diff options
Diffstat (limited to 'lib/gen_crc32table.c')
| -rw-r--r-- | lib/gen_crc32table.c | 81 |
1 files changed, 61 insertions, 20 deletions
diff --git a/lib/gen_crc32table.c b/lib/gen_crc32table.c index 85d0e41..8f8d543 100644 --- a/lib/gen_crc32table.c +++ b/lib/gen_crc32table.c @@ -1,14 +1,29 @@ #include <stdio.h> +#include "../include/generated/autoconf.h" #include "crc32defs.h" #include <inttypes.h> #define ENTRIES_PER_LINE 4 -#define LE_TABLE_SIZE (1 << CRC_LE_BITS) -#define BE_TABLE_SIZE (1 << CRC_BE_BITS) +#if CRC_LE_BITS > 8 +# define LE_TABLE_ROWS (CRC_LE_BITS/8) +# define LE_TABLE_SIZE 256 +#else +# define LE_TABLE_ROWS 1 +# define LE_TABLE_SIZE (1 << CRC_LE_BITS) +#endif -static uint32_t crc32table_le[4][LE_TABLE_SIZE]; -static uint32_t crc32table_be[4][BE_TABLE_SIZE]; +#if CRC_BE_BITS > 8 +# define BE_TABLE_ROWS (CRC_BE_BITS/8) +# define BE_TABLE_SIZE 256 +#else +# define BE_TABLE_ROWS 1 +# define BE_TABLE_SIZE (1 << CRC_BE_BITS) +#endif + +static uint32_t crc32table_le[LE_TABLE_ROWS][256]; +static uint32_t crc32table_be[BE_TABLE_ROWS][256]; +static uint32_t crc32ctable_le[LE_TABLE_ROWS][256]; /** * crc32init_le() - allocate and initialize LE table data @@ -17,27 +32,38 @@ static uint32_t crc32table_be[4][BE_TABLE_SIZE]; * fact that crctable[i^j] = crctable[i] ^ crctable[j]. * */ -static void crc32init_le(void) +static void crc32init_le_generic(const uint32_t polynomial, + uint32_t (*tab)[256]) { unsigned i, j; uint32_t crc = 1; - crc32table_le[0][0] = 0; + tab[0][0] = 0; - for (i = 1 << (CRC_LE_BITS - 1); i; i >>= 1) { - crc = (crc >> 1) ^ ((crc & 1) ? CRCPOLY_LE : 0); + for (i = LE_TABLE_SIZE >> 1; i; i >>= 1) { + crc = (crc >> 1) ^ ((crc & 1) ? polynomial : 0); for (j = 0; j < LE_TABLE_SIZE; j += 2 * i) - crc32table_le[0][i + j] = crc ^ crc32table_le[0][j]; + tab[0][i + j] = crc ^ tab[0][j]; } for (i = 0; i < LE_TABLE_SIZE; i++) { - crc = crc32table_le[0][i]; - for (j = 1; j < 4; j++) { - crc = crc32table_le[0][crc & 0xff] ^ (crc >> 8); - crc32table_le[j][i] = crc; + crc = tab[0][i]; + for (j = 1; j < LE_TABLE_ROWS; j++) { + crc = tab[0][crc & 0xff] ^ (crc >> 8); + tab[j][i] = crc; } } } +static void crc32init_le(void) +{ + crc32init_le_generic(CRCPOLY_LE, crc32table_le); +} + +static void crc32cinit_le(void) +{ + crc32init_le_generic(CRC32C_POLY_LE, crc32ctable_le); +} + /** * crc32init_be() - allocate and initialize BE table data */ @@ -55,18 +81,18 @@ static void crc32init_be(void) } for (i = 0; i < BE_TABLE_SIZE; i++) { crc = crc32table_be[0][i]; - for (j = 1; j < 4; j++) { + for (j = 1; j < BE_TABLE_ROWS; j++) { crc = crc32table_be[0][(crc >> 24) & 0xff] ^ (crc << 8); crc32table_be[j][i] = crc; } } } -static void output_table(uint32_t table[4][256], int len, char *trans) +static void output_table(uint32_t (*table)[256], int rows, int len, char *trans) { int i, j; - for (j = 0 ; j < 4; j++) { + for (j = 0 ; j < rows; j++) { printf("{"); for (i = 0; i < len - 1; i++) { if (i % ENTRIES_PER_LINE == 0) @@ -83,15 +109,30 @@ int main(int argc, char** argv) if (CRC_LE_BITS > 1) { crc32init_le(); - printf("static const u32 crc32table_le[4][256] = {"); - output_table(crc32table_le, LE_TABLE_SIZE, "tole"); + printf("static const u32 __cacheline_aligned " + "crc32table_le[%d][%d] = {", + LE_TABLE_ROWS, LE_TABLE_SIZE); + output_table(crc32table_le, LE_TABLE_ROWS, + LE_TABLE_SIZE, "tole"); printf("};\n"); } if (CRC_BE_BITS > 1) { crc32init_be(); - printf("static const u32 crc32table_be[4][256] = {"); - output_table(crc32table_be, BE_TABLE_SIZE, "tobe"); + printf("static const u32 __cacheline_aligned " + "crc32table_be[%d][%d] = {", + BE_TABLE_ROWS, BE_TABLE_SIZE); + output_table(crc32table_be, LE_TABLE_ROWS, + BE_TABLE_SIZE, "tobe"); + printf("};\n"); + } + if (CRC_LE_BITS > 1) { + crc32cinit_le(); + printf("static const u32 __cacheline_aligned " + "crc32ctable_le[%d][%d] = {", + LE_TABLE_ROWS, LE_TABLE_SIZE); + output_table(crc32ctable_le, LE_TABLE_ROWS, + LE_TABLE_SIZE, "tole"); printf("};\n"); } |
