2018-05-21 20:55:48 +00:00
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'use strict';
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2018-05-21 21:18:05 +00:00
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// ------------------------------------------------------------------
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// Definitions
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// ------------------------------------------------------------------
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2018-05-21 20:55:48 +00:00
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// Use symbols for the names of the instructions
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// Unsure if this helps in any way over strings, but I feel it neater
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// +++++ → {type: add, value: 5}
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2018-05-22 12:08:23 +00:00
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// Can have offset property
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2018-05-21 20:55:48 +00:00
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const add = Symbol('add');
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// > → {type: moveHead, value: 1}
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const moveHead = Symbol('moveHead');
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// . → {type: writeByte}
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2018-05-22 12:08:23 +00:00
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// Can have offset property
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2018-05-21 20:55:48 +00:00
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const writeByte = Symbol('writeByte');
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// , → {type: readByte}
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2018-05-22 12:08:23 +00:00
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// Can have offset property
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2018-05-21 20:55:48 +00:00
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const readByte = Symbol('readByte');
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// [-] → {type: loop, contents: [{type: add, value: -1}]}
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2018-05-22 12:08:23 +00:00
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// Can have isBalanced property
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2018-05-21 20:55:48 +00:00
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const loop = Symbol('loop');
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2018-05-22 11:26:40 +00:00
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// [-] → {type: clear}
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2018-05-22 12:08:23 +00:00
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// Can have offset property
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2018-05-22 11:26:40 +00:00
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const clear = Symbol('clear');
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2018-05-23 18:48:21 +00:00
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// {type: jumpIfZero, target: 5}
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const jumpIfZero = Symbol('jumpIfZero');
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// {type: jumpIfNonZero, target: 2}
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const jumpIfNonZero = Symbol('jumpIfNonZero');
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2018-05-21 20:55:48 +00:00
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// TODO: Add extensions from Eldis
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2018-05-23 21:11:25 +00:00
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class ParsingError extends Error {}
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class UnknownIRError extends Error {}
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2018-05-21 21:18:05 +00:00
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// ------------------------------------------------------------------
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// Parsing
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// ------------------------------------------------------------------
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2018-05-21 20:55:48 +00:00
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// (string) → [commandObjects]
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2018-05-23 18:57:07 +00:00
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// May throw ParsingError
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2018-05-21 20:55:48 +00:00
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function parse(program) {
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// (string, int, bool) → {parsed: [commandObjects], lastIndex: int}
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// index is the index of the next character to consume
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// inLoop tells whether we're parsing a loop or the top level
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// lastIndex is the last index the function consumed
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function constructTree(program, index = 0, inLoop = false) {
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let commands = [];
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// Move this out of the loop body since we need to return
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// the index of the last character we parsed
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let i = index;
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for(;;) {
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if(i >= program.length) {
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// If we're parsing a loop, we have a
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// missing ]
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// If we're parsing the top level, this is
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// where we should exit
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if(inLoop) {
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throw new ParsingError('Missing ]');
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} else {
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break;
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}
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i++;
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} else if(program[i] == ']') {
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// If we're parsing a loop, this is where we
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// should exit
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// If we're parsing the top level, we have a
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// missing [
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if(inLoop) {
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break;
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} else {
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throw new ParsingError('Missing [');
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}
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i++;
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} else if(program[i] == '+' || program[i] == '-') {
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// Fold a run of +s and -s into one node
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let value = 0;
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for(; i < program.length; i++) {
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if(program[i] == '+') {
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value++;
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} else if(program[i] == '-') {
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value--;
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} else {
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// Reached end of the run
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break;
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}
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}
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2018-05-22 11:26:40 +00:00
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// Only add the command is value is not 0
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if(value != 0) {
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commands.push({type: add, value: value});
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}
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2018-05-21 20:55:48 +00:00
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// i is not incremented, since it already
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// points to a location containig a char we
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// have not yet handled
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} else if(program[i] == '<' || program[i] == '>') {
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// Fold a run of <s and >s into one node
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let value = 0;
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for(; i < program.length; i++) {
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if(program[i] == '>') {
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value++;
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} else if(program[i] == '<') {
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value--;
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} else {
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// Reached end of the run
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break;
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}
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}
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2018-05-22 11:26:40 +00:00
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// Only add the command is value is not 0
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if(value != 0) {
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commands.push({type: moveHead, value: value});
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}
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2018-05-21 20:55:48 +00:00
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// see +/- for why we don't increment i
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} else if(program[i] == '.') {
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commands.push({type: writeByte});
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i++;
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} else if(program[i] == ',') {
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commands.push({type: readByte});
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i++;
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} else if(program[i] == '[') {
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// Parse a loop. This is done by calling the
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// same parser function recursively
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// Due to this the loop appears as one node
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// in the parsed result
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let {parsed, lastIndex} = constructTree(
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program, // Same program data
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i + 1, // Start at the next char
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true // We're parsing a loop
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);
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commands.push({type: loop, contents: parsed});
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// Since lastIndex was consumed by the inner
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// function, we don't want to consume it a
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// second time
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i = lastIndex + 1;
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} else {
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// All others characters are comments,
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// ignore them
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i++;
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}
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}
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return {parsed: commands, lastIndex: i};
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}
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// We only care about the parsed contents, since under normal
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// operarion we only get out of the loop if we've reached the end
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// of the program
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let {parsed} = constructTree(program);
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return parsed;
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}
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2018-05-23 18:57:07 +00:00
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// ([commandObjects/offsetCommandObjects]) → str
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function prettifyIR(parsed) {
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// ([commandObjects/offsetCommandObjects], string) → str
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function worker(parsed, indent = '') {
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let lines = [];
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2018-05-23 18:48:21 +00:00
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for(let i = 0; i < parsed.length; i++) {
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let command = parsed[i];
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let line = `${indent}${i} `;
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2018-05-21 20:55:48 +00:00
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if(command.type == add) {
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line += `add ${command.value}`;
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2018-05-22 12:08:23 +00:00
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if('offset' in command) {
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line += ` (${command.offset})`;
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}
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2018-05-23 18:57:07 +00:00
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lines.push(line);
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2018-05-21 20:55:48 +00:00
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} else if(command.type == moveHead) {
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line += `moveHead ${command.value}`;
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2018-05-23 18:57:07 +00:00
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lines.push(line);
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2018-05-21 20:55:48 +00:00
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} else if(command.type == writeByte) {
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line += 'writeByte';
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2018-05-22 12:08:23 +00:00
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if('offset' in command) {
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line += ` (${command.offset})`;
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}
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2018-05-23 18:57:07 +00:00
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lines.push(line);
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2018-05-21 20:55:48 +00:00
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} else if(command.type == readByte) {
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line += 'readByte';
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2018-05-22 12:08:23 +00:00
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if('offset' in command) {
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line += ` (${command.offset})`;
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}
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2018-05-23 18:57:07 +00:00
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lines.push(line);
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2018-05-21 20:55:48 +00:00
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} else if(command.type == loop) {
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line += 'loop';
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2018-05-22 12:08:23 +00:00
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if('isBalanced' in command) {
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line += ` (balanced: ${command.isBalanced})`;
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}
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2018-05-23 18:57:07 +00:00
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lines.push(line);
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lines = lines.concat(worker(command.contents, indent + ' '));
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2018-05-22 11:26:40 +00:00
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} else if(command.type == clear) {
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line += 'clear';
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2018-05-22 12:08:23 +00:00
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if('offset' in command) {
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line += ` (${command.offset})`;
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}
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2018-05-23 18:57:07 +00:00
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lines.push(line);
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2018-05-23 18:48:21 +00:00
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} else if(command.type == jumpIfZero) {
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line += `jumpIfZero ${command.target}`;
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2018-05-23 18:57:07 +00:00
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lines.push(line);
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2018-05-23 18:48:21 +00:00
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} else if(command.type == jumpIfNonZero) {
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line += `jumpIfNonZero ${command.target}`;
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2018-05-23 18:57:07 +00:00
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lines.push(line);
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2018-05-21 20:55:48 +00:00
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} else {
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line += `unknown ${command.type}`;
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2018-05-23 18:57:07 +00:00
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lines.push(line);
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2018-05-21 20:55:48 +00:00
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}
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}
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2018-05-23 18:57:07 +00:00
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2018-05-24 20:05:59 +00:00
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return lines
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2018-05-21 20:55:48 +00:00
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}
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2018-05-24 20:05:59 +00:00
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return worker(parsed).join('\n');
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2018-05-21 20:55:48 +00:00
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}
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2018-05-21 21:18:05 +00:00
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// ------------------------------------------------------------------
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// Optimization passes
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// ------------------------------------------------------------------
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// ([commandObjects]) → [commandObjects]
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function joinAdjacentOps(parsed) {
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// ([commandObjects], commandType) → [commandObjects]
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function worker(parsed, type) {
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let optimized = [];
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let prevOfType = false, value = 0;
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for(let command of parsed) {
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if(prevOfType && command.type == type) {
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// Update value, don't add to optimized yet
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value += command.value;
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} else if(!prevOfType && command.type == type) {
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// Start of a possible run of commands
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prevOfType = true;
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value = command.value;
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2018-05-24 19:50:31 +00:00
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} else {
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// If a run has ended, add it to optimized
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2018-05-21 21:18:05 +00:00
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// However, skip it if value is 0
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2018-05-24 19:50:31 +00:00
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if(prevOfType && value != 0) {
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2018-05-21 21:18:05 +00:00
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optimized.push({type: type, value: value});
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}
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2018-05-24 19:50:31 +00:00
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// Add the command for this round
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if(command.type == loop) {
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// Recurse
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optimized.push({type: loop,
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contents: worker(
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command.contents,
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type)});
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} else {
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optimized.push(command);
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}
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2018-05-21 21:18:05 +00:00
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prevOfType = false;
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}
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}
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// Did we end with a command of given type
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if(prevOfType) {
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// Yes, add it to optimized (unless value is 0)
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if(value != 0) {
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optimized.push({type: type, value: value});
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}
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}
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return optimized;
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}
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return worker(worker(parsed, moveHead), add);
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}
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2018-05-22 11:26:40 +00:00
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// ([commandObjects]) → [commandObjects]
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function transformClearLoops(parsed) {
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let optimized = [];
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for(let command of parsed) {
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// Only match loops like [-] or [+]
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let isClearLoop = command.type == loop &&
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command.contents.length == 1 &&
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command.contents[0].type == add &&
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(command.contents[0].value == 1 ||
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command.contents[0].value == -1);
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if(isClearLoop) {
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optimized.push({type: clear});
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} else if(command.type == loop) {
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// Run for inner loops
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optimized.push({type: loop,
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contents: transformClearLoops(command.contents)});
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} else {
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optimized.push(command);
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}
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}
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return optimized;
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}
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2018-05-22 12:08:23 +00:00
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// ([commandObjects]) → [offsetCommandObjects]
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function addOffsetProperties(parsed) {
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// ([commandObjects]) → {offsetted: [offsetCommandObjects], isBalanced: bool}
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function worker(parsed) {
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let offsetted = [];
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let isBalanced = true;
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let headChange = 0;
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let offset = 0;
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for(let command of parsed) {
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if(command.type == add) {
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offsetted.push({type: add,
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value: command.value,
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offset: offset});
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} else if(command.type == moveHead) {
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offset += command.value;
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} else if(command.type == writeByte) {
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offsetted.push({type: writeByte,
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offset: offset});
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} else if(command.type == readByte) {
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offsetted.push({type: readByte,
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offset: offset});
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} else if(command.type == clear) {
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offsetted.push({type: clear,
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offset: offset});
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} else if(command.type == loop) {
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// A loop should be self-contained
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// If offset is not 0, add a moveHead
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if(offset != 0) {
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offsetted.push({type: moveHead,
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value: offset});
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// Mark we've moved the head
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headChange += offset;
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}
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offset = 0;
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// Run optimization on the loop
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let result = worker(command.contents);
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// We're only balanced if our loops are
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isBalanced = isBalanced && result.isBalanced;
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offsetted.push({type: loop,
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contents: result.offsetted,
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isBalanced: result.isBalanced});
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// headChange's value becomes invalid if the
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// loop is not balanced. However, we only
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// care about its value when figuring out
|
|
|
|
// our isBalanced, which will be forced to
|
|
|
|
// false if any inner loop is not balanced
|
|
|
|
} else {
|
|
|
|
throw new UnknownIRError();
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
// We need to move the tape head in the end anyways, so
|
|
|
|
// generate moveHead is offseet is not 0
|
|
|
|
if(offset != 0) {
|
|
|
|
offsetted.push({type: moveHead,
|
|
|
|
value: offset});
|
|
|
|
}
|
|
|
|
|
|
|
|
// We're only balanced if relative to start of the loop ends
|
|
|
|
// up as 0
|
|
|
|
isBalanced = isBalanced && offset + headChange == 0;
|
|
|
|
|
|
|
|
return {offsetted, isBalanced};
|
|
|
|
}
|
|
|
|
|
|
|
|
return worker(parsed).offsetted;
|
|
|
|
}
|
|
|
|
|
2018-05-22 12:10:10 +00:00
|
|
|
// TODO: Optimization pass to turn copy loops into copy commands
|
|
|
|
|
2018-05-23 18:48:21 +00:00
|
|
|
// ([offsetCommandObjects]) → [flatCommandObjects]
|
|
|
|
function flattenLoops(offsetted) {
|
|
|
|
// ([offsetCommandObjects], int) → [flatCommandObjects]
|
|
|
|
// prevLength tells length of the flattened program up until now
|
|
|
|
function worker(offsetted, prevLength = 0) {
|
|
|
|
let flattened = [];
|
|
|
|
|
|
|
|
for(let command of offsetted) {
|
|
|
|
if(command.type == loop) {
|
|
|
|
// flattened.length is the index of the next
|
|
|
|
// command in out flattened
|
|
|
|
// flattened.length + prevLength is the
|
|
|
|
// index of it in the resulting combined
|
|
|
|
// flattened
|
|
|
|
// Since this should be the index of the
|
|
|
|
// start of the loop body we want to point
|
|
|
|
// after the next command, which is going
|
|
|
|
// to be the jump
|
|
|
|
let startIndex = flattened.length +
|
|
|
|
prevLength + 1;
|
|
|
|
|
|
|
|
let loopBody = worker(command.contents,
|
|
|
|
startIndex // length = index of next
|
|
|
|
);
|
|
|
|
|
|
|
|
// startIndex + loopBody.length is the index
|
|
|
|
// of the next command after the loop body
|
|
|
|
// The command after it is going to be the
|
|
|
|
// jump back to the start of the body, so we
|
|
|
|
// want to point to the command after it
|
|
|
|
let endIndex = startIndex +
|
|
|
|
loopBody.length + 1;
|
|
|
|
|
|
|
|
// Add the first jump
|
|
|
|
flattened.push({type: jumpIfZero,
|
|
|
|
target: endIndex});
|
|
|
|
|
|
|
|
// Add the loop body
|
|
|
|
flattened = flattened.concat(loopBody);
|
|
|
|
|
|
|
|
// Add the second loop
|
|
|
|
flattened.push({type: jumpIfNonZero,
|
|
|
|
target: startIndex});
|
|
|
|
} else {
|
|
|
|
flattened.push(command);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
return flattened;
|
|
|
|
}
|
|
|
|
|
|
|
|
return worker(offsetted);
|
|
|
|
}
|
|
|
|
|
2018-05-23 21:11:25 +00:00
|
|
|
// ([commandObjects]) → [flatCommandObjects]
|
2018-05-21 21:18:05 +00:00
|
|
|
function optimize(parsed) {
|
2018-05-22 12:08:23 +00:00
|
|
|
const optimizations = [
|
|
|
|
joinAdjacentOps,
|
|
|
|
transformClearLoops,
|
2018-05-23 18:48:21 +00:00
|
|
|
addOffsetProperties,
|
|
|
|
flattenLoops
|
2018-05-22 12:08:23 +00:00
|
|
|
]
|
2018-05-22 11:26:40 +00:00
|
|
|
return optimizations.reduce((IR, optimization) =>
|
|
|
|
optimization(IR), parsed);
|
2018-05-21 21:18:05 +00:00
|
|
|
}
|
2018-05-22 12:10:10 +00:00
|
|
|
|
|
|
|
// ------------------------------------------------------------------
|
|
|
|
// Virtual machine
|
|
|
|
// ------------------------------------------------------------------
|
|
|
|
|
2018-05-25 11:19:09 +00:00
|
|
|
// ([flatCommandObject], [int]) → girVMState
|
2018-05-23 21:11:25 +00:00
|
|
|
function newVM(program, input) {
|
|
|
|
return {
|
|
|
|
// Initial state for the machine
|
|
|
|
program: program,
|
|
|
|
ip: 0,
|
|
|
|
|
|
|
|
memory: Object.create(null),
|
|
|
|
tapeHead: 0,
|
|
|
|
|
|
|
|
input: input,
|
2018-05-25 11:19:09 +00:00
|
|
|
output: []
|
2018-05-23 21:11:25 +00:00
|
|
|
};
|
|
|
|
}
|
|
|
|
|
2018-05-24 20:20:52 +00:00
|
|
|
// (girVMState, int) → {state: girVMState, complete: bool, cycles: int}
|
|
|
|
// complete is set to true is the program completed its execution
|
|
|
|
// cycles is the number of cycles the VM ran
|
2018-05-23 21:11:25 +00:00
|
|
|
// If maxCycles is null, the program runs until completion
|
|
|
|
function runVM(state, maxCycles = null) {
|
|
|
|
let program = state.program;
|
|
|
|
let ip = state.ip;
|
|
|
|
|
|
|
|
// Create a copy of the memory, since we're going to modify it
|
|
|
|
// TODO: Make memory into a Proxied thing that returns 0 if it
|
|
|
|
// doesn't have the requested cell
|
|
|
|
let memory = Object.create(null);
|
|
|
|
for(let key in state.memory) {
|
|
|
|
memory[key] = state.memory[key];
|
|
|
|
}
|
|
|
|
let tapeHead = state.tapeHead;
|
|
|
|
|
2018-05-25 11:19:09 +00:00
|
|
|
// Create copies of input and output, since we might modify them
|
|
|
|
let input = state.input.slice();
|
|
|
|
let output = state.output.slice();
|
2018-05-23 21:11:25 +00:00
|
|
|
|
2018-05-24 20:20:52 +00:00
|
|
|
let complete = false;
|
|
|
|
let cycle = 0;
|
|
|
|
for(; maxCycles === null || cycle < maxCycles; cycle++) {
|
2018-05-23 21:11:25 +00:00
|
|
|
// Exit the loop if we run to the end of the program
|
|
|
|
if(ip >= program.length) {
|
2018-05-24 20:20:52 +00:00
|
|
|
// Program completed
|
|
|
|
complete = true;
|
2018-05-23 21:11:25 +00:00
|
|
|
break;
|
|
|
|
}
|
|
|
|
|
|
|
|
let command = program[ip];
|
|
|
|
|
|
|
|
// See if we need to make sure the cell we're on exists and
|
|
|
|
// calculate the index into the array of the cell we're
|
|
|
|
// accessing
|
|
|
|
let index = tapeHead;
|
|
|
|
switch(command.type) {
|
|
|
|
case add:
|
|
|
|
case writeByte:
|
|
|
|
case readByte:
|
|
|
|
case clear:
|
|
|
|
// These have an offset property, add it
|
|
|
|
index += command.offset;
|
|
|
|
// Fall through
|
|
|
|
case jumpIfZero:
|
|
|
|
case jumpIfNonZero:
|
|
|
|
// Ensure the cell exists
|
|
|
|
if(!(index in memory)) {
|
|
|
|
memory[index] = 0;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
// Run the command
|
|
|
|
switch(command.type) {
|
|
|
|
case add:
|
|
|
|
if(!(index in memory)) memory[index] = 0;
|
|
|
|
memory[index] += command.value;
|
|
|
|
// Implement wraparound
|
|
|
|
memory[index] = memory[index] & 0xFF;
|
|
|
|
ip++;
|
|
|
|
break;
|
|
|
|
|
|
|
|
case moveHead:
|
|
|
|
tapeHead += command.value;
|
|
|
|
ip++;
|
|
|
|
break;
|
|
|
|
|
|
|
|
case writeByte:
|
|
|
|
if(!(index in memory)) memory[index] = 0;
|
2018-05-25 11:19:09 +00:00
|
|
|
output.push(memory[index]);
|
2018-05-23 21:11:25 +00:00
|
|
|
ip++;
|
|
|
|
break;
|
|
|
|
|
|
|
|
case readByte:
|
|
|
|
// Have we reached EOF?
|
|
|
|
if(input.length == 0) {
|
|
|
|
// Yes, return 0
|
|
|
|
memory[index] = 0;
|
|
|
|
} else {
|
|
|
|
// No, return character
|
2018-05-25 11:19:09 +00:00
|
|
|
memory[index] = input.shift();
|
2018-05-23 21:11:25 +00:00
|
|
|
}
|
|
|
|
ip++;
|
|
|
|
break;
|
|
|
|
|
|
|
|
case clear:
|
|
|
|
memory[index] = 0;
|
|
|
|
ip++;
|
|
|
|
break;
|
|
|
|
|
|
|
|
case jumpIfZero:
|
|
|
|
if(!(index in memory)) memory[index] = 0;
|
|
|
|
if(memory[index] == 0) {
|
|
|
|
ip = command.target;
|
|
|
|
} else {
|
|
|
|
ip++;
|
|
|
|
}
|
|
|
|
break;
|
|
|
|
|
|
|
|
case jumpIfNonZero:
|
|
|
|
if(!(index in memory)) memory[index] = 0;
|
|
|
|
if(memory[index] != 0) {
|
|
|
|
ip = command.target;
|
|
|
|
} else {
|
|
|
|
ip++;
|
|
|
|
}
|
|
|
|
break;
|
|
|
|
|
|
|
|
default:
|
|
|
|
// Unknown command type
|
|
|
|
throw new UnknownIRError();
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
let newState = {
|
|
|
|
program,
|
|
|
|
ip,
|
|
|
|
|
|
|
|
memory,
|
|
|
|
tapeHead,
|
|
|
|
|
|
|
|
input,
|
|
|
|
output
|
|
|
|
};
|
|
|
|
|
2018-05-24 20:20:52 +00:00
|
|
|
return {state: newState, complete: complete, cycles: cycle};
|
2018-05-23 21:11:25 +00:00
|
|
|
}
|
|
|
|
|
2018-05-25 11:19:09 +00:00
|
|
|
// ------------------------------------------------------------------
|
|
|
|
// UTF-8
|
|
|
|
// ------------------------------------------------------------------
|
|
|
|
|
|
|
|
// string → [int]
|
|
|
|
function encodeUTF8(string) {
|
|
|
|
let encoded = [];
|
|
|
|
|
|
|
|
for(let character of string) {
|
|
|
|
let codepoint = character.codePointAt(0);
|
|
|
|
|
|
|
|
if(codepoint < 0x80) {
|
|
|
|
// 0xxxxxxx
|
|
|
|
encoded.push(codepoint);
|
|
|
|
} else if(codepoint < 0x0800) {
|
|
|
|
// 110xxxxx 10xxxxxx
|
|
|
|
let b1 = codepoint >> 6 | 0b11000000;
|
|
|
|
let b2 = codepoint & 0b00111111 | 0b10000000;
|
|
|
|
encoded.push(b1);
|
|
|
|
encoded.push(b2);
|
|
|
|
} else if(codepoint < 0x10000) {
|
|
|
|
// 1110xxxx 10xxxxxx 10xxxxxx
|
|
|
|
let b1 = codepoint >> 12 | 0b11100000;
|
|
|
|
let b2 = codepoint >> 6 & 0b00111111 | 0b10000000;
|
|
|
|
let b3 = codepoint & 0b00111111 | 0b10000000;
|
|
|
|
encoded.push(b1);
|
|
|
|
encoded.push(b2);
|
|
|
|
encoded.push(b3);
|
|
|
|
} else {
|
|
|
|
// 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
|
|
|
|
let b1 = codepoint >> 18 | 0b11110000;
|
|
|
|
let b2 = codepoint >> 12 & 0b00111111 | 0b10000000;
|
|
|
|
let b3 = codepoint >> 6 & 0b00111111 | 0b10000000;
|
|
|
|
let b4 = codepoint & 0b00111111 | 0b10000000;
|
|
|
|
encoded.push(b1);
|
|
|
|
encoded.push(b2);
|
|
|
|
encoded.push(b3);
|
|
|
|
encoded.push(b4);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
return encoded;
|
|
|
|
}
|
|
|
|
|
|
|
|
// [int] → string
|
|
|
|
function decodeUTF8(encoded) {
|
|
|
|
let codePoints = [];
|
|
|
|
|
|
|
|
for(let i = 0; i < encoded.length;) {
|
|
|
|
let codePoint = 0;
|
|
|
|
|
|
|
|
let firstByte = encoded[i];
|
|
|
|
i++;
|
|
|
|
|
|
|
|
let toRead = null;
|
|
|
|
// Determine number of continuation bytes to read and
|
|
|
|
// decode the first byte into codePoint
|
|
|
|
// Since we'll do the shifts later, we just mask here
|
|
|
|
if(firstByte >> 7 == 0) {
|
|
|
|
// 0xxxxxxx
|
|
|
|
toRead = 0;
|
|
|
|
codePoint = firstByte;
|
|
|
|
} else if(firstByte >> 5 == 0b110) {
|
|
|
|
// 110xxxxx 10xxxxxx
|
|
|
|
toRead = 1;
|
|
|
|
codePoint = firstByte & 0b00011111;
|
|
|
|
} else if(firstByte >> 4 == 0b1110) {
|
|
|
|
// 1110xxxx 10xxxxxx 10xxxxxx
|
|
|
|
toRead = 2;
|
|
|
|
codePoint = firstByte & 0b00001111;
|
|
|
|
} else if(firstByte >> 3 == 0b11110) {
|
|
|
|
// 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
|
|
|
|
toRead = 3;
|
|
|
|
codePoint = firstByte & 0b00000111;
|
|
|
|
} else {
|
|
|
|
// Illegal sequence, push replacement char
|
|
|
|
codePoints.push(0xFFFD);
|
|
|
|
continue;
|
|
|
|
}
|
|
|
|
|
|
|
|
for(; toRead > 0 && i < encoded.length; toRead--) {
|
|
|
|
let continuationByte = encoded[i];
|
|
|
|
i++;
|
|
|
|
|
|
|
|
// Check that we have a valid continuation byte
|
|
|
|
if(continuationByte >> 6 == 0b10) {
|
|
|
|
// We do, add its contents to codePoint
|
|
|
|
codePoint = codePoint << 6 |
|
|
|
|
continuationByte & 0b00111111;
|
|
|
|
} else {
|
|
|
|
// We don't, break out of the loop
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
// Did we read all required continuation bytes?
|
|
|
|
if(toRead == 0) {
|
|
|
|
// We did, add the codepoint to the array
|
|
|
|
codePoints.push(codePoint);
|
|
|
|
} else {
|
|
|
|
// We didn't, push replacement char
|
|
|
|
codePoints.push(0xFFFD);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
// Convert to a string
|
|
|
|
let decoded = codePoints.map(x => String.fromCodePoint(x)).join('');
|
|
|
|
|
|
|
|
return decoded;
|
|
|
|
}
|
|
|
|
|
2018-05-23 21:11:25 +00:00
|
|
|
// ------------------------------------------------------------------
|
|
|
|
// User-facing functions
|
|
|
|
// ------------------------------------------------------------------
|
|
|
|
|
|
|
|
// (string) → [flatCommandObjects]
|
|
|
|
function compile(program) {
|
|
|
|
return optimize(parse(program));
|
|
|
|
}
|
|
|
|
|
2018-05-25 11:19:09 +00:00
|
|
|
// (string, string, int) → string
|
2018-05-24 20:36:24 +00:00
|
|
|
function run(program, input, maxCycles = null) {
|
2018-05-23 21:11:25 +00:00
|
|
|
// TODO; Cache programs
|
|
|
|
let compiled = compile(program);
|
2018-05-25 11:19:09 +00:00
|
|
|
let vm = newVM(compiled, encodeUTF8(input));
|
2018-05-24 20:36:24 +00:00
|
|
|
|
|
|
|
let result = runVM(vm, maxCycles);
|
2018-05-25 11:19:09 +00:00
|
|
|
let output = decodeUTF8(result.state.output);
|
2018-05-24 20:36:24 +00:00
|
|
|
|
|
|
|
// If didn't complete, mark it in the output
|
|
|
|
if(!result.complete) {
|
|
|
|
output += '«TLE»';
|
|
|
|
}
|
|
|
|
|
|
|
|
return output;
|
2018-05-23 21:11:25 +00:00
|
|
|
}
|