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/* Fun with builtins */
#include <stdio.h>
unsigned int x = 0x12345678;
unsigned int y = 0xDEADBEEF;
unsigned long long xx = 0x1234567812345678ULL;
double a = 3.14159;
unsigned short s = 0x1234;
int main(int argc, char ** argv)
{
unsigned z;
printf("bswap(%x) = %x\n", x, __builtin_bswap(x));
printf("bswap16(%x) = %x\n", s, __builtin_bswap16(s));
printf("clz(%x) = %d\n", x, __builtin_clz(x));
printf("clzll(%llx) = %d\n", (unsigned long long) x, __builtin_clzll(x));
printf("clzll(%llx) = %d\n", xx, __builtin_clzll(xx));
z = __builtin_bswap(x);
printf("clzll(%lx) = %d\n", z, __builtin_clzll(z));
printf("fsqrt(%f) = %f\n", a, __builtin_fsqrt(a));
printf ("read_16_rev = %x\n", __builtin_read16_reversed(&s));
printf ("read_32_rev = %x\n", __builtin_read32_reversed(&y));
__builtin_write16_reversed(&s, 0x789A);
printf ("after write_16_rev: %x\n", s);
__builtin_write32_reversed(&y, 0x12345678);
printf ("after write_32_rev: %x\n", y);
y = 0;
__builtin_write32_reversed(&y, 0x12345678);
printf ("CSE write_32_rev: %s\n", y == 0x78563412 ? "ok" : "ERROR");
/* Make sure that ignoring the result of a builtin
doesn't cause an internal error */
(void) __builtin_bswap(x);
(void) __builtin_fsqrt(a);
return 0;
}
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