Fuse compare with branch at graph building time.

runtime/vm/flow_graph_compiler_x64.cc

 // Copyright (c) 2012, 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/globals.h"  // Needed here to get TARGET_ARCH_X64.
 #if defined(TARGET_ARCH_X64)
 
 #include "vm/flow_graph_compiler.h"
 
 #include "lib/error.h"
@@ skipping 624 matching lines @@
 
 void FlowGraphCompiler::EmitInstructionPrologue(Instruction* instr) {
   LocationSummary* locs = instr->locs();
   ASSERT(locs != NULL);
 
   frame_register_allocator()->AllocateRegisters(instr);
 
   // TODO(vegorov): adjust assertion when we start removing comparison from the
   // graph when it is merged with a branch.
   ASSERT(locs->is_call() ||
-         (instr->IsBranch() && instr->AsBranch()->is_fused_with_comparison()) ||
          (locs->input_count() == instr->InputCount()));
 }
 
 
 void FlowGraphCompiler::CopyParameters() {
   const Function& function = parsed_function().function();
   const bool is_native_instance_closure =
       function.is_native() && function.IsImplicitInstanceClosureFunction();
   LocalScope* scope = parsed_function().node_sequence()->scope();
   const int num_fixed_params = function.num_fixed_parameters();
@@ skipping 495 matching lines @@
     }
   }
 }
 
 
 #undef __
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_X64