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otrx: make crc32 table global for further optimizations

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So far we got only one generic function accessing this table, but
implementing optimizations will require calculating crc32 in other code
parts as well.

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>

SVN-Revision: 46077
This commit is contained in:
Rafał Miłecki
2015-06-20 21:11:56 +00:00
parent 933b588e25
commit c13dede6b1
1 changed files with 68 additions and 67 deletions
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7
package/utils/otrx/src/otrx.c
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@@ -48,8 +48,7 @@ char *partition[TRX_MAX_PARTS] = {};
* CRC32
**************************************************/
uint32_t otrx_crc32(uint8_t *buf, size_t len) {
static const uint32_t t[] = {
static const uint32_t crc32_tbl[] = {
0x00000000, 0x77073096, 0xee0e612c, 0x990951ba,
0x076dc419, 0x706af48f, 0xe963a535, 0x9e6495a3,
0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988,
@@ -115,10 +114,12 @@ uint32_t otrx_crc32(uint8_t *buf, size_t len) {
0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94,
0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d,
};
uint32_t otrx_crc32(uint8_t *buf, size_t len) {
uint32_t crc = 0xffffffff;
while (len) {
crc = t[(crc ^ *buf) & 0xff] ^ (crc >> 8);
crc = crc32_tbl[(crc ^ *buf) & 0xff] ^ (crc >> 8);
buf++;
len--;
}