[turbofan] Make MachineType a pair of enums.

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/adapters.h"
@@ skipping 87 matching lines @@
         sequence_(nullptr),
         frame_(nullptr),
         register_allocation_zone_scope_(zone_pool_),
         register_allocation_zone_(register_allocation_zone_scope_.zone()),
         register_allocation_data_(nullptr) {
     PhaseScope scope(pipeline_statistics, "init pipeline data");
     graph_ = new (graph_zone_) Graph(graph_zone_);
     source_positions_.Reset(new SourcePositionTable(graph_));
     simplified_ = new (graph_zone_) SimplifiedOperatorBuilder(graph_zone_);
     machine_ = new (graph_zone_) MachineOperatorBuilder(
-        graph_zone_, kMachPtr,
+        graph_zone_, MachineType::PointerRepresentation(),
         InstructionSelector::SupportedMachineOperatorFlags());
     common_ = new (graph_zone_) CommonOperatorBuilder(graph_zone_);
     javascript_ = new (graph_zone_) JSOperatorBuilder(graph_zone_);
     jsgraph_ = new (graph_zone_)
         JSGraph(isolate_, graph_, common_, javascript_, simplified_, machine_);
   }
 
   // For machine graph testing entry point.
   PipelineData(ZonePool* zone_pool, CompilationInfo* info, Graph* graph,
                Schedule* schedule)
@@ skipping 1361 matching lines @@
     tcf << AsC1VRegisterAllocationData("CodeGen",
                                        data->register_allocation_data());
   }
 
   data->DeleteRegisterAllocationZone();
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8