integrate eliminator as js optimizer pass

3 files changed, 0 insertions, 969 deletions

diff --git a/tools/eliminator.js b/tools/eliminator.js
deleted file mode 100644
index e6c9f808..00000000
--- a/tools/eliminator.js
+++ /dev/null
@@ -1,523 +0,0 @@
-/*
-  A script to eliminate redundant variables common in Emscripted code.
-
-  A variable === eliminateable if (it matches a leaf of that condition tree:
-
-  Single-def
-    Uses only side-effect-free nodes
-      Unused
-        *
-      Has at most MAX_USES uses
-        No mutations to any dependencies between def && last use
-          No global dependencies or no indirect accesses between def && use
-            *
-
-  TODO(max99x): Eliminate single-def undefined-initialized vars with no uses
-                between declaration && definition.
-*/
-
-// Imports.
-var uglify = require('../tools/eliminator/node_modules/uglify-js');
-var fs = require('fs');
-var os = require('os');
-
-function set() {
-  var args = typeof arguments[0] === 'object' ? arguments[0] : arguments;
-  var ret = {};
-  for (var i = 0; i < args.length; i++) {
-    ret[args[i]] = 0;
-  }
-  return ret;
-}
-
-// Functions which have been generated by Emscripten. We optimize only those.
-var generatedFunctions = {};
-var GENERATED_FUNCTIONS_MARKER = '// EMSCRIPTEN_GENERATED_FUNCTIONS:';
-function isGenerated (ident) {
-  return ident in generatedFunctions;
-}
-
-// Maximum number of uses to consider a variable not worth eliminating.
-// The risk with using > 1 === that a variable used by another can have
-// a chain that leads to exponential uses
-var MAX_USES = 1;
-
-// The UglifyJs code generator settings to use.
-var GEN_OPTIONS = {
-  ascii_only: true,
-  beautify: true,
-  indent_level: 2
-};
-
-// Node types which can be evaluated without side effects.
-var NODES_WITHOUT_SIDE_EFFECTS = {
-  name: true,
-  num: true,
-  string: true,
-  binary: true,
-  sub: true,
-  'unary-prefix': true // ++x can have side effects, but we never have that in generated code
-};
-
-// Nodes which may break control flow. Moving a variable beyond them may have
-// side effects.
-var CONTROL_FLOW_NODES = {
-  new: true,
-  throw: true,
-  call: true,
-  label: true,
-  debugger: true
-};
-
-var ANALYZE_BLOCK_TYPES = {
-  'switch': true,
-  'if': true,
-  'try': true,
-  'do': true,
-  'while': true,
-  'for': true,
-  'for-in': true
-};
-
-// Traverses a JavaScript syntax tree rooted at the given node calling the given
-// callback for each node.
-//   that.arg node: The root of the AST.
-//   that.arg callback: The callback to call for each node. This will be called with
-//     the node as the first argument && its type as the second. If false is
-//     returned, the traversal === stopped. If a non-undefined value === returned,
-//     it replaces the passed node in the tree.
-//   that.returns: If the root node was replaced, the new root node. If the traversal
-//     was stopped, false. Otherwise undefined.
-function traverse(node, callback) {
-  var type = node[0];
-  if (typeof type == 'string') {
-    result = callback(node, type);
-    if (result) return result;
-  }
-  for (var index = 0; index < node.length; index++) {
-    var subnode = node[index];
-    if (subnode && typeof subnode == 'object' && subnode.length) {
-      // NOTE: For-in nodes have unspecified var mutations. Skip them.
-      if (type == 'for-in' && subnode[0] == 'var') continue;
-      var subresult = traverse(subnode, callback);
-      if (subresult === false) {
-        return false;
-      } else if (subresult) {
-        node[index] = subresult;
-      }
-    }
-  }
-}
-
-// A class for eliminating redundant variables from JavaScript. Give it an AST
-// function/defun node && call run() to apply the optimization (in-place).
-var that = that; // there is always a single global Eliminator instance
-function Eliminator(func) {
-  that = this;
-  // The statements of the function to analyze.
-  this.body = func[3];
-
-  // Identifier stats. Each of these objects === indexed by the identifier name.
-  // Whether the identifier === a local variable.
-  this.isLocal = {};
-  // Whether the identifier === never modified after initialization.
-  this.isSingleDef = {};
-  // How many times the identifier === used.
-  this.useCount = {};
-  // Whether the initial value of a single-def identifier uses only nodes
-  // evaluating which has no side effects.
-  this.usesOnlySimpleNodes = {};
-  // Whether the identifier depends on any non-local name, perhaps indirectly.
-  this.dependsOnAGlobal = {};
-  // Whether the dependencies of the single-def identifier may be mutated
-  // within its live range.
-  this.depsMutatedInLiveRange = {};
-  // Maps a given single-def variable to the AST expression of its initial value.
-  this.initialValue = {};
-  // Maps identifiers to single-def variables which reference it in their
-  // initial value, i.e., which other variables it affects.
-  this.affects = {};
-
-  // Runs the eliminator on a given function body updating the AST in-place.
-  //   that.returns: The number of variables eliminated, or undefined if (skipped.
-  this.run = function() {
-    this.calculateBasicVarStats();
-    this.analyzeInitialValues();
-    this.calculateTransitiveDependencies();
-    this.analyzeLiveRanges();
-
-    var toReplace = {};
-    var eliminated = 0;
-    for (var varName in this.isSingleDef) {
-      if (this.isEliminateable(varName)) {
-        toReplace[varName] = this.initialValue[varName];
-        eliminated++;
-      }
-    }
-
-    this.removeDeclarations(toReplace);
-    this.collapseValues(toReplace);
-    this.updateUses(toReplace);
-
-    return eliminated;
-  };
-
-  // Runs the basic variable scan pass. Fills the following member variables:
-  //   isLocal
-  //   isSingleDef
-  //   useCount
-  //   initialValue
-  this.calculateBasicVarStats = function() {
-    traverse(this.body, function(node, type) {
-      if (type === 'var') {
-        var node1 = node[1];
-        for (var i = 0; i < node1.length; i++) {
-          var node1i = node1[i];
-          var varName = node1i[0];
-          var varValue = node1i[1];
-          that.isLocal[varName] = true;
-          if (!varValue) varValue = ['name', 'undefined']; // XXX share?
-          that.isSingleDef[varName] = !that.isSingleDef.hasOwnProperty(varName);
-          that.initialValue[varName] = varValue;
-          that.useCount[varName] = 0;
-        }
-      } else if (type === 'name') {
-        varName = node[1];
-        if (that.useCount.hasOwnProperty(varName)) that.useCount[varName]++;
-        else that.isSingleDef[varName] = false;
-      } else if (type == 'assign') {
-        varName = node[2][1];
-        if (that.isSingleDef[varName]) that.isSingleDef[varName] = false;
-      }
-    });
-  };
-
-  // Analyzes the initial values of single-def variables. Requires basic variable
-  // stats to have been calculated. Fills the following member variables:
-  //   affects
-  //   dependsOnAGlobal
-  //   usesOnlySimpleNodes
-  this.analyzeInitialValues = function() {
-    for (var varName in this.isSingleDef) {
-      if (!this.isSingleDef[varName]) continue;
-      this.usesOnlySimpleNodes[varName] = true;
-      traverse(this.initialValue[varName], function(node, type) {
-        if (!(type in NODES_WITHOUT_SIDE_EFFECTS)) {
-          that.usesOnlySimpleNodes[varName] = false;
-        } else if (type === 'name') {
-          var reference = node[1];
-          if (reference != 'undefined') {
-            if (!that.affects[reference]) that.affects[reference] = {};
-            if (!that.isLocal[reference]) that.dependsOnAGlobal[varName] = true;
-            that.affects[reference][varName] = true;
-          }
-        }
-      });
-    }
-  };
-
-  // Updates the dependency graph (@affects) to its transitive closure && 
-  // synchronizes this.dependsOnAGlobal to the new dependencies.
-  this.calculateTransitiveDependencies = function() {
-    var incomplete = true;
-    var todo = {};
-    for (var element in this.affects) {
-      todo[element] = 1;
-    }
-
-    //process.stdout.write 'pre ' + JSON.stringify(@affects, null, '  ') + '\n'
-
-    while (incomplete) {
-      incomplete = false;
-      var nextTodo = {};
-      for (var source in this.affects) {
-        var targets = this.affects[source];
-        for (var target in targets) {
-          if (todo[target]) {
-            var this_affects_target = this.affects[target];
-            for (target2 in this_affects_target) {
-              if (!targets[target2]) {
-                if (!this.isLocal[source]) this.dependsOnAGlobal[target2] = true;
-                targets[target2] = true;
-                nextTodo[source] = 1;
-                incomplete = true;
-              }
-            }
-          }
-        }
-      }
-      todo = nextTodo;
-    }
-
-    //process.stdout.write 'post ' + JSON.stringify(@affects, null, '  ') + '\n'
-  };
-
-  // Analyzes the live ranges of single-def variables. Requires dependencies to
-  // have been calculated. Fills the following member variables:
-  //   depsMutatedInLiveRange
-  this.analyzeLiveRanges = function() {
-    var isLive = {};
-
-    // Checks if (a given node may mutate any of the currently live variables.
-    function checkForMutations(node, type) {
-      var usedInThisStatement = {};
-      if (type == 'assign' || type == 'call') {
-        traverse(node.slice(2, 4), function(node, type) {
-          if (type === 'name') usedInThisStatement[node[1]] = true;
-        });
-      }
-
-      if (type == 'assign' || type == 'unary-prefix' || type == 'unary-postfix') {
-        if (type === 'assign' || node[1] == '--' || node[1] == '++') {
-          var reference = node[2];
-          while (reference[0] != 'name') {
-            reference = reference[1];
-          }
-          reference = reference[1];
-          var aff = that.affects[reference]
-          if (aff) {
-            for (var varName in aff) {
-              if (isLive[varName]) {
-                isLive[varName] = false;
-              }
-            }
-          }
-        }
-      }
-
-      if (type in CONTROL_FLOW_NODES) {
-        for (var varName in isLive) {
-          if (that.dependsOnAGlobal[varName] || !usedInThisStatement[varName]) {
-            isLive[varName] = false;
-          }
-        }
-      } else if (type === 'assign') {
-        for (var varName in isLive) {
-          if (that.dependsOnAGlobal[varName] && !usedInThisStatement[varName]) {
-            isLive[varName] = false;
-          }
-        }
-      } else if (type === 'name') {
-        var reference = node[1];
-        if (that.isSingleDef[reference]) {
-          if (!isLive[reference]) {
-            that.depsMutatedInLiveRange[reference] = true;
-          }
-        }
-      }
-    }
-
-    // Analyzes a block && all its children for variable ranges. Makes sure to
-    // account for the worst case of possible mutations.
-    function analyzeBlock(node, type) {
-      if (type in ANALYZE_BLOCK_TYPES) {
-        function traverseChild(child) {
-          if (child && typeof child == 'object' && child.length) {
-            var savedLive = {};
-            for (var name in isLive) savedLive[name] = true;
-            traverse(child, analyzeBlock);
-            for (var name in isLive) {
-              if (!isLive[name]) savedLive[name] = false;
-            }
-            isLive = savedLive;
-          }
-        }
-        if (type === 'switch') {
-          traverseChild(node[1]);
-          var node2 = node[2];
-          for (var i = 0; i < node2.length; i++) {
-            traverseChild(node2[i]);
-          }
-        } else if (type == 'if' || type == 'try') {
-          for (var i = 0; i < node.length; i++) {
-            traverseChild(node[i]);
-          }
-        } else {
-          // Don't put anything from outside into the body of a loop.
-          isLive = {};
-          node.forEach(traverseChild);
-          // Don't keep anything alive through a loop
-          isLive = {};
-        }
-        return node;
-      }  else if (type === 'var') {
-        var node1 = node[1];
-        for (var i = 0; i < node1.length; i++) {
-          var node1i = node1[i];
-          var varName = node1i[0];
-          var varValue = node1i[1];
-          if (varValue) traverse(varValue, checkForMutations);
-          // Mark the variable as live
-          if (that.isSingleDef[varName]) {
-            isLive[varName] = true;
-          }
-          // Mark variables that depend on it as no longer live
-          if (that.affects[varName]) {
-            var aff = that.affects[varName];
-            for (var varNameDep in aff) {
-              if (isLive[varNameDep]) {
-                isLive[varNameDep] = false;
-              }
-            }
-          }
-        }
-        return node;
-      } else {
-        checkForMutations(node, type);
-      }
-    }
-
-    traverse(this.body, analyzeBlock);
-  };
-
-  // Determines whether a given variable can be safely eliminated. Requires all
-  // analysis passes to have been run.
-  this.isEliminateable = function(varName) {
-    if (this.isSingleDef[varName] && this.usesOnlySimpleNodes[varName]) {
-      if (this.useCount[varName] == 0) {
-        return true;
-      } else if (this.useCount[varName] <= MAX_USES) {
-        return !this.depsMutatedInLiveRange[varName];
-      }
-    }
-    return false;
-  };
-
-  // Removes all var declarations for the specified variables.
-  //   this.arg toRemove: An object whose keys are the variable names to remove.
-  this.removeDeclarations = function(toRemove) {
-    traverse(this.body, function(node, type) {
-      if (type === 'var') {
-        var intactVars = node[1].filter(function(i) { return !toRemove.hasOwnProperty(i[0]) });
-        if (intactVars.length) {
-          node[1] = intactVars;
-          return node;
-        } else {
-          return ['toplevel', []];
-        }
-      }
-    });
-  };
-
-  // Updates all the values for the given variables to eliminate reference to any
-  // of the other variables in the group.
-  //   this.arg values: A map from variable names to their values as AST expressions.
-  this.collapseValues = function(values) {
-    var incomplete = true;
-    while (incomplete) {
-      incomplete = false;
-      for (var varName in values) {
-        var varValue = values[varName];
-        var result = traverse(varValue, function(node, type) {
-          if (type == 'name' && values.hasOwnProperty(node[1]) && node[1] != varName) {
-            incomplete = true;
-            return values[node[1]];
-          }
-        });
-        if (result) values[varName] = result;
-      }
-    }
-  };
-
-  // Replaces all uses of the specified variables with their respective
-  // expressions.
-  //   this.arg replacements: A map from variable names to AST expressions.
-  this.updateUses = function(replacements) {
-    traverse(this.body, function(node, type) {
-      if (type === 'name' && replacements.hasOwnProperty(node[1])) {
-        return replacements[node[1]];
-      }
-    });
-  };
-}
-
-// A class for optimizing expressions. We know that it === legitimate to collapse
-// 5+7 in the generated code, as it will always be numerical, for example. XXX do we need this? here?
-function ExpressionOptimizer(node) {
-  this.node = node;
-
-  this.run = function() {
-    traverse(this.node, function(node, type) {
-      if (type === 'binary' && node[1] == '+') {
-        var names = [];
-        var num = 0;
-        var has_num = false;
-        var fail = false;
-        traverse(node, function(subNode, subType) {
-          if (subType === 'binary') {
-            if (subNode[1] != '+') {
-              fail = true;
-              return false;
-            }
-          } else if (subType === 'name') {
-            names.push(subNode[1]);
-            return;
-          } else if (subType === 'num') {
-            num += subNode[1];
-            has_num = true;
-            return;
-          } else {
-            fail = true;
-            return false;
-          }
-        });
-        if (!fail && has_num) {
-          var ret = ['num', num];
-          for (var i = 0; i < names.length; i++) {
-            ret = ['binary', '+', ['name', names[i]], ret];
-          }
-          return ret;
-        }
-      }
-    });
-  };
-}
-
-// The main entry point. Reads JavaScript from stdin, runs the eliminator on each
-// function, then writes the optimized result to stdout.
-function main() {
-  // Get the parse tree.
-  //process.stderr.write(JSON.stringify(process.argv[2]) + '\n')
-  var src = fs.readFileSync(process.argv[2]).toString();
-
-  var generatedFunctionsLine = src.split('\n').filter(function(line) {
-    return line.indexOf(GENERATED_FUNCTIONS_MARKER) == 0;
-  });
-  generatedFunctions = set(eval(generatedFunctionsLine[0].replace(GENERATED_FUNCTIONS_MARKER, '')));
-
-  var ast = uglify.parser.parse(src);
-
-  //process.stderr.write('1 ' + JSON.stringify(ast, null, 2) + '\n')
-
-  // Run on all functions.
-  traverse(ast, function(node, type) {
-    if ((type == 'defun' || type == 'function') && isGenerated(node[1])) {
-      // Run the eliminator
-      //process.stderr.write (node[1] || '(anonymous)') + '\n'
-      var eliminated = new Eliminator(node).run();
-      // Run the expression optimizer
-      new ExpressionOptimizer(node[3]).run();
-    }
-  });
-
-  // Write out the optimized code.
-  // NOTE: For large file, can't generate code for the whole file in a single
-  //       call due to the v8 memory limit. Writing out root children instead.
-  var ast1 = ast[1];
-  for (var i = 0; i < ast1.length; i++) {
-    var node = ast1[i];
-
-    var js = uglify.uglify.gen_code(node, GEN_OPTIONS), old;
-    // remove unneeded newlines+spaces
-    do {
-      old = js;
-      js = js.replace(/\n *\n/g, '\n');
-    } while (js != old);
-    process.stdout.write(js);
-    process.stdout.write('\n');
-  }
-  process.stdout.write(generatedFunctionsLine + '\n');
-}
-
-main();
-
diff --git a/tools/eliminator/eliminator.coffee b/tools/eliminator/eliminator.coffee
deleted file mode 100644
index 05e3788b..00000000
--- a/tools/eliminator/eliminator.coffee
+++ /dev/null
@@ -1,429 +0,0 @@
-###
-  A script to eliminate redundant variables common in Emscripted code.
-
-  A variable is eliminateable if it matches a leaf of this condition tree:
-
-  Single-def
-    Uses only side-effect-free nodes
-      Unused
-        *
-      Has at most MAX_USES uses
-        No mutations to any dependencies between def and last use
-          No global dependencies or no indirect accesses between def and use
-            *
-
-  TODO(max99x): Eliminate single-def undefined-initialized vars with no uses
-                between declaration and definition.
-###
-
-# Imports.
-uglify = require 'uglify-js'
-fs = require 'fs'
-os = require 'os'
-
-# Functions which have been generated by Emscripten. We optimize only those.
-generatedFunctions = []
-GENERATED_FUNCTIONS_MARKER = '// EMSCRIPTEN_GENERATED_FUNCTIONS:'
-isGenerated = (ident) ->
-  ident in generatedFunctions
-
-# Maximum number of uses to consider a variable not worth eliminating.
-# The risk with using > 1 is that a variable used by another can have
-# a chain that leads to exponential uses
-MAX_USES = 1
-
-# The UglifyJs code generator settings to use.
-GEN_OPTIONS =
-  ascii_only: true
-  beautify: true
-  indent_level: 2
-
-# Node types which can be evaluated without side effects.
-NODES_WITHOUT_SIDE_EFFECTS =
-  name: true
-  num: true
-  string: true
-  binary: true
-  sub: true
-  'unary-prefix': true # ++x can have side effects, but we never have that in generated code
-
-# Nodes which may break control flow. Moving a variable beyond them may have
-# side effects.
-CONTROL_FLOW_NODES =
-  new: true
-  throw: true
-  call: true
-  label: true
-  debugger: true
-
-# Traverses a JavaScript syntax tree rooted at the given node calling the given
-# callback for each node.
-#   @arg node: The root of the AST.
-#   @arg callback: The callback to call for each node. This will be called with
-#     the node as the first argument and its type as the second. If false is
-#     returned, the traversal is stopped. If a non-undefined value is returned,
-#     it replaces the passed node in the tree.
-#   @returns: If the root node was replaced, the new root node. If the traversal
-#     was stopped, false. Otherwise undefined.
-traverse = (node, callback) ->
-  type = node[0]
-  if typeof type == 'string'
-    result = callback node, type
-    if result? then return result
-
-  for subnode, index in node
-    if typeof subnode is 'object' and subnode?.length
-      # NOTE: For-in nodes have unspecified var mutations. Skip them.
-      if type == 'for-in' and subnode?[0] == 'var' then continue
-      subresult = traverse subnode, callback
-      if subresult is false
-        return false
-      else if subresult?
-        node[index] = subresult
-  return undefined
-
-# A class for eliminating redundant variables from JavaScript. Give it an AST
-# function/defun node and call run() to apply the optimization (in-place).
-class Eliminator
-  constructor: (func) ->
-    # The statements of the function to analyze.
-    @body = func[3]
-
-    # Identifier stats. Each of these objects is indexed by the identifier name.
-    # Whether the identifier is a local variable.
-    @isLocal = {}
-    # Whether the identifier is never modified after initialization.
-    @isSingleDef = {}
-    # How many times the identifier is used.
-    @useCount = {}
-    # Whether the initial value of a single-def identifier uses only nodes
-    # evaluating which has no side effects.
-    @usesOnlySimpleNodes = {}
-    # Whether the identifier depends on any non-local name, perhaps indirectly.
-    @dependsOnAGlobal = {}
-    # Whether the dependencies of the single-def identifier may be mutated
-    # within its live range.
-    @depsMutatedInLiveRange = {}
-    # Maps a given single-def variable to the AST expression of its initial value.
-    @initialValue = {}
-    # Maps identifiers to single-def variables which reference it in their
-    # initial value, i.e., which other variables it affects.
-    @affects = {}
-
-  # Runs the eliminator on a given function body updating the AST in-place.
-  #   @returns: The number of variables eliminated, or undefined if skipped.
-  run: ->
-    @calculateBasicVarStats()
-    @analyzeInitialValues()
-    @calculateTransitiveDependencies()
-    @analyzeLiveRanges()
-
-    toReplace = {}
-    eliminated = 0
-    for varName of @isSingleDef
-      if @isEliminateable varName
-        toReplace[varName] = @initialValue[varName]
-        eliminated++
-
-    @removeDeclarations toReplace
-    @collapseValues toReplace
-    @updateUses toReplace
-
-    return eliminated
-
-  # Runs the basic variable scan pass. Fills the following member variables:
-  #   isLocal
-  #   isSingleDef
-  #   useCount
-  #   initialValue
-  calculateBasicVarStats: ->
-    traverse @body, (node, type) =>
-      if type is 'var'
-        for [varName, varValue] in node[1]
-          @isLocal[varName] = true
-          if not varValue? then varValue = ['name', 'undefined']
-          @isSingleDef[varName] = not @isSingleDef.hasOwnProperty varName
-          @initialValue[varName] = varValue
-          @useCount[varName] = 0
-      else if type is 'name'
-        varName = node[1]
-        if @useCount.hasOwnProperty varName then @useCount[varName]++
-        else @isSingleDef[varName] = false
-      else if type in ['assign']
-        varName = node[2][1]
-        if @isSingleDef[varName] then @isSingleDef[varName] = false
-      return undefined
-    return undefined
-
-  # Analyzes the initial values of single-def variables. Requires basic variable
-  # stats to have been calculated. Fills the following member variables:
-  #   affects
-  #   dependsOnAGlobal
-  #   usesOnlySimpleNodes
-  analyzeInitialValues: ->
-    for varName of @isSingleDef
-      if not @isSingleDef[varName] then continue
-      @usesOnlySimpleNodes[varName] = true
-      traverse @initialValue[varName], (node, type) =>
-        if type not of NODES_WITHOUT_SIDE_EFFECTS
-          @usesOnlySimpleNodes[varName] = false
-        else if type is 'name'
-          reference = node[1]
-          if reference != 'undefined'
-            if not @affects[reference]? then @affects[reference] = {}
-            if not @isLocal[reference] then @dependsOnAGlobal[varName] = true
-            @affects[reference][varName] = true
-        return undefined
-    return undefined
-
-  # Updates the dependency graph (@affects) to its transitive closure and 
-  # synchronizes @dependsOnAGlobal to the new dependencies.
-  calculateTransitiveDependencies: ->
-    incomplete = true
-    todo = {}
-    for element of @affects
-      todo[element] = 1
-
-    #process.stdout.write 'pre ' + JSON.stringify(@affects, null, '  ') + '\n'
-
-    while incomplete
-      incomplete = false
-      nextTodo = {}
-      for source, targets of @affects
-        for target of targets
-          if todo[target]
-            for target2 of @affects[target]
-              if not targets[target2]
-                if not @isLocal[source] then @dependsOnAGlobal[target2] = true
-                targets[target2] = true
-                nextTodo[source] = 1
-                incomplete = true
-      todo = nextTodo
-
-    #process.stdout.write 'post ' + JSON.stringify(@affects, null, '  ') + '\n'
-
-    return undefined
-
-  # Analyzes the live ranges of single-def variables. Requires dependencies to
-  # have been calculated. Fills the following member variables:
-  #   depsMutatedInLiveRange
-  analyzeLiveRanges: ->
-    isLive = {}
-
-    # Checks if a given node may mutate any of the currently live variables.
-    checkForMutations = (node, type) =>
-      usedInThisStatement = {}
-      if type in ['assign', 'call']
-        traverse node.slice(2, 4), (node, type) =>
-          if type is 'name' then usedInThisStatement[node[1]] = true
-          return undefined
-
-      if type in ['assign', 'unary-prefix', 'unary-postfix']
-        if type is 'assign' or node[1] in ['--', '++']
-          reference = node[2]
-          while reference[0] != 'name'
-            reference = reference[1]
-          reference = reference[1]
-          if @affects[reference]?
-            for varName of @affects[reference]
-              if isLive[varName]
-                isLive[varName] = false
-
-      if type of CONTROL_FLOW_NODES
-        for varName of isLive
-          if @dependsOnAGlobal[varName] or not usedInThisStatement[varName]
-            isLive[varName] = false
-      else if type is 'assign'
-        for varName of isLive
-          if @dependsOnAGlobal[varName] and not usedInThisStatement[varName]
-            isLive[varName] = false
-      else if type is 'name'
-        reference = node[1]
-        if @isSingleDef[reference]
-          if not isLive[reference]
-            @depsMutatedInLiveRange[reference] = true
-      return undefined
-
-    # Analyzes a block and all its children for variable ranges. Makes sure to
-    # account for the worst case of possible mutations.
-    analyzeBlock = (node, type) =>
-      if type in ['switch', 'if', 'try', 'do', 'while', 'for', 'for-in']
-        traverseChild = (child) ->
-          if typeof child == 'object' and child?.length
-            savedLive = {}
-            for name of isLive then savedLive[name] = true
-            traverse child, analyzeBlock
-            for name of isLive
-              if not isLive[name] then savedLive[name] = false
-            isLive = savedLive
-        if type is 'switch'
-          traverseChild node[1]
-          for child in node[2]
-            traverseChild child
-        else if type in ['if', 'try']
-          for child in node
-            traverseChild child
-        else
-          # Don't put anything from outside into the body of a loop.
-          isLive = {}
-          for child in node then traverseChild child
-          # Don't keep anything alive through a loop
-          isLive = {}
-        return node
-      else if type is 'var'
-        for [varName, varValue] in node[1]
-          if varValue? then traverse varValue, checkForMutations
-          # Mark the variable as live
-          if @isSingleDef[varName]
-            isLive[varName] = true
-          # Mark variables that depend on it as no longer live
-          if @affects[varName]?
-            for varNameDep of @affects[varName]
-              if isLive[varNameDep]
-                isLive[varNameDep] = false
-        return node
-      else
-        checkForMutations node, type
-      return undefined
-
-    traverse @body, analyzeBlock
-
-    return undefined
-
-  # Determines whether a given variable can be safely eliminated. Requires all
-  # analysis passes to have been run.
-  isEliminateable: (varName) ->
-    if @isSingleDef[varName] and @usesOnlySimpleNodes[varName]
-      if @useCount[varName] == 0
-        return true
-      else if @useCount[varName] <= MAX_USES
-        return not @depsMutatedInLiveRange[varName]
-    return false
-
-  # Removes all var declarations for the specified variables.
-  #   @arg toRemove: An object whose keys are the variable names to remove.
-  removeDeclarations: (toRemove) ->
-    traverse @body, (node, type) ->
-      if type is 'var'
-        intactVars = (i for i in node[1] when not toRemove.hasOwnProperty i[0])
-        if intactVars.length
-          node[1] = intactVars
-          return node
-        else
-          return ['toplevel', []]
-      return undefined
-    return undefined
-
-  # Updates all the values for the given variables to eliminate reference to any
-  # of the other variables in the group.
-  #   @arg values: A map from variable names to their values as AST expressions.
-  collapseValues: (values) ->
-    incomplete = true
-    while incomplete
-      incomplete = false
-      for varName, varValue of values
-        result = traverse varValue, (node, type) ->
-          if type == 'name' and values.hasOwnProperty(node[1]) and node[1] != varName
-            incomplete = true
-            return values[node[1]]
-          return undefined
-        if result? then values[varName] = result
-    return undefined
-
-  # Replaces all uses of the specified variables with their respective
-  # expressions.
-  #   @arg replacements: A map from variable names to AST expressions.
-  updateUses: (replacements) ->
-    traverse @body, (node, type) ->
-      if type is 'name' and replacements.hasOwnProperty node[1]
-        return replacements[node[1]]
-      return undefined
-    return undefined
-
-
-# A class for optimizing expressions. We know that it is legitimate to collapse
-# 5+7 in the generated code, as it will always be numerical, for example.
-class ExpressionOptimizer
-  constructor: (node) ->
-    @node = node
-
-  run: ->
-    traverse @node, (node, type) ->
-      if type is 'binary' and node[1] == '+'
-        names = []
-        num = 0
-        has_num = false
-        fail = false
-        traverse node, (subNode, subType) ->
-          if subType is 'binary'
-            if subNode[1] isnt '+'
-              fail = true
-              return false
-            return undefined
-          else if subType is 'name'
-            names.push subNode[1]
-            return undefined
-          else if subType is 'num'
-            num += subNode[1]
-            has_num = true
-            return undefined
-          else
-            fail = true
-            return false
-        if not fail and has_num
-          ret = ['num', num]
-          for name in names
-            ret = ['binary', '+', ['name', name], ret]
-          return ret
-        return undefined
-          
-      return undefined
-
-# The main entry point. Reads JavaScript from stdin, runs the eliminator on each
-# function, then writes the optimized result to stdout.
-main = ->
-  # Get the parse tree.
-  #process.stderr.write(JSON.stringify(process.argv[2]) + '\n')
-  src = fs.readFileSync(process.argv[2]).toString()
-
-  throw 'Cannot identify generated functions' if GENERATED_FUNCTIONS_MARKER in src
-  generatedFunctionsLine = src.split('\n').filter (line) ->
-    return line.indexOf(GENERATED_FUNCTIONS_MARKER) == 0
-  generatedFunctions = eval(generatedFunctionsLine[0].replace(GENERATED_FUNCTIONS_MARKER, ''))
-
-  ast = uglify.parser.parse src
-
-  ##process.stderr.write(JSON.stringify(ast) + '\n')
-
-  # Run on all functions.
-  traverse ast, (node, type) ->
-    if type in ['defun', 'function'] and isGenerated node[1]
-
-      # Run the eliminator
-      #process.stderr.write (node[1] || '(anonymous)') + '\n'
-      eliminated = new Eliminator(node).run()
-      if eliminated?
-        #process.stderr.write "  Eliminated #{eliminated} vars.\n"
-
-        # Run the expression optimizer
-        new ExpressionOptimizer(node[3]).run()
-      else
-        #process.stderr.write '  Skipped.\n'
-
-    return undefined
-
-  # Write out the optimized code.
-  # NOTE: For large file, can't generate code for the whole file in a single
-  #       call due to the v8 memory limit. Writing out root children instead.
-  for node in ast[1]
-    # Parse and recompile again, to remove unneeded lines
-    src2 = uglify.uglify.gen_code node, GEN_OPTIONS
-    node2 = uglify.parser.parse src2
-
-    process.stdout.write uglify.uglify.gen_code node2, GEN_OPTIONS
-    process.stdout.write '\n'
-  process.stdout.write generatedFunctionsLine + '\n'
-
-  return undefined
-
-main()
diff --git a/tools/shared.py b/tools/shared.py
index 84ce6c2e..6150060b 100644
--- a/tools/shared.py
+++ b/tools/shared.py
@@ -190,7 +190,6 @@ LLVM_NM=os.path.expanduser(build_llvm_tool_path('llvm-nm'))
 LLVM_INTERPRETER=os.path.expanduser(build_llvm_tool_path('lli'))
 LLVM_COMPILER=os.path.expanduser(build_llvm_tool_path('llc'))
 LLVM_EXTRACT=os.path.expanduser(build_llvm_tool_path('llvm-extract'))
-COFFEESCRIPT = path_from_root('tools', 'eliminator', 'node_modules', 'coffee-script', 'bin', 'coffee')
 
 EMSCRIPTEN = path_from_root('emscripten.py')
 DEMANGLER = path_from_root('third_party', 'demangler.py')
@@ -205,7 +204,6 @@ EMMAKEN = path_from_root('tools', 'emmaken.py')
 AUTODEBUGGER = path_from_root('tools', 'autodebugger.py')
 BINDINGS_GENERATOR = path_from_root('tools', 'bindings_generator.py')
 EXEC_LLVM = path_from_root('tools', 'exec_llvm.py')
-VARIABLE_ELIMINATOR = path_from_root('tools', 'eliminator.js')
 JS_OPTIMIZER = path_from_root('tools', 'js-optimizer.js')
 FILE_PACKAGER = path_from_root('tools', 'file_packager.py')
 
@@ -988,21 +986,6 @@ set(CMAKE_FIND_ROOT_PATH_MODE_PACKAGE ONLY)''' % { 'winfix': '' if not WINDOWS e
     return filename
 
   @staticmethod
-  def eliminator(filename, maybe_big=True):
-    if maybe_big:
-      ret = Building.splitter(filename, addendum='.el.js', func=Building.eliminator)
-      if ret: return ret
-
-    input = open(filename, 'r').read()
-    output = Popen([NODE_JS, VARIABLE_ELIMINATOR, filename], stdout=PIPE).communicate()[0]
-    assert len(output) > 0, 'Error in eliminator: ' + output
-    filename += '.el.js'
-    f = open(filename, 'w')
-    f.write(output)
-    f.close()
-    return filename
-
-  @staticmethod
   def closure_compiler(filename):
     if not os.path.exists(CLOSURE_COMPILER):
       raise Exception('Closure compiler appears to be missing, looked at: ' + str(CLOSURE_COMPILER))