import full versions of dependency libraries!

1 files changed, 946 insertions, 0 deletions

diff --git a/deps/v8/src/scopes.cc b/deps/v8/src/scopes.cc
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+// Copyright 2006-2008 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+//       notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+//       copyright notice, this list of conditions and the following
+//       disclaimer in the documentation and/or other materials provided
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#include "v8.h"
+
+#include "prettyprinter.h"
+#include "scopeinfo.h"
+#include "scopes.h"
+
+namespace v8 { namespace internal {
+
+// ----------------------------------------------------------------------------
+// A Zone allocator for use with LocalsMap.
+
+class ZoneAllocator: public Allocator {
+ public:
+  /* nothing to do */
+  virtual ~ZoneAllocator()  {}
+
+  virtual void* New(size_t size)  { return Zone::New(size); }
+
+  /* ignored - Zone is freed in one fell swoop */
+  virtual void Delete(void* p)  {}
+};
+
+
+static ZoneAllocator LocalsMapAllocator;
+
+
+// ----------------------------------------------------------------------------
+// Implementation of LocalsMap
+//
+// Note: We are storing the handle locations as key values in the hash map.
+//       When inserting a new variable via Declare(), we rely on the fact that
+//       the handle location remains alive for the duration of that variable
+//       use. Because a Variable holding a handle with the same location exists
+//       this is ensured.
+
+static bool Match(void* key1, void* key2) {
+  String* name1 = *reinterpret_cast<String**>(key1);
+  String* name2 = *reinterpret_cast<String**>(key2);
+  ASSERT(name1->IsSymbol());
+  ASSERT(name2->IsSymbol());
+  return name1 == name2;
+}
+
+
+// Dummy constructor
+LocalsMap::LocalsMap(bool gotta_love_static_overloading) : HashMap()  {}
+
+LocalsMap::LocalsMap() : HashMap(Match, &LocalsMapAllocator, 8)  {}
+LocalsMap::~LocalsMap()  {}
+
+
+Variable* LocalsMap::Declare(Scope* scope,
+                             Handle<String> name,
+                             Variable::Mode mode,
+                             bool is_valid_LHS,
+                             bool is_this) {
+  HashMap::Entry* p = HashMap::Lookup(name.location(), name->Hash(), true);
+  if (p->value == NULL) {
+    // The variable has not been declared yet -> insert it.
+    ASSERT(p->key == name.location());
+    p->value = new Variable(scope, name, mode, is_valid_LHS, is_this);
+  }
+  return reinterpret_cast<Variable*>(p->value);
+}
+
+
+Variable* LocalsMap::Lookup(Handle<String> name) {
+  HashMap::Entry* p = HashMap::Lookup(name.location(), name->Hash(), false);
+  if (p != NULL) {
+    ASSERT(*reinterpret_cast<String**>(p->key) == *name);
+    ASSERT(p->value != NULL);
+    return reinterpret_cast<Variable*>(p->value);
+  }
+  return NULL;
+}
+
+
+// ----------------------------------------------------------------------------
+// Implementation of Scope
+
+
+// Dummy constructor
+Scope::Scope()
+  : inner_scopes_(0),
+    locals_(false),
+    temps_(0),
+    params_(0),
+    nonlocals_(0),
+    unresolved_(0),
+    decls_(0) {
+}
+
+
+Scope::Scope(Scope* outer_scope, Type type)
+  : outer_scope_(outer_scope),
+    inner_scopes_(4),
+    type_(type),
+    scope_name_(Factory::empty_symbol()),
+    locals_(),
+    temps_(4),
+    params_(4),
+    nonlocals_(4),
+    unresolved_(16),
+    decls_(4),
+    receiver_(NULL),
+    function_(NULL),
+    arguments_(NULL),
+    arguments_shadow_(NULL),
+    illegal_redecl_(NULL),
+    scope_inside_with_(false),
+    scope_contains_with_(false),
+    scope_calls_eval_(false),
+    outer_scope_calls_eval_(false),
+    inner_scope_calls_eval_(false),
+    outer_scope_is_eval_scope_(false),
+    force_eager_compilation_(false),
+    num_stack_slots_(0),
+    num_heap_slots_(0) {
+  // At some point we might want to provide outer scopes to
+  // eval scopes (by walking the stack and reading the scope info).
+  // In that case, the ASSERT below needs to be adjusted.
+  ASSERT((type == GLOBAL_SCOPE || type == EVAL_SCOPE) == (outer_scope == NULL));
+  ASSERT(!HasIllegalRedeclaration());
+}
+
+
+void Scope::Initialize(bool inside_with) {
+  // Add this scope as a new inner scope of the outer scope.
+  if (outer_scope_ != NULL) {
+    outer_scope_->inner_scopes_.Add(this);
+    scope_inside_with_ = outer_scope_->scope_inside_with_ || inside_with;
+  } else {
+    scope_inside_with_ = inside_with;
+  }
+
+  // Declare convenience variables.
+  // Declare and allocate receiver (even for the global scope, and even
+  // if naccesses_ == 0).
+  // NOTE: When loading parameters in the global scope, we must take
+  // care not to access them as properties of the global object, but
+  // instead load them directly from the stack. Currently, the only
+  // such parameter is 'this' which is passed on the stack when
+  // invoking scripts
+  { Variable* var =
+      locals_.Declare(this, Factory::this_symbol(), Variable::VAR, false, true);
+    var->rewrite_ = new Slot(var, Slot::PARAMETER, -1);
+    receiver_ = new VariableProxy(Factory::this_symbol(), true, false);
+    receiver_->BindTo(var);
+  }
+
+  if (is_function_scope()) {
+    // Declare 'arguments' variable which exists in all functions.
+    // Note that it may never be accessed, in which case it won't
+    // be allocated during variable allocation.
+    Declare(Factory::arguments_symbol(), Variable::VAR);
+  }
+}
+
+
+
+Variable* Scope::LookupLocal(Handle<String> name) {
+  return locals_.Lookup(name);
+}
+
+
+Variable* Scope::Lookup(Handle<String> name) {
+  for (Scope* scope = this;
+       scope != NULL;
+       scope = scope->outer_scope()) {
+    Variable* var = scope->LookupLocal(name);
+    if (var != NULL) return var;
+  }
+  return NULL;
+}
+
+
+Variable* Scope::DeclareFunctionVar(Handle<String> name) {
+  ASSERT(is_function_scope() && function_ == NULL);
+  function_ = new Variable(this, name, Variable::CONST, true, false);
+  return function_;
+}
+
+
+Variable* Scope::Declare(Handle<String> name, Variable::Mode mode) {
+  // DYNAMIC variables are introduces during variable allocation,
+  // INTERNAL variables are allocated explicitly, and TEMPORARY
+  // variables are allocated via NewTemporary().
+  ASSERT(mode == Variable::VAR || mode == Variable::CONST);
+  return locals_.Declare(this, name, mode, true, false);
+}
+
+
+void Scope::AddParameter(Variable* var) {
+  ASSERT(is_function_scope());
+  ASSERT(LookupLocal(var->name()) == var);
+  params_.Add(var);
+}
+
+
+VariableProxy* Scope::NewUnresolved(Handle<String> name, bool inside_with) {
+  // Note that we must not share the unresolved variables with
+  // the same name because they may be removed selectively via
+  // RemoveUnresolved().
+  VariableProxy* proxy = new VariableProxy(name, false, inside_with);
+  unresolved_.Add(proxy);
+  return proxy;
+}
+
+
+void Scope::RemoveUnresolved(VariableProxy* var) {
+  // Most likely (always?) any variable we want to remove
+  // was just added before, so we search backwards.
+  for (int i = unresolved_.length(); i-- > 0;) {
+    if (unresolved_[i] == var) {
+      unresolved_.Remove(i);
+      return;
+    }
+  }
+}
+
+
+VariableProxy* Scope::NewTemporary(Handle<String> name) {
+  Variable* var = new Variable(this, name, Variable::TEMPORARY, true, false);
+  VariableProxy* tmp = new VariableProxy(name, false, false);
+  tmp->BindTo(var);
+  temps_.Add(var);
+  return tmp;
+}
+
+
+void Scope::AddDeclaration(Declaration* declaration) {
+  decls_.Add(declaration);
+}
+
+
+void Scope::SetIllegalRedeclaration(Expression* expression) {
+  // Only set the illegal redeclaration expression the
+  // first time the function is called.
+  if (!HasIllegalRedeclaration()) {
+    illegal_redecl_ = expression;
+  }
+  ASSERT(HasIllegalRedeclaration());
+}
+
+
+void Scope::VisitIllegalRedeclaration(AstVisitor* visitor) {
+  ASSERT(HasIllegalRedeclaration());
+  illegal_redecl_->Accept(visitor);
+}
+
+
+template<class Allocator>
+void Scope::CollectUsedVariables(List<Variable*, Allocator>* locals) {
+  // Collect variables in this scope.
+  // Note that the function_ variable - if present - is not
+  // collected here but handled separately in ScopeInfo
+  // which is the current user of this function).
+  for (int i = 0; i < temps_.length(); i++) {
+    Variable* var = temps_[i];
+    if (var->var_uses()->is_used()) {
+      locals->Add(var);
+    }
+  }
+  for (LocalsMap::Entry* p = locals_.Start(); p != NULL; p = locals_.Next(p)) {
+    Variable* var = reinterpret_cast<Variable*>(p->value);
+    if (var->var_uses()->is_used()) {
+      locals->Add(var);
+    }
+  }
+}
+
+
+// Make sure the method gets instantiated by the template system.
+template void Scope::CollectUsedVariables(
+    List<Variable*, FreeStoreAllocationPolicy>* locals);
+template void Scope::CollectUsedVariables(
+    List<Variable*, PreallocatedStorage>* locals);
+
+
+void Scope::AllocateVariables(Handle<Context> context) {
+  ASSERT(outer_scope_ == NULL);  // eval or global scopes only
+
+  // 1) Propagate scope information.
+  // If we are in an eval scope, we may have other outer scopes about
+  // which we don't know anything at this point. Thus we must be conservative
+  // and assume they may invoke eval themselves. Eventually we could capture
+  // this information in the ScopeInfo and then use it here (by traversing
+  // the call chain stack, at compile time).
+  bool eval_scope = is_eval_scope();
+  PropagateScopeInfo(eval_scope, eval_scope);
+
+  // 2) Resolve variables.
+  Scope* global_scope = NULL;
+  if (is_global_scope()) global_scope = this;
+  ResolveVariablesRecursively(global_scope, context);
+
+  // 3) Allocate variables.
+  AllocateVariablesRecursively();
+}
+
+
+bool Scope::AllowsLazyCompilation() const {
+  return !force_eager_compilation_ && HasTrivialOuterContext();
+}
+
+
+bool Scope::HasTrivialContext() const {
+  // A function scope has a trivial context if it always is the global
+  // context. We iteratively scan out the context chain to see if
+  // there is anything that makes this scope non-trivial; otherwise we
+  // return true.
+  for (const Scope* scope = this; scope != NULL; scope = scope->outer_scope_) {
+    if (scope->is_eval_scope()) return false;
+    if (scope->scope_inside_with_) return false;
+    if (scope->num_heap_slots_ > 0) return false;
+  }
+  return true;
+}
+
+
+bool Scope::HasTrivialOuterContext() const {
+  Scope* outer = outer_scope_;
+  if (outer == NULL) return true;
+  // Note that the outer context may be trivial in general, but the current
+  // scope may be inside a 'with' statement in which case the outer context
+  // for this scope is not trivial.
+  return !scope_inside_with_ && outer->HasTrivialContext();
+}
+
+
+int Scope::ContextChainLength(Scope* scope) {
+  int n = 0;
+  for (Scope* s = this; s != scope; s = s->outer_scope_) {
+    ASSERT(s != NULL);  // scope must be in the scope chain
+    if (s->num_heap_slots() > 0) n++;
+  }
+  return n;
+}
+
+
+#ifdef DEBUG
+static const char* Header(Scope::Type type) {
+  switch (type) {
+    case Scope::EVAL_SCOPE: return "eval";
+    case Scope::FUNCTION_SCOPE: return "function";
+    case Scope::GLOBAL_SCOPE: return "global";
+  }
+  UNREACHABLE();
+  return NULL;
+}
+
+
+static void Indent(int n, const char* str) {
+  PrintF("%*s%s", n, "", str);
+}
+
+
+static void PrintName(Handle<String> name) {
+  SmartPointer<char> s = name->ToCString(DISALLOW_NULLS);
+  PrintF("%s", *s);
+}
+
+
+static void PrintVar(PrettyPrinter* printer, int indent, Variable* var) {
+  if (var->var_uses()->is_used() || var->rewrite() != NULL) {
+    Indent(indent, Variable::Mode2String(var->mode()));
+    PrintF(" ");
+    PrintName(var->name());
+    PrintF(";  // ");
+    if (var->rewrite() != NULL) PrintF("%s, ", printer->Print(var->rewrite()));
+    if (var->is_accessed_from_inner_scope()) PrintF("inner scope access, ");
+    PrintF("var ");
+    var->var_uses()->Print();
+    PrintF(", obj ");
+    var->obj_uses()->Print();
+    PrintF("\n");
+  }
+}
+
+
+void Scope::Print(int n) {
+  int n0 = (n > 0 ? n : 0);
+  int n1 = n0 + 2;  // indentation
+
+  // Print header.
+  Indent(n0, Header(type_));
+  if (scope_name_->length() > 0) {
+    PrintF(" ");
+    PrintName(scope_name_);
+  }
+
+  // Print parameters, if any.
+  if (is_function_scope()) {
+    PrintF(" (");
+    for (int i = 0; i < params_.length(); i++) {
+      if (i > 0) PrintF(", ");
+      PrintName(params_[i]->name());
+    }
+    PrintF(")");
+  }
+
+  PrintF(" {\n");
+
+  // Function name, if any (named function literals, only).
+  if (function_ != NULL) {
+    Indent(n1, "// (local) function name: ");
+    PrintName(function_->name());
+    PrintF("\n");
+  }
+
+  // Scope info.
+  if (HasTrivialOuterContext()) {
+    Indent(n1, "// scope has trivial outer context\n");
+  }
+  if (scope_inside_with_) Indent(n1, "// scope inside 'with'\n");
+  if (scope_contains_with_) Indent(n1, "// scope contains 'with'\n");
+  if (scope_calls_eval_) Indent(n1, "// scope calls 'eval'\n");
+  if (outer_scope_calls_eval_) Indent(n1, "// outer scope calls 'eval'\n");
+  if (inner_scope_calls_eval_) Indent(n1, "// inner scope calls 'eval'\n");
+  if (outer_scope_is_eval_scope_) {
+    Indent(n1, "// outer scope is 'eval' scope\n");
+  }
+  if (num_stack_slots_ > 0) { Indent(n1, "// ");
+  PrintF("%d stack slots\n", num_stack_slots_); }
+  if (num_heap_slots_ > 0) { Indent(n1, "// ");
+  PrintF("%d heap slots\n", num_heap_slots_); }
+
+  // Print locals.
+  PrettyPrinter printer;
+  Indent(n1, "// function var\n");
+  if (function_ != NULL) {
+    PrintVar(&printer, n1, function_);
+  }
+
+  Indent(n1, "// temporary vars\n");
+  for (int i = 0; i < temps_.length(); i++) {
+    PrintVar(&printer, n1, temps_[i]);
+  }
+
+  Indent(n1, "// local vars\n");
+  for (LocalsMap::Entry* p = locals_.Start(); p != NULL; p = locals_.Next(p)) {
+    Variable* var = reinterpret_cast<Variable*>(p->value);
+    PrintVar(&printer, n1, var);
+  }
+
+  Indent(n1, "// nonlocal vars\n");
+  for (int i = 0; i < nonlocals_.length(); i++)
+    PrintVar(&printer, n1, nonlocals_[i]);
+
+  // Print inner scopes (disable by providing negative n).
+  if (n >= 0) {
+    for (int i = 0; i < inner_scopes_.length(); i++) {
+      PrintF("\n");
+      inner_scopes_[i]->Print(n1);
+    }
+  }
+
+  Indent(n0, "}\n");
+}
+#endif  // DEBUG
+
+
+Variable* Scope::NonLocal(Handle<String> name, Variable::Mode mode) {
+  // Space optimization: reuse existing non-local with the same name
+  // and mode.
+  for (int i = 0; i < nonlocals_.length(); i++) {
+    Variable* var = nonlocals_[i];
+    if (var->name().is_identical_to(name) && var->mode() == mode) {
+      return var;
+    }
+  }
+
+  // Otherwise create a new non-local and add it to the list.
+  Variable* var = new Variable(NULL, name, mode, true, false);
+  nonlocals_.Add(var);
+
+  // Allocate it by giving it a dynamic lookup.
+  var->rewrite_ = new Slot(var, Slot::LOOKUP, -1);
+
+  return var;
+}
+
+
+// Lookup a variable starting with this scope. The result is either
+// the statically resolved (local!) variable belonging to an outer scope,
+// or NULL. It may be NULL because a) we couldn't find a variable, or b)
+// because the variable is just a guess (and may be shadowed by another
+// variable that is introduced dynamically via an 'eval' call or a 'with'
+// statement).
+Variable* Scope::LookupRecursive(Handle<String> name,
+                                 bool inner_lookup,
+                                 Variable** invalidated_local) {
+  // If we find a variable, but the current scope calls 'eval', the found
+  // variable may not be the correct one (the 'eval' may introduce a
+  // property with the same name). In that case, remember that the variable
+  // found is just a guess.
+  bool guess = scope_calls_eval_;
+
+  // Try to find the variable in this scope.
+  Variable* var = LookupLocal(name);
+
+  if (var != NULL) {
+    // We found a variable. If this is not an inner lookup, we are done.
+    // (Even if there is an 'eval' in this scope which introduces the
+    // same variable again, the resulting variable remains the same.
+    // Note that enclosing 'with' statements are handled at the call site.)
+    if (!inner_lookup)
+      return var;
+
+  } else {
+    // We did not find a variable locally. Check against the function variable,
+    // if any. We can do this for all scopes, since the function variable is
+    // only present - if at all - for function scopes.
+    //
+    // This lookup corresponds to a lookup in the "intermediate" scope sitting
+    // between this scope and the outer scope. (ECMA-262, 3rd., requires that
+    // the name of named function literal is kept in an intermediate scope
+    // in between this scope and the next outer scope.)
+    if (function_ != NULL && function_->name().is_identical_to(name)) {
+      var = function_;
+
+    } else if (outer_scope_ != NULL) {
+      var = outer_scope_->LookupRecursive(name, true, invalidated_local);
+      // We may have found a variable in an outer scope. However, if
+      // the current scope is inside a 'with', the actual variable may
+      // be a property introduced via the 'with' statement. Then, the
+      // variable we may have found is just a guess.
+      if (scope_inside_with_)
+        guess = true;
+    }
+
+    // If we did not find a variable, we are done.
+    if (var == NULL)
+      return NULL;
+  }
+
+  ASSERT(var != NULL);
+
+  // If this is a lookup from an inner scope, mark the variable.
+  if (inner_lookup)
+    var->is_accessed_from_inner_scope_ = true;
+
+  // If the variable we have found is just a guess, invalidate the result.
+  if (guess) {
+    *invalidated_local = var;
+    var = NULL;
+  }
+
+  return var;
+}
+
+
+void Scope::ResolveVariable(Scope* global_scope,
+                            Handle<Context> context,
+                            VariableProxy* proxy) {
+  ASSERT(global_scope == NULL || global_scope->is_global_scope());
+
+  // If the proxy is already resolved there's nothing to do
+  // (functions and consts may be resolved by the parser).
+  if (proxy->var() != NULL) return;
+
+  // Otherwise, try to resolve the variable.
+  Variable* invalidated_local = NULL;
+  Variable* var = LookupRecursive(proxy->name(), false, &invalidated_local);
+
+  if (proxy->inside_with()) {
+    // If we are inside a local 'with' statement, all bets are off
+    // and we cannot resolve the proxy to a local variable even if
+    // we found an outer matching variable.
+    // Note that we must do a lookup anyway, because if we find one,
+    // we must mark that variable as potentially accessed from this
+    // inner scope (the property may not be in the 'with' object).
+    var = NonLocal(proxy->name(), Variable::DYNAMIC);
+
+  } else {
+    // We are not inside a local 'with' statement.
+
+    if (var == NULL) {
+      // We did not find the variable. We have a global variable
+      // if we are in the global scope (we know already that we
+      // are outside a 'with' statement) or if there is no way
+      // that the variable might be introduced dynamically (through
+      // a local or outer eval() call, or an outer 'with' statement),
+      // or we don't know about the outer scope (because we are
+      // in an eval scope).
+      if (is_global_scope() ||
+          !(scope_inside_with_ || outer_scope_is_eval_scope_ ||
+            scope_calls_eval_ || outer_scope_calls_eval_)) {
+        // We must have a global variable.
+        ASSERT(global_scope != NULL);
+        var = new Variable(global_scope, proxy->name(),
+                           Variable::DYNAMIC, true, false);
+        // Ideally we simply rewrite these variables into property
+        // accesses. Unfortunately, we cannot do this here at the
+        // moment because then we can't differentiate between
+        // global variable ('x') and global property ('this.x') access.
+        // If 'x' doesn't exist, the former leads to an error, while the
+        // latter returns undefined. Sigh...
+        // var->rewrite_ = new Property(new Literal(env_->global()),
+        //                              new Literal(proxy->name()));
+
+      } else if (scope_inside_with_) {
+        // If we are inside a with statement we give up and look up
+        // the variable at runtime.
+        var = NonLocal(proxy->name(), Variable::DYNAMIC);
+
+      } else if (invalidated_local != NULL) {
+        // No with statements are involved and we found a local
+        // variable that might be shadowed by eval introduced
+        // variables.
+        var = NonLocal(proxy->name(), Variable::DYNAMIC_LOCAL);
+        var->set_local_if_not_shadowed(invalidated_local);
+
+      } else if (outer_scope_is_eval_scope_) {
+        // No with statements and we did not find a local and the code
+        // is executed with a call to eval.  The context contains
+        // scope information that we can use to determine if the
+        // variable is global if it is not shadowed by eval-introduced
+        // variables.
+        if (context->GlobalIfNotShadowedByEval(proxy->name())) {
+          var = NonLocal(proxy->name(), Variable::DYNAMIC_GLOBAL);
+
+        } else {
+          var = NonLocal(proxy->name(), Variable::DYNAMIC);
+        }
+
+      } else {
+        // No with statements and we did not find a local and the code
+        // is not executed with a call to eval.  We know that this
+        // variable is global unless it is shadowed by eval-introduced
+        // variables.
+        var = NonLocal(proxy->name(), Variable::DYNAMIC_GLOBAL);
+      }
+    }
+  }
+
+  proxy->BindTo(var);
+}
+
+
+void Scope::ResolveVariablesRecursively(Scope* global_scope,
+                                        Handle<Context> context) {
+  ASSERT(global_scope == NULL || global_scope->is_global_scope());
+
+  // Resolve unresolved variables for this scope.
+  for (int i = 0; i < unresolved_.length(); i++) {
+    ResolveVariable(global_scope, context, unresolved_[i]);
+  }
+
+  // Resolve unresolved variables for inner scopes.
+  for (int i = 0; i < inner_scopes_.length(); i++) {
+    inner_scopes_[i]->ResolveVariablesRecursively(global_scope, context);
+  }
+}
+
+
+bool Scope::PropagateScopeInfo(bool outer_scope_calls_eval,
+                               bool outer_scope_is_eval_scope) {
+  if (outer_scope_calls_eval) {
+    outer_scope_calls_eval_ = true;
+  }
+
+  if (outer_scope_is_eval_scope) {
+    outer_scope_is_eval_scope_ = true;
+  }
+
+  bool calls_eval = scope_calls_eval_ || outer_scope_calls_eval_;
+  bool is_eval = is_eval_scope() || outer_scope_is_eval_scope_;
+  for (int i = 0; i < inner_scopes_.length(); i++) {
+    Scope* inner_scope = inner_scopes_[i];
+    if (inner_scope->PropagateScopeInfo(calls_eval, is_eval)) {
+      inner_scope_calls_eval_ = true;
+    }
+    if (inner_scope->force_eager_compilation_) {
+      force_eager_compilation_ = true;
+    }
+  }
+
+  return scope_calls_eval_ || inner_scope_calls_eval_;
+}
+
+
+bool Scope::MustAllocate(Variable* var) {
+  // Give var a read/write use if there is a chance it might be
+  // accessed via an eval() call, or if it is a global variable.
+  // This is only possible if the variable has a visible name.
+  if ((var->is_this() || var->name()->length() > 0) &&
+      (var->is_accessed_from_inner_scope_ ||
+       scope_calls_eval_ || inner_scope_calls_eval_ ||
+       scope_contains_with_ || var->is_global())) {
+    var->var_uses()->RecordAccess(1);
+  }
+  return var->var_uses()->is_used();
+}
+
+
+bool Scope::MustAllocateInContext(Variable* var) {
+  // If var is accessed from an inner scope, or if there is a
+  // possibility that it might be accessed from the current or
+  // an inner scope (through an eval() call), it must be allocated
+  // in the context.
+  // Exceptions: Global variables and temporary variables must
+  // never be allocated in the (FixedArray part of the) context.
+  return
+    var->mode() != Variable::TEMPORARY &&
+    (var->is_accessed_from_inner_scope_ ||
+     scope_calls_eval_ || inner_scope_calls_eval_ ||
+     scope_contains_with_ || var->is_global());
+}
+
+
+bool Scope::HasArgumentsParameter() {
+  for (int i = 0; i < params_.length(); i++) {
+    if (params_[i]->name().is_identical_to(Factory::arguments_symbol()))
+      return true;
+  }
+  return false;
+}
+
+
+void Scope::AllocateStackSlot(Variable* var) {
+  var->rewrite_ = new Slot(var, Slot::LOCAL, num_stack_slots_++);
+}
+
+
+void Scope::AllocateHeapSlot(Variable* var) {
+  var->rewrite_ = new Slot(var, Slot::CONTEXT, num_heap_slots_++);
+}
+
+
+void Scope::AllocateParameterLocals() {
+  ASSERT(is_function_scope());
+  Variable* arguments = LookupLocal(Factory::arguments_symbol());
+  ASSERT(arguments != NULL);  // functions have 'arguments' declared implicitly
+  if (MustAllocate(arguments) && !HasArgumentsParameter()) {
+    // 'arguments' is used. Unless there is also a parameter called
+    // 'arguments', we must be conservative and access all parameters via
+    // the arguments object: The i'th parameter is rewritten into
+    // '.arguments[i]' (*). If we have a parameter named 'arguments', a
+    // (new) value is always assigned to it via the function
+    // invocation. Then 'arguments' denotes that specific parameter value
+    // and cannot be used to access the parameters, which is why we don't
+    // need to rewrite in that case.
+    //
+    // (*) Instead of having a parameter called 'arguments', we may have an
+    // assignment to 'arguments' in the function body, at some arbitrary
+    // point in time (possibly through an 'eval()' call!). After that
+    // assignment any re-write of parameters would be invalid (was bug
+    // 881452). Thus, we introduce a shadow '.arguments'
+    // variable which also points to the arguments object. For rewrites we
+    // use '.arguments' which remains valid even if we assign to
+    // 'arguments'. To summarize: If we need to rewrite, we allocate an
+    // 'arguments' object dynamically upon function invocation. The compiler
+    // introduces 2 local variables 'arguments' and '.arguments', both of
+    // which originally point to the arguments object that was
+    // allocated. All parameters are rewritten into property accesses via
+    // the '.arguments' variable. Thus, any changes to properties of
+    // 'arguments' are reflected in the variables and vice versa. If the
+    // 'arguments' variable is changed, '.arguments' still points to the
+    // correct arguments object and the rewrites still work.
+
+    // We are using 'arguments'. Tell the code generator that is needs to
+    // allocate the arguments object by setting 'arguments_'.
+    arguments_ = new VariableProxy(Factory::arguments_symbol(), false, false);
+    arguments_->BindTo(arguments);
+
+    // We also need the '.arguments' shadow variable. Declare it and create
+    // and bind the corresponding proxy. It's ok to declare it only now
+    // because it's a local variable that is allocated after the parameters
+    // have been allocated.
+    //
+    // Note: This is "almost" at temporary variable but we cannot use
+    // NewTemporary() because the mode needs to be INTERNAL since this
+    // variable may be allocated in the heap-allocated context (temporaries
+    // are never allocated in the context).
+    Variable* arguments_shadow =
+        new Variable(this, Factory::arguments_shadow_symbol(),
+                     Variable::INTERNAL, true, false);
+    arguments_shadow_ =
+        new VariableProxy(Factory::arguments_shadow_symbol(), false, false);
+    arguments_shadow_->BindTo(arguments_shadow);
+    temps_.Add(arguments_shadow);
+
+    // Allocate the parameters by rewriting them into '.arguments[i]' accesses.
+    for (int i = 0; i < params_.length(); i++) {
+      Variable* var = params_[i];
+      ASSERT(var->scope() == this);
+      if (MustAllocate(var)) {
+        if (MustAllocateInContext(var)) {
+          // It is ok to set this only now, because arguments is a local
+          // variable that is allocated after the parameters have been
+          // allocated.
+          arguments_shadow->is_accessed_from_inner_scope_ = true;
+        }
+        var->rewrite_ =
+          new Property(arguments_shadow_,
+                       new Literal(Handle<Object>(Smi::FromInt(i))),
+                       RelocInfo::kNoPosition,
+                       Property::SYNTHETIC);
+        arguments_shadow->var_uses()->RecordUses(var->var_uses());
+      }
+    }
+
+  } else {
+    // The arguments object is not used, so we can access parameters directly.
+    // The same parameter may occur multiple times in the parameters_ list.
+    // If it does, and if it is not copied into the context object, it must
+    // receive the highest parameter index for that parameter; thus iteration
+    // order is relevant!
+    for (int i = 0; i < params_.length(); i++) {
+      Variable* var = params_[i];
+      ASSERT(var->scope() == this);
+      if (MustAllocate(var)) {
+        if (MustAllocateInContext(var)) {
+          ASSERT(var->rewrite_ == NULL ||
+                 (var->slot() != NULL && var->slot()->type() == Slot::CONTEXT));
+          if (var->rewrite_ == NULL) {
+            // Only set the heap allocation if the parameter has not
+            // been allocated yet.
+            AllocateHeapSlot(var);
+          }
+        } else {
+          ASSERT(var->rewrite_ == NULL ||
+                 (var->slot() != NULL &&
+                  var->slot()->type() == Slot::PARAMETER));
+          // Set the parameter index always, even if the parameter
+          // was seen before! (We need to access the actual parameter
+          // supplied for the last occurrence of a multiply declared
+          // parameter.)
+          var->rewrite_ = new Slot(var, Slot::PARAMETER, i);
+        }
+      }
+    }
+  }
+}
+
+
+void Scope::AllocateNonParameterLocal(Variable* var) {
+  ASSERT(var->scope() == this);
+  ASSERT(var->rewrite_ == NULL ||
+         (!var->IsVariable(Factory::result_symbol())) ||
+         (var->slot() == NULL || var->slot()->type() != Slot::LOCAL));
+  if (MustAllocate(var) && var->rewrite_ == NULL) {
+    if (MustAllocateInContext(var)) {
+      AllocateHeapSlot(var);
+    } else {
+      AllocateStackSlot(var);
+    }
+  }
+}
+
+
+void Scope::AllocateNonParameterLocals() {
+  // Each variable occurs exactly once in the locals_ list; all
+  // variables that have no rewrite yet are non-parameter locals.
+
+  // Sort them according to use such that the locals with more uses
+  // get allocated first.
+  if (FLAG_usage_computation) {
+    // This is currently not implemented.
+  }
+
+  for (int i = 0; i < temps_.length(); i++) {
+    AllocateNonParameterLocal(temps_[i]);
+  }
+
+  for (LocalsMap::Entry* p = locals_.Start(); p != NULL; p = locals_.Next(p)) {
+    Variable* var = reinterpret_cast<Variable*>(p->value);
+    AllocateNonParameterLocal(var);
+  }
+
+  // Note: For now, function_ must be allocated at the very end.  If
+  // it gets allocated in the context, it must be the last slot in the
+  // context, because of the current ScopeInfo implementation (see
+  // ScopeInfo::ScopeInfo(FunctionScope* scope) constructor).
+  if (function_ != NULL) {
+    AllocateNonParameterLocal(function_);
+  }
+}
+
+
+void Scope::AllocateVariablesRecursively() {
+  // The number of slots required for variables.
+  num_stack_slots_ = 0;
+  num_heap_slots_ = Context::MIN_CONTEXT_SLOTS;
+
+  // Allocate variables for inner scopes.
+  for (int i = 0; i < inner_scopes_.length(); i++) {
+    inner_scopes_[i]->AllocateVariablesRecursively();
+  }
+
+  // Allocate variables for this scope.
+  // Parameters must be allocated first, if any.
+  if (is_function_scope()) AllocateParameterLocals();
+  AllocateNonParameterLocals();
+
+  // Allocate context if necessary.
+  bool must_have_local_context = false;
+  if (scope_calls_eval_ || scope_contains_with_) {
+    // The context for the eval() call or 'with' statement in this scope.
+    // Unless we are in the global or an eval scope, we need a local
+    // context even if we didn't statically allocate any locals in it,
+    // and the compiler will access the context variable. If we are
+    // not in an inner scope, the scope is provided from the outside.
+    must_have_local_context = is_function_scope();
+  }
+
+  // If we didn't allocate any locals in the local context, then we only
+  // need the minimal number of slots if we must have a local context.
+  if (num_heap_slots_ == Context::MIN_CONTEXT_SLOTS &&
+      !must_have_local_context) {
+    num_heap_slots_ = 0;
+  }
+
+  // Allocation done.
+  ASSERT(num_heap_slots_ == 0 || num_heap_slots_ >= Context::MIN_CONTEXT_SLOTS);
+}
+
+} }  // namespace v8::internal