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35 #ifndef _RTE_HASH_CRC_H_
36 #define _RTE_HASH_CRC_H_
51 * Use single crc32 instruction to perform a hash on a 4 byte value.
54 * Data to perform hash on.
56 * Value to initialise hash generator.
58 * 32bit calculated hash value.
60 static inline uint32_t
61 rte_hash_crc_4byte(uint32_t data, uint32_t init_val)
63 asm volatile("crc32 %[data], %[init_val]"
64 : [init_val]"=r" (init_val)
65 : [data]"r" (data), "[init_val]" (init_val));
70 * Use crc32 instruction to perform a hash.
73 * Data to perform hash on.
75 * How many bytes to use to calculate hash value.
77 * Value to initialise hash generator.
79 * 32bit calculated hash value.
81 static inline uint32_t
82 rte_hash_crc(const void *data, uint32_t data_len, uint32_t init_val)
86 const uint32_t *p32 = (const uint32_t *)data;
88 for (i = 0; i < data_len / 4; i++) {
89 init_val = rte_hash_crc_4byte(*p32++, init_val);
92 switch (3 - (data_len & 0x03)) {
94 temp |= *((const uint8_t *)p32 + 2) << 16;
97 temp |= *((const uint8_t *)p32 + 1) << 8;
100 temp |= *((const uint8_t *)p32);
101 init_val = rte_hash_crc_4byte(temp, init_val);
113 #endif /* _RTE_HASH_CRC_H_ */