AST nodes have at most one bailout/typefeedback ID now, saving lots of memory.

src/ast.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/ast.h"
 
 #include <cmath>  // For isfinite.
 #include "src/builtins.h"
 #include "src/code-stubs.h"
 #include "src/contexts.h"
@@ skipping 43 matching lines @@
   Variable* var = var_proxy->var();
   // The global identifier "undefined" is immutable. Everything
   // else could be reassigned.
   return var != NULL && var->location() == Variable::UNALLOCATED &&
          var_proxy->raw_name()->IsOneByteEqualTo("undefined");
 }
 
 
 VariableProxy::VariableProxy(Zone* zone, Variable* var, int position,
                              IdGen* id_gen)
-    : Expression(zone, position, id_gen),
+    : Expression(zone, position, 0, id_gen),
       raw_name_(var->raw_name()),
       interface_(var->interface()),
       variable_feedback_slot_(kInvalidFeedbackSlot),
       is_this_(var->is_this()),
       is_assigned_(false),
       is_resolved_(false) {
   BindTo(var);
 }
 
 
 VariableProxy::VariableProxy(Zone* zone, const AstRawString* name, bool is_this,
                              Interface* interface, int position, IdGen* id_gen)
-    : Expression(zone, position, id_gen),
+    : Expression(zone, position, 0, id_gen),
       raw_name_(name),
       interface_(interface),
       variable_feedback_slot_(kInvalidFeedbackSlot),
       is_this_(is_this),
       is_assigned_(false),
       is_resolved_(false) {}
 
 
 void VariableProxy::BindTo(Variable* var) {
   DCHECK(!FLAG_harmony_modules || interface_->IsUnified(var->interface()));
   DCHECK((is_this() && var->is_this()) || raw_name() == var->raw_name());
   // Ideally CONST-ness should match. However, this is very hard to achieve
   // because we don't know the exact semantics of conflicting (const and
   // non-const) multiple variable declarations, const vars introduced via
   // eval() etc.  Const-ness and variable declarations are a complete mess
   // in JS. Sigh...
   set_var(var);
   set_is_resolved();
   var->set_is_used();
 }
 
 
 Assignment::Assignment(Zone* zone, Token::Value op, Expression* target,
                        Expression* value, int pos, IdGen* id_gen)
-    : Expression(zone, pos, id_gen),
+    : Expression(zone, pos, num_ids(), id_gen),
       op_(op),
       target_(target),
       value_(value),
       binary_operation_(NULL),
-      assignment_id_(id_gen->GetNextId()),
       is_uninitialized_(false),
       store_mode_(STANDARD_STORE) {}
 
 
 Token::Value Assignment::binary_op() const {
   switch (op_) {
     case Token::ASSIGN_BIT_OR: return Token::BIT_OR;
     case Token::ASSIGN_BIT_XOR: return Token::BIT_XOR;
     case Token::ASSIGN_BIT_AND: return Token::BIT_AND;
     case Token::ASSIGN_SHL: return Token::SHL;
@@ skipping 864 matching lines @@
     int node_min_match = node->min_match();
     min_match_ = IncreaseBy(min_match_, node_min_match);
     int node_max_match = node->max_match();
     max_match_ = IncreaseBy(max_match_, node_max_match);
   }
 }
 
 
 CaseClause::CaseClause(Zone* zone, Expression* label,
                        ZoneList<Statement*>* statements, int pos, IdGen* id_gen)
-    : Expression(zone, pos, id_gen),
+    : Expression(zone, pos, num_ids(), id_gen),
       label_(label),
       statements_(statements),
-      compare_type_(Type::None(zone)),
-      compare_id_(id_gen->GetNextId()),
-      entry_id_(id_gen->GetNextId()) {}
+      compare_type_(Type::None(zone)) {}
 
 
 #define REGULAR_NODE(NodeType)                                   \
   void AstConstructionVisitor::Visit##NodeType(NodeType* node) { \
     increase_node_count();                                       \
   }
 #define REGULAR_NODE_WITH_FEEDBACK_SLOTS(NodeType)               \
   void AstConstructionVisitor::Visit##NodeType(NodeType* node) { \
     increase_node_count();                                       \
     add_slot_node(node);                                         \
@@ skipping 137 matching lines @@
 // static
 bool Literal::Match(void* literal1, void* literal2) {
   const AstValue* x = static_cast<Literal*>(literal1)->raw_value();
   const AstValue* y = static_cast<Literal*>(literal2)->raw_value();
   return (x->IsString() && y->IsString() && *x->AsString() == *y->AsString()) ||
          (x->IsNumber() && y->IsNumber() && x->AsNumber() == y->AsNumber());
 }
 
 
 } }  // namespace v8::internal