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@@ -21,6 +21,7 @@
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* All rights reserved. Use of this source code is governed by a
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* All rights reserved. Use of this source code is governed by a
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* BSD-style license that can be found in the LICENSE file.
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* BSD-style license that can be found in the LICENSE file.
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*/
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*/
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+#include <assert.h>
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#include <arpa/inet.h>
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#include <arpa/inet.h>
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#include <stdint.h>
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#include <stdint.h>
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#include <unistd.h>
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#include <unistd.h>
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@@ -30,47 +31,124 @@
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#include "bulk_crc32.h"
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#include "bulk_crc32.h"
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#include "gcc_optimizations.h"
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#include "gcc_optimizations.h"
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+#define USE_PIPELINED
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+
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typedef uint32_t (*crc_update_func_t)(uint32_t, const uint8_t *, size_t);
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typedef uint32_t (*crc_update_func_t)(uint32_t, const uint8_t *, size_t);
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static uint32_t crc_init();
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static uint32_t crc_init();
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static uint32_t crc_val(uint32_t crc);
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static uint32_t crc_val(uint32_t crc);
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static uint32_t crc32_zlib_sb8(uint32_t crc, const uint8_t *buf, size_t length);
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static uint32_t crc32_zlib_sb8(uint32_t crc, const uint8_t *buf, size_t length);
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static uint32_t crc32c_sb8(uint32_t crc, const uint8_t *buf, size_t length);
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static uint32_t crc32c_sb8(uint32_t crc, const uint8_t *buf, size_t length);
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+#ifdef USE_PIPELINED
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+static void pipelined_crc32c(uint32_t *crc1, uint32_t *crc2, uint32_t *crc3, const uint8_t *p_buf, size_t block_size, int num_blocks);
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+#endif USE_PIPELINED
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+static int cached_cpu_supports_crc32; // initialized by constructor below
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+static uint32_t crc32c_hardware(uint32_t crc, const uint8_t* data, size_t length);
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+
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int bulk_verify_crc(const uint8_t *data, size_t data_len,
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int bulk_verify_crc(const uint8_t *data, size_t data_len,
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const uint32_t *sums, int checksum_type,
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const uint32_t *sums, int checksum_type,
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int bytes_per_checksum,
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int bytes_per_checksum,
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crc32_error_t *error_info) {
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crc32_error_t *error_info) {
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+#ifdef USE_PIPELINED
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+ uint32_t crc1, crc2, crc3;
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+ int n_blocks = data_len / bytes_per_checksum;
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+ int remainder = data_len % bytes_per_checksum;
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+ int do_pipelined = 0;
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+#endif
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+ uint32_t crc;
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crc_update_func_t crc_update_func;
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crc_update_func_t crc_update_func;
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switch (checksum_type) {
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switch (checksum_type) {
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case CRC32_ZLIB_POLYNOMIAL:
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case CRC32_ZLIB_POLYNOMIAL:
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crc_update_func = crc32_zlib_sb8;
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crc_update_func = crc32_zlib_sb8;
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break;
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break;
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case CRC32C_POLYNOMIAL:
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case CRC32C_POLYNOMIAL:
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- crc_update_func = crc32c_sb8;
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+ if (likely(cached_cpu_supports_crc32)) {
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+ crc_update_func = crc32c_hardware;
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+#ifdef USE_PIPELINED
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+ do_pipelined = 1;
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+#endif
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+ } else {
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+ crc_update_func = crc32c_sb8;
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+ }
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break;
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break;
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default:
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default:
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return INVALID_CHECKSUM_TYPE;
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return INVALID_CHECKSUM_TYPE;
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}
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}
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+#ifdef USE_PIPELINED
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+ if (do_pipelined) {
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+ /* Process three blocks at a time */
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+ while (likely(n_blocks >= 3)) {
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+ crc1 = crc2 = crc3 = crc_init();
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+ pipelined_crc32c(&crc1, &crc2, &crc3, data, bytes_per_checksum, 3);
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+
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+ crc = ntohl(crc_val(crc1));
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+ if ((crc = ntohl(crc_val(crc1))) != *sums)
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+ goto return_crc_error;
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+ sums++;
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+ data += bytes_per_checksum;
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+ if ((crc = ntohl(crc_val(crc2))) != *sums)
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+ goto return_crc_error;
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+ sums++;
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+ data += bytes_per_checksum;
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+ if ((crc = ntohl(crc_val(crc3))) != *sums)
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+ goto return_crc_error;
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+ sums++;
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+ data += bytes_per_checksum;
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+ n_blocks -= 3;
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+ }
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+
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+ /* One or two blocks */
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+ if (n_blocks) {
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+ crc1 = crc2 = crc_init();
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+ pipelined_crc32c(&crc1, &crc2, &crc3, data, bytes_per_checksum, n_blocks);
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+
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+ if ((crc = ntohl(crc_val(crc1))) != *sums)
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+ goto return_crc_error;
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+ data += bytes_per_checksum;
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+ sums++;
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+ if (n_blocks == 2) {
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+ if ((crc = ntohl(crc_val(crc2))) != *sums)
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+ goto return_crc_error;
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+ sums++;
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+ data += bytes_per_checksum;
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+ }
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+ }
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+
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+ /* For something smaller than a block */
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+ if (remainder) {
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+ crc1 = crc_init();
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+ pipelined_crc32c(&crc1, &crc2, &crc3, data, remainder, 1);
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+
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+ if ((crc = ntohl(crc_val(crc1))) != *sums)
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+ goto return_crc_error;
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+ }
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+ return CHECKSUMS_VALID;
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+ }
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+#endif
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+
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while (likely(data_len > 0)) {
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while (likely(data_len > 0)) {
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int len = likely(data_len >= bytes_per_checksum) ? bytes_per_checksum : data_len;
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int len = likely(data_len >= bytes_per_checksum) ? bytes_per_checksum : data_len;
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- uint32_t crc = crc_init();
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+ crc = crc_init();
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crc = crc_update_func(crc, data, len);
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crc = crc_update_func(crc, data, len);
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crc = ntohl(crc_val(crc));
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crc = ntohl(crc_val(crc));
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if (unlikely(crc != *sums)) {
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if (unlikely(crc != *sums)) {
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- if (error_info != NULL) {
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- error_info->got_crc = crc;
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- error_info->expected_crc = *sums;
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- error_info->bad_data = data;
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- }
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- return INVALID_CHECKSUM_DETECTED;
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+ goto return_crc_error;
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}
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}
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data += len;
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data += len;
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data_len -= len;
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data_len -= len;
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sums++;
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sums++;
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}
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}
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return CHECKSUMS_VALID;
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return CHECKSUMS_VALID;
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+
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+return_crc_error:
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+ if (error_info != NULL) {
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+ error_info->got_crc = crc;
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+ error_info->expected_crc = *sums;
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+ error_info->bad_data = data;
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+ }
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+ return INVALID_CHECKSUM_DETECTED;
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}
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}
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@@ -154,3 +232,417 @@ static uint32_t crc32_zlib_sb8(
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}
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}
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return crc;
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return crc;
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}
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}
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+
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+///////////////////////////////////////////////////////////////////////////
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+// Begin code for SSE4.2 specific hardware support of CRC32C
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+///////////////////////////////////////////////////////////////////////////
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+
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+#if (defined(__amd64__) || defined(__i386)) && defined(__GNUC__)
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+# define SSE42_FEATURE_BIT (1 << 20)
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+# define CPUID_FEATURES 1
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+/**
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+ * Call the cpuid instruction to determine CPU feature flags.
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+ */
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+static uint32_t cpuid(uint32_t eax_in) {
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+ uint32_t eax, ebx, ecx, edx;
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+# if defined(__PIC__) && !defined(__LP64__)
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+// 32-bit PIC code uses the ebx register for the base offset --
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+// have to save and restore it on the stack
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+ asm("pushl %%ebx\n\t"
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+ "cpuid\n\t"
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+ "movl %%ebx, %[ebx]\n\t"
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+ "popl %%ebx" : "=a" (eax), [ebx] "=r"(ebx), "=c"(ecx), "=d"(edx) : "a" (eax_in)
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+ : "cc");
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+# else
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+ asm("cpuid" : "=a" (eax), "=b"(ebx), "=c"(ecx), "=d"(edx) : "a"(eax_in)
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+ : "cc");
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+# endif
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+
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+ return ecx;
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+}
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+
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+/**
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+ * On library load, initiailize the cached value above for
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+ * whether the cpu supports SSE4.2's crc32 instruction.
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+ */
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+void __attribute__ ((constructor)) init_cpu_support_flag(void) {
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+ uint32_t ecx = cpuid(CPUID_FEATURES);
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+ cached_cpu_supports_crc32 = ecx & SSE42_FEATURE_BIT;
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+}
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+
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+
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+//
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+// Definitions of the SSE4.2 crc32 operations. Using these instead of
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+// the GCC __builtin_* intrinsics allows this code to compile without
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+// -msse4.2, since we do dynamic CPU detection at runtime.
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+//
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+
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+# ifdef __LP64__
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+inline uint64_t _mm_crc32_u64(uint64_t crc, uint64_t value) {
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+ asm("crc32q %[value], %[crc]\n" : [crc] "+r" (crc) : [value] "rm" (value));
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+ return crc;
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+}
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+# endif
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+
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+inline uint32_t _mm_crc32_u32(uint32_t crc, uint32_t value) {
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+ asm("crc32l %[value], %[crc]\n" : [crc] "+r" (crc) : [value] "rm" (value));
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+ return crc;
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+}
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+
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+inline uint32_t _mm_crc32_u16(uint32_t crc, uint16_t value) {
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+ asm("crc32w %[value], %[crc]\n" : [crc] "+r" (crc) : [value] "rm" (value));
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+ return crc;
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+}
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+
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+inline uint32_t _mm_crc32_u8(uint32_t crc, uint8_t value) {
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+ asm("crc32b %[value], %[crc]\n" : [crc] "+r" (crc) : [value] "rm" (value));
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+ return crc;
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+}
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+
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+
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+# ifdef __LP64__
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+/**
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+ * Hardware-accelerated CRC32C calculation using the 64-bit instructions.
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+ */
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+static uint32_t crc32c_hardware(uint32_t crc, const uint8_t* p_buf, size_t length) {
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+ // start directly at p_buf, even if it's an unaligned address. According
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+ // to the original author of this code, doing a small run of single bytes
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+ // to word-align the 64-bit instructions doesn't seem to help, but
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+ // we haven't reconfirmed those benchmarks ourselves.
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+ uint64_t crc64bit = crc;
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+ size_t i;
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+ for (i = 0; i < length / sizeof(uint64_t); i++) {
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+ crc64bit = _mm_crc32_u64(crc64bit, *(uint64_t*) p_buf);
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+ p_buf += sizeof(uint64_t);
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+ }
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+
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+ // This ugly switch is slightly faster for short strings than the straightforward loop
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+ uint32_t crc32bit = (uint32_t) crc64bit;
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+ length &= sizeof(uint64_t) - 1;
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+ switch (length) {
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+ case 7:
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+ crc32bit = _mm_crc32_u8(crc32bit, *p_buf++);
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+ case 6:
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+ crc32bit = _mm_crc32_u16(crc32bit, *(uint16_t*) p_buf);
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+ p_buf += 2;
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+ // case 5 is below: 4 + 1
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+ case 4:
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+ crc32bit = _mm_crc32_u32(crc32bit, *(uint32_t*) p_buf);
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+ break;
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+ case 3:
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+ crc32bit = _mm_crc32_u8(crc32bit, *p_buf++);
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+ case 2:
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+ crc32bit = _mm_crc32_u16(crc32bit, *(uint16_t*) p_buf);
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+ break;
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+ case 5:
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+ crc32bit = _mm_crc32_u32(crc32bit, *(uint32_t*) p_buf);
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+ p_buf += 4;
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+ case 1:
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+ crc32bit = _mm_crc32_u8(crc32bit, *p_buf);
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+ break;
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+ case 0:
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+ break;
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+ default:
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+ // This should never happen; enable in debug code
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+ assert(0 && "ended up with 8 or more bytes at tail of calculation");
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+ }
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+
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+ return crc32bit;
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+}
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+
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+#ifdef USE_PIPELINED
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+/**
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+ * Pipelined version of hardware-accelerated CRC32C calculation using
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+ * the 64 bit crc32q instruction.
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+ * One crc32c instruction takes three cycles, but two more with no data
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+ * dependency can be in the pipeline to achieve something close to single
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+ * instruction/cycle. Here we feed three blocks in RR.
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+ *
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+ * crc1, crc2, crc3 : Store initial checksum for each block before
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+ * calling. When it returns, updated checksums are stored.
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+ * p_buf : The base address of the data buffer. The buffer should be
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+ * at least as big as block_size * num_blocks.
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+ * block_size : The size of each block in bytes.
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+ * num_blocks : The number of blocks to work on. Min = 1, Max = 3
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+ */
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+static void pipelined_crc32c(uint32_t *crc1, uint32_t *crc2, uint32_t *crc3, const uint8_t *p_buf, size_t block_size, int num_blocks) {
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+ uint64_t c1 = *crc1;
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+ uint64_t c2 = *crc2;
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+ uint64_t c3 = *crc3;
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+ uint64_t *data = (uint64_t*)p_buf;
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+ int counter = block_size / sizeof(uint64_t);
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+ int remainder = block_size % sizeof(uint64_t);
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+ uint8_t *bdata;
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+
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+ /* We do switch here because the loop has to be tight in order
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+ * to fill the pipeline. Any other statement inside the loop
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+ * or inbetween crc32 instruction can slow things down. Calling
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+ * individual crc32 instructions three times from C also causes
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+ * gcc to insert other instructions inbetween.
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+ *
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+ * Do not rearrange the following code unless you have verified
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+ * the generated machine code is as efficient as before.
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+ */
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+ switch (num_blocks) {
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+ case 3:
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+ /* Do three blocks */
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+ while (likely(counter)) {
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+ __asm__ __volatile__(
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+ "crc32q (%7), %0;\n\t"
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|
|
+ "crc32q (%7,%6,1), %1;\n\t"
|
|
|
|
+ "crc32q (%7,%6,2), %2;\n\t"
|
|
|
|
+ : "=r"(c1), "=r"(c2), "=r"(c3)
|
|
|
|
+ : "r"(c1), "r"(c2), "r"(c3), "r"(block_size), "r"(data)
|
|
|
|
+ );
|
|
|
|
+ data++;
|
|
|
|
+ counter--;
|
|
|
|
+ }
|
|
|
|
+
|
|
|
|
+ /* Take care of the remainder. They are only up to three bytes,
|
|
|
|
+ * so performing byte-level crc32 won't take much time.
|
|
|
|
+ */
|
|
|
|
+ bdata = (uint8_t*)data;
|
|
|
|
+ while (likely(remainder)) {
|
|
|
|
+ __asm__ __volatile__(
|
|
|
|
+ "crc32b (%7), %0;\n\t"
|
|
|
|
+ "crc32b (%7,%6,1), %1;\n\t"
|
|
|
|
+ "crc32b (%7,%6,2), %2;\n\t"
|
|
|
|
+ : "=r"(c1), "=r"(c2), "=r"(c3)
|
|
|
|
+ : "r"(c1), "r"(c2), "r"(c3), "r"(block_size), "r"(bdata)
|
|
|
|
+ );
|
|
|
|
+ bdata++;
|
|
|
|
+ remainder--;
|
|
|
|
+ }
|
|
|
|
+ break;
|
|
|
|
+ case 2:
|
|
|
|
+ /* Do two blocks */
|
|
|
|
+ while (likely(counter)) {
|
|
|
|
+ __asm__ __volatile__(
|
|
|
|
+ "crc32q (%5), %0;\n\t"
|
|
|
|
+ "crc32q (%5,%4,1), %1;\n\t"
|
|
|
|
+ : "=r"(c1), "=r"(c2)
|
|
|
|
+ : "r"(c1), "r"(c2), "r"(block_size), "r"(data)
|
|
|
|
+ );
|
|
|
|
+ data++;
|
|
|
|
+ counter--;
|
|
|
|
+ }
|
|
|
|
+
|
|
|
|
+ bdata = (uint8_t*)data;
|
|
|
|
+ while (likely(remainder)) {
|
|
|
|
+ __asm__ __volatile__(
|
|
|
|
+ "crc32b (%5), %0;\n\t"
|
|
|
|
+ "crc32b (%5,%4,1), %1;\n\t"
|
|
|
|
+ : "=r"(c1), "=r"(c2)
|
|
|
|
+ : "r"(c1), "r"(c2), "r"(c3), "r"(block_size), "r"(bdata)
|
|
|
|
+ );
|
|
|
|
+ bdata++;
|
|
|
|
+ remainder--;
|
|
|
|
+ }
|
|
|
|
+ break;
|
|
|
|
+ case 1:
|
|
|
|
+ /* single block */
|
|
|
|
+ while (likely(counter)) {
|
|
|
|
+ __asm__ __volatile__(
|
|
|
|
+ "crc32q (%2), %0;\n\t"
|
|
|
|
+ : "=r"(c1)
|
|
|
|
+ : "r"(c1), "r"(data)
|
|
|
|
+ );
|
|
|
|
+ data++;
|
|
|
|
+ counter--;
|
|
|
|
+ }
|
|
|
|
+ bdata = (uint8_t*)data;
|
|
|
|
+ while (likely(remainder)) {
|
|
|
|
+ __asm__ __volatile__(
|
|
|
|
+ "crc32b (%2), %0;\n\t"
|
|
|
|
+ : "=r"(c1)
|
|
|
|
+ : "r"(c1), "r"(bdata)
|
|
|
|
+ );
|
|
|
|
+ bdata++;
|
|
|
|
+ remainder--;
|
|
|
|
+ }
|
|
|
|
+ break;
|
|
|
|
+ case 0:
|
|
|
|
+ return;
|
|
|
|
+ default:
|
|
|
|
+ assert(0 && "BUG: Invalid number of checksum blocks");
|
|
|
|
+ }
|
|
|
|
+
|
|
|
|
+ *crc1 = c1;
|
|
|
|
+ *crc2 = c2;
|
|
|
|
+ *crc3 = c3;
|
|
|
|
+ return;
|
|
|
|
+}
|
|
|
|
+#endif /* USE_PIPELINED */
|
|
|
|
+
|
|
|
|
+# else // 32-bit
|
|
|
|
+
|
|
|
|
+/**
|
|
|
|
+ * Hardware-accelerated CRC32C calculation using the 32-bit instructions.
|
|
|
|
+ */
|
|
|
|
+static uint32_t crc32c_hardware(uint32_t crc, const uint8_t* p_buf, size_t length) {
|
|
|
|
+ // start directly at p_buf, even if it's an unaligned address. According
|
|
|
|
+ // to the original author of this code, doing a small run of single bytes
|
|
|
|
+ // to word-align the 64-bit instructions doesn't seem to help, but
|
|
|
|
+ // we haven't reconfirmed those benchmarks ourselves.
|
|
|
|
+ size_t i;
|
|
|
|
+ for (i = 0; i < length / sizeof(uint32_t); i++) {
|
|
|
|
+ crc = _mm_crc32_u32(crc, *(uint32_t*) p_buf);
|
|
|
|
+ p_buf += sizeof(uint32_t);
|
|
|
|
+ }
|
|
|
|
+
|
|
|
|
+ // This ugly switch is slightly faster for short strings than the straightforward loop
|
|
|
|
+ length &= sizeof(uint32_t) - 1;
|
|
|
|
+ switch (length) {
|
|
|
|
+ case 3:
|
|
|
|
+ crc = _mm_crc32_u8(crc, *p_buf++);
|
|
|
|
+ case 2:
|
|
|
|
+ crc = _mm_crc32_u16(crc, *(uint16_t*) p_buf);
|
|
|
|
+ break;
|
|
|
|
+ case 1:
|
|
|
|
+ crc = _mm_crc32_u8(crc, *p_buf);
|
|
|
|
+ break;
|
|
|
|
+ case 0:
|
|
|
|
+ break;
|
|
|
|
+ default:
|
|
|
|
+ // This should never happen; enable in debug code
|
|
|
|
+ assert(0 && "ended up with 4 or more bytes at tail of calculation");
|
|
|
|
+ }
|
|
|
|
+
|
|
|
|
+ return crc;
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+#ifdef USE_PIPELINED
|
|
|
|
+/**
|
|
|
|
+ * Pipelined version of hardware-accelerated CRC32C calculation using
|
|
|
|
+ * the 32 bit crc32l instruction.
|
|
|
|
+ * One crc32c instruction takes three cycles, but two more with no data
|
|
|
|
+ * dependency can be in the pipeline to achieve something close to single
|
|
|
|
+ * instruction/cycle. Here we feed three blocks in RR.
|
|
|
|
+ *
|
|
|
|
+ * crc1, crc2, crc3 : Store initial checksum for each block before
|
|
|
|
+ * calling. When it returns, updated checksums are stored.
|
|
|
|
+ * data : The base address of the data buffer. The buffer should be
|
|
|
|
+ * at least as big as block_size * num_blocks.
|
|
|
|
+ * block_size : The size of each block in bytes.
|
|
|
|
+ * num_blocks : The number of blocks to work on. Min = 1, Max = 3
|
|
|
|
+ */
|
|
|
|
+static void pipelined_crc32c(uint32_t *crc1, uint32_t *crc2, uint32_t *crc3, const uint8_t *p_buf, size_t block_size, int num_blocks) {
|
|
|
|
+ uint32_t c1 = *crc1;
|
|
|
|
+ uint32_t c2 = *crc2;
|
|
|
|
+ uint32_t c3 = *crc3;
|
|
|
|
+ int counter = block_size / sizeof(uint32_t);
|
|
|
|
+ int remainder = block_size % sizeof(uint32_t);
|
|
|
|
+ uint32_t *data = (uint32_t*)p_buf;
|
|
|
|
+ uint8_t *bdata;
|
|
|
|
+
|
|
|
|
+ /* We do switch here because the loop has to be tight in order
|
|
|
|
+ * to fill the pipeline. Any other statement inside the loop
|
|
|
|
+ * or inbetween crc32 instruction can slow things down. Calling
|
|
|
|
+ * individual crc32 instructions three times from C also causes
|
|
|
|
+ * gcc to insert other instructions inbetween.
|
|
|
|
+ *
|
|
|
|
+ * Do not rearrange the following code unless you have verified
|
|
|
|
+ * the generated machine code is as efficient as before.
|
|
|
|
+ */
|
|
|
|
+ switch (num_blocks) {
|
|
|
|
+ case 3:
|
|
|
|
+ /* Do three blocks */
|
|
|
|
+ while (likely(counter)) {
|
|
|
|
+ __asm__ __volatile__(
|
|
|
|
+ "crc32l (%7), %0;\n\t"
|
|
|
|
+ "crc32l (%7,%6,1), %1;\n\t"
|
|
|
|
+ "crc32l (%7,%6,2), %2;\n\t"
|
|
|
|
+ : "=r"(c1), "=r"(c2), "=r"(c3)
|
|
|
|
+ : "r"(c1), "r"(c2), "r"(c3), "r"(block_size), "r"(data)
|
|
|
|
+ );
|
|
|
|
+ data++;
|
|
|
|
+ counter--;
|
|
|
|
+ }
|
|
|
|
+ /* Take care of the remainder. They are only up to three bytes,
|
|
|
|
+ * so performing byte-level crc32 won't take much time.
|
|
|
|
+ */
|
|
|
|
+ bdata = (uint8_t*)data;
|
|
|
|
+ while (likely(remainder)) {
|
|
|
|
+ __asm__ __volatile__(
|
|
|
|
+ "crc32b (%7), %0;\n\t"
|
|
|
|
+ "crc32b (%7,%6,1), %1;\n\t"
|
|
|
|
+ "crc32b (%7,%6,2), %2;\n\t"
|
|
|
|
+ : "=r"(c1), "=r"(c2), "=r"(c3)
|
|
|
|
+ : "r"(c1), "r"(c2), "r"(c3), "r"(block_size), "r"(bdata)
|
|
|
|
+ );
|
|
|
|
+ bdata++;
|
|
|
|
+ remainder--;
|
|
|
|
+ }
|
|
|
|
+ break;
|
|
|
|
+ case 2:
|
|
|
|
+ /* Do two blocks */
|
|
|
|
+ while (likely(counter)) {
|
|
|
|
+ __asm__ __volatile__(
|
|
|
|
+ "crc32l (%5), %0;\n\t"
|
|
|
|
+ "crc32l (%5,%4,1), %1;\n\t"
|
|
|
|
+ : "=r"(c1), "=r"(c2)
|
|
|
|
+ : "r"(c1), "r"(c2), "r"(block_size), "r"(data)
|
|
|
|
+ );
|
|
|
|
+ data++;
|
|
|
|
+ counter--;
|
|
|
|
+ }
|
|
|
|
+
|
|
|
|
+ bdata = (uint8_t*)data;
|
|
|
|
+ while (likely(remainder)) {
|
|
|
|
+ __asm__ __volatile__(
|
|
|
|
+ "crc32b (%5), %0;\n\t"
|
|
|
|
+ "crc32b (%5,%4,1), %1;\n\t"
|
|
|
|
+ : "=r"(c1), "=r"(c2)
|
|
|
|
+ : "r"(c1), "r"(c2), "r"(c3), "r"(block_size), "r"(bdata)
|
|
|
|
+ );
|
|
|
|
+ bdata++;
|
|
|
|
+ remainder--;
|
|
|
|
+ }
|
|
|
|
+ break;
|
|
|
|
+ case 1:
|
|
|
|
+ /* single block */
|
|
|
|
+ while (likely(counter)) {
|
|
|
|
+ __asm__ __volatile__(
|
|
|
|
+ "crc32l (%2), %0;\n\t"
|
|
|
|
+ : "=r"(c1)
|
|
|
|
+ : "r"(c1), "r"(data)
|
|
|
|
+ );
|
|
|
|
+ data++;
|
|
|
|
+ counter--;
|
|
|
|
+ }
|
|
|
|
+ bdata = (uint8_t*)data;
|
|
|
|
+ while (likely(remainder)) {
|
|
|
|
+ __asm__ __volatile__(
|
|
|
|
+ "crc32b (%2), %0;\n\t"
|
|
|
|
+ : "=r"(c1)
|
|
|
|
+ : "r"(c1), "r"(bdata)
|
|
|
|
+ );
|
|
|
|
+ bdata++;
|
|
|
|
+ remainder--;
|
|
|
|
+ }
|
|
|
|
+ break;
|
|
|
|
+ case 0:
|
|
|
|
+ return;
|
|
|
|
+ default:
|
|
|
|
+ assert(0 && "BUG: Invalid number of checksum blocks");
|
|
|
|
+ }
|
|
|
|
+
|
|
|
|
+ *crc1 = c1;
|
|
|
|
+ *crc2 = c2;
|
|
|
|
+ *crc3 = c3;
|
|
|
|
+ return;
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+#endif /* USE_PIPELINED */
|
|
|
|
+
|
|
|
|
+# endif // 64-bit vs 32-bit
|
|
|
|
+
|
|
|
|
+#else // end x86 architecture
|
|
|
|
+
|
|
|
|
+static uint32_t crc32c_hardware(uint32_t crc, const uint8_t* data, size_t length) {
|
|
|
|
+ // never called!
|
|
|
|
+ assert(0 && "hardware crc called on an unsupported platform");
|
|
|
|
+ return 0;
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+#endif
|