mirror of
https://github.com/RaySollium99/picodrive.git
synced 2025-09-05 15:27:46 -04:00
03c5768cb5
git-svn-id: file:///home/notaz/opt/svn/PicoDrive@181 be3aeb3a-fb24-0410-a615-afba39da0efa
120 lines
2.3 KiB
C
120 lines
2.3 KiB
C
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <time.h>
|
|
|
|
|
|
static FILE *f;
|
|
|
|
#define bswap16(x) (x=(unsigned short)((x<<8)|(x>>8)))
|
|
#define bswap32(x) (x=((x<<24)|((x<<8)&0xff0000)|((x>>8)&0x00ff00)|((unsigned)x>>24)))
|
|
|
|
static void write_op(unsigned short op, unsigned short word0, unsigned short word1, unsigned short word2)
|
|
{
|
|
bswap16(op);
|
|
bswap16(word0);
|
|
bswap16(word1);
|
|
bswap16(word2);
|
|
|
|
fwrite(&op, 1, sizeof(op), f);
|
|
fwrite(&word0, 1, sizeof(word0), f);
|
|
fwrite(&word1, 1, sizeof(word1), f);
|
|
fwrite(&word2, 1, sizeof(word2), f);
|
|
}
|
|
|
|
static void write32(unsigned int a)
|
|
{
|
|
bswap32(a);
|
|
fwrite(&a, 1, sizeof(a), f);
|
|
}
|
|
|
|
static int op_check(unsigned short op)
|
|
{
|
|
if ((op&0xf000) == 0x6000) return 0; // Bxx
|
|
if ((op&0xf0f8) == 0x50c8) return 0; // DBxx
|
|
if ((op&0xff80) == 0x4e80) return 0; // Jsr
|
|
if ((op&0xf000) == 0xa000) return 0; // a-line
|
|
if ((op&0xf000) == 0xf000) return 0; // f-line
|
|
if ((op&0xfff8)==0x4e70&&op!=0x4e71&&op!=0x4e76) return 0; // reset, rte, rts
|
|
|
|
if ((op&0x3f) >= 0x28) op = (op&~0x3f) | (rand() % 0x28);
|
|
return 1;
|
|
}
|
|
|
|
static unsigned short safe_rand(void)
|
|
{
|
|
unsigned short op;
|
|
|
|
/* avoid branch opcodes */
|
|
do
|
|
{
|
|
op = rand();
|
|
}
|
|
while (!op_check(op));
|
|
|
|
return op;
|
|
}
|
|
|
|
int main()
|
|
{
|
|
int i, op;
|
|
|
|
srand(time(0));
|
|
|
|
f = fopen("test_misc2.bin", "wb");
|
|
if (!f) return 1;
|
|
|
|
write32(0x00ff8000); // stack
|
|
write32(0x300); // IP
|
|
|
|
for (i=0x100/4-2; i; i--)
|
|
{
|
|
write32(0x200+i*4); // exception vectors
|
|
}
|
|
|
|
for (i=0x100/4; i; i--)
|
|
{
|
|
write32(0); // pad
|
|
}
|
|
|
|
for (i=0x100/4; i; i--)
|
|
{
|
|
write32(0x4e734e73); // fill with rte instructions
|
|
}
|
|
|
|
for (op = 0; op < 0x10000; op++)
|
|
{
|
|
if ((op&0xf000) == 0x6000) // Bxx
|
|
{
|
|
if ((op&0x00ff) == 0)
|
|
write_op(op, 6, 0, 0);
|
|
else if ((op&0x00ff) == 0xff)
|
|
write_op(op, 0, 6, 0);
|
|
}
|
|
else if ((op&0xf0f8)==0x50c8) // DBxx
|
|
{
|
|
write_op(op, 6, 0, 0);
|
|
}
|
|
else if ((op&0xff80)==0x4e80) // Jsr
|
|
{
|
|
int addr = 0x300 + i*8 + 8;
|
|
if ((op&0x3f) == 0x39)
|
|
write_op(op, addr >> 16, addr & 0xffff, 0);
|
|
}
|
|
else if ((op&0xf000)==0xa000 || (op&0xf000)==0xf000) // a-line, f-line
|
|
{
|
|
if (op != 0xa000 && op != 0xf000) continue;
|
|
}
|
|
else if ((op&0xfff8)==0x4e70&&op!=0x4e71&&op!=0x4e76); // rte, rts, stop, reset
|
|
else
|
|
{
|
|
write_op(op, safe_rand(), safe_rand(), safe_rand());
|
|
}
|
|
}
|
|
|
|
// jump to the beginning
|
|
write_op(0x4ef8, 0x300, 0, 0);
|
|
|
|
fclose(f);
|
|
return 0;
|
|
}
|
|
|