[turbofan] remove some of the dependency of Instruction on Schedule

src/compiler/code-generator.h

 // 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.
 
 #ifndef V8_COMPILER_CODE_GENERATOR_H_
 #define V8_COMPILER_CODE_GENERATOR_H_
 
 #include <deque>
 
 #include "src/compiler/gap-resolver.h"
@@ skipping 21 matching lines @@
   Schedule* schedule() const { return code()->schedule(); }
 
  private:
   MacroAssembler* masm() { return &masm_; }
   GapResolver* resolver() { return &resolver_; }
   SafepointTableBuilder* safepoints() { return &safepoints_; }
   Zone* zone() const { return code()->zone(); }
 
   // Checks if {block} will appear directly after {current_block_} when
   // assembling code, in which case, a fall-through can be used.
-  bool IsNextInAssemblyOrder(const BasicBlock* block) const {
-    return block->rpo_number() == (current_block_->rpo_number() + 1) &&
-           block->deferred() == current_block_->deferred();
+  bool IsNextInAssemblyOrder(BasicBlock::RpoNumber block) const {
+    return current_block_.IsNext(block);
   }
 
   // Record a safepoint with the given pointer map.
   void RecordSafepoint(PointerMap* pointers, Safepoint::Kind kind,
                        int arguments, Safepoint::DeoptMode deopt_mode);
 
   // Assemble code for the specified instruction.
   void AssembleInstruction(Instruction* instr);
   void AssembleSourcePosition(SourcePositionInstruction* instr);
   void AssembleGap(GapInstruction* gap);
@@ skipping 57 matching lines @@
           translation_id_(translation_id),
           pc_offset_(pc_offset) {}
 
    private:
     BailoutId bailout_id_;
     int translation_id_;
     int pc_offset_;
   };
 
   InstructionSequence* code_;
-  BasicBlock* current_block_;
+  BasicBlock::RpoNumber current_block_;
   SourcePosition current_source_position_;
   MacroAssembler masm_;
   GapResolver resolver_;
   SafepointTableBuilder safepoints_;
   ZoneDeque<DeoptimizationState*> deoptimization_states_;
   ZoneDeque<Handle<Object> > deoptimization_literals_;
   TranslationBuffer translations_;
   int last_lazy_deopt_pc_;
 };
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_COMPILER_CODE_GENERATOR_H