[turbofan]: Support using push instructions for setting up tail call parameters

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 "src/compiler/gap-resolver.h"
 #include "src/compiler/instruction.h"
 #include "src/deoptimizer.h"
@@ skipping 84 matching lines @@
 
   // Assemble instructions for the specified block.
   CodeGenResult AssembleBlock(const InstructionBlock* block);
 
   // Assemble code for the specified instruction.
   CodeGenResult AssembleInstruction(Instruction* instr,
                                     const InstructionBlock* block);
   void AssembleSourcePosition(Instruction* instr);
   void AssembleGaps(Instruction* instr);
 
+  // Returns true if a instruction needs to adjust the stack pointer before
+  // execution. The stack slot index to the empty slot above the adjusted stack
+  // pointer is returned in |slot|.
+  bool GetSlotAboveSPAfterGap(Instruction* instr, int* slot);
+
   // ===========================================================================
   // ============= Architecture-specific code generation methods. ==============
   // ===========================================================================
 
   CodeGenResult AssembleArchInstruction(Instruction* instr);
   void AssembleArchJump(RpoNumber target);
   void AssembleArchBranch(Instruction* instr, BranchInfo* branch);
   void AssembleArchBoolean(Instruction* instr, FlagsCondition condition);
   void AssembleArchLookupSwitch(Instruction* instr);
   void AssembleArchTableSwitch(Instruction* instr);
 
   CodeGenResult AssembleDeoptimizerCall(int deoptimization_id,
                                         Deoptimizer::BailoutType bailout_type);
 
   // Generates an architecture-specific, descriptor-specific prologue
   // to set up a stack frame.
   void AssembleConstructFrame();
 
   // Generates an architecture-specific, descriptor-specific return sequence
   // to tear down a stack frame.
   void AssembleReturn();
 
-  // Generates code to deconstruct a the caller's frame, including arguments.
-  void AssembleDeconstructActivationRecord(int stack_param_delta);
-
   void AssembleDeconstructFrame();
 
   // Generates code to manipulate the stack in preparation for a tail call.
-  void AssemblePrepareTailCall(int stack_param_delta);
+  void AssemblePrepareTailCall();
 
   // Generates code to pop current frame if it is an arguments adaptor frame.
   void AssemblePopArgumentsAdaptorFrame(Register args_reg, Register scratch1,
                                         Register scratch2, Register scratch3);
 
+  void AssemblePreGaps(Instruction* instr);

[Mircea Trofin, 2016/06/30 15:32:34]

Code comment on what these do.

[danno, 2016/07/01 07:31:57]

Done.

+  void AssemblePostGaps(Instruction* instr);
+
   // ===========================================================================
   // ============== Architecture-specific gap resolver methods. ================
   // ===========================================================================
 
   // Interface used by the gap resolver to emit moves and swaps.
   void AssembleMove(InstructionOperand* source,
                     InstructionOperand* destination) final;
   void AssembleSwap(InstructionOperand* source,
                     InstructionOperand* destination) final;
 
@@ skipping 32 matching lines @@
                                              OutputFrameStateCombine combine,
                                              Translation* translation);
   void AddTranslationForOperand(Translation* translation, Instruction* instr,
                                 InstructionOperand* op, MachineType type);
   void EnsureSpaceForLazyDeopt();
   void MarkLazyDeoptSite();
 
   DeoptimizationExit* AddDeoptimizationExit(Instruction* instr,
                                             size_t frame_state_offset);
 
-  // Converts the delta in the number of stack parameter passed from a tail
-  // caller to the callee into the distance (in pointers) the SP must be
-  // adjusted, taking frame elision and other relevant factors into
-  // consideration.
-  int TailCallFrameStackSlotDelta(int stack_param_delta);
-
   // ===========================================================================
 
   struct DeoptimizationState : ZoneObject {
    public:
     BailoutId bailout_id() const { return bailout_id_; }
     int translation_id() const { return translation_id_; }
     int pc_offset() const { return pc_offset_; }
 
     DeoptimizationState(BailoutId bailout_id, int translation_id, int pc_offset)
         : bailout_id_(bailout_id),
@@ skipping 36 matching lines @@
   OutOfLineCode* ools_;
   int osr_pc_offset_;
   SourcePositionTableBuilder source_position_table_builder_;
 };
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_COMPILER_CODE_GENERATOR_H