-
Notifications
You must be signed in to change notification settings - Fork 466
Crude port of Tofino dynamic hash to C++ #5043
New issue
Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.
By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.
Already on GitHub? Sign in to your account
Merged
Merged
Changes from all commits
Commits
File filter
Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
There are no files selected for viewing
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
278 changes: 278 additions & 0 deletions
278
backends/tofino/bf-utils/src/dynamic_hash/bfn_hash_algorithm.cpp
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,278 @@ | ||
| #include "backends/tofino/bf-utils/include/dynamic_hash/bfn_hash_algorithm.h" | ||
|
|
||
| #include <errno.h> | ||
| #include <limits.h> | ||
| #include <stdio.h> | ||
| #include <stdlib.h> | ||
| #include <string.h> | ||
|
|
||
| /** | ||
| * These values are based on the crc calculations provided at this url: | ||
| * http://reveng.sourceforge.net/crc-catalogue/all.htm | ||
| * | ||
| * It is understood that the top bit of the the polynomial is known to be == 1, | ||
| * but any polynomial over 64 bits would not fit. Thus the strings do not have | ||
| * this value | ||
| */ | ||
| static crc_alg_info_t standard_crc_algs[CRC_INVALID] = { | ||
| {"crc_8", 0x07, false, 0, 0}, | ||
| {"crc_8_darc", 0x39, true, 0, 0}, | ||
| {"crc_8_i_code", 0x1d, false, 0xfd, 0}, | ||
| {"crc_8_itu", 0x07, false, 0x55, 0x55}, | ||
| {"crc_8_maxim", 0x31, true, 0, 0}, | ||
| {"crc_8_rohc", 0x07, true, 0xff, 0}, | ||
| {"crc_8_wcdma", 0x9b, true, 0, 0}, | ||
| {"crc_16", 0x8005, true, 0, 0}, | ||
| {"crc_16_bypass", 0x8005, false, 0, 0}, | ||
| {"crc_16_dds_110", 0x8005, false, 0x800d, 0}, | ||
| // This one doesn't appear on the website, but kept to not break | ||
| // regressions | ||
| {"crc_16_dect", 0x0589, false, 1, 1}, | ||
| {"crc_16_dect_r", 0x0589, false, 0, 1}, | ||
| {"crc_16_dect_x", 0x0589, false, 0, 0}, | ||
| {"crc_16_dnp", 0x3d65, true, 0, 0xffff}, | ||
| {"crc_16_en_13757", 0x3d65, false, 0, 0xffff}, | ||
| {"crc_16_genibus", 0x1021, false, 0xffff, 0xffff}, | ||
| {"crc_16_maxim", 0x8005, true, 0, 0xffff}, | ||
| {"crc_16_mcrf4xx", 0x1021, true, 0xffff, 0}, | ||
| {"crc_16_riello", 0x1021, true, 0xb2aa, 0}, | ||
| {"crc_16_t10_dif", 0x8bb7, false, 0, 0}, | ||
| {"crc_16_teledisk", 0xa097, false, 0, 0}, | ||
| {"crc_16_usb", 0x8005, true, 0xffff, 0xffff}, | ||
| {"x_25", 0x1021, true, 0xffff, 0xffff}, | ||
| {"xmodem", 0x1021, false, 0, 0}, | ||
| {"modbus", 0x8005, true, 0xffff, 0}, | ||
| {"kermit", 0x1021, true, 0, 0}, | ||
| {"crc_ccitt_false", 0x1021, false, 0xffff, 0}, | ||
| {"crc_aug_ccitt", 0x1021, false, 0x1d0f, 0}, | ||
| {"crc_32", 0x04c11db7, true, 0xffffffff, 0xffffffff}, | ||
| {"crc_32_bzip2", 0x04c11db7, false, 0xffffffff, 0xffffffff}, | ||
| {"crc_32c", 0x1edc6f41, true, 0xffffffff, 0xffffffff}, | ||
| {"crc_32d", 0xa833982b, true, 0xffffffff, 0xffffffff}, | ||
| {"crc_32_mpeg", 0x04c11db7, false, 0xffffffff, 0}, | ||
| {"posix", 0x04c11db7, false, 0, 0xffffffff}, | ||
| {"crc_32q", 0x814141ab, false, 0, 0}, | ||
| {"jamcrc", 0x04c11db7, true, 0xffffffff, 0}, | ||
| {"xfer", 0x000000af, false, 0, 0}, | ||
| {"crc_64", 0x42f0e1eba9ea3693, false, 0, 0}, | ||
| {"crc_64_go_iso", 0x000000000000001b, true, 0xffffffffffffffff, 0xffffffffffffffff}, | ||
| {"crc_64_we", 0x42f0e1eba9ea3693, false, 0xffffffffffffffff, 0xffffffffffffffff}, | ||
| // This one doesn't appear on the website, but kept to not break | ||
| // regressions | ||
| {"crc_64_jones", 0xad93d23594c935a9, true, 0xffffffffffffffff, 0}}; | ||
|
|
||
| int determine_msb(uint64_t value) { | ||
| int rv = -1; | ||
| #if defined(__GNUC__) || defined(__clang__) | ||
| if (value) rv = 63 - __builtin_clzl(value); | ||
| #else | ||
| for (int i = 63; i >= 0; i--) { | ||
| if (((1ULL << i) & value) != 0ULL) return i; | ||
| } | ||
| #endif | ||
| return rv; | ||
| } | ||
|
|
||
| #define BUILD_CRC_ERRORS | ||
|
|
||
| static const char *bfn_crc_errors[BUILD_CRC_ERRORS] = { | ||
| "Polynomial is not odd", | ||
| "Init value is larger than the polynomial", | ||
| "Final xor value is larger than the polynomial", | ||
| }; | ||
|
|
||
| bool verify_algorithm(bfn_hash_algorithm_t *alg, const char **error_message) { | ||
| if ((alg->poly & 1) == 0) { | ||
| if (error_message) *error_message = bfn_crc_errors[0]; | ||
| return false; | ||
| } | ||
| if (alg->init && determine_msb(alg->init) + 1 > alg->hash_bit_width) { | ||
| if (error_message) *error_message = bfn_crc_errors[1]; | ||
| return false; | ||
| } | ||
| if (alg->final_xor && determine_msb(alg->final_xor) + 1 > alg->hash_bit_width) { | ||
| if (error_message) *error_message = bfn_crc_errors[2]; | ||
| return false; | ||
| } | ||
| return true; | ||
| } | ||
|
|
||
| /** | ||
| * Builds the algorithm from the standard crc algorithm position | ||
| */ | ||
| void build_standard_crc_algorithm(bfn_hash_algorithm_t *alg, bfn_crc_alg_t crc_alg) { | ||
| if (crc_alg >= CRC_8 && crc_alg <= CRC_8_WCDMA) | ||
| alg->hash_bit_width = 8; | ||
| else if (crc_alg >= CRC_16 && crc_alg <= CRC_AUG_CCITT) | ||
| alg->hash_bit_width = 16; | ||
| else if (crc_alg >= CRC_32 && crc_alg <= XFER) | ||
| alg->hash_bit_width = 32; | ||
| else if (crc_alg >= CRC_64 && crc_alg <= CRC_64_JONES) | ||
| alg->hash_bit_width = 64; | ||
|
|
||
| crc_alg_info_t crc_alg_info = standard_crc_algs[(int)crc_alg]; | ||
| alg->poly = crc_alg_info.poly; | ||
| alg->reverse = crc_alg_info.reverse; | ||
| alg->init = crc_alg_info.init; | ||
| alg->final_xor = crc_alg_info.final_xor; | ||
| alg->crc_type = crc_alg_str_to_type(crc_alg_info.crc_name); | ||
| } | ||
|
|
||
| void initialize_algorithm(bfn_hash_algorithm_t *alg, bfn_hash_alg_type_t hash_alg, bool msb, | ||
| bool extend, bfn_crc_alg_t crc_alg) { | ||
| alg->hash_alg = hash_alg; | ||
| alg->msb = msb; | ||
| alg->extend = extend; | ||
| if (crc_alg != CRC_INVALID) build_standard_crc_algorithm(alg, crc_alg); | ||
| } | ||
|
|
||
| static uint64_t invert_poly(uint64_t poly, int bit_width) { | ||
| uint64_t ret = 0, i = 0; | ||
| while (poly > 0) { | ||
| ret |= ((poly & 0x1) << (bit_width - i - 1)); | ||
| i++; | ||
| poly >>= 1; | ||
| } | ||
| return ret; | ||
| } | ||
|
|
||
| static void construct_stream(bfn_hash_algorithm_t *alg, uint64_t val, uint8_t *stream) { | ||
| uint8_t width = (alg->hash_bit_width + 7) / 8; | ||
| for (uint8_t i = 0; i < width; i++) { | ||
| stream[width - i - 1] = (val >> (i * 8)); | ||
| } | ||
| return; | ||
| } | ||
|
|
||
| static void shift_right(uint8_t *stream, uint8_t bit_width) { | ||
| uint8_t width = (bit_width + 7) / 8; | ||
| for (int i = width - 1; i >= 0; i--) { | ||
| stream[i] >>= 1; | ||
| if (i > 0) { | ||
| stream[i] |= (stream[i - 1] & 0x1) << 7; | ||
| } | ||
| } | ||
| } | ||
|
|
||
| static void shift_left(uint8_t *stream, uint8_t bit_width) { | ||
| uint8_t width = (bit_width + 7) / 8; | ||
| for (uint8_t i = 0; i < width; i++) { | ||
| stream[i] <<= 1; | ||
| if (i < width - 1) { | ||
| stream[i] |= (stream[i + 1] >> 7) & 0x1; | ||
| } | ||
| } | ||
| } | ||
|
|
||
| void initialize_crc_matrix(bfn_hash_algorithm_t *alg) { | ||
| if (alg->hash_alg != CRC_DYN) { | ||
| return; | ||
| } | ||
|
|
||
| uint32_t width = (alg->hash_bit_width + 7) / 8, i = 0; | ||
| std::vector<uint8_t> poly(width, 0), rem(width, 0); | ||
|
|
||
| uint64_t poly_val = alg->poly; | ||
| if (alg->reverse) { | ||
| poly_val = invert_poly(poly_val, alg->hash_bit_width); | ||
| } | ||
| construct_stream(alg, poly_val, poly.data()); | ||
| uint32_t byte = 0, bit = 0; | ||
| bool need_xor = false; | ||
| if (alg->reverse) { | ||
| for (byte = 0; byte < 256; byte++) { | ||
| F438 | memset(rem.data(), 0, width * sizeof(uint8_t)); | |
| rem[width - 1] = byte; | ||
| for (bit = 0; bit < 8; bit++) { | ||
| need_xor = rem[width - 1] & 0x1; | ||
| shift_right(rem.data(), alg->hash_bit_width); | ||
| if (need_xor) { | ||
| for (i = 0; i < width; i++) { | ||
| rem[i] ^= poly[i]; | ||
| } | ||
| } | ||
| } | ||
| memcpy(alg->crc_matrix[byte], rem.data(), width); | ||
| } | ||
| } else { | ||
| uint8_t offset = alg->hash_bit_width % 8; | ||
| uint8_t top_bit = offset == 0 ? 0x80 : 1 << ((offset - 1) % 8); | ||
| uint8_t top_mask = top_bit == 0x80 ? 0xff : (top_bit << 1) - 1; | ||
| for (byte = 0; byte < 256; byte++) { | ||
| memset(rem.data(), 0, width * sizeof(uint8_t)); | ||
| if (offset == 0) { | ||
| rem[0] = byte; | ||
| } else { | ||
| rem[0] = byte >> (8 - offset); | ||
| rem[1] = byte << offset; | ||
| } | ||
| for (bit = 0; bit < 8; bit++) { | ||
| need_xor = rem[0] & top_bit; | ||
| shift_left(rem.data(), alg->hash_bit_width); | ||
| if (need_xor) { | ||
| for (i = 0; i < width; i++) { | ||
| rem[i] ^= poly[i]; | ||
| } | ||
| } | ||
| rem[0] &= top_mask; | ||
| } | ||
| memcpy(alg->crc_matrix[byte], rem.data(), width); | ||
| } | ||
| } | ||
|
|
||
| return; | ||
| } | ||
|
|
||
| static uint8_t get_byte(uint8_t *stream, uint8_t index, uint8_t offset) { | ||
| if (offset == 0) { | ||
| return stream[index]; | ||
| } | ||
| return ((stream[index] << (8 - offset)) | (stream[index + 1] >> offset)); | ||
| } | ||
|
|
||
| void calculate_crc(bfn_hash_algorithm_t *alg, uint32_t hash_output_bits, uint8_t *stream, | ||
| uint32_t stream_len, uint8_t *crc) { | ||
| uint32_t i = 0; | ||
| uint8_t idx = 0; | ||
| uint8_t width = (alg->hash_bit_width + 7) / 8; | ||
| uint8_t hash_output_bytes = (hash_output_bits + 7) / 8; | ||
| std::vector<uint8_t> final_xor(width, 0); | ||
| memset(crc, 0, hash_output_bytes * sizeof(uint8_t)); | ||
| construct_stream(alg, alg->init, crc); | ||
| construct_stream(alg, alg->final_xor, final_xor.data()); | ||
| uint8_t *crc_str = crc + hash_output_bytes - width; | ||
|
|
||
| for (i = 0; i < stream_len; i++) { | ||
| if (alg->reverse) { | ||
| idx = crc_str[width - 1] ^ stream[i]; | ||
| for (int j = width - 1; j > 0; j--) { | ||
| crc_str[j] = crc_str[j - 1] ^ alg->crc_matrix[idx][j]; | ||
| } | ||
| crc_str[0] = alg->crc_matrix[idx][0]; | ||
| } else { | ||
| uint8_t offset = alg->hash_bit_width % 8; | ||
| uint8_t mask = offset == 0 ? 0xff : (1 << offset) - 1; | ||
| idx = get_byte(crc_str, 0, offset) ^ stream[i]; | ||
| for (uint8_t j = 0; j < width - 1; j++) { | ||
| crc_str[j] = (crc_str[j + 1] ^ alg->crc_matrix[idx][j]) & mask; | ||
| mask = 0xff; | ||
| } | ||
| crc_str[width - 1] = alg->crc_matrix[idx][width - 1]; | ||
| } | ||
| } | ||
|
|
||
| for (i = 0; i < width; i++) { | ||
| crc_str[i] ^= final_xor[i]; | ||
| } | ||
|
|
||
| if (alg->extend) { | ||
| for (i = 0; i < (uint32_t)(hash_output_bytes - width); i++) { | ||
| *(crc_str - i - 1) = crc_str[width - i % width - 1]; | ||
| } | ||
| if (hash_output_bits % 8) { | ||
| crc[0] &= (1 << (hash_output_bits % 8)) - 1; | ||
| } | ||
| } | ||
|
|
||
| return; | ||
| } |
Oops, something went wrong.
Oops, something went wrong.
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
Assume this is remove because of the frontend dependency?
Uh oh!
There was an error while loading. Please reload this page.
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
Yes. Actually, the majority
add_dependenciesare not needed at all. This seems to be an old hack used to "close" some absence of proper dependencies. This needs to be eventually removed from everywhere and replaced with proper deps (e.g.target_link_libraries, etc.)