| 14 | namespace client |
| 15 | { |
| 16 | int vmachine::execute( |
| 17 | std::vector<int> const& code |
| 18 | , std::vector<int>::const_iterator pc |
| 19 | , std::vector<int>::iterator frame_ptr |
| 20 | ) |
| 21 | { |
| 22 | std::vector<int>::iterator stack_ptr = frame_ptr; |
| 23 | |
| 24 | while (true) |
| 25 | { |
| 26 | switch (*pc++) |
| 27 | { |
| 28 | case op_neg: |
| 29 | stack_ptr[-1] = -stack_ptr[-1]; |
| 30 | break; |
| 31 | |
| 32 | case op_not: |
| 33 | stack_ptr[-1] = !bool(stack_ptr[-1]); |
| 34 | break; |
| 35 | |
| 36 | case op_add: |
| 37 | --stack_ptr; |
| 38 | stack_ptr[-1] += stack_ptr[0]; |
| 39 | break; |
| 40 | |
| 41 | case op_sub: |
| 42 | --stack_ptr; |
| 43 | stack_ptr[-1] -= stack_ptr[0]; |
| 44 | break; |
| 45 | |
| 46 | case op_mul: |
| 47 | --stack_ptr; |
| 48 | stack_ptr[-1] *= stack_ptr[0]; |
| 49 | break; |
| 50 | |
| 51 | case op_div: |
| 52 | --stack_ptr; |
| 53 | stack_ptr[-1] /= stack_ptr[0]; |
| 54 | break; |
| 55 | |
| 56 | case op_eq: |
| 57 | --stack_ptr; |
| 58 | stack_ptr[-1] = bool(stack_ptr[-1] == stack_ptr[0]); |
| 59 | break; |
| 60 | |
| 61 | case op_neq: |
| 62 | --stack_ptr; |
| 63 | stack_ptr[-1] = bool(stack_ptr[-1] != stack_ptr[0]); |
| 64 | break; |
| 65 | |
| 66 | case op_lt: |
| 67 | --stack_ptr; |
| 68 | stack_ptr[-1] = bool(stack_ptr[-1] < stack_ptr[0]); |
| 69 | break; |
| 70 | |
| 71 | case op_lte: |
| 72 | --stack_ptr; |
| 73 | stack_ptr[-1] = bool(stack_ptr[-1] <= stack_ptr[0]); |