mariadb/mysys/crc32/crc32c_x86.cc
Marko Mäkelä 232d7a5e2d MDEV-34565: SIGILL due to OS not supporting AVX512
It is not sufficient to check that the CPU supports the necessary
instructions. Also the operating system (or virtual machine hypervisor)
must enable all the AVX registers to be saved and restored on a
context switch.

Because clang 8 does not support the compiler intrinsic _xgetbv()
we will require clang 9 or later for enabling the use of VPCLMULQDQ
and the related AVX512 features.
2024-07-29 10:58:09 +03:00

470 lines
14 KiB
C++

/* Copyright (c) 2024, MariaDB plc
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 */
#include <my_global.h>
#include <cstddef>
#include <cstdint>
#ifdef _MSC_VER
# include <intrin.h>
# if 0 /* So far, we have no environment where this could be tested. */
# define USE_VPCLMULQDQ /* nothing */
# endif
#else
# include <cpuid.h>
# ifdef __APPLE__ /* AVX512 states are not enabled in XCR0 */
# elif __GNUC__ >= 14 || (defined __clang_major__ && __clang_major__ >= 18)
# define TARGET "pclmul,evex512,avx512f,avx512dq,avx512bw,avx512vl,vpclmulqdq"
# define USE_VPCLMULQDQ __attribute__((target(TARGET)))
# elif __GNUC__ >= 11 || (defined __clang_major__ && __clang_major__ >= 9)
/* clang 8 does not support _xgetbv(), which we also need */
# define TARGET "pclmul,avx512f,avx512dq,avx512bw,avx512vl,vpclmulqdq"
# define USE_VPCLMULQDQ __attribute__((target(TARGET)))
# endif
#endif
extern "C" unsigned crc32c_sse42(unsigned crc, const void* buf, size_t size);
constexpr uint32_t cpuid_ecx_SSE42= 1U << 20;
constexpr uint32_t cpuid_ecx_SSE42_AND_PCLMUL= cpuid_ecx_SSE42 | 1U << 1;
constexpr uint32_t cpuid_ecx_XSAVE= 1U << 26;
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;
#elif defined _MSC_VER
int regs[4];
__cpuid(regs, 1);
return regs[2];
#else
# error "unknown compiler"
#endif
}
typedef uint32_t (*my_crc32_t)(uint32_t, const void *, size_t);
extern "C" uint32_t crc32_pclmul(uint32_t, const void *, size_t);
extern "C" uint32_t crc32c_3way(uint32_t, const void *, size_t);
#ifdef USE_VPCLMULQDQ
# include <immintrin.h>
# ifdef _MSC_VER
/* MSVC does not seem to define this intrinsic for vmovdqa */
# define _mm_load_epi32(x) *reinterpret_cast<const __m128i*>(x)
# endif
/*
This implementation is based on
crc32_by16_vclmul_avx512 and crc32_refl_by16_vclmul_avx512
in https://github.com/intel/intel-ipsec-mb/ with some optimizations.
The // comments in crc32_avx512() correspond to assembler labels.
*/
/** table of constants corresponding to a CRC polynomial up to degree 32 */
struct alignas(64) crc32_tab
{
const uint64_t b2048[2], b1024[2];
alignas(64) const uint64_t b896[6]; /* includes b786, b640 */
const uint64_t b512[2];
const uint64_t b384[2], b256[2], b128[2], zeropad_for_b384[2];
const uint64_t b64[2], b32[2];
};
/** ISO 3309 CRC-32 (reflected polynomial 0x04C11DB7); zlib crc32() */
static const crc32_tab refl32 = {
{ 0x00000000e95c1271, 0x00000000ce3371cb },
{ 0x00000000910eeec1, 0x0000000033fff533 },
{ 0x000000000cbec0ed, 0x0000000031f8303f,
0x0000000057c54819, 0x00000000df068dc2,
0x00000000ae0b5394, 0x000000001c279815 },
{ 0x000000001d9513d7, 0x000000008f352d95 },
{ 0x00000000af449247, 0x000000003db1ecdc },
{ 0x0000000081256527, 0x00000000f1da05aa },
{ 0x00000000ccaa009e, 0x00000000ae689191 },
{ 0, 0 },
{ 0x00000000ccaa009e, 0x00000000b8bc6765 },
{ 0x00000001f7011640, 0x00000001db710640 }
};
/** Castagnoli CRC-32C (reflected polynomial 0x1EDC6F41) */
static const crc32_tab refl32c = {
{ 0x00000000b9e02b86, 0x00000000dcb17aa4 },
{ 0x000000000d3b6092, 0x000000006992cea2 },
{ 0x0000000047db8317, 0x000000002ad91c30,
0x000000000715ce53, 0x00000000c49f4f67,
0x0000000039d3b296, 0x00000000083a6eec },
{ 0x000000009e4addf8, 0x00000000740eef02 },
{ 0x00000000ddc0152b, 0x000000001c291d04 },
{ 0x00000000ba4fc28e, 0x000000003da6d0cb },
{ 0x00000000493c7d27, 0x00000000f20c0dfe },
{ 0, 0 },
{ 0x00000000493c7d27, 0x00000000dd45aab8 },
{ 0x00000000dea713f0, 0x0000000105ec76f0 }
};
/** Some ternary functions */
class ternary
{
static constexpr uint8_t A = 0b11110000;
static constexpr uint8_t B = 0b11001100;
static constexpr uint8_t C = 0b10101010;
public:
static constexpr uint8_t XOR3 = A ^ B ^ C;
static constexpr uint8_t XNOR3 = uint8_t(~(A ^ B ^ C));
static constexpr uint8_t XOR2_AND = (A ^ B) & C;
};
USE_VPCLMULQDQ
/** @return a^b^c */
static inline __m128i xor3_128(__m128i a, __m128i b, __m128i c)
{
return _mm_ternarylogic_epi64(a, b, c, ternary::XOR3);
}
USE_VPCLMULQDQ
/** @return ~(a^b^c) */
static inline __m128i xnor3_128(__m128i a, __m128i b, __m128i c)
{
return _mm_ternarylogic_epi64(a, b, c, ternary::XNOR3);
}
USE_VPCLMULQDQ
/** @return a^b^c */
static inline __m512i xor3_512(__m512i a, __m512i b, __m512i c)
{
return _mm512_ternarylogic_epi64(a, b, c, ternary::XOR3);
}
USE_VPCLMULQDQ
/** @return (a^b)&c */
static inline __m128i xor2_and_128(__m128i a, __m128i b, __m128i c)
{
return _mm_ternarylogic_epi64(a, b, c, ternary::XOR2_AND);
}
USE_VPCLMULQDQ
/** Load 64 bytes */
static inline __m512i load512(const char *b) { return _mm512_loadu_epi8(b); }
USE_VPCLMULQDQ
/** Load 16 bytes */
static inline __m128i load128(const char *b) { return _mm_loadu_epi64(b); }
/** Combine 512 data bits with CRC */
USE_VPCLMULQDQ
static inline __m512i combine512(__m512i a, __m512i tab, __m512i b)
{
return xor3_512(b, _mm512_clmulepi64_epi128(a, tab, 0x01),
_mm512_clmulepi64_epi128(a, tab, 0x10));
}
# define xor512(a, b) _mm512_xor_epi64(a, b)
# define xor256(a, b) _mm256_xor_epi64(a, b)
# define xor128(a, b) _mm_xor_epi64(a, b)
# define and128(a, b) _mm_and_si128(a, b)
template<uint8_t bits> USE_VPCLMULQDQ
/** Pick and zero-extend 128 bits of a 512-bit vector (vextracti32x4) */
static inline __m512i extract512_128(__m512i a)
{
static_assert(bits <= 3, "usage");
return _mm512_zextsi128_si512(_mm512_extracti64x2_epi64(a, bits));
}
alignas(16) static const uint64_t shuffle128[4] = {
0x8786858483828100, 0x8f8e8d8c8b8a8988,
0x0706050403020100, 0x000e0d0c0b0a0908
};
static const __mmask16 size_mask[16] = {
0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff,
0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff
};
alignas(16) static const uint64_t shift128[4] = {
0x8786858483828100, 0x8f8e8d8c8b8a8988,
0x0706050403020100, 0x000e0d0c0b0a0908
};
static const char shift_1_to_3_reflect[7 + 11] = {
-1, -1, -1, -1, -1, -1, -1,
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10
};
USE_VPCLMULQDQ
static unsigned crc32_avx512(unsigned crc, const char *buf, size_t size,
const crc32_tab &tab)
{
const __m512i crc_in = _mm512_castsi128_si512(_mm_cvtsi32_si128(~crc)),
b512 = _mm512_broadcast_i32x4(_mm_load_epi32(tab.b512));
__m128i crc_out;
__m512i lo;
if (size >= 256) {
lo = xor512(load512(buf), crc_in);
__m512i l1 = load512(buf + 64);
const __m512i b1024 = _mm512_broadcast_i32x4(_mm_load_epi32(&tab.b1024));
size -= 256;
if (size >= 256) {
__m512i h0 = load512(buf + 128),
hi = load512(buf + 192);
const __m512i b2048 = _mm512_broadcast_i32x4(_mm_load_epi32(&tab.b2048));
size -= 256;
do {
buf += 256;
lo = combine512(lo, b2048, load512(buf));
l1 = combine512(l1, b2048, load512(buf + 64));
h0 = combine512(h0, b2048, load512(buf + 128));
hi = combine512(hi, b2048, load512(buf + 192));
size -= 256;
} while (ssize_t(size) >= 0);
buf += 256;
lo = combine512(lo, b1024, h0);
l1 = combine512(l1, b1024, hi);
size += 128;
} else {
do {
buf += 128;
lo = combine512(lo, b1024, load512(buf));
l1 = combine512(l1, b1024, load512(buf + 64));
size -= 128;
} while (ssize_t(size) >= 0);
buf += 128;
}
if (ssize_t(size) >= -64) {
size += 128;
lo = combine512(lo, b512, l1);
goto fold_64_B_loop;
}
const __m512i
b896 = _mm512_load_epi32(&tab.b896),
b384 = _mm512_load_epi32(&tab.b384);
__m512i c4 = xor3_512(_mm512_clmulepi64_epi128(lo, b896, 1),
_mm512_clmulepi64_epi128(lo, b896, 0x10),
_mm512_clmulepi64_epi128(l1, b384, 1));
c4 = xor3_512(c4, _mm512_clmulepi64_epi128(l1, b384, 0x10),
extract512_128<3>(l1));
__m256i c2 =
_mm512_castsi512_si256(_mm512_shuffle_i64x2(c4, c4, 0b01001110));
c2 = xor256(c2, _mm512_castsi512_si256(c4));
crc_out = xor128(_mm256_extracti64x2_epi64(c2, 1),
_mm256_castsi256_si128(c2));
size += 128 - 16;
goto final_reduction;
}
__m128i b;
// less_than_256
if (size >= 32) {
if (size >= 64) {
lo = xor512(load512(buf), crc_in);
while (buf += 64, (size -= 64) >= 64)
fold_64_B_loop:
lo = combine512(lo, b512, load512(buf));
// reduce_64B
const __m512i b384 = _mm512_load_epi32(&tab.b384);
__m512i crc512 =
xor3_512(_mm512_clmulepi64_epi128(lo, b384, 1),
_mm512_clmulepi64_epi128(lo, b384, 0x10),
extract512_128<3>(lo));
crc512 =
xor512(crc512, _mm512_shuffle_i64x2(crc512, crc512, 0b01001110));
const __m256i crc256 = _mm512_castsi512_si256(crc512);
crc_out = xor128(_mm256_extracti64x2_epi64(crc256, 1),
_mm256_castsi256_si128(crc256));
size -= 16;
} else {
// less_than_64
crc_out = xor128(load128(buf),
_mm512_castsi512_si128(crc_in));
buf += 16;
size -= 32;
}
final_reduction:
b = _mm_load_epi32(&tab.b128);
while (ssize_t(size) >= 0) {
// reduction_loop_16B
crc_out = xor3_128(load128(buf),
_mm_clmulepi64_si128(crc_out, b, 1),
_mm_clmulepi64_si128(crc_out, b, 0x10));
buf += 16;
size -= 16;
}
// final_reduction_for_128
size += 16;
if (size) {
get_last_two_xmms:
const __m128i crc2 = crc_out, d = load128(buf + ssize_t(size) - 16);
__m128i S = load128(reinterpret_cast<const char*>(shuffle128) + size);
crc_out = _mm_shuffle_epi8(crc_out, S);
S = xor128(S, _mm_set1_epi32(0x80808080));
crc_out = xor3_128(_mm_blendv_epi8(_mm_shuffle_epi8(crc2, S), d, S),
_mm_clmulepi64_si128(crc_out, b, 1),
_mm_clmulepi64_si128(crc_out, b, 0x10));
}
done_128:
__m128i crc_tmp;
b = _mm_load_epi32(&tab.b64);
crc_tmp = xor128(_mm_clmulepi64_si128(crc_out, b, 0x00),
_mm_srli_si128(crc_out, 8));
crc_out = _mm_slli_si128(crc_tmp, 4);
crc_out = _mm_clmulepi64_si128(crc_out, b, 0x10);
crc_out = xor128(crc_out, crc_tmp);
barrett:
b = _mm_load_epi32(&tab.b32);
crc_tmp = crc_out;
crc_out = and128(crc_out, _mm_set_epi64x(~0ULL, ~0xFFFFFFFFULL));
crc_out = _mm_clmulepi64_si128(crc_out, b, 0);
crc_out = xor2_and_128(crc_out, crc_tmp, _mm_set_epi64x(0, ~0ULL));
crc_out = xnor3_128(crc_out, crc_tmp,
_mm_clmulepi64_si128(crc_out, b, 0x10));
return _mm_extract_epi32(crc_out, 2);
} else {
// less_than_32
if (size > 0) {
if (size > 16) {
crc_out = xor128(load128(buf),
_mm512_castsi512_si128(crc_in));
buf += 16;
size -= 16;
b = _mm_load_epi32(&tab.b128);
goto get_last_two_xmms;
} else if (size < 16) {
crc_out = _mm_maskz_loadu_epi8(size_mask[size - 1], buf);
crc_out = xor128(crc_out, _mm512_castsi512_si128(crc_in));
if (size >= 4) {
crc_out = _mm_shuffle_epi8
(crc_out,
load128(reinterpret_cast<const char*>(shift128) + size));
goto done_128;
} else {
// only_less_than_4
/* Shift, zero-filling 5 to 7 of the 8-byte crc_out */
crc_out = _mm_shuffle_epi8(crc_out,
load128(shift_1_to_3_reflect + size - 1));
goto barrett;
}
} else {
crc_out = xor128(load128(buf), _mm512_castsi512_si128(crc_in));
goto done_128;
}
} else
return crc;
}
}
#ifdef __GNUC__
__attribute__((target("xsave")))
#endif
static bool os_have_avx512()
{
// The following flags must be set: SSE, AVX, OPMASK, ZMM_HI256, HI16_ZMM
return !(~_xgetbv(0 /*_XCR_XFEATURE_ENABLED_MASK*/) & 0xe6);
}
static ATTRIBUTE_NOINLINE bool have_vpclmulqdq(uint32_t cpuid_ecx)
{
if (!(cpuid_ecx & cpuid_ecx_XSAVE) || !os_have_avx512())
return false;
# ifdef _MSC_VER
int regs[4];
__cpuidex(regs, 7, 0);
uint32_t ebx = regs[1], ecx = regs[2];
# else
uint32_t eax = 0, ebx = 0, ecx = 0, edx = 0;
__cpuid_count(7, 0, eax, ebx, ecx, edx);
# endif
return ecx & 1U<<10/*VPCLMULQDQ*/ &&
!(~ebx & ((1U<<16/*AVX512F*/ | 1U<<17/*AVX512DQ*/ |
1U<<30/*AVX512BW*/ | 1U<<31/*AVX512VL*/)));
}
static unsigned crc32_vpclmulqdq(unsigned crc, const void *buf, size_t size)
{
return crc32_avx512(crc, static_cast<const char*>(buf), size, refl32);
}
static unsigned crc32c_vpclmulqdq(unsigned crc, const void *buf, size_t size)
{
return crc32_avx512(crc, static_cast<const char*>(buf), size, refl32c);
}
#endif
extern "C" my_crc32_t crc32_pclmul_enabled(void)
{
const uint32_t ecx= cpuid_ecx();
if (~ecx & cpuid_ecx_SSE42_AND_PCLMUL)
return nullptr;
#ifdef USE_VPCLMULQDQ
if (have_vpclmulqdq(ecx))
return crc32_vpclmulqdq;
#endif
return crc32_pclmul;
}
extern "C" my_crc32_t crc32c_x86_available(void)
{
const uint32_t ecx= cpuid_ecx();
#ifdef USE_VPCLMULQDQ
if (have_vpclmulqdq(ecx))
return crc32c_vpclmulqdq;
#endif
#if SIZEOF_SIZE_T == 8
switch (ecx & cpuid_ecx_SSE42_AND_PCLMUL) {
case cpuid_ecx_SSE42_AND_PCLMUL:
return crc32c_3way;
case cpuid_ecx_SSE42:
return crc32c_sse42;
}
#else
if (ecx & cpuid_ecx_SSE42)
return crc32c_sse42;
#endif
return nullptr;
}
extern "C" const char *crc32c_x86_impl(my_crc32_t c)
{
#ifdef USE_VPCLMULQDQ
if (c == crc32c_vpclmulqdq)
return "Using AVX512 instructions";
#endif
#if SIZEOF_SIZE_T == 8
if (c == crc32c_3way)
return "Using crc32 + pclmulqdq instructions";
#endif
if (c == crc32c_sse42)
return "Using SSE4.2 crc32 instructions";
return nullptr;
}