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34 #ifndef _RTE_HASH_CRC_H_
35 #define _RTE_HASH_CRC_H_
48 #include <nmmintrin.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 return _mm_crc32_u32(init_val, data);
67 * Use crc32 instruction to perform a hash.
70 * Data to perform hash on.
72 * How many bytes to use to calculate hash value.
74 * Value to initialise hash generator.
76 * 32bit calculated hash value.
78 static inline uint32_t
79 rte_hash_crc(const void *data, uint32_t data_len, uint32_t init_val)
83 const uint32_t *p32 = (const uint32_t *)data;
85 for (i = 0; i < data_len / 4; i++) {
86 init_val = rte_hash_crc_4byte(*p32++, init_val);
89 switch (3 - (data_len & 0x03)) {
91 temp |= *((const uint8_t *)p32 + 2) << 16;
94 temp |= *((const uint8_t *)p32 + 1) << 8;
97 temp |= *((const uint8_t *)p32);
98 init_val = rte_hash_crc_4byte(temp, init_val);
110 #endif /* _RTE_HASH_CRC_H_ */