asm.js

import charInfoJP from '../../data/charInfo-JP.json';
import charInfoEU from '../../data/charInfo-EU.json';
import charInfoUS from '../../data/charInfo-US.json';

/**
 * @typedef {number} Inst
 *
 * @typedef {(
 *   rT: number,
 *   rA: number,
 *   D: number,
 * ) => Inst} InstD
 * @typedef {(
 *   rS: number,
 *   rA: number,
 *   D: number,
 * ) => Inst} InstDS
 *
 * @typedef {(
 *   rA: number,
 *   rS: number,
 *   SH: number,
 *   MB: number,
 *   ME: number,
 *   Rc: number|boolean,
 * ) => Inst} InstM
 *
 * @typedef {(
 *   rT: number,
 *   rA: number,
 *   rB: number,
 *   Rc?: number|boolean,
 * ) => Inst} InstX
 * @typedef {(
 *   rS: number,
 *   rA: number,
 *   rB: number,
 *   Rc: number|boolean,
 * ) => Inst} InstXS
 *
 * @typedef {(
 *   LL: number,
 *   LK: number|boolean,
 *   AA?: number|boolean,
 * ) => Inst} InstI
 */

/**
 * @param {number} op
 * @param {number} rT
 * @param {number} rA
 * @param {number} D
 */
const InstD = (op, rT, rA, D) =>
  ((op & 0x3f) << 26) | ((rT & 0x1f) << 21) | ((rA & 0x1f) << 16) | (D & 0xffff);
/**
 * @param {number} op
 * @param {number} rT
 * @param {number} rA
 * @param {number} rB
 * @param {number} op2
 * @param {number} Rc
 */
const InstX = (op, rT, rA, rB, op2, Rc) =>
  ((op & 0x3f) << 26) |
  ((rT & 0x1f) << 21) |
  ((rA & 0x1f) << 16) |
  ((rB & 0x1f) << 11) |
  ((op2 & 0x3ff) << 1) |
  Rc;
/**
 * @param {number} op
 * @param {number} RS
 * @param {number} RA
 * @param {number} SH
 * @param {number} MB
 * @param {number} ME
 * @param {number} Rc
 */
const InstM = (op, RA, RS, SH, MB, ME, Rc) =>
  ((op & 0x3f) << 26) |
  ((RS & 0x1f) << 21) |
  ((RA & 0x1f) << 16) |
  ((SH & 0x1f) << 11) |
  ((MB & 0x1f) << 6) |
  ((ME & 0x1f) << 1) |
  Rc;
/**
 * @param {number} op
 * @param {number} LL
 * @param {number} AA
 * @param {number} LK
 */
const InstI = (op, LL, AA, LK) =>
  ((op & 0x3f) << 26) | ((LL & 0xffffff) << 2) | ((AA & 1) << 1) | (LK & 1);

/** @type {(op: number) => InstD} */
const makeInstD = (op) => (rT, rA, D) => InstD(op, rT, rA, D);
/** @type {(op: number) => InstDS} */
const makeInstDS = (op) => (rA, rS, D) => InstD(op, rA, rS, D);
/** @type {(op: number, op2: number) => InstX} */
const makeInstX =
  (op, op2) =>
  (rT, rA, rB, Rc = 0) =>
    InstX(op, rT, rA, rB, op2, +Rc);
/** @type {(op: number, op2: number) => InstXS} */
const makeInstXS = (op, op2) => (rA, rS, rB, Rc) => InstX(op, rA, rS, rB, op2, +Rc);
/** @type {(op: number) => InstM} */
const makeInstM = (op) => (rA, rS, SH, MB, ME, Rc) => InstM(op, rA, rS, SH, MB, ME, +Rc);
/** @type {(op: number) => InstI} */
const makeInstI =
  (op) =>
  (LL, LK, AA = 0) =>
    InstI(op, LL >> 2, +AA, +LK);

export const ASM = {
  // store rT, rA, D
  stb: makeInstD(38),
  sth: makeInstD(44),
  stw: makeInstD(36),
  stfs: makeInstD(52),
  stfd: makeInstD(54),
  stwu: makeInstD(37),
  // load rS, rA, D
  lbz: makeInstD(34),
  lhz: makeInstD(40),
  lha: makeInstD(42),
  lwz: makeInstD(32),
  lfs: makeInstD(48),
  lfd: makeInstD(50),
  // add
  add: makeInstX(31, 266),
  // li rT, D
  addi: makeInstD(14),
  li: (/**@type{number}*/ rT, /**@type{number}*/ D) => InstD(14, rT, 0, D),
  addis: makeInstD(15),
  lis: (/**@type{number}*/ rT, /**@type{number}*/ D) => InstD(15, rT, 0, D),
  // ori rA, rS, D
  ori: makeInstDS(24),
  // or rA, rS, rB, flag
  or: makeInstXS(31, 444),
  mr: (/**@type{number}*/ rT, /**@type{number}*/ rA, flag = 0) => InstX(31, rA, rT, rA, 444, flag),
  // mask
  rlwinm: makeInstM(21),
  rlwimi: makeInstM(20),
  // b
  b: makeInstI(18),
  bctr: (/**@type{number|boolean}*/ LK = 0) => InstX(19, 0b10100, 0, 0, 528, LK ? 1 : 0),
  // mflr
  mflr: (/**@type{number}*/ rT) => InstX(31, rT, 8, 0, 339, 0),
  mfctr: (/**@type{number}*/ rT) => InstX(31, rT, 9, 0, 339, 0),
  // mtlr
  mtlr: (/**@type{number}*/ rS) => InstX(31, rS, 8, 0, 467, 0),
  mtctr: (/**@type{number}*/ rS) => InstX(31, rS, 9, 0, 467, 0),
  // cr
  crset: (/**@type{number}*/ B) => InstX(19, B, B, B, 289, 0),
  crclr: (/**@type{number}*/ B) => InstX(19, B, B, B, 193, 0),
  // float
  fmr: (/**@type{number}*/ fT, /**@type{number}*/ fB, Rc = 0) => InstX(63, fT, 0, fB, 72, Rc),
};

export const $load = {
  8: ASM.lbz,
  16: ASM.lhz,
  32: ASM.lwz,
  [-16]: ASM.lha,
  [-32]: ASM.lwz,
  float: ASM.lfs,
};
export const $store = {
  8: ASM.stb,
  16: ASM.sth,
  32: ASM.stw,
  [-16]: ASM.sth,
  [-32]: ASM.stw,
  float: ASM.stfs,
  double: ASM.stfd,
};

/**
 * @param {number} rT
 * @param {number} D
 */
export function liDX(rT, D) {
  if (-0x8000 <= D && D < 0x8000) {
    return [ASM.li(rT, D)];
  } else if ((D & 0xffff) === 0) {
    return [ASM.lis(rT, D >>> 16)];
  } else {
    const h = D >>> 16;
    const l = D & 0xffff;
    return [ASM.lis(rT, h), ASM.ori(rT, rT, l)];
  }
}

/**
 * @param {string} s
 * @param {string} version
 */
export function str2bytes(s, version) {
  /** @type {Record<string, (typeof charInfoJP)[' ']>} */
  const charInfo = version.startsWith('GMSJ')
    ? charInfoJP
    : version === 'GMSE01'
    ? charInfoUS
    : charInfoEU;
  const fmtbuf = Array.from(s).flatMap((c) => {
    const code = charInfo[c]?.code ?? c.charCodeAt(0); // TODO multi-byte invalid char
    return code >= 0x100 ? [code >> 8, code & 0xff] : [code];
  });
  fmtbuf.push(0); // NUL terminated
  return fmtbuf;
}

/**
 * @param {string} s
 * @param {string} version
 */
export const str2hex = (s, version) =>
  str2bytes(s, version)
    .map((x) => x.toString(16).toUpperCase().padStart(2, '0'))
    .join('');

/**
 * @param {string} s
 * @param {string} version
 */
export function str2inst(s, version) {
  const fmtbuf = str2bytes(s, version);
  const fmtlen = fmtbuf.length;
  const fmtlen3 = fmtlen & 3;
  const pad = fmtlen3 ? 4 - fmtlen3 : 0;
  fmtbuf.push(...Array(pad).fill(0));
  const dv = new DataView(Uint8Array.from(fmtbuf).buffer);
  const insts = Array((fmtlen + pad) >> 2)
    .fill(0)
    .map((_, i) => dv.getUint32(i << 2, false));
  return insts;
}

/**
 * @param {number} pc
 * @param {string} [hex]
 */
export const makeProgram = (pc, hex = '') => ({
  pc,
  hex,
  /**
   * @param {number} dst
   * @param {boolean} LL
   */
  b(dst, LL = false) {
    // TODO check overflow
    this.push(ASM.b(dst - this.pc, LL));
  },
  /** @param {number} dst */
  bl(dst) {
    this.b(dst, true);
  },
  /** @param {Inst[]} codes */
  push(...codes) {
    this.hex += codes.map(inst2gecko).join('');
    this.pc += codes.length << 2;
  },
  /** @param {string} data */
  pushHex(data) {
    this.hex += data;
    this.pc += data.length >> 1;
  },
  align() {
    const l4 = this.pc % 4;
    if (l4) {
      const diff = 4 - l4;
      this.hex += ''.padEnd(diff << 1, '0');
      this.pc += diff;
    }
  },
});

/** @param {number} x */
export const inst2gecko = (x) => (x >>> 0).toString(16).toUpperCase().padStart(8, '0');
/** @param {Inst[]} insts */
export const insts2hex = (insts) => insts.map(inst2gecko).join('');

/**
 * @param {{
 *   x: number,
 *   y: number,
 *   fontSize: number,
 *   bgRGB: number,
 *   bgA: number,
 *   bgLeft: number,
 *   bgRight: number,
 *   bgTop: number,
 *   bgBot: number
 * }} opt
 * @param {{width: number, height: number}} size
 **/
export const getFillRectParams = (
  { x, y, fontSize, bgRGB, bgA, bgLeft, bgRight, bgTop, bgBot },
  { width, height },
) => [
  // rect
  x - bgLeft, // x0
  y - fontSize - bgTop, // y0
  x + Math.ceil((width * fontSize) / 20) + bgRight, // x1
  y - fontSize + Math.ceil((height * fontSize) / 20) + bgBot, // y1
  // color
  (bgRGB << 8) | bgA,
];

/**
 * @param {{
 *   x: number,
 *   y: number,
 *   fontSize: number,
 *   fgRGB: number
 *   fgA: number
 *   fgRGB2: number | null
 *   fgA2: number | null
 * }} config
 */
export function getDrawTextOpt({ x, y, fontSize, fgRGB, fgA, fgRGB2, fgA2 }) {
  const colorTop = (fgRGB << 8) | fgA;
  const colorBot = fgRGB2 == null || fgA2 == null ? colorTop : (fgRGB2 << 8) | fgA;
  return [((x & 0xffff) << 16) | (y & 0xffff), fontSize, colorTop, colorBot];
}