You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
97 lines
2.2 KiB
C++
97 lines
2.2 KiB
C++
/**
|
|
* Alee Forth: A portable and concise Forth implementation in modern C++.
|
|
* Copyright (C) 2023 Clyne Sullivan <clyne@bitgloo.com>
|
|
*
|
|
* This program is free software: you can redistribute it and/or modify
|
|
* it under the terms of the GNU Lesser General Public License as published by
|
|
* the Free Software Foundation, either version 3 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This program 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 Lesser General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Lesser General Public License
|
|
* along with this program. If not, see <https://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
#ifndef ALEEFORTH_STATE_HPP
|
|
#define ALEEFORTH_STATE_HPP
|
|
|
|
#include "dictionary.hpp"
|
|
#include "types.hpp"
|
|
|
|
#include <cstddef>
|
|
#include <iterator>
|
|
|
|
constexpr unsigned DataStackSize = 12;
|
|
constexpr unsigned ReturnStackSize = 12;
|
|
|
|
class State
|
|
{
|
|
Cell dstack[DataStackSize] = {};
|
|
Cell rstack[ReturnStackSize] = {};
|
|
Cell *dsp = dstack - 1;
|
|
Cell *rsp = rstack - 1;
|
|
|
|
public:
|
|
bool compiling = false;
|
|
Addr ip = 0;
|
|
Pass pass = Pass::None;
|
|
Dictionary& dict;
|
|
|
|
constexpr State(Dictionary& d): dict(d) {}
|
|
|
|
Cell beyondip() const {
|
|
return dict.read(ip + 1);
|
|
}
|
|
|
|
void pushr(Cell value) {
|
|
if (rsize() == ReturnStackSize)
|
|
throw;
|
|
*++rsp = value;
|
|
}
|
|
|
|
Cell popr() {
|
|
if (rsize() == 0)
|
|
throw;
|
|
return *rsp--;
|
|
}
|
|
|
|
void push(Cell value) {
|
|
if (size() == DataStackSize)
|
|
throw;
|
|
*++dsp = value;
|
|
}
|
|
|
|
Cell pop() {
|
|
if (size() == 0)
|
|
throw;
|
|
return *dsp--;
|
|
}
|
|
|
|
Cell& top() {
|
|
if (size() == 0)
|
|
throw;
|
|
return *dsp;
|
|
}
|
|
|
|
Cell& pick(std::size_t i) {
|
|
if (i >= size())
|
|
throw;
|
|
return *(dsp - i);
|
|
}
|
|
|
|
std::size_t size() const noexcept {
|
|
return std::distance(dstack, static_cast<const Cell *>(dsp)) + 1;
|
|
}
|
|
|
|
std::size_t rsize() const noexcept {
|
|
return std::distance(rstack, static_cast<const Cell *>(rsp)) + 1;
|
|
}
|
|
};
|
|
|
|
#endif // ALEEFORTH_STATE_HPP
|
|
|