VM: Remove dead code from flow graph optimizer.

runtime/vm/precompiler.cc

 // Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/precompiler.h"
 
 #include "vm/assembler.h"
 #include "vm/ast_printer.h"
 #include "vm/branch_optimizer.h"
 #include "vm/cha.h"
 #include "vm/code_generator.h"
 #include "vm/code_patcher.h"
 #include "vm/compiler.h"
 #include "vm/constant_propagator.h"
 #include "vm/dart_entry.h"
 #include "vm/disassembler.h"
 #include "vm/exceptions.h"
 #include "vm/flags.h"
 #include "vm/flow_graph.h"
 #include "vm/flow_graph_allocator.h"
 #include "vm/flow_graph_builder.h"
 #include "vm/flow_graph_compiler.h"
 #include "vm/flow_graph_inliner.h"
 #include "vm/flow_graph_optimizer.h"
+#include "vm/flow_graph_range_analysis.h"
 #include "vm/flow_graph_type_propagator.h"
 #include "vm/hash_table.h"
 #include "vm/il_printer.h"
 #include "vm/isolate.h"
 #include "vm/log.h"
 #include "vm/longjump.h"
 #include "vm/object.h"
 #include "vm/object_store.h"
 #include "vm/os.h"
 #include "vm/parser.h"
@@ skipping 1875 matching lines @@
                                      "RangeAnalysis");
 #endif  // !PRODUCT
           // Propagate types after store-load-forwarding. Some phis may have
           // become smi phis that can be processed by range analysis.
           FlowGraphTypePropagator::Propagate(flow_graph);
           DEBUG_ASSERT(flow_graph->VerifyUseLists());
 
           // We have to perform range analysis after LICM because it
           // optimistically moves CheckSmi through phis into loop preheaders
           // making some phis smi.
-          optimizer.InferIntRanges();
+          RangeAnalysis range_analysis(flow_graph);
+          range_analysis.Analyze();
           DEBUG_ASSERT(flow_graph->VerifyUseLists());
         }
 
         if (FLAG_constant_propagation) {
 #ifndef PRODUCT
           TimelineDurationScope tds2(thread(),
                                      compiler_timeline,
                                      "ConstantPropagator::OptimizeBranches");
 #endif  // !PRODUCT
           // Constant propagation can use information from range analysis to
@@ skipping 299 matching lines @@
       CompilationPipeline::New(thread->zone(), function);
 
   ASSERT(FLAG_precompilation);
   const bool optimized = function.IsOptimizable();  // False for natives.
   return PrecompileFunctionHelper(pipeline, function, optimized);
 }
 
 #endif  // DART_PRECOMPILER
 
 }  // namespace dart