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#include <my_global.h>
#include <string.h>
#include <stdint.h>
static int pmull_supported;
#if defined(HAVE_ARMV8_CRC)
#if defined(__APPLE__)
#include <sys/sysctl.h>
int crc32_aarch64_available(void)
{
int ret;
size_t len = sizeof(ret);
if (sysctlbyname("hw.optional.armv8_crc32", &ret, &len, NULL, 0) == -1)
return 0;
return ret;
}
const char *crc32c_aarch64_available(void)
{
if (crc32_aarch64_available() == 0)
return NULL;
pmull_supported = 1;
return "Using ARMv8 crc32 + pmull instructions";
}
#else
#include <sys/auxv.h>
#if defined(__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
#ifndef HWCAP_CRC32
# define HWCAP_CRC32 (1 << 7)
#endif
#ifndef HWCAP_PMULL
# define HWCAP_PMULL (1 << 4)
#endif
/* ARM made crc32 default from ARMv8.1 but optional in ARMv8A
* Runtime check API.
*/
int crc32_aarch64_available(void)
{
unsigned long auxv= getauxval(AT_HWCAP);
return (auxv & HWCAP_CRC32) != 0;
}
const char *crc32c_aarch64_available(void)
{
unsigned long auxv= getauxval(AT_HWCAP);
if (!(auxv & HWCAP_CRC32))
return NULL;
pmull_supported= (auxv & HWCAP_PMULL) != 0;
if (pmull_supported)
return "Using ARMv8 crc32 + pmull instructions";
else
return "Using ARMv8 crc32 instructions";
}
#endif /* __APPLE__ */
#endif /* HAVE_ARMV8_CRC */
#ifndef HAVE_ARMV8_CRC_CRYPTO_INTRINSICS
/* Request crc extension capabilities from the assembler */
asm(".arch_extension crc");
# ifdef HAVE_ARMV8_CRYPTO
/* crypto extension */
asm(".arch_extension crypto");
# endif
#define CRC32CX(crc, value) __asm__("crc32cx %w[c], %w[c], %x[v]":[c]"+r"(crc):[v]"r"(value))
#define CRC32CW(crc, value) __asm__("crc32cw %w[c], %w[c], %w[v]":[c]"+r"(crc):[v]"r"(value))
#define CRC32CH(crc, value) __asm__("crc32ch %w[c], %w[c], %w[v]":[c]"+r"(crc):[v]"r"(value))
#define CRC32CB(crc, value) __asm__("crc32cb %w[c], %w[c], %w[v]":[c]"+r"(crc):[v]"r"(value))
#define CRC32X(crc, value) __asm__("crc32x %w[c], %w[c], %x[v]":[c]"+r"(crc):[v]"r"(value))
#define CRC32W(crc, value) __asm__("crc32w %w[c], %w[c], %w[v]":[c]"+r"(crc):[v]"r"(value))
#define CRC32H(crc, value) __asm__("crc32h %w[c], %w[c], %w[v]":[c]"+r"(crc):[v]"r"(value))
#define CRC32B(crc, value) __asm__("crc32b %w[c], %w[c], %w[v]":[c]"+r"(crc):[v]"r"(value))
#define CRC32C3X8(buffer, ITR) \
__asm__("crc32cx %w[c1], %w[c1], %x[v]":[c1]"+r"(crc1):[v]"r"(*((const uint64_t *)buffer + 42*1 + (ITR))));\
__asm__("crc32cx %w[c2], %w[c2], %x[v]":[c2]"+r"(crc2):[v]"r"(*((const uint64_t *)buffer + 42*2 + (ITR))));\
__asm__("crc32cx %w[c0], %w[c0], %x[v]":[c0]"+r"(crc0):[v]"r"(*((const uint64_t *)buffer + 42*0 + (ITR))));
#else /* HAVE_ARMV8_CRC_CRYPTO_INTRINSICS */
/* Intrinsics header*/
#include <arm_acle.h>
#include <arm_neon.h>
#define CRC32CX(crc, value) (crc) = __crc32cd((crc), (value))
#define CRC32CW(crc, value) (crc) = __crc32cw((crc), (value))
#define CRC32CH(crc, value) (crc) = __crc32ch((crc), (value))
#define CRC32CB(crc, value) (crc) = __crc32cb((crc), (value))
#define CRC32X(crc, value) (crc) = __crc32d((crc), (value))
#define CRC32W(crc, value) (crc) = __crc32w((crc), (value))
#define CRC32H(crc, value) (crc) = __crc32h((crc), (value))
#define CRC32B(crc, value) (crc) = __crc32b((crc), (value))
#define CRC32C3X8(buffer, ITR) \
crc1 = __crc32cd(crc1, *((const uint64_t *)buffer + 42*1 + (ITR)));\
crc2 = __crc32cd(crc2, *((const uint64_t *)buffer + 42*2 + (ITR)));\
crc0 = __crc32cd(crc0, *((const uint64_t *)buffer + 42*0 + (ITR)));
#endif /* HAVE_ARMV8_CRC_CRYPTO_INTRINSICS */
#define CRC32C7X3X8(buffer, ITR) do {\
CRC32C3X8(buffer, ((ITR) * 7 + 0)) \
CRC32C3X8(buffer, ((ITR) * 7 + 1)) \
CRC32C3X8(buffer, ((ITR) * 7 + 2)) \
CRC32C3X8(buffer, ((ITR) * 7 + 3)) \
CRC32C3X8(buffer, ((ITR) * 7 + 4)) \
CRC32C3X8(buffer, ((ITR) * 7 + 5)) \
CRC32C3X8(buffer, ((ITR) * 7 + 6)) \
} while(0)
#define PREF4X64L1(buffer, PREF_OFFSET, ITR) \
__asm__("PRFM PLDL1KEEP, [%x[v],%[c]]"::[v]"r"(buffer), [c]"I"((PREF_OFFSET) + ((ITR) + 0)*64));\
__asm__("PRFM PLDL1KEEP, [%x[v],%[c]]"::[v]"r"(buffer), [c]"I"((PREF_OFFSET) + ((ITR) + 1)*64));\
__asm__("PRFM PLDL1KEEP, [%x[v],%[c]]"::[v]"r"(buffer), [c]"I"((PREF_OFFSET) + ((ITR) + 2)*64));\
__asm__("PRFM PLDL1KEEP, [%x[v],%[c]]"::[v]"r"(buffer), [c]"I"((PREF_OFFSET) + ((ITR) + 3)*64));
#define PREF1KL1(buffer, PREF_OFFSET) \
PREF4X64L1(buffer,(PREF_OFFSET), 0) \
PREF4X64L1(buffer,(PREF_OFFSET), 4) \
PREF4X64L1(buffer,(PREF_OFFSET), 8) \
PREF4X64L1(buffer,(PREF_OFFSET), 12)
#define PREF4X64L2(buffer, PREF_OFFSET, ITR) \
__asm__("PRFM PLDL2KEEP, [%x[v],%[c]]"::[v]"r"(buffer), [c]"I"((PREF_OFFSET) + ((ITR) + 0)*64));\
__asm__("PRFM PLDL2KEEP, [%x[v],%[c]]"::[v]"r"(buffer), [c]"I"((PREF_OFFSET) + ((ITR) + 1)*64));\
__asm__("PRFM PLDL2KEEP, [%x[v],%[c]]"::[v]"r"(buffer), [c]"I"((PREF_OFFSET) + ((ITR) + 2)*64));\
__asm__("PRFM PLDL2KEEP, [%x[v],%[c]]"::[v]"r"(buffer), [c]"I"((PREF_OFFSET) + ((ITR) + 3)*64));
#define PREF1KL2(buffer, PREF_OFFSET) \
PREF4X64L2(buffer,(PREF_OFFSET), 0) \
PREF4X64L2(buffer,(PREF_OFFSET), 4) \
PREF4X64L2(buffer,(PREF_OFFSET), 8) \
PREF4X64L2(buffer,(PREF_OFFSET), 12)
uint32_t crc32c_aarch64(uint32_t crc, const unsigned char *buffer, uint64_t len)
{
uint32_t crc0, crc1, crc2;
int64_t length= (int64_t)len;
crc^= 0xffffffff;
/* Pmull runtime check here.
* Raspberry Pi 4 supports crc32 but doesn't support pmull (MDEV-23030).
*
* Consider the condition that the target platform does support hardware crc32
* but not support PMULL. In this condition, it should leverage the aarch64
* crc32 instruction (__crc32c) and just only skip parallel computation (pmull/vmull)
* rather than skip all hardware crc32 instruction of computation.
*/
if (pmull_supported)
{
/* The following Macro (HAVE_ARMV8_CRYPTO) is used for compiling check */
#ifdef HAVE_ARMV8_CRYPTO
/* Crypto extension Support
* Parallel computation with 1024 Bytes (per block)
* Intrinsics Support
*/
# ifdef HAVE_ARMV8_CRC_CRYPTO_INTRINSICS
const poly64_t k1= 0xe417f38a, k2= 0x8f158014;
uint64_t t0, t1;
/* Process per block size of 1024 Bytes
* A block size = 8 + 42*3*sizeof(uint64_t) + 8
*/
while ((length-= 1024) >= 0)
{
/* Prefetch 3*1024 data for avoiding L2 cache miss */
PREF1KL2(buffer, 1024*3);
/* Do first 8 bytes here for better pipelining */
crc0= __crc32cd(crc, *(const uint64_t *)buffer);
crc1= 0;
crc2= 0;
buffer+= sizeof(uint64_t);
/* Process block inline
* Process crc0 last to avoid dependency with above
*/
CRC32C7X3X8(buffer, 0);
CRC32C7X3X8(buffer, 1);
CRC32C7X3X8(buffer, 2);
CRC32C7X3X8(buffer, 3);
CRC32C7X3X8(buffer, 4);
CRC32C7X3X8(buffer, 5);
buffer+= 42*3*sizeof(uint64_t);
/* Prefetch data for following block to avoid L1 cache miss */
PREF1KL1(buffer, 1024);
/* Last 8 bytes
* Merge crc0 and crc1 into crc2
* crc1 multiply by K2
* crc0 multiply by K1
*/
t1= (uint64_t)vmull_p64(crc1, k2);
t0= (uint64_t)vmull_p64(crc0, k1);
crc= __crc32cd(crc2, *(const uint64_t *)buffer);
crc1= __crc32cd(0, t1);
crc^= crc1;
crc0= __crc32cd(0, t0);
crc^= crc0;
buffer+= sizeof(uint64_t);
}
# else /* HAVE_ARMV8_CRC_CRYPTO_INTRINSICS */
/*No intrinsics*/
__asm__("mov x16, #0xf38a \n\t"
"movk x16, #0xe417, lsl 16 \n\t"
"mov v1.2d[0], x16 \n\t"
"mov x16, #0x8014 \n\t"
"movk x16, #0x8f15, lsl 16 \n\t"
"mov v0.2d[0], x16 \n\t"
:::"x16");
while ((length-= 1024) >= 0)
{
PREF1KL2(buffer, 1024*3);
__asm__("crc32cx %w[c0], %w[c], %x[v]\n\t"
:[c0]"=r"(crc0):[c]"r"(crc), [v]"r"(*(const uint64_t *)buffer):);
crc1= 0;
crc2= 0;
buffer+= sizeof(uint64_t);
CRC32C7X3X8(buffer, 0);
CRC32C7X3X8(buffer, 1);
CRC32C7X3X8(buffer, 2);
CRC32C7X3X8(buffer, 3);
CRC32C7X3X8(buffer, 4);
CRC32C7X3X8(buffer, 5);
buffer+= 42*3*sizeof(uint64_t);
PREF1KL1(buffer, 1024);
__asm__("mov v2.2d[0], %x[c1] \n\t"
"pmull v2.1q, v2.1d, v0.1d \n\t"
"mov v3.2d[0], %x[c0] \n\t"
"pmull v3.1q, v3.1d, v1.1d \n\t"
"crc32cx %w[c], %w[c2], %x[v] \n\t"
"mov %x[c1], v2.2d[0] \n\t"
"crc32cx %w[c1], wzr, %x[c1] \n\t"
"eor %w[c], %w[c], %w[c1] \n\t"
"mov %x[c0], v3.2d[0] \n\t"
"crc32cx %w[c0], wzr, %x[c0] \n\t"
"eor %w[c], %w[c], %w[c0] \n\t"
:[c1]"+r"(crc1), [c0]"+r"(crc0), [c2]"+r"(crc2), [c]"+r"(crc)
:[v]"r"(*((const uint64_t *)buffer)));
buffer+= sizeof(uint64_t);
}
# endif /* HAVE_ARMV8_CRC_CRYPTO_INTRINSICS */
/* Done if Input data size is aligned with 1024 */
if (!(length+= 1024))
return ~crc;
#endif /* HAVE_ARMV8_CRYPTO */
} // end if pmull_supported
while ((length-= sizeof(uint64_t)) >= 0)
{
CRC32CX(crc, *(uint64_t *)buffer);
buffer+= sizeof(uint64_t);
}
/* The following is more efficient than the straight loop */
if (length & sizeof(uint32_t))
{
CRC32CW(crc, *(uint32_t *)buffer);
buffer+= sizeof(uint32_t);
}
if (length & sizeof(uint16_t))
{
CRC32CH(crc, *(uint16_t *)buffer);
buffer+= sizeof(uint16_t);
}
if (length & sizeof(uint8_t))
CRC32CB(crc, *buffer);
return ~crc;
}
/* 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
using 8/1 combination.
Based on micro-benchmark testing we found that Approach-2 works best especially
given small chunk of variable data. */
unsigned int crc32_aarch64(unsigned int crc, const void *buf, size_t len)
{
const uint8_t *buf1= buf;
const uint64_t *buf8= (const uint64_t *) (((uintptr_t) buf + 7) & ~7);
crc= ~crc;
/* if start pointer is not 8 bytes aligned */
while ((buf1 != (const uint8_t *) buf8) && len)
{
CRC32B(crc, *buf1++);
len--;
}
for (; len >= 8; len-= 8)
CRC32X(crc, *buf8++);
buf1= (const uint8_t *) buf8;
while (len--)
CRC32B(crc, *buf1++);
return ~crc;
}
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