Something looks dirty with folding, the origin diff is following: 0000000000000018 <chksum_update>: 0000000000000018 <chksum_update>: ; ctx->crc = crc32_mips_le_hw(ctx->crc, data, length); ; ctx->crc = crc32_mips_le_hw(ctx->crc, data, length); 18: 08 00 82 8c lw $2, 0x8($4) 18: 08 00 82 8c lw $2, 0x8($4) ; while (len >= sizeof(u64)) { ; while (len >= sizeof(u64)) { 1c: 08 00 c1 2c sltiu $1, $6, 0x8 <chksum_init+0x8> 1c: 08 00 c1 2c sltiu $1, $6, 0x8 <chksum_init+0x8> 20: 06 00 20 f8 bnezc $1, 0x3c <chksum_update+0x24> 20: 06 00 20 f8 bnezc $1, 0x3c <chksum_update+0x24> ; return le64_to_cpu(__get_unaligned_t(__le64, p)); ; return le64_to_cpu(__get_unaligned_t(__le64, p)); 24: 00 00 a3 dc ld $3, 0x0($5) 24: 00 00 a3 dc ld $3, 0x0($5) ; CRC32(crc, value, d); ; CRC32(crc, value, d); 28: cf 00 62 7c <unknown> crc32d v0,v1,v0 28: cf 00 62 7c <unknown> crc32d v0,v1,v0 ; len -= sizeof(u64); ; len -= sizeof(u64); 2c: f8 ff c6 24 addiu $6, $6, -0x8 <chksumc_digest+0xfffffffffffffce0> 2c: f8 ff c6 24 addiu $6, $6, -0x8 <chksumc_digest+0xfffffffffffffd48> ; while (len >= sizeof(u64)) { ; while (len >= sizeof(u64)) { 30: 08 00 c1 2c sltiu $1, $6, 0x8 <chksum_init+0x8> 30: 08 00 c1 2c sltiu $1, $6, 0x8 <chksum_init+0x8> 34: fb ff 20 10 beqz $1, 0x24 <chksum_update+0xc> 34: fb ff 20 10 beqz $1, 0x24 <chksum_update+0xc> 38: 08 00 a5 64 daddiu $5, $5, 0x8 <chksum_init+0x8> 38: 08 00 a5 64 daddiu $5, $5, 0x8 <chksum_init+0x8> ; if (len & sizeof(u32)) { ; if (len & sizeof(u32)) { 3c: 04 00 c1 2c sltiu $1, $6, 0x4 <chksum_init+0x4> 3c: 04 00 c1 2c sltiu $1, $6, 0x4 <chksum_init+0x4> 40: 0a 00 20 10 beqz $1, 0x6c <chksum_update+0x54> 40: 04 00 20 f8 bnezc $1, 0x54 <chksum_update+0x3c> 44: 03 f8 c3 7c dext $3, $6, 0x0, 0x20 <chksum_update+0x8> ; return le32_to_cpu(__get_unaligned_t(__le32, p)); ; if (len & sizeof(u16)) { 44: 00 00 a3 8c lw $3, 0x0($5) 48: 02 00 61 30 andi $1, $3, 0x2 <chksum_init+0x2> ; CRC32(crc, value, w); 4c: 0c 00 20 f8 bnezc $1, 0x80 <chksum_update+0x68> ; if (len & sizeof(u8)) { 48: 8f 00 62 7c <unknown> crc32w v0,v1,v0 50: 01 00 61 30 andi $1, $3, 0x1 <chksum_init+0x1> 54: 02 00 20 d8 beqzc $1, 0x60 <chksum_update+0x48> ; len -= sizeof(u32); ; CRC32(crc, value, b); 4c: fc ff c6 24 addiu $6, $6, -0x4 <chksumc_digest+0xfffffffffffffd4c> 58: 00 00 a3 90 lbu $3, 0x0($5) ; p += sizeof(u32); 50: 04 00 a5 64 daddiu $5, $5, 0x4 <chksum_init+0x4> 5c: 0f 00 62 7c <unknown> crc32b v0,v1,v0 ; if (len & sizeof(u16)) { 54: 03 f8 c3 7c dext $3, $6, 0x0, 0x20 <chksum_update+0x8> ; ctx->crc = crc32_mips_le_hw(ctx->crc, data, length); 58: 02 00 61 30 andi $1, $3, 0x2 <chksum_init+0x2> 60: 08 00 82 ac sw $2, 0x8($4) 5c: 03 00 20 d8 beqzc $1, 0x6c <chksum_update+0x54> ; return 0; ; CRC32(crc, value, h); 64: 09 00 e0 03 jr $ra 60: 00 00 a6 94 lhu $6, 0x0($5) 68: 00 00 02 64 daddiu $2, $zero, 0x0 <chksum_init> ; return le32_to_cpu(__get_unaligned_t(__le32, p)); 64: 4f 00 c2 7c <unknown> crc32h v0,a2,v0 6c: 00 00 a6 8c lw $6, 0x0($5) ; CRC32(crc, value, w); ; p += sizeof(u16); 70: 8f 00 c2 7c <unknown> crc32w v0,a2,v0 68: 02 00 a5 64 daddiu $5, $5, 0x2 <chksum_init+0x2> ; if (len & sizeof(u16)) { ; if (len & sizeof(u8)) { 74: 02 00 61 30 andi $1, $3, 0x2 <chksum_init+0x2> 6c: 01 00 61 30 andi $1, $3, 0x1 <chksum_init+0x1> 78: f5 ff 20 10 beqz $1, 0x50 <chksum_update+0x38> 70: 02 00 20 d8 beqzc $1, 0x7c <chksum_update+0x64> 7c: 04 00 a5 64 daddiu $5, $5, 0x4 <chksum_init+0x4> ; CRC32(crc, value, h); ; CRC32(crc, value, b); 80: 00 00 a6 94 lhu $6, 0x0($5) 74: 00 00 a3 90 lbu $3, 0x0($5) 84: 4f 00 c2 7c <unknown> crc32h v0,a2,v0 78: 0f 00 62 7c <unknown> crc32b v0,v1,v0 ; if (len & sizeof(u8)) { ; ctx->crc = crc32_mips_le_hw(ctx->crc, data, length); 88: 01 00 61 30 andi $1, $3, 0x1 <chksum_init+0x1> 7c: 08 00 82 ac sw $2, 0x8($4) 8c: f4 ff 20 10 beqz $1, 0x60 <chksum_update+0x48> ; return 0; 90: 02 00 a5 64 daddiu $5, $5, 0x2 <chksum_init+0x2> 80: 09 00 e0 03 jr $ra 94: 00 00 00 08 j 0x0 <chksum_init> 84: 00 00 02 64 daddiu $2, $zero, 0x0 <chksum_init> Guan Wentao