cpu.c
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//
// Created by imanol on 12/25/16.
//
#include <stdlib.h>
#include "cpu.h"
void mov(uint16_t dst, uint16_t src)
{
if(src > MAX_INT)
{
regs[dst % (MAX_INT+1)] = regs[src % (MAX_INT+1)];
}
else
{
regs[dst % (MAX_INT+1)] = src;
}
}
void push(uint16_t src)
{
if(src > MAX_INT)
{
stack_push(regs[src % (MAX_INT+1)]);
}
else
{
stack_push(src);
}
}
void pop(uint16_t dst)
{
uint16_t value = stack_pop();
if(STACK_FAULT)
{
fprintf(stderr,"CRITICAL: STACK VIOLATION\n");
core_dump();
}
regs[dst % (MAX_INT+1)] = value;
}
void teq(uint16_t dst, uint16_t a, uint16_t b)
{
if(a > MAX_INT)
{
a = regs[a % (MAX_INT+1)];
}
if(b > MAX_INT)
{
b = regs[b % (MAX_INT+1)];
}
regs[dst % (MAX_INT+1)] = (a == b);
}
void tgt(uint16_t dst, uint16_t a, uint16_t b)
{
if(a > MAX_INT)
{
a = regs[a % (MAX_INT+1)];
}
if(b > MAX_INT)
{
b = regs[b % (MAX_INT+1)];
}
regs[dst % (MAX_INT+1)] = (a > b);
}
void jmp(uint16_t dst)
{
if(dst > MAX_INT)
{
pc = regs[dst % (MAX_INT+1)];
}
else
{
pc = dst;
}
}
void jnz(uint16_t cond, uint16_t dst)
{
if(cond > MAX_INT)
{
cond = regs[cond % (MAX_INT+1)];
}
if(cond)
{
jmp(dst);
}
}
void jz(uint16_t cond, uint16_t dst)
{
if(cond > MAX_INT)
{
cond = regs[cond % (MAX_INT+1)];
}
if(!cond)
{
jmp(dst);
}
}
void add(uint16_t dst, uint16_t a, uint16_t b)
{
if(a > MAX_INT)
{
a = regs[a % (MAX_INT+1)];
}
if(b > MAX_INT)
{
b = regs[b % (MAX_INT+1)];
}
regs[dst % (MAX_INT+1)] = (a + b) % (MAX_INT+1);
}
void mul(uint16_t dst, uint16_t a, uint16_t b)
{
if(a > MAX_INT)
{
a = regs[a % (MAX_INT+1)];
}
if(b > MAX_INT)
{
b = regs[b % (MAX_INT+1)];
}
regs[dst % (MAX_INT+1)] = (a * b) % (MAX_INT+1);
}
void mod(uint16_t dst, uint16_t a, uint16_t b)
{
if(a > MAX_INT)
{
a = regs[a % (MAX_INT+1)];
}
if(b > MAX_INT)
{
b = regs[b % (MAX_INT+1)];
}
regs[dst % (MAX_INT+1)] = (a % b);
}
void and(uint16_t dst, uint16_t a, uint16_t b)
{
if(a > MAX_INT)
{
a = regs[a % (MAX_INT+1)];
}
if(b > MAX_INT)
{
b = regs[b % (MAX_INT+1)];
}
regs[dst % (MAX_INT+1)] = (a & b);
}
void or(uint16_t dst, uint16_t a, uint16_t b)
{
if(a > MAX_INT)
{
a = regs[a % (MAX_INT+1)];
}
if(b > MAX_INT)
{
b = regs[b % (MAX_INT+1)];
}
regs[dst % (MAX_INT+1)] = (a | b);
}
void not(uint16_t dst, uint16_t src)
{
if(src > MAX_INT)
{
src = regs[src % (MAX_INT+1)];
}
regs[dst % (MAX_INT+1)] = ~src & 0x7FFF;
}
void load(uint16_t dst, uint16_t src)
{
if(src > MAX_INT)
{
src = regs[src % (MAX_INT+1)];
}
regs[dst % (MAX_INT+1)] = mem[src];
}
void stor(uint16_t dst, uint16_t src)
{
if(src > MAX_INT)
{
src = regs[src % (MAX_INT+1)];
}
if(dst > MAX_INT)
{
mem[regs[dst % (MAX_INT+1)]] = src;
}
else
{
mem[dst] = src;
}
}
void call(uint16_t dst)
{
stack_push(pc);
jmp(dst);
}
uint8_t ret()
{
pc = stack_pop();
return STACK_FAULT;
}
void out(uint16_t src)
{
if(src > MAX_INT)
{
src = regs[src % (MAX_INT+1)];
}
putchar(src);
}
void in(uint16_t dst)
{
int c = getchar();
regs[dst % (MAX_INT + 1)] = (uint16_t)c;
}
void nop()
{
return;
}
uint16_t fetch()
{
uint16_t value = mem[pc++];
return value;
}
void decode_instruction(uint16_t opcode, uint16_t *arg1, uint16_t *arg2, uint16_t *arg3)
{
switch(opcode)
{
case HALT:
case RET:
case NOP:
break;
case PUSH:
case POP:
case JMP:
case CALL:
case OUT:
case IN:
*arg1 = fetch();
break;
case MOV:
case JNZ:
case JZ:
case NOT:
case LOAD:
case STOR:
*arg1 = fetch();
*arg2 = fetch();
break;
case TEQ:
case TGT:
case ADD:
case MUL:
case MOD:
case AND:
case OR:
*arg1 = fetch();
*arg2 = fetch();
*arg3 = fetch();
break;
default:
break;
}
}
uint8_t execute_instruction(uint16_t opcode, uint16_t arg1, uint16_t arg2, uint16_t arg3)
{
switch(opcode)
{
case HALT:
return 1;
case MOV:
mov(arg1,arg2);
break;
case PUSH:
push(arg1);
break;
case POP:
pop(arg1);
break;
case TEQ:
teq(arg1,arg2,arg3);
break;
case TGT:
tgt(arg1,arg2,arg3);
break;
case JMP:
jmp(arg1);
break;
case JNZ:
jnz(arg1,arg2);
break;
case JZ:
jz(arg1,arg2);
break;
case ADD:
add(arg1,arg2,arg3);
break;
case MUL:
mul(arg1,arg2,arg3);
break;
case MOD:
mod(arg1,arg2,arg3);
break;
case AND:
and(arg1,arg2,arg3);
break;
case OR:
or(arg1,arg2,arg3);
break;
case NOT:
not(arg1,arg2);
break;
case LOAD:
load(arg1,arg2);
break;
case STOR:
stor(arg1,arg2);
break;
case CALL:
call(arg1);
break;
case RET:
if(ret())
{
return 1;
}
break;
case OUT:
out(arg1);
break;
case IN:
in(arg1);
break;
case NOP:
nop();
break;
default:
fprintf(stderr,"CRITICAL: UNKNOWN OPCODE %2x FOUND IN %2x\n",opcode,pc);
core_dump();
break;
}
return 0;
}
void start_execution()
{
uint16_t arg1;
uint16_t arg2;
uint16_t arg3;
for(;;)
{
uint16_t opcode = fetch();
decode_instruction(opcode, &arg1, &arg2, &arg3);
if(execute_instruction(opcode, arg1, arg2, arg3))
{
return;
}
}
}
void core_dump()
{
print_regs();
uint16_t memdump[MEMSIZE];
uint16_t *stackdump;
dump_memory(memdump);
uint32_t stacksize = stack_dump(&stackdump);
FILE *fpm = fopen("synacor.mem","w");
FILE *fps = fopen("synacor.stack","w");
fwrite(memdump,MEMSIZE,sizeof(uint16_t),fpm);
fwrite(stackdump,stacksize,sizeof(uint16_t),fps);
fclose(fpm);
fclose(fps);
exit(1);
}