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Diffstat (limited to 'lib/gen_crc32table.c')
-rw-r--r--lib/gen_crc32table.c113
1 files changed, 30 insertions, 83 deletions
diff --git a/lib/gen_crc32table.c b/lib/gen_crc32table.c
index f755b997b967..6d03425b849e 100644
--- a/lib/gen_crc32table.c
+++ b/lib/gen_crc32table.c
@@ -2,30 +2,11 @@
#include <stdio.h>
#include "../include/linux/crc32poly.h"
#include "../include/generated/autoconf.h"
-#include "crc32defs.h"
#include <inttypes.h>
-#define ENTRIES_PER_LINE 4
-
-#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
-
-#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];
+static uint32_t crc32table_le[256];
+static uint32_t crc32table_be[256];
+static uint32_t crc32ctable_le[256];
/**
* crc32init_le() - allocate and initialize LE table data
@@ -34,25 +15,17 @@ static uint32_t crc32ctable_le[LE_TABLE_ROWS][256];
* fact that crctable[i^j] = crctable[i] ^ crctable[j].
*
*/
-static void crc32init_le_generic(const uint32_t polynomial,
- uint32_t (*tab)[256])
+static void crc32init_le_generic(const uint32_t polynomial, uint32_t tab[256])
{
unsigned i, j;
uint32_t crc = 1;
- tab[0][0] = 0;
+ tab[0] = 0;
- for (i = LE_TABLE_SIZE >> 1; i; i >>= 1) {
+ for (i = 128; i; i >>= 1) {
crc = (crc >> 1) ^ ((crc & 1) ? polynomial : 0);
- for (j = 0; j < LE_TABLE_SIZE; j += 2 * i)
- tab[0][i + j] = crc ^ tab[0][j];
- }
- for (i = 0; i < LE_TABLE_SIZE; i++) {
- crc = tab[0][i];
- for (j = 1; j < LE_TABLE_ROWS; j++) {
- crc = tab[0][crc & 0xff] ^ (crc >> 8);
- tab[j][i] = crc;
- }
+ for (j = 0; j < 256; j += 2 * i)
+ tab[i + j] = crc ^ tab[j];
}
}
@@ -74,34 +47,22 @@ static void crc32init_be(void)
unsigned i, j;
uint32_t crc = 0x80000000;
- crc32table_be[0][0] = 0;
+ crc32table_be[0] = 0;
- for (i = 1; i < BE_TABLE_SIZE; i <<= 1) {
+ for (i = 1; i < 256; i <<= 1) {
crc = (crc << 1) ^ ((crc & 0x80000000) ? CRC32_POLY_BE : 0);
for (j = 0; j < i; j++)
- crc32table_be[0][i + j] = crc ^ crc32table_be[0][j];
- }
- for (i = 0; i < BE_TABLE_SIZE; i++) {
- crc = crc32table_be[0][i];
- for (j = 1; j < BE_TABLE_ROWS; j++) {
- crc = crc32table_be[0][(crc >> 24) & 0xff] ^ (crc << 8);
- crc32table_be[j][i] = crc;
- }
+ crc32table_be[i + j] = crc ^ crc32table_be[j];
}
}
-static void output_table(uint32_t (*table)[256], int rows, int len, char *trans)
+static void output_table(const uint32_t table[256])
{
- int i, j;
-
- for (j = 0 ; j < rows; j++) {
- printf("{");
- for (i = 0; i < len - 1; i++) {
- if (i % ENTRIES_PER_LINE == 0)
- printf("\n");
- printf("%s(0x%8.8xL), ", trans, table[j][i]);
- }
- printf("%s(0x%8.8xL)},\n", trans, table[j][len - 1]);
+ int i;
+
+ for (i = 0; i < 256; i += 4) {
+ printf("\t0x%08x, 0x%08x, 0x%08x, 0x%08x,\n",
+ table[i], table[i + 1], table[i + 2], table[i + 3]);
}
}
@@ -109,34 +70,20 @@ int main(int argc, char** argv)
{
printf("/* this file is generated - do not edit */\n\n");
- if (CRC_LE_BITS > 1) {
- crc32init_le();
- 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");
- }
+ crc32init_le();
+ printf("static const u32 ____cacheline_aligned crc32table_le[256] = {\n");
+ output_table(crc32table_le);
+ printf("};\n");
- if (CRC_BE_BITS > 1) {
- crc32init_be();
- 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");
- }
+ crc32init_be();
+ printf("static const u32 ____cacheline_aligned crc32table_be[256] = {\n");
+ output_table(crc32table_be);
+ printf("};\n");
+
+ crc32cinit_le();
+ printf("static const u32 ____cacheline_aligned crc32ctable_le[256] = {\n");
+ output_table(crc32ctable_le);
+ printf("};\n");
return 0;
}