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

src/compiler/code-generator.h

Index: src/compiler/code-generator.h
diff --git a/src/compiler/code-generator.h b/src/compiler/code-generator.h
index 1083e66e023b0d350d50ba2798a8358a15cb167c..d9fa7e5ebbbc4305231f7b17668d14dacdab10d1 100644
--- a/src/compiler/code-generator.h
+++ b/src/compiler/code-generator.h
@@ -102,6 +102,11 @@ class CodeGenerator final : public GapResolver::Assembler {
   void AssembleSourcePosition(Instruction* instr);
   void AssembleGaps(Instruction* instr);
 
+  // Returns true if a instruction is a tail call that 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 GetSlotAboveSPBeforeTailCall(Instruction* instr, int* slot);
+
   // ===========================================================================
   // ============= Architecture-specific code generation methods. ==============
   // ===========================================================================
@@ -124,18 +129,49 @@ class CodeGenerator final : public GapResolver::Assembler {
   // 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);
 
+  enum PushTypeFlag {
+    kImmediatePush = 0x1,
+    kScalarPush = 0x2,
+    kFloat32Push = 0x4,
+    kFloat64Push = 0x8,
+    kFloatPush = kFloat32Push | kFloat64Push
+  };
+
+  typedef base::Flags<PushTypeFlag> PushTypeFlags;
+
+  static bool IsValidPush(InstructionOperand source, PushTypeFlags push_type);
+
+  // Generate a list moves from an instruction that are candidates to be turned
+  // into push instructions on platforms that support them. In general, the list
+  // of push candidates are moves to a set of contiguous destination
+  // InstructionOperand locations on the stack that don't clobber values that
+  // are needed for resolve the gap or use values generated by the gap,
+  // i.e. moves that can be hoisted together before the actual gap and assembled
+  // together.
+  static void GetPushCompatibleMoves(Instruction* instr,
+                                     PushTypeFlags push_type,
+                                     ZoneVector<MoveOperands*>* pushes);
+
+  // Called before a tail call |instr|'s gap moves are assembled and allows
+  // gap-specific pre-processing, e.g. adjustment of the sp for tail calls that
+  // need it before gap moves or conversion of certain gap moves into pushes.
+  void AssembleTailCallBeforeGap(Instruction* instr,
+                                 int first_unused_stack_slot);
+  // Called after a tail call |instr|'s gap moves are assembled and allows
+  // gap-specific post-processing, e.g. adjustment of the sp for tail calls that
+  // need it after gap moves.
+  void AssembleTailCallAfterGap(Instruction* instr,
+                                int first_unused_stack_slot);
+
   // ===========================================================================
   // ============== Architecture-specific gap resolver methods. ================
   // ===========================================================================
@@ -188,12 +224,6 @@ class CodeGenerator final : public GapResolver::Assembler {
   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 {