[turbofan] add non fixed slot constraint to register allocator

test/unittests/compiler/instruction-sequence-unittest.cc

 // Copyright 2014 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/base/utils/random-number-generator.h"
 #include "src/compiler/pipeline.h"
 #include "test/unittests/compiler/instruction-sequence-unittest.h"
 #include "test/unittests/test-utils.h"
 #include "testing/gmock/include/gmock/gmock.h"
 
@@ skipping 355 matching lines @@
     case kNone:
       return Unallocated(op, UnallocatedOperand::NONE,
                          UnallocatedOperand::USED_AT_START);
     case kUnique:
       return Unallocated(op, UnallocatedOperand::NONE);
     case kUniqueRegister:
       return Unallocated(op, UnallocatedOperand::MUST_HAVE_REGISTER);
     case kRegister:
       return Unallocated(op, UnallocatedOperand::MUST_HAVE_REGISTER,
                          UnallocatedOperand::USED_AT_START);
+    case kSlot:
+      return Unallocated(op, UnallocatedOperand::MUST_HAVE_SLOT,
+                         UnallocatedOperand::USED_AT_START);
     case kFixedRegister:
       CHECK(0 <= op.value_ && op.value_ < num_general_registers_);
       return Unallocated(op, UnallocatedOperand::FIXED_REGISTER, op.value_);
     case kFixedSlot:
       return Unallocated(op, UnallocatedOperand::FIXED_SLOT, op.value_);
     default:
       break;
   }
   CHECK(false);
   return InstructionOperand();
@@ skipping 97 matching lines @@
 
 
 Instruction* InstructionSequenceTest::AddInstruction(Instruction* instruction) {
   sequence()->AddInstruction(instruction);
   return instruction;
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8