jsifier.js

//"use strict";

// Convert analyzed data to javascript. Everything has already been calculated
// before this stage, which just does the final conversion to JavaScript.

// Handy sets

var STRUCT_LIST = set('struct', 'list');

var addedLibraryItems = {};
var asmLibraryFunctions = [];

var SETJMP_LABEL = -1;

var INDENTATION = ' ';

var functionStubSigs = {};

// JSifier
function JSify(data, functionsOnly) {
  //B.start('jsifier');
  var mainPass = !functionsOnly;

  var itemsDict = { type: [], GlobalVariableStub: [], functionStub: [], function: [], GlobalVariable: [], GlobalVariablePostSet: [] };

  if (mainPass) {
    var shellFile = SHELL_FILE ? SHELL_FILE : (BUILD_AS_SHARED_LIB || SIDE_MODULE ? 'shell_sharedlib.js' : 'shell.js');

    // We will start to print out the data, but must do so carefully - we are
    // dealing with potentially *huge* strings. Convenient replacements and
    // manipulations may create in-memory copies, and we may OOM.
    //
    // Final shape that will be created:
    //    shell
    //      (body)
    //        preamble
    //          runtime
    //        generated code
    //        postamble
    //          global_vars
    //
    // First, we print out everything until the generated code. Then the
    // functions will print themselves out as they are parsed. Finally, we
    // will call finalCombiner in the main pass, to print out everything
    // else. This lets us not hold any strings in memory, we simply print
    // things out as they are ready.

    var shellParts = read(shellFile).split('{{BODY}}');
    print(processMacros(preprocess(shellParts[0], shellFile)));
    var preFile = BUILD_AS_SHARED_LIB || SIDE_MODULE ? 'preamble_sharedlib.js' : 'preamble.js';
    var pre = processMacros(preprocess(read(preFile).replace('{{RUNTIME}}', getRuntime()), preFile));
    print(pre);
  }

  if (mainPass) {
    // Add additional necessary items for the main pass. We can now do this since types are parsed (types can be used through
    // generateStructInfo in library.js)
    //B.start('jsifier-libload');
    LibraryManager.load();
    //B.stop('jsifier-libload');

    var libFuncsToInclude;
    if (INCLUDE_FULL_LIBRARY) {
      assert(!(BUILD_AS_SHARED_LIB || SIDE_MODULE), 'Cannot have both INCLUDE_FULL_LIBRARY and BUILD_AS_SHARED_LIB/SIDE_MODULE set.')
      libFuncsToInclude = (MAIN_MODULE || SIDE_MODULE) ? DEFAULT_LIBRARY_FUNCS_TO_INCLUDE.slice(0) : [];
      for (var key in LibraryManager.library) {
        if (!key.match(/__(deps|postset|inline|asm|sig)$/)) {
          libFuncsToInclude.push(key);
        }
      }
      // mark implemented functions as already added (so if memcpy is in the forced full JS library, but also done in C, we just need the C)
      for (var added in IMPLEMENTED_FUNCTIONS) {
        addedLibraryItems[added.substr(1)] = true;
      }
    } else {
      libFuncsToInclude = DEFAULT_LIBRARY_FUNCS_TO_INCLUDE;
    }
    libFuncsToInclude.forEach(function(ident) {
      var finalName = '_' + ident;
      if (ident[0] === '$') {
        finalName = ident.substr(1);
      }
      data.functionStubs.push({
        intertype: 'functionStub',
        finalName: finalName,
        ident: '_' + ident
      });
    });
  }

  function processLibraryFunction(snippet, ident, finalName) {
    // It is possible that when printing the function as a string on Windows, the js interpreter we are in returns the string with Windows
    // line endings \r\n. This is undesirable, since line endings are managed in the form \n in the output for binary file writes, so
    // make sure the endings are uniform.
    snippet = snippet.toString().replace(/\r\n/gm,"\n");
    assert(snippet.indexOf('XXX missing C define') == -1,
           'Trying to include a library function with missing C defines: ' + finalName + ' | ' + snippet);

    // name the function; overwrite if it's already named
    snippet = snippet.replace(/function(?:\s+([^(]+))?\s*\(/, 'function ' + finalName + '(');
    if (LIBRARY_DEBUG && !LibraryManager.library[ident + '__asm']) {
      snippet = snippet.replace('{', '{ var ret = (function() { if (Runtime.debug) Module.printErr("[library call:' + finalName + ': " + Array.prototype.slice.call(arguments).map(Runtime.prettyPrint) + "]"); ');
      snippet = snippet.substr(0, snippet.length-1) + '}).apply(this, arguments); if (Runtime.debug && typeof ret !== "undefined") Module.printErr("  [     return:" + Runtime.prettyPrint(ret)); return ret; \n}';
    }
    return snippet;
  }

  // functionStub
  function functionStubHandler(item) {
    // special logic
    if (item.ident.startsWith('___cxa_find_matching_catch_')) {
      var num = +item.ident.split('_').slice(-1)[0];
      LibraryManager.library[item.ident.substr(1)] = function() {
        return ___cxa_find_matching_catch.apply(null, arguments);
      };
    }

    // note the signature
    if (item.returnType && item.params) {
      functionStubSigs[item.ident] = Functions.getSignature(item.returnType.text, item.params.map(function(arg) { return arg.type }), false);
    }

    function addFromLibrary(ident) {
      if (ident in addedLibraryItems) return '';
      addedLibraryItems[ident] = true;

      // dependencies can be JS functions, which we just run
      if (typeof ident == 'function') return ident();

      // $ident's are special, we do not prefix them with a '_'.
      if (ident[0] === '$') {
        var finalName = ident.substr(1);
      } else {
        var finalName = '_' + ident;
      }

      // Don't replace implemented functions with library ones (which can happen when we add dependencies).
      // Note: We don't return the dependencies here. Be careful not to end up where this matters
      if (finalName in Functions.implementedFunctions) return '';

      var noExport = false;

      if ((!LibraryManager.library.hasOwnProperty(ident) && !LibraryManager.library.hasOwnProperty(ident + '__inline')) || SIDE_MODULE) {
        if (!(finalName in IMPLEMENTED_FUNCTIONS)) {
          if (VERBOSE || ident.substr(0, 11) !== 'emscripten_') { // avoid warning on emscripten_* functions which are for internal usage anyhow
            if (!LINKABLE) {
              if (ERROR_ON_UNDEFINED_SYMBOLS) error('unresolved symbol: ' + ident);
              else if (VERBOSE || WARN_ON_UNDEFINED_SYMBOLS) warn('unresolved symbol: ' + ident);
            }
          }
        }
        if (!(MAIN_MODULE || SIDE_MODULE)) {
          // emit a stub that will fail at runtime
          LibraryManager.library[shortident] = new Function("Module['printErr']('missing function: " + shortident + "'); abort(-1);");
        } else {
          var target = (MAIN_MODULE ? '' : 'parent') + "Module['_" + shortident + "']";
          var assertion = '';
          if (ASSERTIONS) assertion = 'if (!' + target + ') abort("external function \'' + shortident + '\' is missing. perhaps a side module was not linked in? if this function was expected to arrive from a system library, try to build the MAIN_MODULE with EMCC_FORCE_STDLIBS=1 in the environment");';
          LibraryManager.library[shortident] = new Function(assertion + "return " + target + ".apply(null, arguments);");
          if (SIDE_MODULE) {
            // no dependencies, just emit the thunk
            Functions.libraryFunctions[finalName] = 1;
            return processLibraryFunction(LibraryManager.library[shortident], ident, finalName);
          }
          noExport = true;
        }
      }

      var snippet = LibraryManager.library[ident];
      var redirectedIdent = null;
      var deps = LibraryManager.library[ident + '__deps'] || [];
      deps.forEach(function(dep) {
        if (typeof snippet === 'string' && !(dep in LibraryManager.library)) warn('missing library dependency ' + dep + ', make sure you are compiling with the right options (see #ifdefs in src/library*.js)');
      });
      var isFunction = false;

      if (typeof snippet === 'string') {
        var target = LibraryManager.library[snippet];
        if (target) {
          // Redirection for aliases. We include the parent, and at runtime make ourselves equal to it.
          // This avoid having duplicate functions with identical content.
          redirectedIdent = snippet;
          deps.push(snippet);
          snippet = '_' + snippet;
        }
        // In asm, we need to know about library functions. If there is a target, though, then no
        // need to consider this a library function - we will call directly to it anyhow
        if (!redirectedIdent && (typeof target == 'function' || /Math_\w+/.exec(snippet))) {
          Functions.libraryFunctions[finalName] = 1;
        }
      } else if (typeof snippet === 'object') {
        snippet = stringifyWithFunctions(snippet);
      } else if (typeof snippet === 'function') {
        isFunction = true;
        snippet = processLibraryFunction(snippet, ident, finalName);
        Functions.libraryFunctions[finalName] = 1;
      }

      var postsetId = ident + '__postset';
      var postset = LibraryManager.library[postsetId];
      if (postset && !addedLibraryItems[postsetId] && !SIDE_MODULE) {
        addedLibraryItems[postsetId] = true;
        itemsDict.GlobalVariablePostSet.push({
          intertype: 'GlobalVariablePostSet',
          JS: postset + ';'
        });
      }

      if (redirectedIdent) {
        deps = deps.concat(LibraryManager.library[redirectedIdent + '__deps'] || []);
      }
      // In asm, dependencies implemented in C might be needed by JS library functions.
      // We don't know yet if they are implemented in C or not. To be safe, export such
      // special cases.
      [LIBRARY_DEPS_TO_AUTOEXPORT].forEach(function(special) {
        deps.forEach(function(dep) {
          if (dep == special && !EXPORTED_FUNCTIONS[dep]) {
            EXPORTED_FUNCTIONS[dep] = 1;
          }
        });
      });
      if (VERBOSE) printErr('adding ' + finalName + ' and deps ' + deps + ' : ' + (snippet + '').substr(0, 40));
      var depsText = (deps ? '\n' + deps.map(addFromLibrary).filter(function(x) { return x != '' }).join('\n') : '');
      var contentText;
      if (isFunction) {
        contentText = snippet;
      } else if (typeof snippet === 'string' && snippet.indexOf(';') == 0) {
        contentText = 'var ' + finalName + snippet;
        if (snippet[snippet.length-1] != ';' && snippet[snippet.length-1] != '}') contentText += ';';
      } else {
        contentText = 'var ' + finalName + '=' + snippet + ';';
      }
      var sig = LibraryManager.library[ident + '__sig'];
      if (isFunction && sig && LibraryManager.library[ident + '__asm']) {
        // asm library function, add it as generated code alongside the generated code
        Functions.implementedFunctions[finalName] = sig;
        asmLibraryFunctions.push(contentText);
        contentText = ' ';
        EXPORTED_FUNCTIONS[finalName] = 1;
        Functions.libraryFunctions[finalName] = 2;
      }
      if ((EXPORT_ALL || (finalName in EXPORTED_FUNCTIONS)) && !noExport) {
        contentText += '\nModule["' + finalName + '"] = ' + finalName + ';';
      }
      return depsText + contentText;
    }

    itemsDict.functionStub.push(item);
    var shortident = item.ident.substr(1);
    if (BUILD_AS_SHARED_LIB) {
      // Shared libraries reuse the runtime of their parents.
      item.JS = '';
    } else {
      // If this is not linkable, anything not in the library is definitely missing
      if (item.ident in DEAD_FUNCTIONS) {
        if (LibraryManager.library[shortident + '__asm']) {
          warn('cannot kill asm library function ' + item.ident);
        } else {
          LibraryManager.library[shortident] = new Function("Module['printErr']('dead function: " + shortident + "'); abort(-1);");
          delete LibraryManager.library[shortident + '__inline'];
          delete LibraryManager.library[shortident + '__deps'];
        }
      }
      item.JS = addFromLibrary(shortident);
    }
  }

  // Final combiner

  function finalCombiner() {
    var splitPostSets = splitter(itemsDict.GlobalVariablePostSet, function(x) { return x.ident && x.dependencies });
    itemsDict.GlobalVariablePostSet = splitPostSets.leftIn;
    var orderedPostSets = splitPostSets.splitOut;

    var limit = orderedPostSets.length * orderedPostSets.length;
    for (var i = 0; i < orderedPostSets.length; i++) {
      for (var j = i+1; j < orderedPostSets.length; j++) {
        if (orderedPostSets[j].ident in orderedPostSets[i].dependencies) {
          var temp = orderedPostSets[i];
          orderedPostSets[i] = orderedPostSets[j];
          orderedPostSets[j] = temp;
          i--;
          limit--;
          assert(limit > 0, 'Could not sort postsets!');
          break;
        }
      }
    }

    itemsDict.GlobalVariablePostSet = itemsDict.GlobalVariablePostSet.concat(orderedPostSets);

    //

    if (!mainPass) {
      if (!Variables.generatedGlobalBase && !BUILD_AS_SHARED_LIB) {
        Variables.generatedGlobalBase = true;
        // Globals are done, here is the rest of static memory
        if (!SIDE_MODULE) {
          print('STATIC_BASE = ' + Runtime.GLOBAL_BASE + ';\n');
          print('STATICTOP = STATIC_BASE + ' + Runtime.alignMemory(Variables.nextIndexedOffset) + ';\n');
        } else {
          print('gb = Runtime.alignMemory(getMemory({{{ STATIC_BUMP }}}, ' + MAX_GLOBAL_ALIGN + ' || 1));\n');
          print('// STATICTOP = STATIC_BASE + ' + Runtime.alignMemory(Variables.nextIndexedOffset) + ';\n'); // comment as metadata only
        }
        if (BINARYEN) {
          // export static base and bump, needed for linking in wasm binary's memory, dynamic linking, etc.
          print('var STATIC_BUMP = {{{ STATIC_BUMP }}};');
          print('Module["STATIC_BASE"] = STATIC_BASE;');
          print('Module["STATIC_BUMP"] = STATIC_BUMP;');
        }
      }
      var generated = itemsDict.function.concat(itemsDict.type).concat(itemsDict.GlobalVariableStub).concat(itemsDict.GlobalVariable);
      print(generated.map(function(item) { return item.JS; }).join('\n'));

      if (memoryInitialization.length > 0) {
        // apply postsets directly into the big memory initialization
        itemsDict.GlobalVariablePostSet = itemsDict.GlobalVariablePostSet.filter(function(item) {
          var m;
          if (m = /^HEAP([\dFU]+)\[([()>\d]+)\] *= *([()|\d{}\w_' ]+);?$/.exec(item.JS)) {
            var type = getTypeFromHeap(m[1]);
            var bytes = Runtime.getNativeTypeSize(type);
            var target = eval(m[2]) << log2(bytes);
            var value = m[3];
            try {
              value = eval(value);
            } catch(e) {
              // possibly function table {{{ FT_* }}} etc.
              if (value.indexOf('{{ ') < 0) return true;
            }
            writeInt8s(memoryInitialization, target - Runtime.GLOBAL_BASE, value, type);
            return false;
          }
          return true;
        });
        // write out the singleton big memory initialization value
        if (USE_PTHREADS) {
          print('if (!ENVIRONMENT_IS_PTHREAD) {') // Pthreads should not initialize memory again, since it's shared with the main thread.
        }
        print('/* memory initializer */ ' + makePointer(memoryInitialization, null, 'ALLOC_NONE', 'i8', 'Runtime.GLOBAL_BASE' + (SIDE_MODULE ? '+H_BASE' : ''), true));
        if (USE_PTHREADS) {
          print('}')
        }
      } else {
        print('/* no memory initializer */'); // test purposes
      }

      if (!BUILD_AS_SHARED_LIB && !SIDE_MODULE) {
        if (USE_PTHREADS) {
          print('var tempDoublePtr;\n');
          print('if (!ENVIRONMENT_IS_PTHREAD) tempDoublePtr = Runtime.alignMemory(allocate(12, "i8", ALLOC_STATIC), 8);\n');
        } else {
          print('var tempDoublePtr = ' + makeStaticAlloc(8) + '\n');
        }
        if (ASSERTIONS) print('assert(tempDoublePtr % 8 == 0);\n');
        print('function copyTempFloat(ptr) { // functions, because inlining this code increases code size too much\n');
        print('  HEAP8[tempDoublePtr] = HEAP8[ptr];\n');
        print('  HEAP8[tempDoublePtr+1] = HEAP8[ptr+1];\n');
        print('  HEAP8[tempDoublePtr+2] = HEAP8[ptr+2];\n');
        print('  HEAP8[tempDoublePtr+3] = HEAP8[ptr+3];\n');
        print('}\n');
        print('function copyTempDouble(ptr) {\n');
        print('  HEAP8[tempDoublePtr] = HEAP8[ptr];\n');
        print('  HEAP8[tempDoublePtr+1] = HEAP8[ptr+1];\n');
        print('  HEAP8[tempDoublePtr+2] = HEAP8[ptr+2];\n');
        print('  HEAP8[tempDoublePtr+3] = HEAP8[ptr+3];\n');
        print('  HEAP8[tempDoublePtr+4] = HEAP8[ptr+4];\n');
        print('  HEAP8[tempDoublePtr+5] = HEAP8[ptr+5];\n');
        print('  HEAP8[tempDoublePtr+6] = HEAP8[ptr+6];\n');
        print('  HEAP8[tempDoublePtr+7] = HEAP8[ptr+7];\n');
        print('}\n');
      }
      print('// {{PRE_LIBRARY}}\n'); // safe to put stuff here that statically allocates

      return;
    }

    // Print out global variables and postsets TODO: batching
    var legalizedI64sDefault = legalizedI64s;
    legalizedI64s = false;

    var globalsData = {functionStubs: []}
    JSify(globalsData, true);
    globalsData = null;

    var generated = itemsDict.functionStub.concat(itemsDict.GlobalVariablePostSet);
    generated.forEach(function(item) { print(indentify(item.JS || '', 2)); });

    legalizedI64s = legalizedI64sDefault;

    if (!BUILD_AS_SHARED_LIB && !SIDE_MODULE) {
      if (USE_PTHREADS) print('if (!ENVIRONMENT_IS_PTHREAD) {\n // Only main thread initializes these, pthreads copy them over at thread worker init time (in pthread-main.js)');
      print('DYNAMICTOP_PTR = allocate(1, "i32", ALLOC_STATIC);\n');
      print('STACK_BASE = STACKTOP = Runtime.alignMemory(STATICTOP);\n');
      if (STACK_START > 0) print('if (STACKTOP < ' + STACK_START + ') STACK_BASE = STACKTOP = Runtime.alignMemory(' + STACK_START + ');\n');
      print('STACK_MAX = STACK_BASE + TOTAL_STACK;\n');
      print('DYNAMIC_BASE = Runtime.alignMemory(STACK_MAX);\n');
      print('HEAP32[DYNAMICTOP_PTR>>2] = DYNAMIC_BASE;\n');
      print('staticSealed = true; // seal the static portion of memory\n');
      if (ASSERTIONS) print('assert(DYNAMIC_BASE < TOTAL_MEMORY, "TOTAL_MEMORY not big enough for stack");\n');
      if (USE_PTHREADS) print('}\n');
    }
    if (SPLIT_MEMORY) {
      print('assert(STACK_MAX < SPLIT_MEMORY, "SPLIT_MEMORY size must be big enough so the entire static memory + stack can fit in one chunk, need " + STACK_MAX);\n');
    }

    if (asmLibraryFunctions.length > 0) {
      print('// ASM_LIBRARY FUNCTIONS');
      function fix(f) { // fix indenting to not confuse js optimizer
        f = f.substr(f.indexOf('f')); // remove initial spaces before 'function'
        f = f.substr(0, f.lastIndexOf('\n')+1); // remove spaces and last }  XXX assumes function has multiple lines
        return f + '}'; // add unindented } to match function
      }
      print(asmLibraryFunctions.map(fix).join('\n'));
    }

    if (abortExecution) throw 'Aborting compilation due to previous errors';

    // This is the main 'post' pass. Print out the generated code that we have here, together with the
    // rest of the output that we started to print out earlier (see comment on the
    // "Final shape that will be created").
    print('// EMSCRIPTEN_END_FUNCS\n');

    if (HEADLESS) {
      print('if (!ENVIRONMENT_IS_WEB) {');
      print(read('headlessCanvas.js'));
      print('\n');
      print(read('headless.js').replace("'%s'", "'http://emscripten.org'").replace("'?%s'", "''").replace("'?%s'", "'/'").replace('%s,', 'null,').replace('%d', '0'));
      print('}');
    }
    if (PROXY_TO_WORKER) {
      print('if (ENVIRONMENT_IS_WORKER) {\n');
      print(read('webGLWorker.js'));
      print(processMacros(preprocess(read('proxyWorker.js'), 'proxyWorker.js')));
      print('}');
    }
    if (DETERMINISTIC) {
      print(read('deterministic.js'));
    }
    var postFile = BUILD_AS_SHARED_LIB || SIDE_MODULE ? 'postamble_sharedlib.js' : 'postamble.js';
    var postParts = processMacros(preprocess(read(postFile), postFile)).split('{{GLOBAL_VARS}}');
    print(postParts[0]);

    print(postParts[1]);

    var shellParts = read(shellFile).split('{{BODY}}');
    print(processMacros(preprocess(shellParts[1], shellFile)));
    // Print out some useful metadata
    if (RUNNING_JS_OPTS || PGO) {
      var generatedFunctions = JSON.stringify(keys(Functions.implementedFunctions));
      if (PGO) {
        print('PGOMonitor.allGenerated = ' + generatedFunctions + ';\nremoveRunDependency("pgo");\n');
      }
      if (RUNNING_JS_OPTS) {
        print('// EMSCRIPTEN_GENERATED_FUNCTIONS: ' + generatedFunctions + '\n');
      }
    }

    PassManager.serialize();
  }

  // Data

  if (mainPass) {
    data.functionStubs.forEach(functionStubHandler);
  }

  //B.start('jsifier-fc');
  finalCombiner();
  //B.stop('jsifier-fc');

  dprint('framework', 'Big picture: Finishing JSifier, main pass=' + mainPass);
  //B.stop('jsifier');
}