Lowered kMaxVirtualRegisters (fixes v8 2139 and chrome 123822 and 128252).

src/lithium.h

 // Copyright 2012 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 135 matching lines @@
   class LifetimeField
       : public BitField<Lifetime, kLifetimeShift, kLifetimeWidth> {
   };
 
   class VirtualRegisterField
       : public BitField<unsigned,
                         kVirtualRegisterShift,
                         kVirtualRegisterWidth> {
   };
 
-  static const int kMaxVirtualRegisters = 1 << kVirtualRegisterWidth;
+  // kMaxVirtualRegisters should not exceed 1 << kVirtualRegisterWidth but we
+  // are setting it to a lower value otherwise crankshaft is too slow.
+  STATIC_ASSERT(kVirtualRegisterWidth > 13);
+  static const int kMaxVirtualRegisters = 1 << 13;

[Vyacheslav Egorov (Google), 2012/09/21 11:42:08]

can you give some of this bits to other fields?

if you increase kMax/MinFixedIndex it will help Issue 2223. 

   static const int kMaxFixedIndex = 63;
   static const int kMinFixedIndex = -64;
 
   bool HasAnyPolicy() const {
     return policy() == ANY;
   }
   bool HasFixedPolicy() const {
     return policy() == FIXED_REGISTER ||
         policy() == FIXED_DOUBLE_REGISTER ||
         policy() == FIXED_SLOT;
@@ skipping 534 matching lines @@
   ZoneList<Handle<JSFunction> > inlined_closures_;
 };
 
 
 int ElementsKindToShiftSize(ElementsKind elements_kind);
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_LITHIUM_H_