example.cc

//
// This file is part of pug-vm.
// pug-vm is free software: you can redistribute it and/or modify it under the terms of the GNU
// General Public License as published by the Free Software Foundation, either version 3 of the
// License, or (at your option) any later version.
//
// pug-vm is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;  without
// even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License along with pug-vm. If not,
// see <http://www.gnu.org/licenses/>
//

#include "PugVM.hh"

int main () {

    using namespace PugVM;

    // Recursive faculty program.
    int res = 5;
    std::vector<Instruction> program {
        {LoadInt, &res}, // +1
        {Call, 5},
        {PopReduce},
        {StoreInt, &res},
        {Exit},

        // fac(x)
            {LoadArg, 0},
            {PushInt, 1},
            {NotEqualsII},
            {JumpRelIfTrue, 3},
                {PushInt, 1},
                {ReturnTos},

            {LoadArg,0},
            {DecrementI},
            {Call, 5},
            {PopReduce},
            {LoadArg,0},
            {MulII},
            {ReturnTos}
    };

    /*
    // Iterative faculty program.
    std::vector<Instruction> program{
        {LoadInt, &res},  // [local 0]
        {Dup},            // [local 1] duplicate input to be used as counter

        // start of while loop
        {Dup},              // \
        {PushInt,1},        // | compare counter to 1
        {EqualsII},         // /      \
        {JumpRelIfTrue, 7}, //      quit if counter is 1

        {DecrementI},

        {LoadLocal, 0},
        {LoadLocal, 1},
        {MulII},
        {StoreLocal, 0},
        {Jump, 2},
        // loop end

        {Pop},
        {StoreInt, &res},
        {Exit}
    };*/



    PugVM::StackMachine<true> m(program);
    while (!m.halted()) {
        m.tick();
    }
    std::cout << "res: " << res << std::endl;
}