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/* Code generation for comparisons */
#include <stdio.h>
unsigned int f(int x, unsigned int y, char * z)
{
unsigned int r = 0;
/* Without explicit comparison */
if (x) r |= 1;
if (y) r |= 2;
if (z) r |= 4;
/* Negated comparisons */
if (!x) r |= 8;
if (!y) r |= 0x10;
if (!z) r |= 0x20;
/* Explicit comparisons against 0 */
if (x == 0) r |= 0x40;
if (y == 0) r |= 0x80;
if (z == 0) r |= 0x100;
if (x != 0) r |= 0x200;
if (y != 0) r |= 0x400;
if (z != 0) r |= 0x800;
/* With masks */
if (x & 1) r |= 0x1000;
if (!(x & 2)) r |= 0x2000;
if ((x & 4) == 0) r |= 0x4000;
if ((x & 8) != 0) r |= 0x8000;
return r;
}
/* Same, but we compute the boolean value of the tests */
unsigned int g(int x, unsigned int y, char * z)
{
unsigned int r = 0;
#define MERGE(tst) r = (r << 1) | (tst)
/* Without explicit comparison */
MERGE((_Bool) x);
MERGE((_Bool) y);
MERGE((_Bool) z);
/* Negated comparisons */
MERGE((_Bool) !x);
MERGE((_Bool) !y);
MERGE((_Bool) !z);
/* Explicit comparisons against 0 */
MERGE(x == 0);
MERGE(y == 0);
MERGE(z == 0);
MERGE(x != 0);
MERGE(y != 0);
MERGE(z != 0);
/* With masks */
MERGE((_Bool) (x & 1));
MERGE(! (x & 2));
MERGE((x & 4) == 0);
MERGE((x & 8) != 0);
return r;
}
int main(void)
{
printf("f(0, 0, 0) = 0x%x\n", f(0, 0, 0));
printf("g(0, 0, 0) = 0x%x\n", g(0, 0, 0));
printf("f(12, 1, \"x\") = 0x%x\n", f(12, 1, "x"));
printf("g(12, 1, \"x\") = 0x%x\n", g(12, 1, "x"));
return 0;
}
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