[turbofan] remove spill slot reuse flag

src/compiler/pipeline.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/compiler/pipeline.h"
 
 #include <fstream>  // NOLINT(readability/streams)
 #include <sstream>
 
 #include "src/base/platform/elapsed-timer.h"
@@ skipping 566 matching lines @@
 
 struct AllocateDoubleRegistersPhase {
   static const char* phase_name() { return "allocate double registers"; }
 
   void Run(PipelineData* data, Zone* temp_zone) {
     data->register_allocator()->AllocateDoubleRegisters();
   }
 };
 
 
-struct ReuseSpillSlotsPhase {
-  static const char* phase_name() { return "reuse spill slots"; }
+struct AssignSpillSlotsPhase {
+  static const char* phase_name() { return "assign spill slots"; }
 
   void Run(PipelineData* data, Zone* temp_zone) {
-    data->register_allocator()->ReuseSpillSlots();
+    data->register_allocator()->AssignSpillSlots();
   }
 };
 
 
 struct CommitAssignmentPhase {
   static const char* phase_name() { return "commit assignment"; }
 
   void Run(PipelineData* data, Zone* temp_zone) {
     data->register_allocator()->CommitAssignment();
   }
@@ skipping 427 matching lines @@
     OFStream os(stdout);
     PrintableInstructionSequence printable = {config, data->sequence()};
     os << "----- Instruction sequence before register allocation -----\n"
        << printable;
   }
   if (verifier != nullptr) {
     CHECK(!data->register_allocator()->ExistsUseWithoutDefinition());
   }
   Run<AllocateGeneralRegistersPhase>();
   Run<AllocateDoubleRegistersPhase>();
-  if (FLAG_turbo_reuse_spill_slots) {
-    Run<ReuseSpillSlotsPhase>();
-  }
+  Run<AssignSpillSlotsPhase>();
+
   Run<CommitAssignmentPhase>();
   Run<PopulatePointerMapsPhase>();
   Run<ConnectRangesPhase>();
   Run<ResolveControlFlowPhase>();
   if (FLAG_turbo_move_optimization) {
     Run<OptimizeMovesPhase>();
   }
 
   if (FLAG_trace_turbo_graph) {
     OFStream os(stdout);
@@ skipping 19 matching lines @@
 }
 
 
 void Pipeline::TearDown() {
   InstructionOperand::TearDownCaches();
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8