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SynacorVM
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#include <stdio.h> | |
#include <stdlib.h> | |
#define eval(v) (v < 32768u ? v : memory[v]) | |
static int pc, sp; | |
static unsigned short stack[1024]; | |
static unsigned short memory[(1ul << 15) + 8]; | |
static int | |
step(void) | |
{ | |
int in; | |
unsigned a, b, c, op = memory[pc++]; | |
switch (op) { | |
case 0: return 0; | |
case 1: a = memory[pc++]; | |
b = memory[pc++]; | |
memory[a] = eval(b); | |
return 1; | |
case 2: a = memory[pc++]; | |
stack[sp++] = eval(a); | |
return 1; | |
case 3: if (!sp) abort(); | |
a = memory[pc++]; | |
memory[a] = stack[--sp]; | |
return 1; | |
case 4: a = memory[pc++]; | |
b = memory[pc++]; | |
c = memory[pc++]; | |
memory[a] = eval(b) == eval(c); | |
return 1; | |
case 5: a = memory[pc++]; | |
b = memory[pc++]; | |
c = memory[pc++]; | |
memory[a] = eval(b) > eval(c); | |
return 1; | |
case 6: a = memory[pc]; | |
pc = eval(a); | |
return 1; | |
case 7: a = memory[pc++]; | |
b = memory[pc++]; | |
if (eval(a)) pc = eval(b); | |
return 1; | |
case 8: a = memory[pc++]; | |
b = memory[pc++]; | |
if (!eval(a)) pc = eval(b); | |
return 1; | |
case 9: a = memory[pc++]; | |
b = memory[pc++]; | |
c = memory[pc++]; | |
memory[a] = (eval(b) + eval(c)) % 32768u; | |
return 1; | |
case 10: a = memory[pc++]; | |
b = memory[pc++]; | |
c = memory[pc++]; | |
memory[a] = (eval(b) * eval(c)) % 32768u; | |
return 1; | |
case 11: a = memory[pc++]; | |
b = memory[pc++]; | |
c = memory[pc++]; | |
memory[a] = eval(b) % eval(c); | |
return 1; | |
case 12: a = memory[pc++]; | |
b = memory[pc++]; | |
c = memory[pc++]; | |
memory[a] = eval(b) & eval(c); | |
return 1; | |
case 13: a = memory[pc++]; | |
b = memory[pc++]; | |
c = memory[pc++]; | |
memory[a] = eval(b) | eval(c); | |
return 1; | |
case 14: a = memory[pc++]; | |
b = memory[pc++]; | |
memory[a] = ~eval(b) & 0x7fff; | |
return 1; | |
case 15: a = memory[pc++]; | |
b = memory[pc++]; | |
memory[a] = memory[eval(b)]; | |
return 1; | |
case 16: a = memory[pc++]; | |
b = memory[pc++]; | |
memory[eval(a)] = eval(b); | |
return 1; | |
case 17: a = memory[pc++]; | |
stack[sp++] = pc; | |
pc = eval(a); | |
return 1; | |
case 18: if (!sp) return 0; | |
pc = stack[--sp]; | |
return 1; | |
case 19: a = memory[pc++]; | |
putchar(eval(a)); | |
return 1; | |
case 20: in = getchar(); | |
if (in == EOF) abort(); | |
memory[memory[pc++]] = in; | |
return 1; | |
case 21: return 1; | |
} | |
abort(); | |
} | |
int | |
main(int argc, char *argv[]) | |
{ | |
FILE *f = fopen(argv[argc - 1], "rb"); | |
int i = 0; | |
for (;;) { | |
unsigned v; | |
int lo = fgetc(f); | |
int hi = fgetc(f); | |
if (lo == EOF) break; | |
if (hi == EOF) abort(); | |
v = (unsigned)hi << 8 | lo; | |
if (v > 32775) abort(); | |
memory[i++] = v; | |
} | |
fclose(f); | |
while (step()) | |
; | |
return 0; | |
} |
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