spirit/example/x3/calc/calc7/vm.cpp
2015-05-15 04:14:07 +08:00

51 lines
1.4 KiB
C++

/*=============================================================================
Copyright (c) 2001-2014 Joel de Guzman
Distributed under the Boost Software License, Version 1.0. (See accompanying
file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
=============================================================================*/
#include "vm.hpp"
namespace client
{
void vmachine::execute(std::vector<int> const& code)
{
std::vector<int>::const_iterator pc = code.begin();
stack_ptr = stack.begin();
while (pc != code.end())
{
switch (*pc++)
{
case op_neg:
stack_ptr[-1] = -stack_ptr[-1];
break;
case op_add:
--stack_ptr;
stack_ptr[-1] += stack_ptr[0];
break;
case op_sub:
--stack_ptr;
stack_ptr[-1] -= stack_ptr[0];
break;
case op_mul:
--stack_ptr;
stack_ptr[-1] *= stack_ptr[0];
break;
case op_div:
--stack_ptr;
stack_ptr[-1] /= stack_ptr[0];
break;
case op_int:
*stack_ptr++ = *pc++;
break;
}
}
}
}