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/* { dg-do compile } */
/* { dg-options "-fdump-tree-crc-details" } */
/* { dg-skip-if "" { *-*-* } { "-O0" "-O1" "-Os" "-O3" "-flto" } } */
/* { dg-require-effective-target int32plus } */
//We don't verify this case as for the CRC unsigned int (32 bit) is used and
// the polynomial fits into 16 bit. Also, as the loop's iteration number and
// data's size differ.
unsigned short crc16 (char *data_p, unsigned short length) {
unsigned char i;
unsigned int data;
unsigned int crc = 0xffff;
if (length == 0)
return (~crc);
do {
for (i = 0, data = (unsigned int) 0xff & *data_p++;
i < 8;
i++, data >>= 1) {
if ((crc & 0x0001) ^ (data & 0x0001))
crc = (crc >> 1) ^ 0x8408;
else crc >>= 1;
}
} while (--length);
crc = ~crc;
data = crc;
crc = (crc << 8) | (data >> 8 & 0xff);
return (crc);
}
/* { 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 reversed" "crc" } } */
/* { dg-final { scan-tree-dump "Loop iteration number and data's size differ." "crc" } } */
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