Files
paco/vm.cpp

92 lines
2.1 KiB
C++

#include "vm.h"
#define MAX_EXTERNAL_CALLS 256
#define MAX_DATA_STACK 256
#define MAX_CALL_STACK 256
enum OPS {
OP_NOP = 0,
OP_PUSH,
OP_POP,
OP_DUP,
OP_LOAD,
OP_STORE,
OP_JMP,
OP_JNT,
OP_JTR,
OP_JSR,
OP_RET,
OP_CALL,
OP_ADD,
OP_SUB,
OP_MUL,
OP_DIV,
OP_MOD,
OP_AND,
OP_OR,
OP_NOT,
OP_NEG,
OP_INC,
OP_EQ,
OP_NEQ,
OP_LT,
OP_GT
};
typedef void(*t_extcall)(t_stack&);
t_extcall external_calls[MAX_EXTERNAL_CALLS];
int numcallbacks = 0;
const unsigned char* vm_program = nullptr;
int vm_pc = 0;
int vm_cycles = 0;
t_stack vm_datastack;
t_stack vm_callstack;
void vm_init(const unsigned char* program) {
vm_program = program;
vm_pc = 0;
vm_datastack = stack_new(MAX_DATA_STACK);
vm_callstack = stack_new(MAX_CALL_STACK);
}
void vm_step() {
switch (vm_program[vm_pc++]) {
case OP_NOP: vm_cycles++; break;
case OP_PUSH: stack_push(vm_datastack, vm_program[vm_pc++]); vm_cycles++; break;
case OP_POP: stack_pop(vm_datastack); vm_cycles++; break;
case OP_DUP: stack_push(vm_datastack, stack_peek(vm_datastack)); vm_cycles++; break;
case OP_LOAD: vm_cycles++; break;
case OP_STORE: vm_cycles++; break;
case OP_JMP: vm_pc = vm_program[vm_pc] + (vm_program[vm_pc + 1] << 8); vm_cycles++; break;
case OP_JNT: vm_cycles++; break;
case OP_JTR: vm_cycles++; break;
case OP_JSR: vm_cycles++; break;
case OP_RET: vm_cycles++; break;
case OP_CALL: external_calls[vm_program[vm_pc++]](vm_datastack); vm_cycles++; break;
case OP_ADD: vm_cycles++; break;
case OP_SUB: vm_cycles++; break;
case OP_MUL: vm_cycles++; break;
case OP_DIV: vm_cycles++; break;
case OP_MOD: vm_cycles++; break;
case OP_AND: vm_cycles++; break;
case OP_OR: vm_cycles++; break;
case OP_NOT: vm_cycles++; break;
case OP_NEG: vm_cycles++; break;
case OP_INC: vm_cycles++; break;
case OP_EQ: vm_cycles++; break;
case OP_NEQ: vm_cycles++; break;
case OP_LT: vm_cycles++; break;
case OP_GT: vm_cycles++; break;
}
}
void vm_register_call(void(*callback)(t_stack&)) {
external_calls[numcallbacks++] = callback;
}