#include "vm.h"

u32 mp;           /* memory pointer */
u32 cp;           /* code pointer */
u32 pc;           /* program counter */
u32 flag;         /* flag */
u32 *code;        /* code */
u8 *mem;          /* memory */

bool step_vm() {

  u32 instruction = code[pc];
  u8 opcode = DECODE_OP(instruction);

  switch (opcode) {
  case OP_HALT: {
    return false;
  }
  case OP_CALL: {
      
  }
  case OP_RETURN: {
  }
  case OP_SYSCALL: {
  }
  case OP_LOAD_IMM: {
  }
  case OP_LOAD_UPPER_IMM: {
  }
  case OP_LOAD_IND_8: {
  }
  case OP_LOAD_IND_16: {
  }
  case OP_LOAD_IND_32: {
  }
  case OP_LOAD_ABS_8: {
  }
  case OP_LOAD_ABS_16: {
  }
  case OP_LOAD_ABS_32: {
  }
  case OP_LOAD_OFF_8: {
  }
  case OP_LOAD_OFF_16: {
  }
  case OP_LOAD_OFF_32: {
  }
  case OP_STORE_ABS_8: {
  }
  case OP_STORE_ABS_16: {
  }
  case OP_STORE_ABS_32: {
  }
  case OP_STORE_IND_8: {
  }
  case OP_STORE_IND_16: {
  }
  case OP_STORE_IND_32: {
  }
  case OP_STORE_OFF_8: {
  }
  case OP_STORE_OFF_16: {
  }
  case OP_STORE_OFF_32: {
  }
  case OP_MEM_ALLOC: {
  }
  case OP_MEM_CPY: {
  }
  case OP_MEM_SET_8: {
  }
  case OP_MEM_SET_16: {
  }
  case OP_MEM_SET_32: {
  }
  case OP_REG_MOV: {
  }
  case OP_ADD_INT: {
  }
  case OP_SUB_INT: {
  }
  case OP_MUL_INT: {
  }
  case OP_DIV_INT: {
  }
  case OP_ABS_INT: {
  }
  case OP_NEG_INT: {
  }
  case OP_ADD_NAT: {
  }
  case OP_SUB_NAT: {
  }
  case OP_MUL_NAT: {
  }
  case OP_DIV_NAT: {
  }
  case OP_ABS_NAT: {
  }
  case OP_NEG_NAT: {
  }
  case OP_ADD_REAL: {
  }
  case OP_SUB_REAL: {
  }
  case OP_MUL_REAL: {
  }
  case OP_DIV_REAL: {
  }
  case OP_ABS_REAL: {
  }
  case OP_NEG_REAL: {
  }
  case OP_INT_TO_REAL: {
  }
  case OP_INT_TO_NAT: {
  }
  case OP_NAT_TO_REAL: {
  }
  case OP_NAT_TO_INT: {
  }
  case OP_REAL_TO_INT: {
  }
  case OP_REAL_TO_NAT: {
  }
  case OP_BIT_SHIFT_LEFT: {
  }
  case OP_BIT_SHIFT_RIGHT: {
  }
  case OP_BIT_SHIFT_R_EXT: {
  }
  case OP_BIT_AND: {
  }
  case OP_BIT_OR: {
  }
  case OP_BIT_XOR: {
  }
  case OP_JMP_IMM: {
  }
  case OP_JMP_ABS: {
  }
  case OP_JMP_OFF: {
  }
  case OP_JMP_FLAG: {
  }
  case OP_JEQ_INT: {
  }
  case OP_JNE_INT: {
  }
  case OP_JGT_INT: {
  }
  case OP_JLT_INT: {
  }
  case OP_JLE_INT: {
  }
  case OP_JGE_INT: {
  }
  case OP_JEQ_NAT: {
  }
  case OP_JNE_NAT: {
  }
  case OP_JGT_NAT: {
  }
  case OP_JLT_NAT: {
  }
  case OP_JLE_NAT: {
  }
  case OP_JGE_NAT: {
  }
  case OP_JEQ_REAL: {
  }
  case OP_JNE_REAL: {
  }
  case OP_JGE_REAL: {
  }
  case OP_JGT_REAL: {
  }
  case OP_JLT_REAL: {
  }
  case OP_JLE_REAL: {
  }
  }

  /* something went very wrong */
  flag = 255;
  return false;
}