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/* { dg-do compile } */
/* { dg-options "-fdump-tree-crc-details" } */
/* { dg-skip-if "" { *-*-* } { "-O0" "-O1" "-Os" "-flto" } } */
#include <stdint.h>
uint16_t crc16_update(uint16_t crc, uint8_t a) {
int i;
uint16_t b;
for (i = 0; i < 8; ++i) {
if ((crc & 1) ^ (a & 1))
crc = (crc >> 1) ^ 0xa001;
else
crc = (crc >> 1);
a >>= 1;
b = crc; // In compiled version, b is outside of the loop.
}
uint16_t c = ++b;
return c;
}
/* { dg-final { scan-tree-dump "crc16_update 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 "calculates CRC!" "crc" } } */
/* { dg-final { scan-tree-dump "Polynomial's value is \\\{1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1\\\}" "crc" } } */
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