diff options
Diffstat (limited to 'other-licenses/7zstub/src/C/XzCrc64Opt.c')
-rw-r--r-- | other-licenses/7zstub/src/C/XzCrc64Opt.c | 69 |
1 files changed, 69 insertions, 0 deletions
diff --git a/other-licenses/7zstub/src/C/XzCrc64Opt.c b/other-licenses/7zstub/src/C/XzCrc64Opt.c new file mode 100644 index 000000000..9273465d4 --- /dev/null +++ b/other-licenses/7zstub/src/C/XzCrc64Opt.c @@ -0,0 +1,69 @@ +/* XzCrc64Opt.c -- CRC64 calculation
+2017-06-30 : Igor Pavlov : Public domain */
+
+#include "Precomp.h"
+
+#include "CpuArch.h"
+
+#ifndef MY_CPU_BE
+
+#define CRC64_UPDATE_BYTE_2(crc, b) (table[((crc) ^ (b)) & 0xFF] ^ ((crc) >> 8))
+
+UInt64 MY_FAST_CALL XzCrc64UpdateT4(UInt64 v, const void *data, size_t size, const UInt64 *table)
+{
+ const Byte *p = (const Byte *)data;
+ for (; size > 0 && ((unsigned)(ptrdiff_t)p & 3) != 0; size--, p++)
+ v = CRC64_UPDATE_BYTE_2(v, *p);
+ for (; size >= 4; size -= 4, p += 4)
+ {
+ UInt32 d = (UInt32)v ^ *(const UInt32 *)p;
+ v = (v >> 32)
+ ^ (table + 0x300)[((d ) & 0xFF)]
+ ^ (table + 0x200)[((d >> 8) & 0xFF)]
+ ^ (table + 0x100)[((d >> 16) & 0xFF)]
+ ^ (table + 0x000)[((d >> 24))];
+ }
+ for (; size > 0; size--, p++)
+ v = CRC64_UPDATE_BYTE_2(v, *p);
+ return v;
+}
+
+#endif
+
+
+#ifndef MY_CPU_LE
+
+#define CRC_UINT64_SWAP(v) \
+ ((v >> 56) \
+ | ((v >> 40) & ((UInt64)0xFF << 8)) \
+ | ((v >> 24) & ((UInt64)0xFF << 16)) \
+ | ((v >> 8) & ((UInt64)0xFF << 24)) \
+ | ((v << 8) & ((UInt64)0xFF << 32)) \
+ | ((v << 24) & ((UInt64)0xFF << 40)) \
+ | ((v << 40) & ((UInt64)0xFF << 48)) \
+ | ((v << 56)))
+
+#define CRC64_UPDATE_BYTE_2_BE(crc, b) (table[(Byte)((crc) >> 56) ^ (b)] ^ ((crc) << 8))
+
+UInt64 MY_FAST_CALL XzCrc64UpdateT1_BeT4(UInt64 v, const void *data, size_t size, const UInt64 *table)
+{
+ const Byte *p = (const Byte *)data;
+ table += 0x100;
+ v = CRC_UINT64_SWAP(v);
+ for (; size > 0 && ((unsigned)(ptrdiff_t)p & 3) != 0; size--, p++)
+ v = CRC64_UPDATE_BYTE_2_BE(v, *p);
+ for (; size >= 4; size -= 4, p += 4)
+ {
+ UInt32 d = (UInt32)(v >> 32) ^ *(const UInt32 *)p;
+ v = (v << 32)
+ ^ (table + 0x000)[((d ) & 0xFF)]
+ ^ (table + 0x100)[((d >> 8) & 0xFF)]
+ ^ (table + 0x200)[((d >> 16) & 0xFF)]
+ ^ (table + 0x300)[((d >> 24))];
+ }
+ for (; size > 0; size--, p++)
+ v = CRC64_UPDATE_BYTE_2_BE(v, *p);
+ return CRC_UINT64_SWAP(v);
+}
+
+#endif
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