Merge changes up to V8 version 2.1.3 into the partial snapshots

src/variables.cc

 // 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
@@ skipping 17 matching lines @@
 #include "v8.h"
 
 #include "ast.h"
 #include "scopes.h"
 #include "variables.h"
 
 namespace v8 {
 namespace internal {
 
 // ----------------------------------------------------------------------------
-// Implementation UseCount.
-
-UseCount::UseCount()
-  : nreads_(0),
-    nwrites_(0) {
-}
-
-
-void UseCount::RecordRead(int weight) {
-  ASSERT(weight > 0);
-  nreads_ += weight;
-  // We must have a positive nreads_ here. Handle
-  // any kind of overflow by setting nreads_ to
-  // some large-ish value.
-  if (nreads_ <= 0) nreads_ = 1000000;
-  ASSERT(is_read() & is_used());
-}
-
-
-void UseCount::RecordWrite(int weight) {
-  ASSERT(weight > 0);
-  nwrites_ += weight;
-  // We must have a positive nwrites_ here. Handle
-  // any kind of overflow by setting nwrites_ to
-  // some large-ish value.
-  if (nwrites_ <= 0) nwrites_ = 1000000;
-  ASSERT(is_written() && is_used());
-}
-
-
-void UseCount::RecordAccess(int weight) {
-  RecordRead(weight);
-  RecordWrite(weight);
-}
-
-
-void UseCount::RecordUses(UseCount* uses) {
-  if (uses->nreads() > 0) RecordRead(uses->nreads());
-  if (uses->nwrites() > 0) RecordWrite(uses->nwrites());
-}
-
-
-#ifdef DEBUG
-void UseCount::Print() {
-  // PrintF("r = %d, w = %d", nreads_, nwrites_);
-  PrintF("%du = %dr + %dw", nuses(), nreads(), nwrites());
-}
-#endif
-
-
-// ----------------------------------------------------------------------------
 // Implementation StaticType.
 
 
 const char* StaticType::Type2String(StaticType* type) {
   switch (type->kind_) {
     case UNKNOWN:
       return "UNKNOWN";
     case LIKELY_SMI:
       return "LIKELY_SMI";
     default:
@@ skipping 30 matching lines @@
 Variable* Variable::AsVariable()  {
   return rewrite_ == NULL || rewrite_->AsSlot() != NULL ? this : NULL;
 }
 
 
 Slot* Variable::slot() const {
   return rewrite_ != NULL ? rewrite_->AsSlot() : NULL;
 }
 
 
+bool Variable::IsStackAllocated() const {
+  Slot* s = slot();
+  return s != NULL && s->IsStackAllocated();
+}
+
+
 Variable::Variable(Scope* scope,
                    Handle<String> name,
                    Mode mode,
                    bool is_valid_LHS,
                    Kind kind)
   : scope_(scope),
     name_(name),
     mode_(mode),
     is_valid_LHS_(is_valid_LHS),
     kind_(kind),
     local_if_not_shadowed_(NULL),
     is_accessed_from_inner_scope_(false),
+    is_used_(false),
     rewrite_(NULL) {
   // names must be canonicalized for fast equality checks
   ASSERT(name->IsSymbol());
 }
 
 
 bool Variable::is_global() const {
   // Temporaries are never global, they must always be allocated in the
   // activation frame.
   return mode_ != TEMPORARY && scope_ != NULL && scope_->is_global_scope();
 }
 
 } }  // namespace v8::internal