updated on return
-  uint32_t crc32bit = static_cast<uint32_t>(crc0);
-  if (len & 0x04) {
-    crc32bit = _mm_crc32_u32(crc32bit, *(uint32_t*)next);
-    next += sizeof(uint32_t);
-  }
-  if (len & 0x02) {
-    crc32bit = _mm_crc32_u16(crc32bit, *(uint16_t*)next);
-    next += sizeof(uint16_t);
-  }
-  if (len & 0x01) {
-    crc32bit = _mm_crc32_u8(crc32bit, *(next));
-    next++;
-  }
-  crc0 = crc32bit;
-}
-
-//
-// CombineCRC performs pclmulqdq multiplication of 2 partial CRC's and a well
-// chosen constant and xor's these with the remaining CRC.
-//
-static inline uint64_t CombineCRC(
-    size_t block_size,
-    uint64_t crc0,
-    uint64_t crc1,
-    uint64_t crc2,
-    const uint64_t* next2) {
-  const auto multiplier =
-      *(reinterpret_cast<const __m128i*>(clmul_constants) + block_size - 1);
-  const auto crc0_xmm = _mm_set_epi64x(0, crc0);
-  const auto res0 = _mm_clmulepi64_si128(crc0_xmm, multiplier, 0x00);
-  const auto crc1_xmm = _mm_set_epi64x(0, crc1);
-  const auto res1 = _mm_clmulepi64_si128(crc1_xmm, multiplier, 0x10);
-  const auto res = _mm_xor_si128(res0, res1);
-  crc0 = _mm_cvtsi128_si64(res);
-  crc0 = crc0 ^ *((uint64_t*)next2 - 1);
-  crc2 = _mm_crc32_u64(crc2, crc0);
-  return crc2;
+  return crc32c_slow;
 }
 
-// Compute CRC-32C using the Intel hardware instruction.
-static inline uint32_t crc32c_3way(uint32_t crc, const char* buf, size_t len) {
-  const unsigned char* next = (const unsigned char*)buf;
-  uint64_t count;
-  uint64_t crc0, crc1, crc2;
-  crc0 = crc ^ 0xffffffffu;
-
-
-  if (len >= 8) {
-    // if len > 216 then align and use triplets
-    if (len > 216) {
-      {
-        // Work on the bytes (< 8) before the first 8-byte alignment addr starts
-        auto align_bytes = (8 - (uintptr_t)next) & 7;
-        len -= align_bytes;
-        align_to_8(align_bytes, crc0, next);
-      }
-
-      // Now work on the remaining blocks
-      count = len / 24; // number of triplets
-      len %= 24; // bytes remaining
-      uint64_t n = count >> 7; // #blocks = first block + full blocks
-      uint64_t block_size = count & 127;
-      if (block_size == 0) {
-        block_size = 128;
-      } else {
-        n++;
-      }
-      // points to the first byte of the next block
-      const uint64_t* next0 = (uint64_t*)next + block_size;
-      const uint64_t* next1 = next0 + block_size;
-      const uint64_t* next2 = next1 + block_size;
+static const Function ChosenExtend= Choose_Extend();
 
-      crc1 = crc2 = 0;
-      // Use Duff's device, a for() loop inside a switch()
-      // statement. This needs to execute at least once, round len
-      // down to nearest triplet multiple
-      switch (block_size) {
-        case 128:
-          do {
-            // jumps here for a full block of len 128
-            CRCtriplet(crc, next, -128);
-              /* fallthrough */
-            case 127:
-              // jumps here or below for the first block smaller
-              CRCtriplet(crc, next, -127);
-              /* fallthrough */
-            case 126:
-              CRCtriplet(crc, next, -126); // than 128
-              /* fallthrough */
-            case 125:
-              CRCtriplet(crc, next, -125);
-              /* fallthrough */
-            case 124:
-              CRCtriplet(crc, next, -124);
-              /* fallthrough */
-            case 123:
-              CRCtriplet(crc, next, -123);
-              /* fallthrough */
-            case 122:
-              CRCtriplet(crc, next, -122);
-              /* fallthrough */
-            case 121:
-              CRCtriplet(crc, next, -121);
-              /* fallthrough */
-            case 120:
-              CRCtriplet(crc, next, -120);
-              /* fallthrough */
-            case 119:
-              CRCtriplet(crc, next, -119);
-              /* fallthrough */
-            case 118:
-              CRCtriplet(crc, next, -118);
-              /* fallthrough */
-            case 117:
-              CRCtriplet(crc, next, -117);
-              /* fallthrough */
-            case 116:
-              CRCtriplet(crc, next, -116);
-              /* fallthrough */
-            case 115:
-              CRCtriplet(crc, next, -115);
-              /* fallthrough */
-            case 114:
-              CRCtriplet(crc, next, -114);
-              /* fallthrough */
-            case 113:
-              CRCtriplet(crc, next, -113);
-              /* fallthrough */
-            case 112:
-              CRCtriplet(crc, next, -112);
-              /* fallthrough */
-            case 111:
-              CRCtriplet(crc, next, -111);
-              /* fallthrough */
-            case 110:
-              CRCtriplet(crc, next, -110);
-              /* fallthrough */
-            case 109:
-              CRCtriplet(crc, next, -109);
-              /* fallthrough */
-            case 108:
-              CRCtriplet(crc, next, -108);
-              /* fallthrough */
-            case 107:
-              CRCtriplet(crc, next, -107);
-              /* fallthrough */
-            case 106:
-              CRCtriplet(crc, next, -106);
-              /* fallthrough */
-            case 105:
-              CRCtriplet(crc, next, -105);
-              /* fallthrough */
-            case 104:
-              CRCtriplet(crc, next, -104);
-              /* fallthrough */
-            case 103:
-              CRCtriplet(crc, next, -103);
-              /* fallthrough */
-            case 102:
-              CRCtriplet(crc, next, -102);
-              /* fallthrough */
-            case 101:
-              CRCtriplet(crc, next, -101);
-              /* fallthrough */
-            case 100:
-              CRCtriplet(crc, next, -100);
-              /* fallthrough */
-            case 99:
-              CRCtriplet(crc, next, -99);
-              /* fallthrough */
-            case 98:
-              CRCtriplet(crc, next, -98);
-              /* fallthrough */
-            case 97:
-              CRCtriplet(crc, next, -97);
-              /* fallthrough */
-            case 96:
-              CRCtriplet(crc, next, -96);
-              /* fallthrough */
-            case 95:
-              CRCtriplet(crc, next, -95);
-              /* fallthrough */
-            case 94:
-              CRCtriplet(crc, next, -94);
-              /* fallthrough */
-            case 93:
-              CRCtriplet(crc, next, -93);
-              /* fallthrough */
-            case 92:
-              CRCtriplet(crc, next, -92);
-              /* fallthrough */
-            case 91:
-              CRCtriplet(crc, next, -91);
-              /* fallthrough */
-            case 90:
-              CRCtriplet(crc, next, -90);
-              /* fallthrough */
-            case 89:
-              CRCtriplet(crc, next, -89);
-              /* fallthrough */
-            case 88:
-              CRCtriplet(crc, next, -88);
-              /* fallthrough */
-            case 87:
-              CRCtriplet(crc, next, -87);
-              /* fallthrough */
-            case 86:
-              CRCtriplet(crc, next, -86);
-              /* fallthrough */
-            case 85:
-              CRCtriplet(crc, next, -85);
-              /* fallthrough */
-            case 84:
-              CRCtriplet(crc, next, -84);
-              /* fallthrough */
-            case 83:
-              CRCtriplet(crc, next, -83);
-              /* fallthrough */
-            case 82:
-              CRCtriplet(crc, next, -82);
-              /* fallthrough */
-            case 81:
-              CRCtriplet(crc, next, -81);
-              /* fallthrough */
-            case 80:
-              CRCtriplet(crc, next, -80);
-              /* fallthrough */
-            case 79:
-              CRCtriplet(crc, next, -79);
-              /* fallthrough */
-            case 78:
-              CRCtriplet(crc, next, -78);
-              /* fallthrough */
-            case 77:
-              CRCtriplet(crc, next, -77);
-              /* fallthrough */
-            case 76:
-              CRCtriplet(crc, next, -76);
-              /* fallthrough */
-            case 75:
-              CRCtriplet(crc, next, -75);
-              /* fallthrough */
-            case 74:
-              CRCtriplet(crc, next, -74);
-              /* fallthrough */
-            case 73:
-              CRCtriplet(crc, next, -73);
-              /* fallthrough */
-            case 72:
-              CRCtriplet(crc, next, -72);
-              /* fallthrough */
-            case 71:
-              CRCtriplet(crc, next, -71);
-              /* fallthrough */
-            case 70:
-              CRCtriplet(crc, next, -70);
-              /* fallthrough */
-            case 69:
-              CRCtriplet(crc, next, -69);
-              /* fallthrough */
-            case 68:
-              CRCtriplet(crc, next, -68);
-              /* fallthrough */
-            case 67:
-              CRCtriplet(crc, next, -67);
-              /* fallthrough */
-            case 66:
-              CRCtriplet(crc, next, -66);
-              /* fallthrough */
-            case 65:
-              CRCtriplet(crc, next, -65);
-              /* fallthrough */
-            case 64:
-              CRCtriplet(crc, next, -64);
-              /* fallthrough */
-            case 63:
-              CRCtriplet(crc, next, -63);
-              /* fallthrough */
-            case 62:
-              CRCtriplet(crc, next, -62);
-              /* fallthrough */
-            case 61:
-              CRCtriplet(crc, next, -61);
-              /* fallthrough */
-            case 60:
-              CRCtriplet(crc, next, -60);
-              /* fallthrough */
-            case 59:
-              CRCtriplet(crc, next, -59);
-              /* fallthrough */
-            case 58:
-              CRCtriplet(crc, next, -58);
-              /* fallthrough */
-            case 57:
-              CRCtriplet(crc, next, -57);
-              /* fallthrough */
-            case 56:
-              CRCtriplet(crc, next, -56);
-              /* fallthrough */
-            case 55:
-              CRCtriplet(crc, next, -55);
-              /* fallthrough */
-            case 54:
-              CRCtriplet(crc, next, -54);
-              /* fallthrough */
-            case 53:
-              CRCtriplet(crc, next, -53);
-              /* fallthrough */
-            case 52:
-              CRCtriplet(crc, next, -52);
-              /* fallthrough */
-            case 51:
-              CRCtriplet(crc, next, -51);
-              /* fallthrough */
-            case 50:
-              CRCtriplet(crc, next, -50);
-              /* fallthrough */
-            case 49:
-              CRCtriplet(crc, next, -49);
-              /* fallthrough */
-            case 48:
-              CRCtriplet(crc, next, -48);
-              /* fallthrough */
-            case 47:
-              CRCtriplet(crc, next, -47);
-              /* fallthrough */
-            case 46:
-              CRCtriplet(crc, next, -46);
-              /* fallthrough */
-            case 45:
-              CRCtriplet(crc, next, -45);
-              /* fallthrough */
-            case 44:
-              CRCtriplet(crc, next, -44);
-              /* fallthrough */
-            case 43:
-              CRCtriplet(crc, next, -43);
-              /* fallthrough */
-            case 42:
-              CRCtriplet(crc, next, -42);
-              /* fallthrough */
-            case 41:
-              CRCtriplet(crc, next, -41);
-              /* fallthrough */
-            case 40:
-              CRCtriplet(crc, next, -40);
-              /* fallthrough */
-            case 39:
-              CRCtriplet(crc, next, -39);
-              /* fallthrough */
-            case 38:
-              CRCtriplet(crc, next, -38);
-              /* fallthrough */
-            case 37:
-              CRCtriplet(crc, next, -37);
-              /* fallthrough */
-            case 36:
-              CRCtriplet(crc, next, -36);
-              /* fallthrough */
-            case 35:
-              CRCtriplet(crc, next, -35);
-              /* fallthrough */
-            case 34:
-              CRCtriplet(crc, next, -34);
-              /* fallthrough */
-            case 33:
-              CRCtriplet(crc, next, -33);
-              /* fallthrough */
-            case 32:
-              CRCtriplet(crc, next, -32);
-              /* fallthrough */
-            case 31:
-              CRCtriplet(crc, next, -31);
-              /* fallthrough */
-            case 30:
-              CRCtriplet(crc, next, -30);
-              /* fallthrough */
-            case 29:
-              CRCtriplet(crc, next, -29);
-              /* fallthrough */
-            case 28:
-              CRCtriplet(crc, next, -28);
-              /* fallthrough */
-            case 27:
-              CRCtriplet(crc, next, -27);
-              /* fallthrough */
-            case 26:
-              CRCtriplet(crc, next, -26);
-              /* fallthrough */
-            case 25:
-              CRCtriplet(crc, next, -25);
-              /* fallthrough */
-            case 24:
-              CRCtriplet(crc, next, -24);
-              /* fallthrough */
-            case 23:
-              CRCtriplet(crc, next, -23);
-              /* fallthrough */
-            case 22:
-              CRCtriplet(crc, next, -22);
-              /* fallthrough */
-            case 21:
-              CRCtriplet(crc, next, -21);
-              /* fallthrough */
-            case 20:
-              CRCtriplet(crc, next, -20);
-              /* fallthrough */
-            case 19:
-              CRCtriplet(crc, next, -19);
-              /* fallthrough */
-            case 18:
-              CRCtriplet(crc, next, -18);
-              /* fallthrough */
-            case 17:
-              CRCtriplet(crc, next, -17);
-              /* fallthrough */
-            case 16:
-              CRCtriplet(crc, next, -16);
-              /* fallthrough */
-            case 15:
-              CRCtriplet(crc, next, -15);
-              /* fallthrough */
-            case 14:
-              CRCtriplet(crc, next, -14);
-              /* fallthrough */
-            case 13:
-              CRCtriplet(crc, next, -13);
-              /* fallthrough */
-            case 12:
-              CRCtriplet(crc, next, -12);
-              /* fallthrough */
-            case 11:
-              CRCtriplet(crc, next, -11);
-              /* fallthrough */
-            case 10:
-              CRCtriplet(crc, next, -10);
-              /* fallthrough */
-            case 9:
-              CRCtriplet(crc, next, -9);
-              /* fallthrough */
-            case 8:
-              CRCtriplet(crc, next, -8);
-              /* fallthrough */
-            case 7:
-              CRCtriplet(crc, next, -7);
-              /* fallthrough */
-            case 6:
-              CRCtriplet(crc, next, -6);
-              /* fallthrough */
-            case 5:
-              CRCtriplet(crc, next, -5);
-              /* fallthrough */
-            case 4:
-              CRCtriplet(crc, next, -4);
-              /* fallthrough */
-            case 3:
-              CRCtriplet(crc, next, -3);
-              /* fallthrough */
-            case 2:
-              CRCtriplet(crc, next, -2);
-              /* fallthrough */
-            case 1:
-              CRCduplet(crc, next, -1); // the final triplet is actually only 2
-              //{ CombineCRC(); }
-              crc0 = CombineCRC(block_size, crc0, crc1, crc2, next2);
-              if (--n > 0) {
-                crc1 = crc2 = 0;
-                block_size = 128;
-                // points to the first byte of the next block
-                next0 = next2 + 128;
-                next1 = next0 + 128; // from here on all blocks are 128 long
-                next2 = next1 + 128;
-              }
-              /* fallthrough */
-            case 0:;
-          } while (n > 0);
-      }
-      next = (const unsigned char*)next2;
-    }
-    uint64_t count2 = len >> 3; // 216 of less bytes is 27 or less singlets
-    len = len & 7;
-    next += (count2 * 8);
-    switch (count2) {
-      case 27:
-        CRCsinglet(crc0, next, -27 * 8);
-        /* fallthrough */
-      case 26:
-        CRCsinglet(crc0, next, -26 * 8);
-        /* fallthrough */
-      case 25:
-        CRCsinglet(crc0, next, -25 * 8);
-        /* fallthrough */
-      case 24:
-        CRCsinglet(crc0, next, -24 * 8);
-        /* fallthrough */
-      case 23:
-        CRCsinglet(crc0, next, -23 * 8);
-        /* fallthrough */
-      case 22:
-        CRCsinglet(crc0, next, -22 * 8);
-        /* fallthrough */
-      case 21:
-        CRCsinglet(crc0, next, -21 * 8);
-        /* fallthrough */
-      case 20:
-        CRCsinglet(crc0, next, -20 * 8);
-        /* fallthrough */
-      case 19:
-        CRCsinglet(crc0, next, -19 * 8);
-        /* fallthrough */
-      case 18:
-        CRCsinglet(crc0, next, -18 * 8);
-        /* fallthrough */
-      case 17:
-        CRCsinglet(crc0, next, -17 * 8);
-        /* fallthrough */
-      case 16:
-        CRCsinglet(crc0, next, -16 * 8);
-        /* fallthrough */
-      case 15:
-        CRCsinglet(crc0, next, -15 * 8);
-        /* fallthrough */
-      case 14:
-        CRCsinglet(crc0, next, -14 * 8);
-        /* fallthrough */
-      case 13:
-        CRCsinglet(crc0, next, -13 * 8);
-        /* fallthrough */
-      case 12:
-        CRCsinglet(crc0, next, -12 * 8);
-        /* fallthrough */
-      case 11:
-        CRCsinglet(crc0, next, -11 * 8);
-        /* fallthrough */
-      case 10:
-        CRCsinglet(crc0, next, -10 * 8);
-        /* fallthrough */
-      case 9:
-        CRCsinglet(crc0, next, -9 * 8);
-        /* fallthrough */
-      case 8:
-        CRCsinglet(crc0, next, -8 * 8);
-        /* fallthrough */
-      case 7:
-        CRCsinglet(crc0, next, -7 * 8);
-        /* fallthrough */
-      case 6:
-        CRCsinglet(crc0, next, -6 * 8);
-        /* fallthrough */
-      case 5:
-        CRCsinglet(crc0, next, -5 * 8);
-        /* fallthrough */
-      case 4:
-        CRCsinglet(crc0, next, -4 * 8);
-        /* fallthrough */
-      case 3:
-        CRCsinglet(crc0, next, -3 * 8);
-        /* fallthrough */
-      case 2:
-        CRCsinglet(crc0, next, -2 * 8);
-        /* fallthrough */
-      case 1:
-        CRCsinglet(crc0, next, -1 * 8);
-        /* fallthrough */
-      case 0:;
-    }
-  }
-  {
-    align_to_8(len, crc0, next);
-    return (uint32_t)crc0 ^ 0xffffffffu;
-  }
+static inline uint32_t Extend(uint32_t crc, const char* buf, size_t size)
+{
+  return ChosenExtend(crc, buf, size);
 }
 
-#else
-#define NO_THREEWAY_CRC32C
-#endif //HAVE_SSE42 && HAVE_PCLMUL
-
-static inline Function Choose_Extend() {
-#ifdef HAVE_POWER8
-  return isAltiVec() ? ExtendPPCImpl : ExtendImpl<Slow_CRC32>;
+extern "C" const char *my_crc32c_implementation()
+{
+#if defined(HAVE_POWER8) && defined(HAS_ALTIVEC)
+  if (ChosenExtend == ExtendPPCImpl)
+    return "Using POWER8 crc32 instructions";
 #elif defined(HAVE_ARMV8_CRC)
-  if(crc32c_aarch64_available()) {
-    return ExtendARMImpl;
-  } else {
-    return ExtendImpl<Slow_CRC32>;
-  }
-#else
-  if (isSSE42()) {
-    if (isPCLMULQDQ()) {
-#if defined HAVE_SSE42  && defined HAVE_PCLMUL && !defined NO_THREEWAY_CRC32C
-      return crc32c_3way;
-#else
-    return ExtendImpl<Fast_CRC32>; // Fast_CRC32 will check HAVE_SSE42 itself
-#endif
-    }
-    else {  // no runtime PCLMULQDQ support but has SSE42 support
-      return ExtendImpl<Fast_CRC32>;
-    }
-  } // end of isSSE42()
-  else {
-    return ExtendImpl<Slow_CRC32>;
-  }
+  if (const char *ret= crc32c_aarch64_available())
+    return ret;
+#elif HAVE_SSE42
+# if defined HAVE_PCLMUL && SIZEOF_SIZE_T == 8
+  if (ChosenExtend == crc32c_3way)
+    return "Using crc32 + pclmulqdq instructions";
+# endif
+  if (ChosenExtend == crc32c_sse42)
+    return "Using SSE4.2 crc32 instructions";
 #endif
-}
-
-static const Function ChosenExtend = Choose_Extend();
-
-static inline uint32_t Extend(uint32_t crc, const char* buf, size_t size) {
-  return ChosenExtend(crc, buf, size);
+  return "Using generic crc32 instructions";
 }
 }  // namespace crc32c
 }  // namespace mysys_namespace
 
-extern "C" unsigned int my_crc32c(unsigned int crc, const char *buf, size_t size)
+extern "C" unsigned my_crc32c(unsigned int crc, const char *buf, size_t size)
 {
   return mysys_namespace::crc32c::Extend(crc,buf, size);
 }
diff --git a/mysys/crc32/crc32c_amd64.cc b/mysys/crc32/crc32c_amd64.cc
new file mode 100644
index 00000000000..22c492b457f
--- /dev/null
+++ b/mysys/crc32/crc32c_amd64.cc
@@ -0,0 +1,711 @@
+/* Copyright (c) 2020, 2021, MariaDB
+
+   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; version 2 of the License.
+
+   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 St, Fifth Floor, Boston, MA 02110-1335  USA */
+
+/*
+ * Copyright 2016 Ferry Toth, Exalon Delft BV, The Netherlands
+ *  This software is provided 'as-is', without any express or implied
+ * warranty.  In no event will the author be held liable for any damages
+ * arising from the use of this software.
+ *  Permission is granted to anyone to use this software for any purpose,
+ * including commercial applications, and to alter it and redistribute it
+ * freely, subject to the following restrictions:
+ *  1. The origin of this software must not be misrepresented; you must not
+ *   claim that you wrote the original software. If you use this software
+ *   in a product, an acknowledgment in the product documentation would be
+ *   appreciated but is not required.
+ * 2. Altered source versions must be plainly marked as such, and must not be
+ *   misrepresented as being the original software.
+ * 3. This notice may not be removed or altered from any source distribution.
+ *  Ferry Toth
+ * ftoth@exalondelft.nl
+ *
+ * https://github.com/htot/crc32c
+ *
+ * Modified by Facebook
+ *
+ * Original intel whitepaper:
+ * "Fast CRC Computation for iSCSI Polynomial Using CRC32 Instruction"
+ * https://www.intel.com/content/dam/www/public/us/en/documents/white-papers/crc-iscsi-polynomial-crc32-instruction-paper.pdf
+ *
+ * This version is from the folly library, created by Dave Watson <davejwatson@fb.com>
+ *
+*/
+
+#include <stdint.h>
+#include <nmmintrin.h>
+#include <wmmintrin.h>
+
+
+#define CRCtriplet(crc, buf, offset)                  \
+  crc##0 = _mm_crc32_u64(crc##0, *(buf##0 + offset)); \
+  crc##1 = _mm_crc32_u64(crc##1, *(buf##1 + offset)); \
+  crc##2 = _mm_crc32_u64(crc##2, *(buf##2 + offset));
+
+#define CRCduplet(crc, buf, offset)                   \
+  crc##0 = _mm_crc32_u64(crc##0, *(buf##0 + offset)); \
+  crc##1 = _mm_crc32_u64(crc##1, *(buf##1 + offset));
+
+#define CRCsinglet(crc, buf, offset)                    \
+  crc = _mm_crc32_u64(crc, *(uint64_t*)(buf + offset));
+
+
+// Numbers taken directly from intel whitepaper.
+// clang-format off
+static const uint64_t clmul_constants alignas(16) [] = {
+    0x14cd00bd6, 0x105ec76f0, 0x0ba4fc28e, 0x14cd00bd6,
+    0x1d82c63da, 0x0f20c0dfe, 0x09e4addf8, 0x0ba4fc28e,
+    0x039d3b296, 0x1384aa63a, 0x102f9b8a2, 0x1d82c63da,
+    0x14237f5e6, 0x01c291d04, 0x00d3b6092, 0x09e4addf8,
+    0x0c96cfdc0, 0x0740eef02, 0x18266e456, 0x039d3b296,
+    0x0daece73e, 0x0083a6eec, 0x0ab7aff2a, 0x102f9b8a2,
+    0x1248ea574, 0x1c1733996, 0x083348832, 0x14237f5e6,
+    0x12c743124, 0x02ad91c30, 0x0b9e02b86, 0x00d3b6092,
+    0x018b33a4e, 0x06992cea2, 0x1b331e26a, 0x0c96cfdc0,
+    0x17d35ba46, 0x07e908048, 0x1bf2e8b8a, 0x18266e456,
+    0x1a3e0968a, 0x11ed1f9d8, 0x0ce7f39f4, 0x0daece73e,
+    0x061d82e56, 0x0f1d0f55e, 0x0d270f1a2, 0x0ab7aff2a,
+    0x1c3f5f66c, 0x0a87ab8a8, 0x12ed0daac, 0x1248ea574,
+    0x065863b64, 0x08462d800, 0x11eef4f8e, 0x083348832,
+    0x1ee54f54c, 0x071d111a8, 0x0b3e32c28, 0x12c743124,
+    0x0064f7f26, 0x0ffd852c6, 0x0dd7e3b0c, 0x0b9e02b86,
+    0x0f285651c, 0x0dcb17aa4, 0x010746f3c, 0x018b33a4e,
+    0x1c24afea4, 0x0f37c5aee, 0x0271d9844, 0x1b331e26a,
+    0x08e766a0c, 0x06051d5a2, 0x093a5f730, 0x17d35ba46,
+    0x06cb08e5c, 0x11d5ca20e, 0x06b749fb2, 0x1bf2e8b8a,
+    0x1167f94f2, 0x021f3d99c, 0x0cec3662e, 0x1a3e0968a,
+    0x19329634a, 0x08f158014, 0x0e6fc4e6a, 0x0ce7f39f4,
+    0x08227bb8a, 0x1a5e82106, 0x0b0cd4768, 0x061d82e56,
+    0x13c2b89c4, 0x188815ab2, 0x0d7a4825c, 0x0d270f1a2,
+    0x10f5ff2ba, 0x105405f3e, 0x00167d312, 0x1c3f5f66c,
+    0x0f6076544, 0x0e9adf796, 0x026f6a60a, 0x12ed0daac,
+    0x1a2adb74e, 0x096638b34, 0x19d34af3a, 0x065863b64,
+    0x049c3cc9c, 0x1e50585a0, 0x068bce87a, 0x11eef4f8e,
+    0x1524fa6c6, 0x19f1c69dc, 0x16cba8aca, 0x1ee54f54c,
+    0x042d98888, 0x12913343e, 0x1329d9f7e, 0x0b3e32c28,
+    0x1b1c69528, 0x088f25a3a, 0x02178513a, 0x0064f7f26,
+    0x0e0ac139e, 0x04e36f0b0, 0x0170076fa, 0x0dd7e3b0c,
+    0x141a1a2e2, 0x0bd6f81f8, 0x16ad828b4, 0x0f285651c,
+    0x041d17b64, 0x19425cbba, 0x1fae1cc66, 0x010746f3c,
+    0x1a75b4b00, 0x18db37e8a, 0x0f872e54c, 0x1c24afea4,
+    0x01e41e9fc, 0x04c144932, 0x086d8e4d2, 0x0271d9844,
+    0x160f7af7a, 0x052148f02, 0x05bb8f1bc, 0x08e766a0c,
+    0x0a90fd27a, 0x0a3c6f37a, 0x0b3af077a, 0x093a5f730,
+    0x04984d782, 0x1d22c238e, 0x0ca6ef3ac, 0x06cb08e5c,
+    0x0234e0b26, 0x063ded06a, 0x1d88abd4a, 0x06b749fb2,
+    0x04597456a, 0x04d56973c, 0x0e9e28eb4, 0x1167f94f2,
+    0x07b3ff57a, 0x19385bf2e, 0x0c9c8b782, 0x0cec3662e,
+    0x13a9cba9e, 0x0e417f38a, 0x093e106a4, 0x19329634a,
+    0x167001a9c, 0x14e727980, 0x1ddffc5d4, 0x0e6fc4e6a,
+    0x00df04680, 0x0d104b8fc, 0x02342001e, 0x08227bb8a,
+    0x00a2a8d7e, 0x05b397730, 0x168763fa6, 0x0b0cd4768,
+    0x1ed5a407a, 0x0e78eb416, 0x0d2c3ed1a, 0x13c2b89c4,
+    0x0995a5724, 0x1641378f0, 0x19b1afbc4, 0x0d7a4825c,
+    0x109ffedc0, 0x08d96551c, 0x0f2271e60, 0x10f5ff2ba,
+    0x00b0bf8ca, 0x00bf80dd2, 0x123888b7a, 0x00167d312,
+    0x1e888f7dc, 0x18dcddd1c, 0x002ee03b2, 0x0f6076544,
+    0x183e8d8fe, 0x06a45d2b2, 0x133d7a042, 0x026f6a60a,
+    0x116b0f50c, 0x1dd3e10e8, 0x05fabe670, 0x1a2adb74e,
+    0x130004488, 0x0de87806c, 0x000bcf5f6, 0x19d34af3a,
+    0x18f0c7078, 0x014338754, 0x017f27698, 0x049c3cc9c,
+    0x058ca5f00, 0x15e3e77ee, 0x1af900c24, 0x068bce87a,
+    0x0b5cfca28, 0x0dd07448e, 0x0ded288f8, 0x1524fa6c6,
+    0x059f229bc, 0x1d8048348, 0x06d390dec, 0x16cba8aca,
+    0x037170390, 0x0a3e3e02c, 0x06353c1cc, 0x042d98888,
+    0x0c4584f5c, 0x0d73c7bea, 0x1f16a3418, 0x1329d9f7e,
+    0x0531377e2, 0x185137662, 0x1d8d9ca7c, 0x1b1c69528,
+    0x0b25b29f2, 0x18a08b5bc, 0x19fb2a8b0, 0x02178513a,
+    0x1a08fe6ac, 0x1da758ae0, 0x045cddf4e, 0x0e0ac139e,
+    0x1a91647f2, 0x169cf9eb0, 0x1a0f717c4, 0x0170076fa,
+};
+
+// Compute the crc32c value for buffer smaller than 8
+static inline void align_to_8(
+    size_t len,
+    uint64_t& crc0, // crc so far, updated on return
+    const unsigned char*& next) { // next data pointer, updated on return
+  uint32_t crc32bit = static_cast<uint32_t>(crc0);
+  if (len & 0x04) {
+    crc32bit = _mm_crc32_u32(crc32bit, *(uint32_t*)next);
+    next += sizeof(uint32_t);
+  }
+  if (len & 0x02) {
+    crc32bit = _mm_crc32_u16(crc32bit, *(uint16_t*)next);
+    next += sizeof(uint16_t);
+  }
+  if (len & 0x01) {
+    crc32bit = _mm_crc32_u8(crc32bit, *(next));
+    next++;
+  }
+  crc0 = crc32bit;
+}
+
+//
+// CombineCRC performs pclmulqdq multiplication of 2 partial CRC's and a well
+// chosen constant and xor's these with the remaining CRC.
+//
+static inline uint64_t CombineCRC(
+    size_t block_size,
+    uint64_t crc0,
+    uint64_t crc1,
+    uint64_t crc2,
+    const uint64_t* next2) {
+  const auto multiplier =
+      *(reinterpret_cast<const __m128i*>(clmul_constants) + block_size - 1);
+  const auto crc0_xmm = _mm_set_epi64x(0, crc0);
+  const auto res0 = _mm_clmulepi64_si128(crc0_xmm, multiplier, 0x00);
+  const auto crc1_xmm = _mm_set_epi64x(0, crc1);
+  const auto res1 = _mm_clmulepi64_si128(crc1_xmm, multiplier, 0x10);
+  const auto res = _mm_xor_si128(res0, res1);
+  crc0 = _mm_cvtsi128_si64(res);
+  crc0 = crc0 ^ *((uint64_t*)next2 - 1);
+  crc2 = _mm_crc32_u64(crc2, crc0);
+  return crc2;
+}
+
+// Compute CRC-32C using the Intel hardware instruction.
+extern "C"
+uint32_t crc32c_3way(uint32_t crc, const char *buf, size_t len)
+{
+  const unsigned char* next = (const unsigned char*)buf;
+  uint64_t count;
+  uint64_t crc0, crc1, crc2;
+  crc0 = crc ^ 0xffffffffu;
+
+
+  if (len >= 8) {
+    // if len > 216 then align and use triplets
+    if (len > 216) {
+      {
+        // Work on the bytes (< 8) before the first 8-byte alignment addr starts
+        auto align_bytes = (8 - (uintptr_t)next) & 7;
+        len -= align_bytes;
+        align_to_8(align_bytes, crc0, next);
+      }
+
+      // Now work on the remaining blocks
+      count = len / 24; // number of triplets
+      len %= 24; // bytes remaining
+      uint64_t n = count >> 7; // #blocks = first block + full blocks
+      uint64_t block_size = count & 127;
+      if (block_size == 0) {
+        block_size = 128;
+      } else {
+        n++;
+      }
+      // points to the first byte of the next block
+      const uint64_t* next0 = (uint64_t*)next + block_size;
+      const uint64_t* next1 = next0 + block_size;
+      const uint64_t* next2 = next1 + block_size;
+
+      crc1 = crc2 = 0;
+      // Use Duff's device, a for() loop inside a switch()
+      // statement. This needs to execute at least once, round len
+      // down to nearest triplet multiple
+      switch (block_size) {
+        case 128:
+          do {
+            // jumps here for a full block of len 128
+            CRCtriplet(crc, next, -128);
+              /* fallthrough */
+            case 127:
+              // jumps here or below for the first block smaller
+              CRCtriplet(crc, next, -127);
+              /* fallthrough */
+            case 126:
+              CRCtriplet(crc, next, -126); // than 128
+              /* fallthrough */
+            case 125:
+              CRCtriplet(crc, next, -125);
+              /* fallthrough */
+            case 124:
+              CRCtriplet(crc, next, -124);
+              /* fallthrough */
+            case 123:
+              CRCtriplet(crc, next, -123);
+              /* fallthrough */
+            case 122:
+              CRCtriplet(crc, next, -122);
+              /* fallthrough */
+            case 121:
+              CRCtriplet(crc, next, -121);
+              /* fallthrough */
+            case 120:
+              CRCtriplet(crc, next, -120);
+              /* fallthrough */
+            case 119:
+              CRCtriplet(crc, next, -119);
+              /* fallthrough */
+            case 118:
+              CRCtriplet(crc, next, -118);
+              /* fallthrough */
+            case 117:
+              CRCtriplet(crc, next, -117);
+              /* fallthrough */
+            case 116:
+              CRCtriplet(crc, next, -116);
+              /* fallthrough */
+            case 115:
+              CRCtriplet(crc, next, -115);
+              /* fallthrough */
+            case 114:
+              CRCtriplet(crc, next, -114);
+              /* fallthrough */
+            case 113:
+              CRCtriplet(crc, next, -113);
+              /* fallthrough */
+            case 112:
+              CRCtriplet(crc, next, -112);
+              /* fallthrough */
+            case 111:
+              CRCtriplet(crc, next, -111);
+              /* fallthrough */
+            case 110:
+              CRCtriplet(crc, next, -110);
+              /* fallthrough */
+            case 109:
+              CRCtriplet(crc, next, -109);
+              /* fallthrough */
+            case 108:
+              CRCtriplet(crc, next, -108);
+              /* fallthrough */
+            case 107:
+              CRCtriplet(crc, next, -107);
+              /* fallthrough */
+            case 106:
+              CRCtriplet(crc, next, -106);
+              /* fallthrough */
+            case 105:
+              CRCtriplet(crc, next, -105);
+              /* fallthrough */
+            case 104:
+              CRCtriplet(crc, next, -104);
+              /* fallthrough */
+            case 103:
+              CRCtriplet(crc, next, -103);
+              /* fallthrough */
+            case 102:
+              CRCtriplet(crc, next, -102);
+              /* fallthrough */
+            case 101:
+              CRCtriplet(crc, next, -101);
+              /* fallthrough */
+            case 100:
+              CRCtriplet(crc, next, -100);
+              /* fallthrough */
+            case 99:
+              CRCtriplet(crc, next, -99);
+              /* fallthrough */
+            case 98:
+              CRCtriplet(crc, next, -98);
+              /* fallthrough */
+            case 97:
+              CRCtriplet(crc, next, -97);
+              /* fallthrough */
+            case 96:
+              CRCtriplet(crc, next, -96);
+              /* fallthrough */
+            case 95:
+              CRCtriplet(crc, next, -95);
+              /* fallthrough */
+            case 94:
+              CRCtriplet(crc, next, -94);
+              /* fallthrough */
+            case 93:
+              CRCtriplet(crc, next, -93);
+              /* fallthrough */
+            case 92:
+              CRCtriplet(crc, next, -92);
+              /* fallthrough */
+            case 91:
+              CRCtriplet(crc, next, -91);
+              /* fallthrough */
+            case 90:
+              CRCtriplet(crc, next, -90);
+              /* fallthrough */
+            case 89:
+              CRCtriplet(crc, next, -89);
+              /* fallthrough */
+            case 88:
+              CRCtriplet(crc, next, -88);
+              /* fallthrough */
+            case 87:
+              CRCtriplet(crc, next, -87);
+              /* fallthrough */
+            case 86:
+              CRCtriplet(crc, next, -86);
+              /* fallthrough */
+            case 85:
+              CRCtriplet(crc, next, -85);
+              /* fallthrough */
+            case 84:
+              CRCtriplet(crc, next, -84);
+              /* fallthrough */
+            case 83:
+              CRCtriplet(crc, next, -83);
+              /* fallthrough */
+            case 82:
+              CRCtriplet(crc, next, -82);
+              /* fallthrough */
+            case 81:
+              CRCtriplet(crc, next, -81);
+              /* fallthrough */
+            case 80:
+              CRCtriplet(crc, next, -80);
+              /* fallthrough */
+            case 79:
+              CRCtriplet(crc, next, -79);
+              /* fallthrough */
+            case 78:
+              CRCtriplet(crc, next, -78);
+              /* fallthrough */
+            case 77:
+              CRCtriplet(crc, next, -77);
+              /* fallthrough */
+            case 76:
+              CRCtriplet(crc, next, -76);
+              /* fallthrough */
+            case 75:
+              CRCtriplet(crc, next, -75);
+              /* fallthrough */
+            case 74:
+              CRCtriplet(crc, next, -74);
+              /* fallthrough */
+            case 73:
+              CRCtriplet(crc, next, -73);
+              /* fallthrough */
+            case 72:
+              CRCtriplet(crc, next, -72);
+              /* fallthrough */
+            case 71:
+              CRCtriplet(crc, next, -71);
+              /* fallthrough */
+            case 70:
+              CRCtriplet(crc, next, -70);
+              /* fallthrough */
+            case 69:
+              CRCtriplet(crc, next, -69);
+              /* fallthrough */
+            case 68:
+              CRCtriplet(crc, next, -68);
+              /* fallthrough */
+            case 67:
+              CRCtriplet(crc, next, -67);
+              /* fallthrough */
+            case 66:
+              CRCtriplet(crc, next, -66);
+              /* fallthrough */
+            case 65:
+              CRCtriplet(crc, next, -65);
+              /* fallthrough */
+            case 64:
+              CRCtriplet(crc, next, -64);
+              /* fallthrough */
+            case 63:
+              CRCtriplet(crc, next, -63);
+              /* fallthrough */
+            case 62:
+              CRCtriplet(crc, next, -62);
+              /* fallthrough */
+            case 61:
+              CRCtriplet(crc, next, -61);
+              /* fallthrough */
+            case 60:
+              CRCtriplet(crc, next, -60);
+              /* fallthrough */
+            case 59:
+              CRCtriplet(crc, next, -59);
+              /* fallthrough */
+            case 58:
+              CRCtriplet(crc, next, -58);
+              /* fallthrough */
+            case 57:
+              CRCtriplet(crc, next, -57);
+              /* fallthrough */
+            case 56:
+              CRCtriplet(crc, next, -56);
+              /* fallthrough */
+            case 55:
+              CRCtriplet(crc, next, -55);
+              /* fallthrough */
+            case 54:
+              CRCtriplet(crc, next, -54);
+              /* fallthrough */
+            case 53:
+              CRCtriplet(crc, next, -53);
+              /* fallthrough */
+            case 52:
+              CRCtriplet(crc, next, -52);
+              /* fallthrough */
+            case 51:
+              CRCtriplet(crc, next, -51);
+              /* fallthrough */
+            case 50:
+              CRCtriplet(crc, next, -50);
+              /* fallthrough */
+            case 49:
+              CRCtriplet(crc, next, -49);
+              /* fallthrough */
+            case 48:
+              CRCtriplet(crc, next, -48);
+              /* fallthrough */
+            case 47:
+              CRCtriplet(crc, next, -47);
+              /* fallthrough */
+            case 46:
+              CRCtriplet(crc, next, -46);
+              /* fallthrough */
+            case 45:
+              CRCtriplet(crc, next, -45);
+              /* fallthrough */
+            case 44:
+              CRCtriplet(crc, next, -44);
+              /* fallthrough */
+            case 43:
+              CRCtriplet(crc, next, -43);
+              /* fallthrough */
+            case 42:
+              CRCtriplet(crc, next, -42);
+              /* fallthrough */
+            case 41:
+              CRCtriplet(crc, next, -41);
+              /* fallthrough */
+            case 40:
+              CRCtriplet(crc, next, -40);
+              /* fallthrough */
+            case 39:
+              CRCtriplet(crc, next, -39);
+              /* fallthrough */
+            case 38:
+              CRCtriplet(crc, next, -38);
+              /* fallthrough */
+            case 37:
+              CRCtriplet(crc, next, -37);
+              /* fallthrough */
+            case 36:
+              CRCtriplet(crc, next, -36);
+              /* fallthrough */
+            case 35:
+              CRCtriplet(crc, next, -35);
+              /* fallthrough */
+            case 34:
+              CRCtriplet(crc, next, -34);
+              /* fallthrough */
+            case 33:
+              CRCtriplet(crc, next, -33);
+              /* fallthrough */
+            case 32:
+              CRCtriplet(crc, next, -32);
+              /* fallthrough */
+            case 31:
+              CRCtriplet(crc, next, -31);
+              /* fallthrough */
+            case 30:
+              CRCtriplet(crc, next, -30);
+              /* fallthrough */
+            case 29:
+              CRCtriplet(crc, next, -29);
+              /* fallthrough */
+            case 28:
+              CRCtriplet(crc, next, -28);
+              /* fallthrough */
+            case 27:
+              CRCtriplet(crc, next, -27);
+              /* fallthrough */
+            case 26:
+              CRCtriplet(crc, next, -26);
+              /* fallthrough */
+            case 25:
+              CRCtriplet(crc, next, -25);
+              /* fallthrough */
+            case 24:
+              CRCtriplet(crc, next, -24);
+              /* fallthrough */
+            case 23:
+              CRCtriplet(crc, next, -23);
+              /* fallthrough */
+            case 22:
+              CRCtriplet(crc, next, -22);
+              /* fallthrough */
+            case 21:
+              CRCtriplet(crc, next, -21);
+              /* fallthrough */
+            case 20:
+              CRCtriplet(crc, next, -20);
+              /* fallthrough */
+            case 19:
+              CRCtriplet(crc, next, -19);
+              /* fallthrough */
+            case 18:
+              CRCtriplet(crc, next, -18);
+              /* fallthrough */
+            case 17:
+              CRCtriplet(crc, next, -17);
+              /* fallthrough */
+            case 16:
+              CRCtriplet(crc, next, -16);
+              /* fallthrough */
+            case 15:
+              CRCtriplet(crc, next, -15);
+              /* fallthrough */
+            case 14:
+              CRCtriplet(crc, next, -14);
+              /* fallthrough */
+            case 13:
+              CRCtriplet(crc, next, -13);
+              /* fallthrough */
+            case 12:
+              CRCtriplet(crc, next, -12);
+              /* fallthrough */
+            case 11:
+              CRCtriplet(crc, next, -11);
+              /* fallthrough */
+            case 10:
+              CRCtriplet(crc, next, -10);
+              /* fallthrough */
+            case 9:
+              CRCtriplet(crc, next, -9);
+              /* fallthrough */
+            case 8:
+              CRCtriplet(crc, next, -8);
+              /* fallthrough */
+            case 7:
+              CRCtriplet(crc, next, -7);
+              /* fallthrough */
+            case 6:
+              CRCtriplet(crc, next, -6);
+              /* fallthrough */
+            case 5:
+              CRCtriplet(crc, next, -5);
+              /* fallthrough */
+            case 4:
+              CRCtriplet(crc, next, -4);
+              /* fallthrough */
+            case 3:
+              CRCtriplet(crc, next, -3);
+              /* fallthrough */
+            case 2:
+              CRCtriplet(crc, next, -2);
+              /* fallthrough */
+            case 1:
+              CRCduplet(crc, next, -1); // the final triplet is actually only 2
+              //{ CombineCRC(); }
+              crc0 = CombineCRC(block_size, crc0, crc1, crc2, next2);
+              if (--n > 0) {
+                crc1 = crc2 = 0;
+                block_size = 128;
+                // points to the first byte of the next block
+                next0 = next2 + 128;
+                next1 = next0 + 128; // from here on all blocks are 128 long
+                next2 = next1 + 128;
+              }
+              /* fallthrough */
+            case 0:;
+          } while (n > 0);
+      }
+      next = (const unsigned char*)next2;
+    }
+    uint64_t count2 = len >> 3; // 216 of less bytes is 27 or less singlets
+    len = len & 7;
+    next += (count2 * 8);
+    switch (count2) {
+      case 27:
+        CRCsinglet(crc0, next, -27 * 8);
+        /* fallthrough */
+      case 26:
+        CRCsinglet(crc0, next, -26 * 8);
+        /* fallthrough */
+      case 25:
+        CRCsinglet(crc0, next, -25 * 8);
+        /* fallthrough */
+      case 24:
+        CRCsinglet(crc0, next, -24 * 8);
+        /* fallthrough */
+      case 23:
+        CRCsinglet(crc0, next, -23 * 8);
+        /* fallthrough */
+      case 22:
+        CRCsinglet(crc0, next, -22 * 8);
+        /* fallthrough */
+      case 21:
+        CRCsinglet(crc0, next, -21 * 8);
+        /* fallthrough */
+      case 20:
+        CRCsinglet(crc0, next, -20 * 8);
+        /* fallthrough */
+      case 19:
+        CRCsinglet(crc0, next, -19 * 8);
+        /* fallthrough */
+      case 18:
+        CRCsinglet(crc0, next, -18 * 8);
+        /* fallthrough */
+      case 17:
+        CRCsinglet(crc0, next, -17 * 8);
+        /* fallthrough */
+      case 16:
+        CRCsinglet(crc0, next, -16 * 8);
+        /* fallthrough */
+      case 15:
+        CRCsinglet(crc0, next, -15 * 8);
+        /* fallthrough */
+      case 14:
+        CRCsinglet(crc0, next, -14 * 8);
+        /* fallthrough */
+      case 13:
+        CRCsinglet(crc0, next, -13 * 8);
+        /* fallthrough */
+      case 12:
+        CRCsinglet(crc0, next, -12 * 8);
+        /* fallthrough */
+      case 11:
+        CRCsinglet(crc0, next, -11 * 8);
+        /* fallthrough */
+      case 10:
+        CRCsinglet(crc0, next, -10 * 8);
+        /* fallthrough */
+      case 9:
+        CRCsinglet(crc0, next, -9 * 8);
+        /* fallthrough */
+      case 8:
+        CRCsinglet(crc0, next, -8 * 8);
+        /* fallthrough */
+      case 7:
+        CRCsinglet(crc0, next, -7 * 8);
+        /* fallthrough */
+      case 6:
+        CRCsinglet(crc0, next, -6 * 8);
+        /* fallthrough */
+      case 5:
+        CRCsinglet(crc0, next, -5 * 8);
+        /* fallthrough */
+      case 4:
+        CRCsinglet(crc0, next, -4 * 8);
+        /* fallthrough */
+      case 3:
+        CRCsinglet(crc0, next, -3 * 8);
+        /* fallthrough */
+      case 2:
+        CRCsinglet(crc0, next, -2 * 8);
+        /* fallthrough */
+      case 1:
+        CRCsinglet(crc0, next, -1 * 8);
+        /* fallthrough */
+      case 0:;
+    }
+  }
+  {
+    align_to_8(len, crc0, next);
+    return (uint32_t)crc0 ^ 0xffffffffu;
+  }
+}
diff --git a/mysys/crc32ieee.cc b/mysys/crc32ieee.cc
index 5f8344b4f9d..bbafa1230f8 100644
--- a/mysys/crc32ieee.cc
+++ b/mysys/crc32ieee.cc
@@ -1,4 +1,4 @@
-/* Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved.
+/* Copyright (c) 2020, 2021, MariaDB
 
    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
@@ -39,25 +39,23 @@ typedef unsigned int (*my_crc32_t)(unsigned int, const void *, size_t);
 
 static my_crc32_t init_crc32()
 {
-  my_crc32_t func= my_crc32_zlib;
 #ifdef HAVE_PCLMUL
   if (crc32_pclmul_enabled())
-    func = crc32_pclmul;
+    return crc32_pclmul;
 #elif defined(__GNUC__) && defined(HAVE_ARMV8_CRC)
   if (crc32_aarch64_available())
-    func= crc32_aarch64;
+    return crc32_aarch64;
 #endif
-  return func;
+  return my_crc32_zlib;
 }
 
 static const my_crc32_t my_checksum_func= init_crc32();
 
-#ifndef __powerpc64__
-/* For powerpc, my_checksum is defined elsewhere.*/
-extern "C" unsigned int my_checksum(unsigned int crc, const void *data, size_t len)
+#ifdef __powerpc64__
+# error "my_checksum() is defined in mysys/crc32/crc32_ppc64.c"
+#endif
+extern "C"
+unsigned int my_checksum(unsigned int crc, const void *data, size_t len)
 {
   return my_checksum_func(crc, data, len);
 }
-#endif
-
-