[Interpreter] Replace BytecodeRegisterAllocator with a simple bump pointer.

src/interpreter/mkpeephole.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 <array>
 #include <fstream>
 #include <map>
 #include <string>
 #include <vector>
 
@@ skipping 128 matching lines @@
   }
 
   // Ldar and Star make the accumulator and register hold equivalent
   // values. Only the first bytecode is needed if there's a sequence
   // of back-to-back Ldar and Star bytecodes with the same operand.
   if (Bytecodes::IsLdarOrStar(last) && Bytecodes::IsLdarOrStar(current)) {
     return {PeepholeAction::kElideCurrentIfOperand0MatchesAction,
             Bytecode::kIllegal};
   }
 
+  // TODO(rmcilroy): Add elide for consecutive mov to and from the same
+  // register.
+
   // Remove ToBoolean coercion from conditional jumps where possible.
   if (Bytecodes::WritesBooleanToAccumulator(last)) {
     if (Bytecodes::IsJumpIfToBoolean(current)) {
       return {PeepholeAction::kChangeJumpBytecodeAction,
               Bytecodes::GetJumpWithoutToBoolean(current)};
     } else if (current == Bytecode::kToBooleanLogicalNot) {
       return {PeepholeAction::kChangeBytecodeAction, Bytecode::kLogicalNot};
     }
   }
 
@@ skipping 215 matching lines @@
 
   std::ofstream ofs(argv[1], std::ofstream::trunc);
   v8::internal::interpreter::PeepholeActionTableWriter writer;
   writer.BuildTable();
   writer.Write(ofs);
   ofs.flush();
   ofs.close();
 
   return 0;
 }