Improvements for x87 stack handling

src/ia32/lithium-codegen-ia32.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 50 matching lines @@
         inlined_function_count_(0),
         scope_(info->scope()),
         status_(UNUSED),
         translations_(info->zone()),
         deferred_(8, info->zone()),
         dynamic_frame_alignment_(false),
         support_aligned_spilled_doubles_(false),
         osr_pc_offset_(-1),
         last_lazy_deopt_pc_(0),
         frame_is_built_(false),
+        x87_stack_depth_(0),
         safepoints_(info->zone()),
         resolver_(this),
         expected_safepoint_kind_(Safepoint::kSimple) {
     PopulateDeoptimizationLiteralsWithInlinedFunctions();
   }
 
   // Simple accessors.
   MacroAssembler* masm() const { return masm_; }
   CompilationInfo* info() const { return info_; }
   Isolate* isolate() const { return info_->isolate(); }
@@ skipping 14 matching lines @@
   Operand ToOperand(LOperand* op) const;
   Register ToRegister(LOperand* op) const;
   XMMRegister ToDoubleRegister(LOperand* op) const;
   bool IsX87TopOfStack(LOperand* op) const;
 
   bool IsInteger32(LConstantOperand* op) const;
   Immediate ToInteger32Immediate(LOperand* op) const {
     return Immediate(ToInteger32(LConstantOperand::cast(op)));
   }
 
+  // Support for non-sse2 (x87) floating point stack handling.
+  // These functions maintain the depth of the stack (either 0 or 1)
+  void PushX87DoubleOperand(Operand src);
+  void PushX87FloatOperand(Operand src);
+  void ReadX87Operand(Operand dst);
+  bool X87StackNonEmpty() const { return x87_stack_depth_ > 0; }
+  void PopX87();
+  void CurrentInstructionReturnsX87Result();
+  void FlushX87StackIfNecessary(LInstruction* instr);
+
   Handle<Object> ToHandle(LConstantOperand* op) const;
 
-  // A utility for instructions that return floating point values on X87.
-  void HandleX87FPReturnValue(LInstruction* instr);
-
   // The operand denoting the second word (the one with a higher address) of
   // a double stack slot.
   Operand HighOperand(LOperand* op);
 
   // Try to generate code for the entire chunk, but it may fail if the
   // chunk contains constructs we cannot handle. Returns true if the
   // code generation attempt succeeded.
   bool GenerateCode();
 
   // Finish the code by setting stack height, safepoint, and bailout
   // information on it.
   void FinishCode(Handle<Code> code);
 
   // Deferred code support.
   void DoDeferredNumberTagD(LNumberTagD* instr);
 
   enum IntegerSignedness { SIGNED_INT32, UNSIGNED_INT32 };
   void DoDeferredNumberTagI(LInstruction* instr,
                             LOperand* value,
                             IntegerSignedness signedness);
 
   void DoDeferredTaggedToI(LTaggedToI* instr);
+  void DoDeferredTaggedToINoSSE2(LTaggedToINoSSE2* instr);
   void DoDeferredMathAbsTaggedHeapNumber(LUnaryMathOperation* instr);
   void DoDeferredStackCheck(LStackCheck* instr);
   void DoDeferredRandom(LRandom* instr);
   void DoDeferredStringCharCodeAt(LStringCharCodeAt* instr);
   void DoDeferredStringCharFromCode(LStringCharFromCode* instr);
   void DoDeferredAllocateObject(LAllocateObject* instr);
   void DoDeferredAllocate(LAllocate* instr);
   void DoDeferredInstanceOfKnownGlobal(LInstanceOfKnownGlobal* instr,
                                        Label* map_check);
 
@@ skipping 166 matching lines @@
   void EmitBranch(int left_block, int right_block, Condition cc);
   void EmitNumberUntagD(
       Register input,
       Register temp,
       XMMRegister result,
       bool deoptimize_on_undefined,
       bool deoptimize_on_minus_zero,
       LEnvironment* env,
       NumberUntagDMode mode = NUMBER_CANDIDATE_IS_ANY_TAGGED);
 
+  void EmitNumberUntagDNoSSE2(
+      Register input,
+      Register temp,
+      bool deoptimize_on_undefined,
+      bool deoptimize_on_minus_zero,
+      LEnvironment* env,
+      NumberUntagDMode mode = NUMBER_CANDIDATE_IS_ANY_TAGGED);
+
   // Emits optimized code for typeof x == "y".  Modifies input register.
   // Returns the condition on which a final split to
   // true and false label should be made, to optimize fallthrough.
   Condition EmitTypeofIs(Label* true_label,
                          Label* false_label,
                          Register input,
                          Handle<String> type_name);
 
   // Emits optimized code for %_IsObject(x).  Preserves input register.
   // Returns the condition on which a final split to
@@ skipping 69 matching lines @@
   int inlined_function_count_;
   Scope* const scope_;
   Status status_;
   TranslationBuffer translations_;
   ZoneList<LDeferredCode*> deferred_;
   bool dynamic_frame_alignment_;
   bool support_aligned_spilled_doubles_;
   int osr_pc_offset_;
   int last_lazy_deopt_pc_;
   bool frame_is_built_;
+  int x87_stack_depth_;
 
   // Builder that keeps track of safepoints in the code. The table
   // itself is emitted at the end of the generated code.
   SafepointTableBuilder safepoints_;
 
   // Compiler from a set of parallel moves to a sequential list of moves.
   LGapResolver resolver_;
 
   Safepoint::Kind expected_safepoint_kind_;
 
@@ skipping 50 matching lines @@
   LCodeGen* codegen_;
   Label entry_;
   Label exit_;
   Label* external_exit_;
   int instruction_index_;
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_IA32_LITHIUM_CODEGEN_IA32_H_