[interpreter] Make sure allocated registers are always materialized in the register optimizer.

src/interpreter/bytecode-register-optimizer.cc

 // Copyright 2016 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/interpreter/bytecode-register-optimizer.h"
 
 namespace v8 {
 namespace internal {
 namespace interpreter {
 
@@ skipping 398 matching lines @@
     size_t old_size = register_info_table_.size();
     register_info_table_.resize(new_size);
     for (size_t i = old_size; i < new_size; ++i) {
       register_info_table_[i] =
           new (zone()) RegisterInfo(RegisterFromRegisterInfoTableIndex(i),
                                     NextEquivalenceId(), true, false);
     }
   }
 }
 
+void BytecodeRegisterOptimizer::SetRegisterAllocated(Register reg) {

[rmcilroy, 2017/06/07 13:01:58]

nit - could you pull out the GetOrCreateRegisterInfo to the caller so that
RegisterListAllocateEvent can continue to use GetRegisterInfo. Also, maybe just
AllocateRegister as the name?

[Jarin, 2017/06/07 15:14:07]

Done.

+  RegisterInfo* info = GetOrCreateRegisterInfo(reg);
+  info->set_allocated(true);
+  if (!info->materialized()) {
+    info->MoveToNewEquivalenceSet(NextEquivalenceId(), true);
+  }
+}
+
 void BytecodeRegisterOptimizer::RegisterAllocateEvent(Register reg) {
-  GetOrCreateRegisterInfo(reg)->set_allocated(true);
+  SetRegisterAllocated(reg);
 }
 
 void BytecodeRegisterOptimizer::RegisterListAllocateEvent(
     RegisterList reg_list) {
   if (reg_list.register_count() != 0) {
     int first_index = reg_list.first_register().index();
     GrowRegisterMap(Register(first_index + reg_list.register_count() - 1));
     for (int i = 0; i < reg_list.register_count(); i++) {
-      GetRegisterInfo(Register(first_index + i))->set_allocated(true);
+      SetRegisterAllocated(Register(first_index + i));
     }
   }
 }
 
 void BytecodeRegisterOptimizer::RegisterListFreeEvent(RegisterList reg_list) {
   int first_index = reg_list.first_register().index();
   for (int i = 0; i < reg_list.register_count(); i++) {
     GetRegisterInfo(Register(first_index + i))->set_allocated(false);
   }
 }
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8