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#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
#include <string.h>
#include "../endian.h"
static inline int bit(void * p, unsigned bitno)
{
unsigned byteno = bitno / 8;
#ifdef ARCH_BIG_ENDIAN
unsigned bit_in_byte = 7 - (bitno & 7);
#else
unsigned bit_in_byte = bitno & 7;
#endif
return (((unsigned char *) p)[byteno] >> bit_in_byte) & 1;
}
void print_prologue(char * name, size_t al, size_t sz)
{
printf("%s: align %d, sizeof %d, layout", name, (int)al, (int)sz);
}
void print_next_field(_Bool first, size_t sz, void * p)
{
static unsigned pos;
if (first) pos = 0;
/* Find first bit set, starting with [pos] */
while (1) {
assert (pos < 8 * sz);
if (bit(p, pos)) break;
pos += 1;
}
/* Print this position */
printf(" %u", pos);
/* Skip over one bits */
while (pos < 8 * sz && bit(p, pos)) pos++;
}
void print_epilogue(void)
{
printf("\n");
}
#define TEST4(s) \
struct s x; \
memset(&x, 0, sizeof(x)); \
print_prologue(#s, _Alignof(struct s), sizeof(x)); \
x.a = -1; print_next_field(1, sizeof(x), &x); \
x.b = -1; print_next_field(0, sizeof(x), &x); \
x.c = -1; print_next_field(0, sizeof(x), &x); \
x.d = -1; print_next_field(0, sizeof(x), &x); \
print_epilogue();
int main()
{
#include "layout.h"
return 0;
}
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