path: root/src/preamble.js

// === Auto-generated preamble library stuff ===

//========================================
// Runtime code shared with compiler
//========================================

{{RUNTIME}}

#if ASM_JS
#if RESERVED_FUNCTION_POINTERS
function jsCall() {
  var args = Array.prototype.slice.call(arguments);
  return Runtime.functionPointers[args[0]].apply(null, args.slice(1));
}
#endif
#endif

#if BENCHMARK
Module.realPrint = Module.print;
Module.print = Module.printErr = function(){};
#endif

#if SAFE_HEAP
//========================================
// Debugging tools - Heap
//========================================
var HEAP_WATCHED = [];
var HEAP_HISTORY = [];
function SAFE_HEAP_CLEAR(dest) {
#if SAFE_HEAP_LOG
  Module.print('SAFE_HEAP clear: ' + dest);
#endif
  HEAP_HISTORY[dest] = undefined;
}
var SAFE_HEAP_ERRORS = 0;
var ACCEPTABLE_SAFE_HEAP_ERRORS = 0;

function SAFE_HEAP_ACCESS(dest, type, store, ignore, storeValue) {
  //if (dest === A_NUMBER) Module.print ([dest, type, store, ignore, storeValue] + ' ' + stackTrace()); // Something like this may be useful, in debugging

  assert(dest > 0, 'segmentation fault');

#if USE_TYPED_ARRAYS
  // When using typed arrays, reads over the top of TOTAL_MEMORY will fail silently, so we must
  // correct that by growing TOTAL_MEMORY as needed. Without typed arrays, memory is a normal
  // JS array so it will work (potentially slowly, depending on the engine).
  assert(ignore || dest < Math.max(DYNAMICTOP, STATICTOP));
  assert(ignore || DYNAMICTOP <= TOTAL_MEMORY);
#endif

#if USE_TYPED_ARRAYS == 2
  return; // It is legitimate to violate the load-store assumption in this case
#endif
  if (type && type.charAt(type.length-1) == '*') type = 'i32'; // pointers are ints, for our purposes here
  // Note that this will pass even with unions: You can store X, load X, then store Y and load Y.
  // You cannot, however, do the nonportable act of store X and load Y!
  if (store) {
    HEAP_HISTORY[dest] = ignore ? null : type;
  } else {
#if USE_TYPED_ARRAYS == 0
    if (!HEAP[dest] && HEAP[dest] !== 0 && HEAP[dest] !== false && !ignore) { // false can be the result of a mathop comparator
      var error = true;
      try {
        if (HEAP[dest].toString() === 'NaN') error = false; // NaN is acceptable, as a double value
      } catch(e){}
      if (error) throw('Warning: Reading an invalid value at ' + dest + ' :: ' + stackTrace() + '\n');
    }
#endif
    if (type === null) return;
    var history = HEAP_HISTORY[dest];
    if (history === null) return;
    if (!ignore)
      assert(history, 'Must have a history for a safe heap load! ' + dest + ':' + type); // Warning - bit fields in C structs cause loads+stores for each store, so
                                                                                         //           they will show up here...
//    assert((history && history[0]) /* || HEAP[dest] === 0 */, "Loading from where there was no store! " + dest + ',' + HEAP[dest] + ',' + type + ', \n\n' + stackTrace() + '\n');
//    if (history[0].type !== type) {
    if (history !== type && !ignore) {
      Module.print('Load-store consistency assumption failure! ' + dest);
      Module.print('\n');
      Module.print(JSON.stringify(history));
      Module.print('\n');
      Module.print('LOAD: ' + type + ', ' + stackTrace());
      Module.print('\n');
      SAFE_HEAP_ERRORS++;
      assert(SAFE_HEAP_ERRORS <= ACCEPTABLE_SAFE_HEAP_ERRORS, 'Load-store consistency assumption failure!');
    }
  }
}

function SAFE_HEAP_STORE(dest, value, type, ignore) {
#if SAFE_HEAP_LOG
  Module.print('SAFE_HEAP store: ' + [dest, type, value, ignore]);
#endif

  if (!ignore && !value && (value === null || value === undefined)) {
    throw('Warning: Writing an invalid value of ' + JSON.stringify(value) + ' at ' + dest + ' :: ' + stackTrace() + '\n');
  }
  //if (!ignore && (value === Infinity || value === -Infinity || isNaN(value))) throw [value, typeof value, stackTrace()];

  SAFE_HEAP_ACCESS(dest, type, true, ignore, value);
  if (dest in HEAP_WATCHED) {
    Module.print((new Error()).stack);
    throw "Bad store!" + dest;
  }

#if USE_TYPED_ARRAYS == 2
  // Check alignment
  switch(type) {
    case 'i16': assert(dest % 2 == 0); break;
    case 'i32': assert(dest % 4 == 0); break;
    case 'i64': assert(dest % 8 == 0); break;
    case 'float': assert(dest % 4 == 0); break;
#if DOUBLE_MODE == 1
    case 'double': assert(dest % 4 == 0); break;
#else
    case 'double': assert(dest % 4 == 0); break;
#endif
  }
#endif

  setValue(dest, value, type, 1);
}

function SAFE_HEAP_LOAD(dest, type, unsigned, ignore) {
  SAFE_HEAP_ACCESS(dest, type, false, ignore);

#if SAFE_HEAP_LOG
    Module.print('SAFE_HEAP load: ' + [dest, type, getValue(dest, type, 1), ignore]);
#endif

#if USE_TYPED_ARRAYS == 2
  // Check alignment
  switch(type) {
    case 'i16': assert(dest % 2 == 0); break;
    case 'i32': assert(dest % 4 == 0); break;
    case 'i64': assert(dest % 8 == 0); break;
    case 'float': assert(dest % 4 == 0); break;
#if DOUBLE_MODE == 1
    case 'double': assert(dest % 4 == 0); break;
#else
    case 'double': assert(dest % 4 == 0); break;
#endif
  }
#endif

  var ret = getValue(dest, type, 1);
  if (unsigned) ret = unSign(ret, parseInt(type.substr(1)), 1);
  return ret;
}

function SAFE_HEAP_COPY_HISTORY(dest, src) {
#if SAFE_HEAP_LOG
  Module.print('SAFE_HEAP copy: ' + [dest, src]);
#endif
  HEAP_HISTORY[dest] = HEAP_HISTORY[src];
  SAFE_HEAP_ACCESS(dest, HEAP_HISTORY[dest] || null, true, false);
}

function SAFE_HEAP_FILL_HISTORY(from, to, type) {
#if SAFE_HEAP_LOG
  Module.print('SAFE_HEAP fill: ' + [from, to, type]);
#endif
  for (var i = from; i < to; i++) {
    HEAP_HISTORY[i] = type;
  }
}

//==========================================
#endif

#if CHECK_HEAP_ALIGN
//========================================
// Debugging tools - alignment check
//========================================
function CHECK_ALIGN_8(addr) {
  assert((addr & 7) == 0, "address must be 8-byte aligned, is " + addr + "!");
  return addr;
}
function CHECK_ALIGN_4(addr) {
  assert((addr & 3) == 0, "address must be 4-byte aligned, is " + addr + "!");
  return addr;
}
function CHECK_ALIGN_2(addr) {
  assert((addr & 1) == 0, "address must be 2-byte aligned!");
  return addr;
}
#endif


#if CHECK_OVERFLOWS
//========================================
// Debugging tools - Mathop overflows
//========================================
function CHECK_OVERFLOW(value, bits, ignore, sig) {
  if (ignore) return value;
  var twopbits = Math.pow(2, bits);
  var twopbits1 = Math.pow(2, bits-1);
  // For signedness issue here, see settings.js, CHECK_SIGNED_OVERFLOWS
#if CHECK_SIGNED_OVERFLOWS
  if (value === Infinity || value === -Infinity || value >= twopbits1 || value < -twopbits1) {
    throw 'SignedOverflow';
    if (value === Infinity || value === -Infinity || Math.abs(value) >= twopbits) throw 'Overflow';
  }
#else
  if (value === Infinity || value === -Infinity || Math.abs(value) >= twopbits) {
    throw 'Overflow';
  }
#endif
#if CORRECT_OVERFLOWS
  // Fail on >32 bits - we warned at compile time
  if (bits <= 32) {
    value = value & (twopbits - 1);
  }
#endif
  return value;
}
#endif

#if LABEL_DEBUG
//========================================
// Debugging tools - Code flow progress
//========================================
var INDENT = '';
#endif

#if EXECUTION_TIMEOUT
//========================================
// Debugging tools - Execution timeout
//========================================
var START_TIME = Date.now();
#endif

//========================================
// Runtime essentials
//========================================

var __THREW__ = 0; // Used in checking for thrown exceptions.
#if ASM_JS == 0
var setjmpId = 1; // Used in setjmp/longjmp
var setjmpLabels = {};
#endif

var ABORT = false; // whether we are quitting the application. no code should run after this. set in exit() and abort()
var EXITSTATUS = 0;

var undef = 0;
// tempInt is used for 32-bit signed values or smaller. tempBigInt is used
// for 32-bit unsigned values or more than 32 bits. TODO: audit all uses of tempInt
var tempValue, tempInt, tempBigInt, tempInt2, tempBigInt2, tempPair, tempBigIntI, tempBigIntR, tempBigIntS, tempBigIntP, tempBigIntD;
#if USE_TYPED_ARRAYS == 2
var tempI64, tempI64b;
var tempRet0, tempRet1, tempRet2, tempRet3, tempRet4, tempRet5, tempRet6, tempRet7, tempRet8, tempRet9;
#endif

function assert(condition, text) {
  if (!condition) {
    abort('Assertion failed: ' + text);
  }
}

var globalScope = this;

// C calling interface. A convenient way to call C functions (in C files, or
// defined with extern "C").
//
// Note: LLVM optimizations can inline and remove functions, after which you will not be
//       able to call them. Closure can also do so. To avoid that, add your function to
//       the exports using something like
//
//         -s EXPORTED_FUNCTIONS='["_main", "_myfunc"]'
//
// @param ident      The name of the C function (note that C++ functions will be name-mangled - use extern "C")
// @param returnType The return type of the function, one of the JS types 'number', 'string' or 'array' (use 'number' for any C pointer, and
//                   'array' for JavaScript arrays and typed arrays; note that arrays are 8-bit).
// @param argTypes   An array of the types of arguments for the function (if there are no arguments, this can be ommitted). Types are as in returnType,
//                   except that 'array' is not possible (there is no way for us to know the length of the array)
// @param args       An array of the arguments to the function, as native JS values (as in returnType)
//                   Note that string arguments will be stored on the stack (the JS string will become a C string on the stack).
// @return           The return value, as a native JS value (as in returnType)
function ccall(ident, returnType, argTypes, args) {
  return ccallFunc(getCFunc(ident), returnType, argTypes, args);
}
Module["ccall"] = ccall;

// Returns the C function with a specified identifier (for C++, you need to do manual name mangling)
function getCFunc(ident) {
  try {
    var func = Module['_' + ident]; // closure exported function
    if (!func) func = eval('_' + ident); // explicit lookup
  } catch(e) {
  }
  assert(func, 'Cannot call unknown function ' + ident + ' (perhaps LLVM optimizations or closure removed it?)');
  return func;
}

// Internal function that does a C call using a function, not an identifier
function ccallFunc(func, returnType, argTypes, args) {
  var stack = 0;
  function toC(value, type) {
    if (type == 'string') {
      if (value === null || value === undefined || value === 0) return 0; // null string
      value = intArrayFromString(value);
      type = 'array';
    }
    if (type == 'array') {
      if (!stack) stack = Runtime.stackSave();
      var ret = Runtime.stackAlloc(value.length);
      writeArrayToMemory(value, ret);
      return ret;
    }
    return value;
  }
  function fromC(value, type) {
    if (type == 'string') {
      return Pointer_stringify(value);
    }
    assert(type != 'array');
    return value;
  }
  var i = 0;
  var cArgs = args ? args.map(function(arg) {
    return toC(arg, argTypes[i++]);
  }) : [];
  var ret = fromC(func.apply(null, cArgs), returnType);
  if (stack) Runtime.stackRestore(stack);
  return ret;
}

// Returns a native JS wrapper for a C function. This is similar to ccall, but
// returns a function you can call repeatedly in a normal way. For example:
//
//   var my_function = cwrap('my_c_function', 'number', ['number', 'number']);
//   alert(my_function(5, 22));
//   alert(my_function(99, 12));
//
function cwrap(ident, returnType, argTypes) {
  var func = getCFunc(ident);
  return function() {
    return ccallFunc(func, returnType, argTypes, Array.prototype.slice.call(arguments));
  }
}
Module["cwrap"] = cwrap;

// Sets a value in memory in a dynamic way at run-time. Uses the
// type data. This is the same as makeSetValue, except that
// makeSetValue is done at compile-time and generates the needed
// code then, whereas this function picks the right code at
// run-time.
// Note that setValue and getValue only do *aligned* writes and reads!
// Note that ccall uses JS types as for defining types, while setValue and
// getValue need LLVM types ('i8', 'i32') - this is a lower-level operation
function setValue(ptr, value, type, noSafe) {
  type = type || 'i8';
  if (type.charAt(type.length-1) === '*') type = 'i32'; // pointers are 32-bit
#if SAFE_HEAP
  if (noSafe) {
    switch(type) {
      case 'i1': {{{ makeSetValue('ptr', '0', 'value', 'i1', undefined, undefined, undefined, '1') }}}; break;
      case 'i8': {{{ makeSetValue('ptr', '0', 'value', 'i8', undefined, undefined, undefined, '1') }}}; break;
      case 'i16': {{{ makeSetValue('ptr', '0', 'value', 'i16', undefined, undefined, undefined, '1') }}}; break;
      case 'i32': {{{ makeSetValue('ptr', '0', 'value', 'i32', undefined, undefined, undefined, '1') }}}; break;
      case 'i64': {{{ makeSetValue('ptr', '0', 'value', 'i64', undefined, undefined, undefined, '1') }}}; break;
      case 'float': {{{ makeSetValue('ptr', '0', 'value', 'float', undefined, undefined, undefined, '1') }}}; break;
      case 'double': {{{ makeSetValue('ptr', '0', 'value', 'double', undefined, undefined, undefined, '1') }}}; break;
      default: abort('invalid type for setValue: ' + type);
    }
  } else {
#endif
    switch(type) {
      case 'i1': {{{ makeSetValue('ptr', '0', 'value', 'i1') }}}; break;
      case 'i8': {{{ makeSetValue('ptr', '0', 'value', 'i8') }}}; break;
      case 'i16': {{{ makeSetValue('ptr', '0', 'value', 'i16') }}}; break;
      case 'i32': {{{ makeSetValue('ptr', '0', 'value', 'i32') }}}; break;
      case 'i64': {{{ makeSetValue('ptr', '0', 'value', 'i64') }}}; break;
      case 'float': {{{ makeSetValue('ptr', '0', 'value', 'float') }}}; break;
      case 'double': {{{ makeSetValue('ptr', '0', 'value', 'double') }}}; break;
      default: abort('invalid type for setValue: ' + type);
    }
#if SAFE_HEAP
  }
#endif
}
Module['setValue'] = setValue;

// Parallel to setValue.
function getValue(ptr, type, noSafe) {
  type = type || 'i8';
  if (type.charAt(type.length-1) === '*') type = 'i32'; // pointers are 32-bit
#if SAFE_HEAP
  if (noSafe) {
    switch(type) {
      case 'i1': return {{{ makeGetValue('ptr', '0', 'i1', undefined, undefined, undefined, undefined, '1') }}};
      case 'i8': return {{{ makeGetValue('ptr', '0', 'i8', undefined, undefined, undefined, undefined, '1') }}};
      case 'i16': return {{{ makeGetValue('ptr', '0', 'i16', undefined, undefined, undefined, undefined, '1') }}};
      case 'i32': return {{{ makeGetValue('ptr', '0', 'i32', undefined, undefined, undefined, undefined, '1') }}};
      case 'i64': return {{{ makeGetValue('ptr', '0', 'i64', undefined, undefined, undefined, undefined, '1') }}};
      case 'float': return {{{ makeGetValue('ptr', '0', 'float', undefined, undefined, undefined, undefined, '1') }}};
      case 'double': return {{{ makeGetValue('ptr', '0', 'double', undefined, undefined, undefined, undefined, '1') }}};
      default: abort('invalid type for setValue: ' + type);
    }
  } else {
#endif
    switch(type) {
      case 'i1': return {{{ makeGetValue('ptr', '0', 'i1') }}};
      case 'i8': return {{{ makeGetValue('ptr', '0', 'i8') }}};
      case 'i16': return {{{ makeGetValue('ptr', '0', 'i16') }}};
      case 'i32': return {{{ makeGetValue('ptr', '0', 'i32') }}};
      case 'i64': return {{{ makeGetValue('ptr', '0', 'i64') }}};
      case 'float': return {{{ makeGetValue('ptr', '0', 'float') }}};
      case 'double': return {{{ makeGetValue('ptr', '0', 'double') }}};
      default: abort('invalid type for setValue: ' + type);
    }
#if SAFE_HEAP
  }
#endif
  return null;
}
Module['getValue'] = getValue;

var ALLOC_NORMAL = 0; // Tries to use _malloc()
var ALLOC_STACK = 1; // Lives for the duration of the current function call
var ALLOC_STATIC = 2; // Cannot be freed
var ALLOC_DYNAMIC = 3; // Cannot be freed except through sbrk
var ALLOC_NONE = 4; // Do not allocate
Module['ALLOC_NORMAL'] = ALLOC_NORMAL;
Module['ALLOC_STACK'] = ALLOC_STACK;
Module['ALLOC_STATIC'] = ALLOC_STATIC;
Module['ALLOC_DYNAMIC'] = ALLOC_DYNAMIC;
Module['ALLOC_NONE'] = ALLOC_NONE;

// allocate(): This is for internal use. You can use it yourself as well, but the interface
//             is a little tricky (see docs right below). The reason is that it is optimized
//             for multiple syntaxes to save space in generated code. So you should
//             normally not use allocate(), and instead allocate memory using _malloc(),
//             initialize it with setValue(), and so forth.
// @slab: An array of data, or a number. If a number, then the size of the block to allocate,
//        in *bytes* (note that this is sometimes confusing: the next parameter does not
//        affect this!)
// @types: Either an array of types, one for each byte (or 0 if no type at that position),
//         or a single type which is used for the entire block. This only matters if there
//         is initial data - if @slab is a number, then this does not matter at all and is
//         ignored.
// @allocator: How to allocate memory, see ALLOC_*
function allocate(slab, types, allocator, ptr) {
  var zeroinit, size;
  if (typeof slab === 'number') {
    zeroinit = true;
    size = slab;
  } else {
    zeroinit = false;
    size = slab.length;
  }

  var singleType = typeof types === 'string' ? types : null;

  var ret;
  if (allocator == ALLOC_NONE) {
    ret = ptr;
  } else {
    ret = [_malloc, Runtime.stackAlloc, Runtime.staticAlloc, Runtime.dynamicAlloc][allocator === undefined ? ALLOC_STATIC : allocator](Math.max(size, singleType ? 1 : types.length));
  }

  if (zeroinit) {
    var ptr = ret, stop;
#if USE_TYPED_ARRAYS == 2
    assert((ret & 3) == 0);
    stop = ret + (size & ~3);
    for (; ptr < stop; ptr += 4) {
      {{{ makeSetValue('ptr', '0', '0', 'i32', null, true) }}};
    }
#endif
    stop = ret + size;
    while (ptr < stop) {
      {{{ makeSetValue('ptr++', '0', '0', 'i8', null, true) }}};
    }
    return ret;
  }

#if USE_TYPED_ARRAYS == 2
  if (singleType === 'i8') {
    if (slab.subarray || slab.slice) {
      HEAPU8.set(slab, ret);
    } else {
      HEAPU8.set(new Uint8Array(slab), ret);
    }
    return ret;
  }
#endif

  var i = 0, type, typeSize, previousType;
  while (i < size) {
    var curr = slab[i];

    if (typeof curr === 'function') {
      curr = Runtime.getFunctionIndex(curr);
    }

    type = singleType || types[i];
    if (type === 0) {
      i++;
      continue;
    }
#if ASSERTIONS
    assert(type, 'Must know what type to store in allocate!');
#endif

#if USE_TYPED_ARRAYS == 2
    if (type == 'i64') type = 'i32'; // special case: we have one i32 here, and one i32 later
#endif

    setValue(ret+i, curr, type);

    // no need to look up size unless type changes, so cache it
    if (previousType !== type) {
      typeSize = Runtime.getNativeTypeSize(type);
      previousType = type;
    }
    i += typeSize;
  }

  return ret;
}
Module['allocate'] = allocate;

function Pointer_stringify(ptr, /* optional */ length) {
  // TODO: use TextDecoder
  // Find the length, and check for UTF while doing so
  var hasUtf = false;
  var t;
  var i = 0;
  while (1) {
#if ASSERTIONS
    assert(ptr + i < TOTAL_MEMORY);
#endif
    t = {{{ makeGetValue('ptr', 'i', 'i8', 0, 1) }}};
    if (t >= 128) hasUtf = true;
    else if (t == 0 && !length) break;
    i++;
    if (length && i == length) break;
  }
  if (!length) length = i;

  var ret = '';

#if USE_TYPED_ARRAYS == 2
  if (!hasUtf) {
    var MAX_CHUNK = 1024; // split up into chunks, because .apply on a huge string can overflow the stack
    var curr;
    while (length > 0) {
      curr = String.fromCharCode.apply(String, HEAPU8.subarray(ptr, ptr + Math.min(length, MAX_CHUNK)));
      ret = ret ? ret + curr : curr;
      ptr += MAX_CHUNK;
      length -= MAX_CHUNK;
    }
    return ret;
  }
#endif

  var utf8 = new Runtime.UTF8Processor();
  for (i = 0; i < length; i++) {
#if ASSERTIONS
    assert(ptr + i < TOTAL_MEMORY);
#endif
    t = {{{ makeGetValue('ptr', 'i', 'i8', 0, 1) }}};
    ret += utf8.processCChar(t);
  }
  return ret;
}
Module['Pointer_stringify'] = Pointer_stringify;

// Given a pointer 'ptr' to a null-terminated UTF16LE-encoded string in the emscripten HEAP, returns
// a copy of that string as a Javascript String object.
function UTF16ToString(ptr) {
  var i = 0;

  var str = '';
  while (1) {
    var codeUnit = {{{ makeGetValue('ptr', 'i*2', 'i16') }}};
    if (codeUnit == 0)
      return str;
    ++i;
    // fromCharCode constructs a character from a UTF-16 code unit, so we can pass the UTF16 string right through.
    str += String.fromCharCode(codeUnit);
  }
}
Module['UTF16ToString'] = UTF16ToString;

// Copies the given Javascript String object 'str' to the emscripten HEAP at address 'outPtr', 
// null-terminated and encoded in UTF16LE form. The copy will require at most (str.length*2+1)*2 bytes of space in the HEAP.
function stringToUTF16(str, outPtr) {
  for(var i = 0; i < str.length; ++i) {
    // charCodeAt returns a UTF-16 encoded code unit, so it can be directly written to the HEAP.
    var codeUnit = str.charCodeAt(i); // possibly a lead surrogate
    {{{ makeSetValue('outPtr', 'i*2', 'codeUnit', 'i16') }}}
  }
  // Null-terminate the pointer to the HEAP.
  {{{ makeSetValue('outPtr', 'str.length*2', 0, 'i16') }}}
}
Module['stringToUTF16'] = stringToUTF16;

// Given a pointer 'ptr' to a null-terminated UTF32LE-encoded string in the emscripten HEAP, returns
// a copy of that string as a Javascript String object.
function UTF32ToString(ptr) {
  var i = 0;

  var str = '';
  while (1) {
    var utf32 = {{{ makeGetValue('ptr', 'i*4', 'i32') }}};
    if (utf32 == 0)
      return str;
    ++i;
    // Gotcha: fromCharCode constructs a character from a UTF-16 encoded code (pair), not from a Unicode code point! So encode the code point to UTF-16 for constructing.
    if (utf32 >= 0x10000) {
      var ch = utf32 - 0x10000;
      str += String.fromCharCode(0xD800 | (ch >> 10), 0xDC00 | (ch & 0x3FF));
    } else {
      str += String.fromCharCode(utf32);
    }
  }
}
Module['UTF32ToString'] = UTF32ToString;

// Copies the given Javascript String object 'str' to the emscripten HEAP at address 'outPtr', 
// null-terminated and encoded in UTF32LE form. The copy will require at most (str.length+1)*4 bytes of space in the HEAP,
// but can use less, since str.length does not return the number of characters in the string, but the number of UTF-16 code units in the string.
function stringToUTF32(str, outPtr) {
  var iChar = 0;
  for(var iCodeUnit = 0; iCodeUnit < str.length; ++iCodeUnit) {
    // Gotcha: charCodeAt returns a 16-bit word that is a UTF-16 encoded code unit, not a Unicode code point of the character! We must decode the string to UTF-32 to the heap.
    var codeUnit = str.charCodeAt(iCodeUnit); // possibly a lead surrogate
    if (codeUnit >= 0xD800 && codeUnit <= 0xDFFF) {
      var trailSurrogate = str.charCodeAt(++iCodeUnit);
      codeUnit = 0x10000 + ((codeUnit & 0x3FF) << 10) | (trailSurrogate & 0x3FF);
    }
    {{{ makeSetValue('outPtr', 'iChar*4', 'codeUnit', 'i32') }}}
    ++iChar;
  }
  // Null-terminate the pointer to the HEAP.
  {{{ makeSetValue('outPtr', 'iChar*4', 0, 'i32') }}}
}
Module['stringToUTF32'] = stringToUTF32;

function demangle(func) {
  try {
    if (typeof func === 'number') func = Pointer_stringify(func);
    if (func[0] !== '_') return func;
    if (func[1] !== '_') return func; // C function
    if (func[2] !== 'Z') return func;
    var i = 3;
    // params, etc.
    var basicTypes = {
      'v': 'void',
      'b': 'bool',
      'c': 'char',
      's': 'short',
      'i': 'int',
      'l': 'long',
      'f': 'float',
      'd': 'double',
      'w': 'wchar_t',
      'a': 'signed char',
      'h': 'unsigned char',
      't': 'unsigned short',
      'j': 'unsigned int',
      'm': 'unsigned long',
      'x': 'long long',
      'y': 'unsigned long long',
      'z': '...'
    };
    function dump(x) {
      //return;
      if (x) Module.print(x);
      Module.print(func);
      var pre = '';
      for (var a = 0; a < i; a++) pre += ' ';
      Module.print (pre + '^');
    }
    var subs = [];
    function parseNested() {
      i++;
      if (func[i] === 'K') i++;
      var parts = [];
      while (func[i] !== 'E') {
        if (func[i] === 'S') { // substitution
          i++;
          var next = func.indexOf('_', i);
          var num = func.substring(i, next) || 0;
          parts.push(subs[num] || '?');
          i = next+1;
          continue;
        }
        var size = parseInt(func.substr(i));
        var pre = size.toString().length;
        if (!size || !pre) { i--; break; } // counter i++ below us
        var curr = func.substr(i + pre, size);
        parts.push(curr);
        subs.push(curr);
        i += pre + size;
      }
      i++; // skip E
      return parts;
    }
    function parse(rawList, limit, allowVoid) { // main parser
      limit = limit || Infinity;
      var ret = '', list = [];
      function flushList() {
        return '(' + list.join(', ') + ')';
      }
      var name;
      if (func[i] !== 'N') {
        // not namespaced
        if (func[i] === 'K') i++;
        var size = parseInt(func.substr(i));
        if (size) {
          var pre = size.toString().length;
          name = func.substr(i + pre, size);
          i += pre + size;
        }
      } else {
        // namespaced N-E
        name = parseNested().join('::');
        limit--;
        if (limit === 0) return rawList ? [name] : name;
      }
      if (func[i] === 'I') {
        i++;
        var iList = parse(true);
        var iRet = parse(true, 1, true);
        ret += iRet[0] + ' ' + name + '<' + iList.join(', ') + '>';
      } else {
        ret = name;
      }
      paramLoop: while (i < func.length && limit-- > 0) {
        //dump('paramLoop');
        var c = func[i++];
        if (c in basicTypes) {
          list.push(basicTypes[c]);
        } else {
          switch (c) {
            case 'P': list.push(parse(true, 1, true)[0] + '*'); break; // pointer
            case 'R': list.push(parse(true, 1, true)[0] + '&'); break; // reference
            case 'L': { // literal
              i++; // skip basic type
              var end = func.indexOf('E', i);
              var size = end - i;
              list.push(func.substr(i, size));
              i += size + 2; // size + 'EE'
              break;
            }
            case 'A': { // array
              var size = parseInt(func.substr(i));
              i += size.toString().length;
              if (func[i] !== '_') throw '?';
              i++; // skip _
              list.push(parse(true, 1, true)[0] + ' [' + size + ']');
              break;
            }
            case 'E': break paramLoop;
            default: ret += '?' + c; break paramLoop;
          }
        }
      }
      if (!allowVoid && list.length === 1 && list[0] === 'void') list = []; // avoid (void)
      return rawList ? list : ret + flushList();
    }
    return parse();
  } catch(e) {
    return func;
  }
}

function demangleAll(text) {
  return text.replace(/__Z[\w\d_]+/g, function(x) { var y = demangle(x); return x === y ? x : (x + ' [' + y + ']') });
}

function stackTrace() {
  var stack = new Error().stack;
  return stack ? demangleAll(stack) : '(no stack trace available)'; // Stack trace is not available at least on IE10 and Safari 6.
}

// Memory management

var PAGE_SIZE = 4096;
function alignMemoryPage(x) {
  return (x+4095)&-4096;
}

var HEAP;
#if USE_TYPED_ARRAYS == 1
var IHEAP, IHEAPU;
#if USE_FHEAP
var FHEAP;
#endif
#endif
#if USE_TYPED_ARRAYS == 2
var HEAP8, HEAPU8, HEAP16, HEAPU16, HEAP32, HEAPU32, HEAPF32, HEAPF64;
#endif

var STATIC_BASE = 0, STATICTOP = 0, staticSealed = false; // static area
var STACK_BASE = 0, STACKTOP = 0, STACK_MAX = 0; // stack area
var DYNAMIC_BASE = 0, DYNAMICTOP = 0; // dynamic area handled by sbrk

#if USE_TYPED_ARRAYS
function enlargeMemory() {
#if ALLOW_MEMORY_GROWTH == 0
#if ASM_JS == 0
  abort('Cannot enlarge memory arrays. Either (1) compile with -s TOTAL_MEMORY=X with X higher than the current value ' + TOTAL_MEMORY + ', (2) compile with ALLOW_MEMORY_GROWTH which adjusts the size at runtime but prevents some optimizations, or (3) set Module.TOTAL_MEMORY before the program runs.');
#else
  abort('Cannot enlarge memory arrays in asm.js. Either (1) compile with -s TOTAL_MEMORY=X with X higher than the current value ' + TOTAL_MEMORY + ', or (2) set Module.TOTAL_MEMORY before the program runs.');
#endif
#else
  // TOTAL_MEMORY is the current size of the actual array, and DYNAMICTOP is the new top.
#if ASSERTIONS
  Module.printErr('Warning: Enlarging memory arrays, this is not fast, and ALLOW_MEMORY_GROWTH is not fully tested with all optimizations on! ' + [DYNAMICTOP, TOTAL_MEMORY]); // We perform safe elimination instead of elimination in this mode, but if you see this error, try to disable it and other optimizations entirely
  assert(DYNAMICTOP >= TOTAL_MEMORY);
  assert(TOTAL_MEMORY > 4); // So the loop below will not be infinite
#endif
  while (TOTAL_MEMORY <= DYNAMICTOP) { // Simple heuristic. Override enlargeMemory() if your program has something more optimal for it
    TOTAL_MEMORY = alignMemoryPage(2*TOTAL_MEMORY);
  }
  assert(TOTAL_MEMORY <= Math.pow(2, 30)); // 2^30==1GB is a practical maximum - 2^31 is already close to possible negative numbers etc.
#if USE_TYPED_ARRAYS == 1
  var oldIHEAP = IHEAP;
  Module['HEAP'] = Module['IHEAP'] = HEAP = IHEAP = new Int32Array(TOTAL_MEMORY);
  IHEAP.set(oldIHEAP);
  IHEAPU = new Uint32Array(IHEAP.buffer);
#if USE_FHEAP
  var oldFHEAP = FHEAP;
  Module['FHEAP'] = FHEAP = new Float64Array(TOTAL_MEMORY);
  FHEAP.set(oldFHEAP);
#endif
#endif
#if USE_TYPED_ARRAYS == 2
  var oldHEAP8 = HEAP8;
  var buffer = new ArrayBuffer(TOTAL_MEMORY);
  Module['HEAP8'] = HEAP8 = new Int8Array(buffer);
  Module['HEAP16'] = HEAP16 = new Int16Array(buffer);
  Module['HEAP32'] = HEAP32 = new Int32Array(buffer);
  Module['HEAPU8'] = HEAPU8 = new Uint8Array(buffer);
  Module['HEAPU16'] = HEAPU16 = new Uint16Array(buffer);
  Module['HEAPU32'] = HEAPU32 = new Uint32Array(buffer);
  Module['HEAPF32'] = HEAPF32 = new Float32Array(buffer);
  Module['HEAPF64'] = HEAPF64 = new Float64Array(buffer);
  HEAP8.set(oldHEAP8);
#endif
#endif
}
#endif

var TOTAL_STACK = Module['TOTAL_STACK'] || {{{ TOTAL_STACK }}};
var TOTAL_MEMORY = Module['TOTAL_MEMORY'] || {{{ TOTAL_MEMORY }}};
var FAST_MEMORY = Module['FAST_MEMORY'] || {{{ FAST_MEMORY }}};

// Initialize the runtime's memory
#if USE_TYPED_ARRAYS
// check for full engine support (use string 'subarray' to avoid closure compiler confusion)
assert(typeof Int32Array !== 'undefined' && typeof Float64Array !== 'undefined' && !!(new Int32Array(1)['subarray']) && !!(new Int32Array(1)['set']),
       'Cannot fallback to non-typed array case: Code is too specialized');

#if USE_TYPED_ARRAYS == 1
HEAP = IHEAP = new Int32Array(TOTAL_MEMORY);
IHEAPU = new Uint32Array(IHEAP.buffer);
#if USE_FHEAP
FHEAP = new Float64Array(TOTAL_MEMORY);
#endif
#endif
#if USE_TYPED_ARRAYS == 2
var buffer = new ArrayBuffer(TOTAL_MEMORY);
HEAP8 = new Int8Array(buffer);
HEAP16 = new Int16Array(buffer);
HEAP32 = new Int32Array(buffer);
HEAPU8 = new Uint8Array(buffer);
HEAPU16 = new Uint16Array(buffer);
HEAPU32 = new Uint32Array(buffer);
HEAPF32 = new Float32Array(buffer);
HEAPF64 = new Float64Array(buffer);

// Endianness check (note: assumes compiler arch was little-endian)
HEAP32[0] = 255;
assert(HEAPU8[0] === 255 && HEAPU8[3] === 0, 'Typed arrays 2 must be run on a little-endian system');
#endif
#else
// Make sure that our HEAP is implemented as a flat array.
HEAP = []; // Hinting at the size with |new Array(TOTAL_MEMORY)| should help in theory but makes v8 much slower
for (var i = 0; i < FAST_MEMORY; i++) {
  HEAP[i] = 0; // XXX We do *not* use {{| makeSetValue(0, 'i', 0, 'null') |}} here, since this is done just to optimize runtime speed
}
#endif

Module['HEAP'] = HEAP;
#if USE_TYPED_ARRAYS == 1
Module['IHEAP'] = IHEAP;
#if USE_FHEAP
Module['FHEAP'] = FHEAP;
#endif
#endif
#if USE_TYPED_ARRAYS == 2
Module['HEAP8'] = HEAP8;
Module['HEAP16'] = HEAP16;
Module['HEAP32'] = HEAP32;
Module['HEAPU8'] = HEAPU8;
Module['HEAPU16'] = HEAPU16;
Module['HEAPU32'] = HEAPU32;
Module['HEAPF32'] = HEAPF32;
Module['HEAPF64'] = HEAPF64;
#endif

function callRuntimeCallbacks(callbacks) {
  while(callbacks.length > 0) {
    var callback = callbacks.shift();
    if (typeof callback == 'function') {
      callback();
      continue;
    }
    var func = callback.func;
    if (typeof func === 'number') {
      if (callback.arg === undefined) {
        Runtime.dynCall('v', func);
      } else {
        Runtime.dynCall('vi', func, [callback.arg]);
      }
    } else {
      func(callback.arg === undefined ? null : callback.arg);
    }
  }
}

var __ATPRERUN__  = []; // functions called before the runtime is initialized
var __ATINIT__    = []; // functions called during startup
var __ATMAIN__    = []; // functions called when main() is to be run
var __ATEXIT__    = []; // functions called during shutdown
var __ATPOSTRUN__ = []; // functions called after the runtime has exited

var runtimeInitialized = false;

function preRun() {
  // compatibility - merge in anything from Module['preRun'] at this time
  if (Module['preRun']) {
    if (typeof Module['preRun'] == 'function') Module['preRun'] = [Module['preRun']];
    while (Module['preRun'].length) {
      addOnPreRun(Module['preRun'].shift());
    }
  }
  callRuntimeCallbacks(__ATPRERUN__);
}

function ensureInitRuntime() {
  if (runtimeInitialized) return;
  runtimeInitialized = true;
  callRuntimeCallbacks(__ATINIT__);
}

function preMain() {
  callRuntimeCallbacks(__ATMAIN__);
}

function exitRuntime() {
  callRuntimeCallbacks(__ATEXIT__);
}

function postRun() {
  // compatibility - merge in anything from Module['postRun'] at this time
  if (Module['postRun']) {
    if (typeof Module['postRun'] == 'function') Module['postRun'] = [Module['postRun']];
    while (Module['postRun'].length) {
      addOnPostRun(Module['postRun'].shift());
    }
  }
  callRuntimeCallbacks(__ATPOSTRUN__);
}

function addOnPreRun(cb) {
  __ATPRERUN__.unshift(cb);
}
Module['addOnPreRun'] = Module.addOnPreRun = addOnPreRun;

function addOnInit(cb) {
  __ATINIT__.unshift(cb);
}
Module['addOnInit'] = Module.addOnInit = addOnInit;

function addOnPreMain(cb) {
  __ATMAIN__.unshift(cb);
}
Module['addOnPreMain'] = Module.addOnPreMain = addOnPreMain;

function addOnExit(cb) {
  __ATEXIT__.unshift(cb);
}
Module['addOnExit'] = Module.addOnExit = addOnExit;

function addOnPostRun(cb) {
  __ATPOSTRUN__.unshift(cb);
}
Module['addOnPostRun'] = Module.addOnPostRun = addOnPostRun;

// Tools

// This processes a JS string into a C-line array of numbers, 0-terminated.
// For LLVM-originating strings, see parser.js:parseLLVMString function
function intArrayFromString(stringy, dontAddNull, length /* optional */) {
  var ret = (new Runtime.UTF8Processor()).processJSString(stringy);
  if (length) {
    ret.length = length;
  }
  if (!dontAddNull) {
    ret.push(0);
  }
  return ret;
}
Module['intArrayFromString'] = intArrayFromString;

function intArrayToString(array) {
  var ret = [];
  for (var i = 0; i < array.length; i++) {
    var chr = array[i];
    if (chr > 0xFF) {
#if ASSERTIONS
        assert(false, 'Character code ' + chr + ' (' + String.fromCharCode(chr) + ')  at offset ' + i + ' not in 0x00-0xFF.');
#endif
      chr &= 0xFF;
    }
    ret.push(String.fromCharCode(chr));
  }
  return ret.join('');
}
Module['intArrayToString'] = intArrayToString;

// Write a Javascript array to somewhere in the heap
function writeStringToMemory(string, buffer, dontAddNull) {
  var array = intArrayFromString(string, dontAddNull);
  var i = 0;
  while (i < array.length) {
    var chr = array[i];
    {{{ makeSetValue('buffer', 'i', 'chr', 'i8') }}}
    i = i + 1;
  }
}
Module['writeStringToMemory'] = writeStringToMemory;

function writeArrayToMemory(array, buffer) {
  for (var i = 0; i < array.length; i++) {
    {{{ makeSetValue('buffer', 'i', 'array[i]', 'i8') }}};
  }
}
Module['writeArrayToMemory'] = writeArrayToMemory;

function writeAsciiToMemory(str, buffer, dontAddNull) {
  for (var i = 0; i < str.length; i++) {
#if ASSERTIONS
    assert(str.charCodeAt(i) === str.charCodeAt(i)&0xff);
#endif
    {{{ makeSetValue('buffer', 'i', 'str.charCodeAt(i)', 'i8') }}}
  }
  if (!dontAddNull) {{{ makeSetValue('buffer', 'str.length', 0, 'i8') }}}
}
Module['writeAsciiToMemory'] = writeAsciiToMemory;

{{{ unSign }}}
{{{ reSign }}}

#if PRECISE_I32_MUL
if (!Math['imul']) Math['imul'] = function(a, b) {
  var ah  = a >>> 16;
  var al = a & 0xffff;
  var bh  = b >>> 16;
  var bl = b & 0xffff;
  return (al*bl + ((ah*bl + al*bh) << 16))|0;
};
#else
Math['imul'] = function(a, b) {
  return (a*b)|0; // fast but imprecise
};
#endif
Math.imul = Math['imul'];

#if TO_FLOAT32
if (!Math['toFloat32']) Math['toFloat32'] = function(x) {
  return x;
};
Math.toFloat32 = Math['toFloat32'];
#endif

var Math_abs = Math.abs;
var Math_cos = Math.cos;
var Math_sin = Math.sin;
var Math_tan = Math.tan;
var Math_acos = Math.acos;
var Math_asin = Math.asin;
var Math_atan = Math.atan;
var Math_atan2 = Math.atan2;
var Math_exp = Math.exp;
var Math_log = Math.log;
var Math_sqrt = Math.sqrt;
var Math_ceil = Math.ceil;
var Math_floor = Math.floor;
var Math_pow = Math.pow;
var Math_imul = Math.imul;
var Math_toFloat32 = Math.toFloat32;
var Math_min = Math.min;

// A counter of dependencies for calling run(). If we need to
// do asynchronous work before running, increment this and
// decrement it. Incrementing must happen in a place like
// PRE_RUN_ADDITIONS (used by emcc to add file preloading).
// Note that you can add dependencies in preRun, even though
// it happens right before run - run will be postponed until
// the dependencies are met.
var runDependencies = 0;
var runDependencyTracking = {};
var runDependencyWatcher = null;
var dependenciesFulfilled = null; // overridden to take different actions when all run dependencies are fulfilled

function addRunDependency(id) {
  runDependencies++;
  if (Module['monitorRunDependencies']) {
    Module['monitorRunDependencies'](runDependencies);
  }
  if (id) {
    assert(!runDependencyTracking[id]);
    runDependencyTracking[id] = 1;
#if ASSERTIONS
    if (runDependencyWatcher === null && typeof setInterval !== 'undefined') {
      // Check for missing dependencies every few seconds
      runDependencyWatcher = setInterval(function() {
        var shown = false;
        for (var dep in runDependencyTracking) {
          if (!shown) {
            shown = true;
            Module.printErr('still waiting on run dependencies:');
          }
          Module.printErr('dependency: ' + dep);
        }
        if (shown) {
          Module.printErr('(end of list)');
        }
      }, 10000);
    }
#endif
  } else {
    Module.printErr('warning: run dependency added without ID');
  }
}
Module['addRunDependency'] = addRunDependency;
function removeRunDependency(id) {
  runDependencies--;
  if (Module['monitorRunDependencies']) {
    Module['monitorRunDependencies'](runDependencies);
  }
  if (id) {
    assert(runDependencyTracking[id]);
    delete runDependencyTracking[id];
  } else {
    Module.printErr('warning: run dependency removed without ID');
  }
  if (runDependencies == 0) {
    if (runDependencyWatcher !== null) {
      clearInterval(runDependencyWatcher);
      runDependencyWatcher = null;
    }
    if (dependenciesFulfilled) {
      var callback = dependenciesFulfilled;
      dependenciesFulfilled = null;
      callback(); // can add another dependenciesFulfilled
    }
  }
}
Module['removeRunDependency'] = removeRunDependency;

Module["preloadedImages"] = {}; // maps url to image data
Module["preloadedAudios"] = {}; // maps url to audio data

#if PGO
var PGOMonitor = {
  called: {},
  dump: function() {
    var dead = [];
    for (var i = 0; i < this.allGenerated.length; i++) {
      var func = this.allGenerated[i];
      if (!this.called[func]) dead.push(func);
    }
    Module.print('-s DEAD_FUNCTIONS=\'' + JSON.stringify(dead) + '\'\n');
  }
};
Module['PGOMonitor'] = PGOMonitor;
__ATEXIT__.push({ func: function() { PGOMonitor.dump() } });
addOnPreRun(function() { addRunDependency('pgo') });
#endif

var memoryInitializer = null;

// === Body ===