/* { dg-do compile } */
/* { dg-options "-fdump-tree-crc-details" } */
/* { dg-skip-if "" { *-*-* } { "-O0" "-O1" "-Os" "-flto" } } */

#define CRC16_CCITT     0x102
#define POLYNOM         CRC16_CCITT

unsigned int crc16 (unsigned int crcValue, unsigned char newByte) {
    unsigned char i;

    for (i = 0; i < 8; i++) {

        if (((crcValue & 0x8000) >> 8) ^ (newByte & 0x80)) {
            crcValue = (crcValue << 1) ^ POLYNOM;
        } else {
            crcValue = (crcValue << 1);
        }

        newByte <<= 1;
    }

    return crcValue;
}

/* { dg-final { scan-tree-dump "function maybe contains CRC calculation." "crc" } } */
/* { dg-final { scan-tree-dump "Loop iteration number is 7" "crc" } } */
/* { dg-final { scan-tree-dump "Bit forward" "crc" } } */
/* { dg-final { scan-tree-dump "Polynomial's value is \\\{\[0, \]*1, 0, 0, 0, 0, 0, 0, 1, 0\\\}" "crc" } } */