Remove variable rewrites and the unneccesary Slot class.

src/scopeinfo.cc

Index: src/scopeinfo.cc
diff --git a/src/scopeinfo.cc b/src/scopeinfo.cc
index 6d1ffb99b8448687dbe133baf647fc1798efd170..ad31ca47c613350f3293787df8a0eebe4a3c4705 100644
--- a/src/scopeinfo.cc
+++ b/src/scopeinfo.cc
@@ -39,12 +39,8 @@ namespace internal {
 
 
 static int CompareLocal(Variable* const* v, Variable* const* w) {
-  Slot* s = (*v)->AsSlot();
-  Slot* t = (*w)->AsSlot();
-  // We may have rewritten parameters (that are in the arguments object)
-  // and which may have a NULL slot... - find a better solution...
-  int x = (s != NULL ? s->index() : 0);
-  int y = (t != NULL ? t->index() : 0);
+  int x = (*v)->index();
+  int y = (*w)->index();
   // Consider sorting them according to type as well?
   return x - y;
 }
@@ -86,27 +82,24 @@ ScopeInfo<Allocator>::ScopeInfo(Scope* scope)
   for (int i = 0; i < locals.length(); i++) {
     Variable* var = locals[i];
     if (var->is_used()) {
-      Slot* slot = var->AsSlot();
-      if (slot != NULL) {
-        switch (slot->type()) {
-          case Slot::PARAMETER:
-            // explicitly added to parameters_ above - ignore
-            break;
-
-          case Slot::LOCAL:
-            ASSERT(stack_slots_.length() == slot->index());
-            stack_slots_.Add(var->name());
-            break;
-
-          case Slot::CONTEXT:
-            heap_locals.Add(var);
-            break;
-
-          case Slot::LOOKUP:
-            // This is currently not used.
-            UNREACHABLE();
-            break;
-        }
+      switch (var->location()) {
+        case Variable::UNALLOCATED:
+        case Variable::PARAMETER:
+          break;
+
+        case Variable::LOCAL:
+          ASSERT(stack_slots_.length() == var->index());
+          stack_slots_.Add(var->name());
+          break;
+
+        case Variable::CONTEXT:
+          heap_locals.Add(var);
+          break;
+
+        case Variable::LOOKUP:
+          // We don't expect lookup variables in the locals list.
+          UNREACHABLE();
+          break;
       }
     }
   }
@@ -115,9 +108,9 @@ ScopeInfo<Allocator>::ScopeInfo(Scope* scope)
   if (scope->num_heap_slots() > 0) {
     // Add user-defined slots.
     for (int i = 0; i < heap_locals.length(); i++) {
-      ASSERT(heap_locals[i]->AsSlot()->index() - Context::MIN_CONTEXT_SLOTS ==
+      ASSERT(heap_locals[i]->index() - Context::MIN_CONTEXT_SLOTS ==
              context_slots_.length());
-      ASSERT(heap_locals[i]->AsSlot()->index() - Context::MIN_CONTEXT_SLOTS ==
+      ASSERT(heap_locals[i]->index() - Context::MIN_CONTEXT_SLOTS ==
              context_modes_.length());
       context_slots_.Add(heap_locals[i]->name());
       context_modes_.Add(heap_locals[i]->mode());
@@ -140,9 +133,9 @@ ScopeInfo<Allocator>::ScopeInfo(Scope* scope)
       // list - instead it must be handled separately in the
       // Contexts::Lookup() function. Thus record an empty symbol here so we
       // get the correct number of context slots.
-      ASSERT(proxy->var()->AsSlot()->index() - Context::MIN_CONTEXT_SLOTS ==
+      ASSERT(proxy->var()->index() - Context::MIN_CONTEXT_SLOTS ==
              context_slots_.length());
-      ASSERT(proxy->var()->AsSlot()->index() - Context::MIN_CONTEXT_SLOTS ==
+      ASSERT(proxy->var()->index() - Context::MIN_CONTEXT_SLOTS ==
              context_modes_.length());
       context_slots_.Add(FACTORY->empty_symbol());
       context_modes_.Add(Variable::INTERNAL);