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#include <stdint.h>
#include <stdio.h>
static const int S[] = {1, 2, 4, 8, 16}; // Magic Binary Numbers
static const int B[] = {0x55555555, 0x33333333, 0x0F0F0F0F, 0x00FF00FF, 0x0000FFFF};
char* utb(uint32_t x) {
static char rep[36];
int cnt = 34;
for (int i = 0; i < 32; i += 1) {
if (i > 0 && i % 8 == 0) {
rep[cnt] = ' ';
cnt -= 1;
}
rep[cnt] = (x & 1) + '0';
cnt -= 1;
x >>= 1;
}
rep[35] = '\0';
return rep;
}
void pb(uint32_t x) {
printf("%s : %d\n", utb(x), x);
}
struct A {
int8_t a;
void *b;
int8_t c;
int16_t d;
};
struct B {
void *c;
double b;
int16_t a;
};
struct C {
int8_t a;
int8_t c;
int16_t d;
void *b;
};
// zaklada count > 0
void secret(uint8_t *to, uint8_t *from, size_t count) {
size_t n = (count + 7) / 8;
switch (count % 8) {
case 0: do { *to++ = *from++;
case 7: *to++ = *from++;
case 6: *to++ = *from++;
case 5: *to++ = *from++;
case 4: *to++ = *from++;
case 3: *to++ = *from++;
case 2: *to++ = *from++;
case 1: *to++ = *from++;
} while (--n > 0);
}
}
// zaklada count > 0
void goto_secret(uint8_t *to, uint8_t *from, size_t count) {
size_t n = (count + 7) / 8;
static void *array[] = { &&finito, &&c0, &&c1, &&c2, &&c3, &&c4, &&c5, &&c6, &&c7 };
goto *array[count % 8 + 1];
c0: *to++ = *from++;
c7: *to++ = *from++;
c6: *to++ = *from++;
c5: *to++ = *from++;
c4: *to++ = *from++;
c3: *to++ = *from++;
c2: *to++ = *from++;
c1: *to++ = *from++;
goto *array[(--n > 0)];
finito: return;
}
int main() {
/* Zadanie 1 */
printf("Zadanie 1:\n");
uint32_t i = 7, k = 15, x = 15689126;
pb(x);
uint32_t c = (((1<<i) & x) >> i) << k; // 0010 0000
x = (x & ~(1<<k)) | c;
pb(x);
/* Zadanie 2 */
printf("Zadanie 2:\n");
uint32_t v = 312866134;
pb(v);
// wersja prosta
c = v - ((v >> 1) & B[0]); pb(c);
c = ((c >> S[1]) & B[1]) + (c & B[1]); pb(c);
c = ((c >> S[2]) + c) & B[2]; pb(c);
c = ((c >> S[3]) + c) & B[3]; pb(c);
c = ((c >> S[4]) + c) & B[4]; pb(c);
printf("-----------------\n");
// wersja dla koksow
v = v - ((v >> 1) & 0x55555555); pb(v);// reuse input as temporary
v = ((v >> 2) & 0x33333333) + (v & 0x33333333); pb(v); // temp
c = ((v + (v >> 4) & 0xF0F0F0F) * 0x1010101) >> 24; pb(c); // count
/* Zadanie 3 */
printf("Zadanie 3:\n");
struct A a;
struct B b;
struct C d;
int8_t x1;
void *x2;
int16_t x3;
printf("%lu %lu %lu\n", sizeof x1, sizeof x2, sizeof x3);
printf("%lu %lu %lu\n", sizeof a, sizeof b, sizeof d);
/* Zadanie 4 */
/* Zadanie 5 */
/* s += b[j + 1] + b[--j];
*
* t1 := j + 1
* t2 := t1 * 4
* t3 := b[t2]
* j := j - 1
* t4 := j * 4
* t5 := b[t4]
* t6 := t4 + t5 // Czy na pewno tak?
* s := s + t6
*
* a[i++] -= *b * (c[j*2] + 1);
*
* t1 := *b
* t2 := j * 2
* t3 := t2 * 4
* t4 := c[t3]
* t5 := t4 + 1
* t6 := t1 * t5
* a := a - t6
* i := i + 1
*/
/* Zadanie 6 */
/* vs->d = us[1].a + us[j].c;
* t1 := 1 * 12
* t2 := us + t1
* t2' := us + 0 // chcemy dostać się do a, ale jest na poczatku, wiec nic dodawac nie trzeba
* t3 := *t2
* t4 := j * 12
* t5 := us + t4
* t6 := t5 + 8
* t7 := *t6
* t8 := t3 + t7
* t9 := vs + 9
* *t9 := t8
*/
/* Zadanie 7 */
/* I := 0 ; <<B1>>
goto ITest
ILoop: J := I ; <<B2>>
goto WTest
WLoop: t1 := 4 * J ; <<B3>>
Temp := arr[t1] ; arr[J]
t2 := J - 1
t3 := 4 * t2
t4 := arr[t3] ; arr[J - 1]
arr[t1] := t4 ; arr[J] := arr[J - 1]
arr[t3] := Temp ; arr[J - 1] := Temp
J := J - 1
WTest: if J <= 0 goto IPlus ; <<B4>>
t4 := 4 * J ; <<B5>>
t5 := arr[t4]
t6 := J - 1
t7 = 4 * t6
t8 := arr[t7]
if t5 >= t8 goto IPlus
goto WLoop ; <<B6>>
IPlus: I := I + 1 ; <<B7>>
ITest: if I < length goto ILoop ; <<B8>>
*/
/* Zadanie 8 */
printf("Zadanie 8:\n");
// secret kopiuje wartości na które wskazuje from do miejsca w które wskazuje to,
// przesuwa oba wskaźniki i powtarza tak count razy (czyli efektywnie kopiuje np. tablice)
uint8_t t1[10] = {1,2,3,0,5,100,7,8,9,10}, t2[10];
uint8_t* to = t2 + 2, *from = t1 + 3;
size_t count = 4;
goto_secret(to, from, count);
for (int i = 0; i < 10; i++)
printf("%hhd ", t1[i]);
printf("\n");
for (int i = 0; i < 10; i++)
printf("%hhd ", t2[i]);
printf("\n");
i = 3;
t1[i++] = i;
printf("%hhd\n", t1[i-1]);
}
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