96 lines
2.6 KiB
C
96 lines
2.6 KiB
C
|
// Copyright (c) 2017 International Business Machines Corp.
|
||
|
|
// All rights reserved.
|
||
|
|
// This source code is licensed under the BSD-style license found in the
|
||
|
|
// LICENSE file in the root directory of this source tree. An additional grant
|
||
|
|
// of patent rights can be found in the PATENTS file in the same directory.
|
||
|
|
// This source code is also licensed under the GPLv2 license found in the
|
||
|
|
// COPYING file in the root directory of this source tree.
|
||
|
|
|
||
|
|
#define CRC_TABLE
|
||
|
|
#include <inttypes.h>
|
||
|
|
#include <stdlib.h>
|
||
|
|
#include <strings.h>
|
||
|
|
#include "util/crc32c_ppc_constants.h"
|
||
|
|
|
||
|
|
#define VMX_ALIGN 16
|
||
|
|
#define VMX_ALIGN_MASK (VMX_ALIGN - 1)
|
||
|
|
|
||
|
|
#ifdef REFLECT
|
||
|
|
static unsigned int crc32_align(unsigned int crc, unsigned char const *p,
|
||
|
|
unsigned long len) {
|
||
|
|
while (len--) crc = crc_table[(crc ^ *p++) & 0xff] ^ (crc >> 8);
|
||
|
|
return crc;
|
||
|
|
}
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#ifdef HAVE_POWER8
|
||
|
|
unsigned int __crc32_vpmsum(unsigned int crc, unsigned char const *p,
|
||
|
|
unsigned long len);
|
||
|
|
|
||
|
|
static uint32_t crc32_vpmsum(uint32_t crc, unsigned char const *data,
|
||
|
|
unsigned len) {
|
||
|
|
unsigned int prealign;
|
||
|
|
unsigned int tail;
|
||
|
|
|
||
|
|
#ifdef CRC_XOR
|
||
|
|
crc ^= 0xffffffff;
|
||
|
|
#endif
|
||
|
|
|
||
|
|
if (len < VMX_ALIGN + VMX_ALIGN_MASK) {
|
||
|
|
crc = crc32_align(crc, data, (unsigned long)len);
|
||
|
|
goto out;
|
||
|
|
}
|
||
|
|
|
||
|
|
if ((unsigned long)data & VMX_ALIGN_MASK) {
|
||
|
|
prealign = VMX_ALIGN - ((unsigned long)data & VMX_ALIGN_MASK);
|
||
|
|
crc = crc32_align(crc, data, prealign);
|
||
|
|
len -= prealign;
|
||
|
|
data += prealign;
|
||
|
|
}
|
||
|
|
|
||
|
|
crc = __crc32_vpmsum(crc, data, (unsigned long)len & ~VMX_ALIGN_MASK);
|
||
|
|
|
||
|
|
tail = len & VMX_ALIGN_MASK;
|
||
|
|
if (tail) {
|
||
|
|
data += len & ~VMX_ALIGN_MASK;
|
||
|
|
crc = crc32_align(crc, data, tail);
|
||
|
|
}
|
||
|
|
|
||
|
|
out:
|
||
|
|
#ifdef CRC_XOR
|
||
|
|
crc ^= 0xffffffff;
|
||
|
|
#endif
|
||
|
|
|
||
|
|
return crc;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* This wrapper function works around the fact that crc32_vpmsum
|
||
|
|
* does not gracefully handle the case where the data pointer is NULL. There
|
||
|
|
* may be room for performance improvement here.
|
||
|
|
*/
|
||
|
|
uint32_t crc32c_ppc(uint32_t crc, unsigned char const *data, unsigned len) {
|
||
|
|
unsigned char *buf2;
|
||
|
|
|
||
|
|
if (!data) {
|
||
|
|
buf2 = (unsigned char *)malloc(len);
|
||
|
|
bzero(buf2, len);
|
||
|
|
crc = crc32_vpmsum(crc, buf2, len);
|
||
|
|
free(buf2);
|
||
|
|
} else {
|
||
|
|
crc = crc32_vpmsum(crc, data, (unsigned long)len);
|
||
|
|
}
|
||
|
|
return crc;
|
||
|
|
}
|
||
|
|
|
||
|
|
#else /* HAVE_POWER8 */
|
||
|
|
|
||
|
|
/* This symbol has to exist on non-ppc architectures (and on legacy
|
||
|
|
* ppc systems using power7 or below) in order to compile properly
|
||
|
|
* there, even though it won't be called.
|
||
|
|
*/
|
||
|
|
uint32_t crc32c_ppc(uint32_t crc, unsigned char const *data, unsigned len) {
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
#endif /* HAVE_POWER8 */
|