text: // Copyright 2010 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
  //       with the distribution.
  //     * Neither the name of Google Inc. nor the names of its
  //       contributors may be used to endorse or promote products derived
  //       from this software without specific prior written permission.
  //
  // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  
  #ifndef V8_IA32_CODEGEN_IA32_H_
  #define V8_IA32_CODEGEN_IA32_H_
  
  #include "ast.h"
  #include "ic-inl.h"
  #include "jump-target-heavy.h"
  
  namespace v8 {
  namespace internal {
  
  // Forward declarations
  class CompilationInfo;
  class DeferredCode;
  class FrameRegisterState;
  class RegisterAllocator;
  class RegisterFile;
  class RuntimeCallHelper;
  
  enum InitState { CONST_INIT, NOT_CONST_INIT };
  enum TypeofState { INSIDE_TYPEOF, NOT_INSIDE_TYPEOF };
  
  
  // -------------------------------------------------------------------------
  // Reference support
  
  // A reference is a C++ stack-allocated object that puts a
  // reference on the virtual frame.  The reference may be consumed
  // by GetValue, TakeValue and SetValue.
  // When the lifetime (scope) of a valid reference ends, it must have
  // been consumed, and be in state UNLOADED.
  class Reference BASE_EMBEDDED {
   public:
    // The values of the types is important, see size().
    enum Type { UNLOADED = -2, ILLEGAL = -1, SLOT = 0, NAMED = 1, KEYED = 2 };
    Reference(CodeGenerator* cgen,
              Expression* expression,
              bool persist_after_get = false);
    ~Reference();
  
    Expression* expression() const { return expression_; }
    Type type() const { return type_; }
    void set_type(Type value) {
      ASSERT_EQ(ILLEGAL, type_);
      type_ = value;
    }
  
    void set_unloaded() {
      ASSERT_NE(ILLEGAL, type_);
      ASSERT_NE(UNLOADED, type_);
      type_ = UNLOADED;
    }
    // The size the reference takes up on the stack.
    int size() const {
      return (type_ < SLOT) ? 0 : type_;
    }
  
    bool is_illegal() const { return type_ == ILLEGAL; }
    bool is_slot() const { return type_ == SLOT; }
    bool is_property() const { return type_ == NAMED || type_ == KEYED; }
    bool is_unloaded() const { return type_ == UNLOADED; }
  
    // Return the name.  Only valid for named property references.
    Handle<String> GetName();
  
    // Generate code to push the value of the reference on top of the
    // expression stack.  The reference is expected to be already on top of
    // the expression stack, and it is consumed by the call unless the
    // reference is for a compound assignment.
    // If the reference is not consumed, it is left in place under its value.
    void GetValue();
  
    // Like GetValue except that the slot is expected to be written to before
    // being read from again.  The value of the reference may be invalidated,
    // causing subsequent attempts to read it to fail.
    void TakeValue();
  
    // Generate code to store the value on top of the expression stack in the
    // reference.  The reference is expected to be immediately below the value
    // on the expression stack.  The  value is stored in the location specified
    // by the reference, and is left on top of the stack, after the reference
    // is popped from beneath it (unloaded).
    void SetValue(InitState init_state);
  
   private:
    CodeGenerator* cgen_;
    Expression* expression_;
    Type type_;
    // Keep the reference on the stack after get, so it can be used by set later.
    bool persist_after_get_;
  };
  
  
  // -------------------------------------------------------------------------
  // Control destinations.
  
  // A control destination encapsulates a pair of jump targets and a
  // flag indicating which one is the preferred fall-through.  The
  // preferred fall-through must be unbound, the other may be already
  // bound (ie, a backward target).
  //
  // The true and false targets may be jumped to unconditionally or
  // control may split conditionally.  Unconditional jumping and
  // splitting should be emitted in tail position (as the last thing
  // when compiling an expression) because they can cause either label
  // to be bound or the non-fall through to be jumped to leaving an
  // invalid virtual frame.
  //
  // The labels in the control destination can be extracted and
  // manipulated normally without affecting the state of the
  // destination.
  
  class ControlDestination BASE_EMBEDDED {
   public:
    ControlDestination(JumpTarget* true_target,
                       JumpTarget* false_target,
                       bool true_is_fall_through)
        : true_target_(true_target),
          false_target_(false_target),
          true_is_fall_through_(true_is_fall_through),
          is_used_(false) {
      ASSERT(true_is_fall_through ? !true_target->is_bound()
                                  : !false_target->is_bound());
    }
  
    // Accessors for the jump targets.  Directly jumping or branching to
    // or binding the targets will not update the destination's state.
    JumpTarget* true_target() const { return true_target_; }
    JumpTarget* false_target() const { return false_target_; }
  
    // True if the the destination has been jumped to unconditionally or
    // control has been split to both targets.  This predicate does not
    // test whether the targets have been extracted and manipulated as
    // raw jump targets.
    bool is_used() const { return is_used_; }
  
    // True if the destination is used and the true target (respectively
    // false target) was the fall through.  If the target is backward,
    // "fall through" included jumping unconditionally to it.
    bool true_was_fall_through() const {
      return is_used_ && true_is_fall_through_;
    }
  
    bool false_was_fall_through() const {
      return is_used_ && !true_is_fall_through_;
    }
  
    // Emit a branch to one of the true or false targets, and bind the
    // other target.  Because this binds the fall-through target, it
    // should be emitted in tail position (as the last thing when
    // compiling an expression).
    void Split(Condition cc) {
      ASSERT(!is_used_);
      if (true_is_fall_through_) {
        false_target_->Branch(NegateCondition(cc));
        true_target_->Bind();
      } else {
        true_target_->Branch(cc);
        false_target_->Bind();
      }
      is_used_ = true;
    }
  
    // Emit an unconditional jump in tail position, to the true target
    // (if the argument is true) or the false target.  The "jump" will
    // actually bind the jump target if it is forward, jump to it if it
    // is backward.
    void Goto(bool where) {
      ASSERT(!is_used_);
      JumpTarget* target = where ? true_target_ : false_target_;
      if (target->is_bound()) {
        target->Jump();
      } else {
        target->Bind();
      }
      is_used_ = true;
      true_is_fall_through_ = where;
    }
  
    // Mark this jump target as used as if Goto had been called, but
    // without generating a jump or binding a label (the control effect
    // should have already happened).  This is used when the left
    // subexpression of the short-circuit boolean operators are
    // compiled.
    void Use(bool where) {
      ASSERT(!is_used_);
      ASSERT((where ? true_target_ : false_target_)->is_bound());
      is_used_ = true;
      true_is_fall_through_ = where;
    }
  
    // Swap the true and false targets but keep the same actual label as
    // the fall through.  This is used when compiling negated
    // expressions, where we want to swap the targets but preserve the
    // state.
    void Invert() {
      JumpTarget* temp_target = true_target_;
      true_target_ = false_target_;
      false_target_ = temp_target;
  
      true_is_fall_through_ = !true_is_fall_through_;
    }
  
   private:
    // True and false jump targets.
    JumpTarget* true_target_;
    JumpTarget* false_target_;
  
    // Before using the destination: true if the true target is the
    // preferred fall through, false if the false target is.  After
    // using the destination: true if the true target was actually used
    // as the fall through, false if the false target was.
    bool true_is_fall_through_;
  
    // True if the Split or Goto functions have been called.
    bool is_used_;
  };
  
  
  // -------------------------------------------------------------------------
  // Code generation state
  
  // The state is passed down the AST by the code generator (and back up, in
  // the form of the state of the jump target pair).  It is threaded through
  // the call stack.  Constructing a state implicitly pushes it on the owning
  // code generator's stack of states, and destroying one implicitly pops it.
  //
  // The code generator state is only used for expressions, so statements have
  // the initial state.
  
  class CodeGenState BASE_EMBEDDED {
   public:
    // Create an initial code generator state.  Destroying the initial state
    // leaves the code generator with a NULL state.
    explicit CodeGenState(CodeGenerator* owner);
  
    // Create a code generator state based on a code generator's current
    // state.  The new state has its own control destination.
    CodeGenState(CodeGenerator* owner, ControlDestination* destination);
  
    // Destroy a code generator state and restore the owning code generator's
    // previous state.
    ~CodeGenState();
  
    // Accessors for the state.
    ControlDestination* destination() const { return destination_; }
  
   private:
    // The owning code generator.
    CodeGenerator* owner_;
  
    // A control destination in case the expression has a control-flow
    // effect.
    ControlDestination* destination_;
  
    // The previous state of the owning code generator, restored when
    // this state is destroyed.
    CodeGenState* previous_;
  };
  
  
  // -------------------------------------------------------------------------
  // Arguments allocation mode.
  
  enum ArgumentsAllocationMode {
    NO_ARGUMENTS_ALLOCATION,
    EAGER_ARGUMENTS_ALLOCATION,
    LAZY_ARGUMENTS_ALLOCATION
  };
  
  
  // -------------------------------------------------------------------------
  // CodeGenerator
  
  class CodeGenerator: public AstVisitor {
   public:
    static bool MakeCode(CompilationInfo* info);
  
    // Printing of AST, etc. as requested by flags.
    static void MakeCodePrologue(CompilationInfo* info);
  
    // Allocate and install the code.
    static Handle<Code> MakeCodeEpilogue(MacroAssembler* masm,
                                         Code::Flags flags,
                                         CompilationInfo* info);
  
  #ifdef ENABLE_LOGGING_AND_PROFILING
    static bool ShouldGenerateLog(Expression* type);
  #endif
  
    static bool RecordPositions(MacroAssembler* masm,
                                int pos,
                                bool right_here = false);
  
    // Accessors
    MacroAssembler* masm() { return masm_; }
    VirtualFrame* frame() const { return frame_; }
    inline Handle<Script> script();
  
    bool has_valid_frame() const { return frame_ != NULL; }
  
    // Set the virtual frame to be new_frame, with non-frame register
    // reference counts given by non_frame_registers.  The non-frame
    // register reference counts of the old frame are returned in
    // non_frame_registers.
    void SetFrame(VirtualFrame* new_frame, RegisterFile* non_frame_registers);
  
    void DeleteFrame();
  
    RegisterAllocator* allocator() const { return allocator_; }
  
    CodeGenState* state() { return state_; }
    void set_state(CodeGenState* state) { state_ = state; }
  
    void AddDeferred(DeferredCode* code) { deferred_.Add(code); }
  
    bool in_spilled_code() const { return in_spilled_code_; }
    void set_in_spilled_code(bool flag) { in_spilled_code_ = flag; }
  
    // Return a position of the element at |index_as_smi| + |additional_offset|
    // in FixedArray pointer to which is held in |array|.  |index_as_smi| is Smi.
    static Operand FixedArrayElementOperand(Register array,
                                            Register index_as_smi,
                                            int additional_offset = 0) {
      int offset = FixedArray::kHeaderSize + additional_offset * kPointerSize;
      return FieldOperand(array, index_as_smi, times_half_pointer_size, offset);
    }
  
   private:
    // Type of a member function that generates inline code for a native function.
    typedef void (CodeGenerator::*InlineFunctionGenerator)
        (ZoneList<Expression*>*);
  
    static const InlineFunctionGenerator kInlineFunctionGenerators[];
  
    // Construction/Destruction
    explicit CodeGenerator(MacroAssembler* masm);
  
    // Accessors
    inline bool is_eval();
    inline Scope* scope();
  
    // Generating deferred code.
    void ProcessDeferred();
  
    // State
    ControlDestination* destination() const { return state_->destination(); }
  
    // Control of side-effect-free int32 expression compilation.
    bool in_safe_int32_mode() { return in_safe_int32_mode_; }
    void set_in_safe_int32_mode(bool value) { in_safe_int32_mode_ = value; }
    bool safe_int32_mode_enabled() {
      return FLAG_safe_int32_compiler && safe_int32_mode_enabled_;
    }
    void set_safe_int32_mode_enabled(bool value) {
      safe_int32_mode_enabled_ = value;
    }
    void set_unsafe_bailout(BreakTarget* unsafe_bailout) {
      unsafe_bailout_ = unsafe_bailout;
    }
  
    // Take the Result that is an untagged int32, and convert it to a tagged
    // Smi or HeapNumber.  Remove the untagged_int32 flag from the result.
    void ConvertInt32ResultToNumber(Result* value);
    void ConvertInt32ResultToSmi(Result* value);
  
    // Track loop nesting level.
    int loop_nesting() const { return loop_nesting_; }
    void IncrementLoopNesting() { loop_nesting_++; }
    void DecrementLoopNesting() { loop_nesting_--; }
  
    // Node visitors.
    void VisitStatements(ZoneList<Statement*>* statements);
  
  #define DEF_VISIT(type) \
    void Visit##type(type* node);
    AST_NODE_LIST(DEF_VISIT)
  #undef DEF_VISIT
  
    // Visit a statement and then spill the virtual frame if control flow can
    // reach the end of the statement (ie, it does not exit via break,
    // continue, return, or throw).  This function is used temporarily while
    // the code generator is being transformed.
    void VisitAndSpill(Statement* statement);
  
    // Visit a list of statements and then spill the virtual frame if control
    // flow can reach the end of the list.
    void VisitStatementsAndSpill(ZoneList<Statement*>* statements);
  
    // Main code generation function
    void Generate(CompilationInfo* info);
  
    // Generate the return sequence code.  Should be called no more than
    // once per compiled function, immediately after binding the return
    // target (which can not be done more than once).
    void GenerateReturnSequence(Result* return_value);
  
    // Returns the arguments allocation mode.
    ArgumentsAllocationMode ArgumentsMode();
  
    // Store the arguments object and allocate it if necessary.
    Result StoreArgumentsObject(bool initial);
  
    // The following are used by class Reference.
    void LoadReference(Reference* ref);
  
    Operand SlotOperand(Slot* slot, Register tmp);
  
    Operand ContextSlotOperandCheckExtensions(Slot* slot,
                                              Result tmp,
                                              JumpTarget* slow);
  
    // Expressions
    void LoadCondition(Expression* expr,
                       ControlDestination* destination,
                       bool force_control);
    void Load(Expression* expr);
    void LoadGlobal();
    void LoadGlobalReceiver();
  
    // Generate code to push the value of an expression on top of the frame
    // and then spill the frame fully to memory.  This function is used
    // temporarily while the code generator is being transformed.
    void LoadAndSpill(Expression* expression);
  
    // Evaluate an expression and place its value on top of the frame,
    // using, or not using, the side-effect-free expression compiler.
    void LoadInSafeInt32Mode(Expression* expr, BreakTarget* unsafe_bailout);
    void LoadWithSafeInt32ModeDisabled(Expression* expr);
  
    // Read a value from a slot and leave it on top of the expression stack.
    void LoadFromSlot(Slot* slot, TypeofState typeof_state);
    void LoadFromSlotCheckForArguments(Slot* slot, TypeofState typeof_state);
    Result LoadFromGlobalSlotCheckExtensions(Slot* slot,
                                             TypeofState typeof_state,
                                             JumpTarget* slow);
  
    // Support for loading from local/global variables and arguments
    // whose location is known unless they are shadowed by
    // eval-introduced bindings. Generates no code for unsupported slot
    // types and therefore expects to fall through to the slow jump target.
    void EmitDynamicLoadFromSlotFastCase(Slot* slot,
                                         TypeofState typeof_state,
                                         Result* result,
                                         JumpTarget* slow,
                                         JumpTarget* done);
  
    // Store the value on top of the expression stack into a slot, leaving the
    // value in place.
    void StoreToSlot(Slot* slot, InitState init_state);
  
    // Support for compiling assignment expressions.
    void EmitSlotAssignment(Assignment* node);
    void EmitNamedPropertyAssignment(Assignment* node);
    void EmitKeyedPropertyAssignment(Assignment* node);
  
    // Receiver is passed on the frame and consumed.
    Result EmitNamedLoad(Handle<String> name, bool is_contextual);
  
    // If the store is contextual, value is passed on the frame and consumed.
    // Otherwise, receiver and value are passed on the frame and consumed.
    Result EmitNamedStore(Handle<String> name, bool is_contextual);
  
    // Receiver and key are passed on the frame and consumed.
    Result EmitKeyedLoad();
  
    // Receiver, key, and value are passed on the frame and consumed.
    Result EmitKeyedStore(StaticType* key_type);
  
    // Special code for typeof expressions: Unfortunately, we must
    // be careful when loading the expression in 'typeof'
    // expressions. We are not allowed to throw reference errors for
    // non-existing properties of the global object, so we must make it
    // look like an explicit property access, instead of an access
    // through the context chain.
    void LoadTypeofExpression(Expression* x);
  
    // Translate the value on top of the frame into control flow to the
    // control destination.
    void ToBoolean(ControlDestination* destination);
  
    // Generate code that computes a shortcutting logical operation.
    void GenerateLogicalBooleanOperation(BinaryOperation* node);
  
    void GenericBinaryOperation(BinaryOperation* expr,
                                OverwriteMode overwrite_mode);
  
    // Emits code sequence that jumps to a JumpTarget if the inputs
    // are both smis.  Cannot be in MacroAssembler because it takes
    // advantage of TypeInfo to skip unneeded checks.
    // Allocates a temporary register, possibly spilling from the frame,
    // if it needs to check both left and right.
    void JumpIfBothSmiUsingTypeInfo(Result* left,
                                    Result* right,
                                    JumpTarget* both_smi);
  
    // Emits code sequence that jumps to deferred code if the inputs
    // are not both smis.  Cannot be in MacroAssembler because it takes
    // a deferred code object.
    void JumpIfNotBothSmiUsingTypeInfo(Register left,
                                       Register right,
                                       Register scratch,
                                       TypeInfo left_info,
                                       TypeInfo right_info,
                                       DeferredCode* deferred);
  
    // Emits code sequence that jumps to the label if the inputs
    // are not both smis.
    void JumpIfNotBothSmiUsingTypeInfo(Register left,
                                       Register right,
                                       Register scratch,
                                       TypeInfo left_info,
                                       TypeInfo right_info,
                                       Label* on_non_smi);
  
    // If possible, combine two constant smi values using op to produce
    // a smi result, and push it on the virtual frame, all at compile time.
    // Returns true if it succeeds.  Otherwise it has no effect.
    bool FoldConstantSmis(Token::Value op, int left, int right);
  
    // Emit code to perform a binary operation on a constant
    // smi and a likely smi.  Consumes the Result operand.
    Result ConstantSmiBinaryOperation(BinaryOperation* expr,
                                      Result* operand,
                                      Handle<Object> constant_operand,
                                      bool reversed,
                                      OverwriteMode overwrite_mode);
  
    // Emit code to perform a binary operation on two likely smis.
    // The code to handle smi arguments is produced inline.
    // Consumes the Results left and right.
    Result LikelySmiBinaryOperation(BinaryOperation* expr,
                                    Result* left,
                                    Result* right,
                                    OverwriteMode overwrite_mode);
  
  
    // Emit code to perform a binary operation on two untagged int32 values.
    // The values are on top of the frame, and the result is pushed on the frame.
    void Int32BinaryOperation(BinaryOperation* node);
  
  
    // Generate a stub call from the virtual frame.
    Result GenerateGenericBinaryOpStubCall(GenericBinaryOpStub* stub,
                                           Result* left,
                                           Result* right);
  
    void Comparison(AstNode* node,
                    Condition cc,
                    bool strict,
                    ControlDestination* destination);
  
    // If at least one of the sides is a constant smi, generate optimized code.
    void ConstantSmiComparison(Condition cc,
                               bool strict,
                               ControlDestination* destination,
                               Result* left_side,
                               Result* right_side,
                               bool left_side_constant_smi,
                               bool right_side_constant_smi,
                               bool is_loop_condition);
  
    void GenerateInlineNumberComparison(Result* left_side,
                                        Result* right_side,
                                        Condition cc,
                                        ControlDestination* dest);
  
    // To prevent long attacker-controlled byte sequences, integer constants
    // from the JavaScript source are loaded in two parts if they are larger
    // than 17 bits.
    static const int kMaxSmiInlinedBits = 17;
    bool IsUnsafeSmi(Handle<Object> value);
    // Load an integer constant x into a register target or into the stack using
    // at most 16 bits of user-controlled data per assembly operation.
    void MoveUnsafeSmi(Register target, Handle<Object> value);
    void StoreUnsafeSmiToLocal(int offset, Handle<Object> value);
    void PushUnsafeSmi(Handle<Object> value);
  
    void CallWithArguments(ZoneList<Expression*>* arguments,
                           CallFunctionFlags flags,
                           int position);
  
    // An optimized implementation of expressions of the form
    // x.apply(y, arguments).  We call x the applicand and y the receiver.
    // The optimization avoids allocating an arguments object if possible.
    void CallApplyLazy(Expression* applicand,
                       Expression* receiver,
                       VariableProxy* arguments,
                       int position);
  
    void CheckStack();
  
    bool CheckForInlineRuntimeCall(CallRuntime* node);
  
    void ProcessDeclarations(ZoneList<Declaration*>* declarations);
  
    // Declare global variables and functions in the given array of
    // name/value pairs.
    void DeclareGlobals(Handle<FixedArray> pairs);
  
    // Instantiate the function based on the shared function info.
    Result InstantiateFunction(Handle<SharedFunctionInfo> function_info,
                               bool pretenure);
  
    // Support for types.
    void GenerateIsSmi(ZoneList<Expression*>* args);
    void GenerateIsNonNegativeSmi(ZoneList<Expression*>* args);
    void GenerateIsArray(ZoneList<Expression*>* args);
    void GenerateIsRegExp(ZoneList<Expression*>* args);
    void GenerateIsObject(ZoneList<Expression*>* args);
    void GenerateIsSpecObject(ZoneList<Expression*>* args);
    void GenerateIsFunction(ZoneList<Expression*>* args);
    void GenerateIsUndetectableObject(ZoneList<Expression*>* args);
    void GenerateIsStringWrapperSafeForDefaultValueOf(
        ZoneList<Expression*>* args);
  
    // Support for construct call checks.
    void GenerateIsConstructCall(ZoneList<Expression*>* args);
  
    // Support for arguments.length and arguments[?].
    void GenerateArgumentsLength(ZoneList<Expression*>* args);
    void GenerateArguments(ZoneList<Expression*>* args);
  
    // Support for accessing the class and value fields of an object.
    void GenerateClassOf(ZoneList<Expression*>* args);
    void GenerateValueOf(ZoneList<Expression*>* args);
    void GenerateSetValueOf(ZoneList<Expression*>* args);
  
    // Fast support for charCodeAt(n).
    void GenerateStringCharCodeAt(ZoneList<Expression*>* args);
  
    // Fast support for string.charAt(n) and string[n].
    void GenerateStringCharFromCode(ZoneList<Expression*>* args);
  
    // Fast support for string.charAt(n) and string[n].
    void GenerateStringCharAt(ZoneList<Expression*>* args);
  
    // Fast support for object equality testing.
    void GenerateObjectEquals(ZoneList<Expression*>* args);
  
    void GenerateLog(ZoneList<Expression*>* args);
  
    void GenerateGetFramePointer(ZoneList<Expression*>* args);
  
    // Fast support for Math.random().
    void GenerateRandomHeapNumber(ZoneList<Expression*>* args);
  
    // Fast support for StringAdd.
    void GenerateStringAdd(ZoneList<Expression*>* args);
  
    // Fast support for SubString.
    void GenerateSubString(ZoneList<Expression*>* args);
  
    // Fast support for StringCompare.
    void GenerateStringCompare(ZoneList<Expression*>* args);
  
    // Support for direct calls from JavaScript to native RegExp code.
    void GenerateRegExpExec(ZoneList<Expression*>* args);
  
    // Construct a RegExp exec result with two in-object properties.
    void GenerateRegExpConstructResult(ZoneList<Expression*>* args);
  
    // Support for fast native caches.
    void GenerateGetFromCache(ZoneList<Expression*>* args);
  
    // Fast support for number to string.
    void GenerateNumberToString(ZoneList<Expression*>* args);
  
    // Fast swapping of elements. Takes three expressions, the object and two
    // indices. This should only be used if the indices are known to be
    // non-negative and within bounds of the elements array at the call site.
    void GenerateSwapElements(ZoneList<Expression*>* args);
  
    // Fast call for custom callbacks.
    void GenerateCallFunction(ZoneList<Expression*>* args);
  
    // Fast call to math functions.
    void GenerateMathPow(ZoneList<Expression*>* args);
    void GenerateMathSin(ZoneList<Expression*>* args);
    void GenerateMathCos(ZoneList<Expression*>* args);
    void GenerateMathSqrt(ZoneList<Expression*>* args);
  
    // Check whether two RegExps are equivalent
    void GenerateIsRegExpEquivalent(ZoneList<Expression*>* args);
  
    void GenerateHasCachedArrayIndex(ZoneList<Expression*>* args);
    void GenerateGetCachedArrayIndex(ZoneList<Expression*>* args);
    void GenerateFastAsciiArrayJoin(ZoneList<Expression*>* args);
  
    // Simple condition analysis.
    enum ConditionAnalysis {
      ALWAYS_TRUE,
      ALWAYS_FALSE,
      DONT_KNOW
    };
    ConditionAnalysis AnalyzeCondition(Expression* cond);
  
    // Methods used to indicate which source code is generated for. Source
    // positions are collected by the assembler and emitted with the relocation
    // information.
    void CodeForFunctionPosition(FunctionLiteral* fun);
    void CodeForReturnPosition(FunctionLiteral* fun);
    void CodeForStatementPosition(Statement* stmt);
    void CodeForDoWhileConditionPosition(DoWhileStatement* stmt);
    void CodeForSourcePosition(int pos);
  
    void SetTypeForStackSlot(Slot* slot, TypeInfo info);
  
  #ifdef DEBUG
    // True if the registers are valid for entry to a block.  There should
    // be no frame-external references to (non-reserved) registers.
    bool HasValidEntryRegisters();
  #endif
  
    ZoneList<DeferredCode*> deferred_;
  
    // Assembler
    MacroAssembler* masm_;  // to generate code
  
    CompilationInfo* info_;
  
    // Code generation state
    VirtualFrame* frame_;
    RegisterAllocator* allocator_;
    CodeGenState* state_;
    int loop_nesting_;
    bool in_safe_int32_mode_;
    bool safe_int32_mode_enabled_;
  
    // Jump targets.
    // The target of the return from the function.
    BreakTarget function_return_;
    // The target of the bailout from a side-effect-free int32 subexpression.
    BreakTarget* unsafe_bailout_;
  
    // True if the function return is shadowed (ie, jumping to the target
    // function_return_ does not jump to the true function return, but rather
    // to some unlinking code).
    bool function_return_is_shadowed_;
  
    // True when we are in code that expects the virtual frame to be fully
    // spilled.  Some virtual frame function are disabled in DEBUG builds when
    // called from spilled code, because they do not leave the virtual frame
    // in a spilled state.
    bool in_spilled_code_;
  
    // A cookie that is used for JIT IMM32 Encoding.  Initialized to a
    // random number when the command-line
    // FLAG_mask_constants_with_cookie is true, zero otherwise.
    int jit_cookie_;
  
    friend class VirtualFrame;
    friend class JumpTarget;
    friend class Reference;
    friend class Result;
    friend class FastCodeGenerator;
    friend class FullCodeGenerator;
    friend class FullCodeGenSyntaxChecker;
  
    friend class CodeGeneratorPatcher;  // Used in test-log-stack-tracer.cc
  
    DISALLOW_COPY_AND_ASSIGN(CodeGenerator);
  };
  
  
  } }  // namespace v8::internal
  
  #endif  // V8_IA32_CODEGEN_IA32_H_
  