crc32 compatibility on Windows on ARM64

Author: coneco-cy

mysys/crc32/crc32_arm64.c

@@ -4,31 +4,38 @@
 #include <stddef.h>
 
 typedef unsigned (*my_crc32_t)(unsigned, const void *, size_t);
+unsigned crc32_aarch64(unsigned, const void *, size_t);
 
 #ifdef HAVE_ARMV8_CRC
 
-#ifdef _WIN32
-#include <windows.h>
+# ifdef HAVE_ARMV8_CRYPTO
+static unsigned crc32c_aarch64_pmull(unsigned, const void *, size_t);
+# endif
+
+# ifdef _WIN32
+#  include <windows.h>
+#  ifdef __clang__
+#   include <arm_acle.h>
+#   include <arm_neon.h>
+# endif
 int crc32_aarch64_available(void)
 {
   return IsProcessorFeaturePresent(PF_ARM_V8_CRC32_INSTRUCTIONS_AVAILABLE);
 }
 
-const char *crc32c_aarch64_available(void)
+unsigned crc32c_aarch64(unsigned, const void *, size_t);
+
+my_crc32_t crc32c_aarch64_available(void)
 {
   if (crc32_aarch64_available() == 0)
     return NULL;
   /* TODO : pmull seems supported, but does not compile*/
-  return "Using ARMv8 crc32 instructions";
+  return crc32c_aarch64;
 }
-#endif /* _WIN32 */
 
-#ifdef HAVE_ARMV8_CRYPTO
-static unsigned crc32c_aarch64_pmull(unsigned, const void *, size_t);
-# endif
-
-# ifdef __APPLE__
-#  include <sys/sysctl.h>
+# else /* _WIN32 */
+#  ifdef __APPLE__
+#   include <sys/sysctl.h>
 
 int crc32_aarch64_available(void)
 {
@@ -41,34 +48,34 @@ int crc32_aarch64_available(void)
 
 my_crc32_t crc32c_aarch64_available(void)
 {
-# ifdef HAVE_ARMV8_CRYPTO
+#   ifdef HAVE_ARMV8_CRYPTO
   if (crc32_aarch64_available())
     return crc32c_aarch64_pmull;
-# endif
+#   endif
   return NULL;
 }
 
-# else /* __APPLE__ */
-#  include <sys/auxv.h>
-#  ifdef __FreeBSD__
+#  else /* __APPLE__ */
+#   include <sys/auxv.h>
+#   ifdef __FreeBSD__
 static unsigned long getauxval(unsigned int key)
 {
   unsigned long val;
   if (elf_aux_info(key, (void *)&val, (int)sizeof(val) != 0))
     return 0ul;
   return val;
 }
-#  else
-#   include <asm/hwcap.h>
-#  endif
+#   else
+#    include <asm/hwcap.h>
+#   endif
 
-#  ifndef HWCAP_CRC32
-#   define HWCAP_CRC32 (1 << 7)
-#  endif
+#   ifndef HWCAP_CRC32
+#    define HWCAP_CRC32 (1 << 7)
+#   endif
 
-#  ifndef HWCAP_PMULL
-#   define HWCAP_PMULL (1 << 4)
-#  endif
+#   ifndef HWCAP_PMULL
+#    define HWCAP_PMULL (1 << 4)
+#   endif
 
 /* ARM made crc32 default from ARMv8.1 but optional in ARMv8A
  * Runtime check API.
@@ -78,24 +85,25 @@ int crc32_aarch64_available(void)
   unsigned long auxv= getauxval(AT_HWCAP);
   return (auxv & HWCAP_CRC32) != 0;
 }
-# endif /* __APPLE__ */
+#  endif /* __APPLE__ */
 
-# ifndef __APPLE__
+#  ifndef __APPLE__
 static unsigned crc32c_aarch64(unsigned, const void *, size_t);
 
 my_crc32_t crc32c_aarch64_available(void)
 {
   unsigned long auxv= getauxval(AT_HWCAP);
   if (!(auxv & HWCAP_CRC32))
     return NULL;
-#  ifdef HAVE_ARMV8_CRYPTO
+#   ifdef HAVE_ARMV8_CRYPTO
   /* Raspberry Pi 4 supports crc32 but doesn't support pmull (MDEV-23030). */
   if (auxv & HWCAP_PMULL)
     return crc32c_aarch64_pmull;
-#  endif
+#   endif
   return crc32c_aarch64;
 }
-# endif /* __APPLE__ */
+#  endif /* __APPLE__ */
+# endif /* _WIN32 */
 
 const char *crc32c_aarch64_impl(my_crc32_t c)
 {
@@ -370,7 +378,7 @@ static unsigned crc32c_aarch64_pmull(unsigned crc, const void *buf, size_t len)
 /* There are multiple approaches to calculate crc.
 Approach-1: Process 8 bytes then 4 bytes then 2 bytes and then 1 bytes
 Approach-2: Process 8 bytes and remaining workload using 1 bytes
-Apporach-3: Process 64 bytes at once by issuing 8 crc call and remaining
+Approach-3: Process 64 bytes at once by issuing 8 crc call and remaining
             using 8/1 combination.
 
 Based on micro-benchmark testing we found that Approach-2 works best especially