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#include <inttypes.h>
#include <stdio.h>
#define LONGx1 "8192"
#define LONGx2 "16384"
void main(void) {
const char *n = "abcdefghijklmnopqrstuvwxyz0123456789";
uint64_t c0 = 0, c1 = 1, c2 = 2;
uint64_t s;
uint32_t eax = 1, ecx;
__asm__("cpuid" : "=c"(ecx) : "a"(eax) : "%ebx", "%edx");
__asm__(
"crc32b\t"
"(%1), %0"
: "=r"(c0)
: "r"(n), "0"(c0));
__asm__(
"crc32q\t"
"(%3), %0\n\t"
"crc32q\t" LONGx1
"(%3), %1\n\t"
"crc32q\t" LONGx2 "(%3), %2"
: "=r"(c0), "=r"(c1), "=r"(c2)
: "r"(n), "0"(c0), "1"(c1), "2"(c2));
s = c0 + c1 + c2;
printf("avoiding unused code removal by printing %d, %d, %d\n", (int)s,
(int)eax, (int)ecx);
}
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