Move backend specific files to separate directories.

src/virtual-frame-ia32.h

-// Copyright 2009 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_VIRTUAL_FRAME_IA32_H_
-#define V8_VIRTUAL_FRAME_IA32_H_
-
-#include "register-allocator.h"
-
-namespace v8 { namespace internal {
-
-// -------------------------------------------------------------------------
-// Virtual frames
-//
-// The virtual frame is an abstraction of the physical stack frame.  It
-// encapsulates the parameters, frame-allocated locals, and the expression
-// stack.  It supports push/pop operations on the expression stack, as well
-// as random access to the expression stack elements, locals, and
-// parameters.
-
-class VirtualFrame : public Malloced {
- public:
-  // A utility class to introduce a scope where the virtual frame is
-  // expected to remain spilled.  The constructor spills the code
-  // generator's current frame, but no attempt is made to require it
-  // to stay spilled.  It is intended as documentation while the code
-  // generator is being transformed.
-  class SpilledScope BASE_EMBEDDED {
-   public:
-    explicit SpilledScope(CodeGenerator* cgen);
-
-    ~SpilledScope();
-
-   private:
-    CodeGenerator* cgen_;
-    bool previous_state_;
-  };
-
-  // An illegal index into the virtual frame.
-  static const int kIllegalIndex = -1;
-
-  // Construct an initial virtual frame on entry to a JS function.
-  explicit VirtualFrame(CodeGenerator* cgen);
-
-  // Construct a virtual frame as a clone of an existing one.
-  explicit VirtualFrame(VirtualFrame* original);
-
-  // Create a duplicate of an existing valid frame element.
-  FrameElement CopyElementAt(int index);
-
-  // The height of the virtual expression stack.
-  int height() const {
-    return elements_.length() - expression_base_index();
-  }
-
-  int register_index(Register reg) {
-    return register_locations_[reg.code()];
-  }
-
-  bool is_used(int reg_code) {
-    return register_locations_[reg_code] != kIllegalIndex;
-  }
-
-  bool is_used(Register reg) {
-    return is_used(reg.code());
-  }
-
-  // Add extra in-memory elements to the top of the frame to match an actual
-  // frame (eg, the frame after an exception handler is pushed).  No code is
-  // emitted.
-  void Adjust(int count);
-
-  // Forget count elements from the top of the frame all in-memory
-  // (including synced) and adjust the stack pointer downward, to
-  // match an external frame effect (examples include a call removing
-  // its arguments, and exiting a try/catch removing an exception
-  // handler).  No code will be emitted.
-  void Forget(int count);
-
-  // Forget count elements from the top of the frame without adjusting
-  // the stack pointer downward.  This is used, for example, before
-  // merging frames at break, continue, and return targets.
-  void ForgetElements(int count);
-
-  // Spill all values from the frame to memory.
-  void SpillAll();
-
-  // Spill all occurrences of a specific register from the frame.
-  void Spill(Register reg);
-
-  // Spill all occurrences of an arbitrary register if possible.  Return the
-  // register spilled or no_reg if it was not possible to free any register
-  // (ie, they all have frame-external references).
-  Register SpillAnyRegister();
-
-  // Prepare this virtual frame for merging to an expected frame by
-  // performing some state changes that do not require generating
-  // code.  It is guaranteed that no code will be generated.
-  void PrepareMergeTo(VirtualFrame* expected);
-
-  // Make this virtual frame have a state identical to an expected virtual
-  // frame.  As a side effect, code may be emitted to make this frame match
-  // the expected one.
-  void MergeTo(VirtualFrame* expected);
-
-  // Detach a frame from its code generator, perhaps temporarily.  This
-  // tells the register allocator that it is free to use frame-internal
-  // registers.  Used when the code generator's frame is switched from this
-  // one to NULL by an unconditional jump.
-  void DetachFromCodeGenerator();
-
-  // (Re)attach a frame to its code generator.  This informs the register
-  // allocator that the frame-internal register references are active again.
-  // Used when a code generator's frame is switched from NULL to this one by
-  // binding a label.
-  void AttachToCodeGenerator();
-
-  // Emit code for the physical JS entry and exit frame sequences.  After
-  // calling Enter, the virtual frame is ready for use; and after calling
-  // Exit it should not be used.  Note that Enter does not allocate space in
-  // the physical frame for storing frame-allocated locals.
-  void Enter();
-  void Exit();
-
-  // Prepare for returning from the frame by spilling locals.  This
-  // avoids generating unnecessary merge code when jumping to the
-  // shared return site.  Emits code for spills.
-  void PrepareForReturn();
-
-  // Allocate and initialize the frame-allocated locals.
-  void AllocateStackSlots(int count);
-
-  // An element of the expression stack as an assembly operand.
-  Operand ElementAt(int index) const {
-    return Operand(esp, index * kPointerSize);
-  }
-
-  // Random-access store to a frame-top relative frame element.  The result
-  // becomes owned by the frame and is invalidated.
-  void SetElementAt(int index, Result* value);
-
-  // Set a frame element to a constant.  The index is frame-top relative.
-  void SetElementAt(int index, Handle<Object> value) {
-    Result temp(value, cgen_);
-    SetElementAt(index, &temp);
-  }
-
-  void PushElementAt(int index) {
-    PushFrameSlotAt(elements_.length() - index - 1);
-  }
-
-  void StoreToElementAt(int index) {
-    StoreToFrameSlotAt(elements_.length() - index - 1);
-  }
-
-  // A frame-allocated local as an assembly operand.
-  Operand LocalAt(int index) const {
-    ASSERT(0 <= index);
-    ASSERT(index < local_count_);
-    return Operand(ebp, kLocal0Offset - index * kPointerSize);
-  }
-
-  // Push a copy of the value of a local frame slot on top of the frame.
-  void PushLocalAt(int index) {
-    PushFrameSlotAt(local0_index() + index);
-  }
-
-  // Push the value of a local frame slot on top of the frame and invalidate
-  // the local slot.  The slot should be written to before trying to read
-  // from it again.
-  void TakeLocalAt(int index) {
-    TakeFrameSlotAt(local0_index() + index);
-  }
-
-  // Store the top value on the virtual frame into a local frame slot.  The
-  // value is left in place on top of the frame.
-  void StoreToLocalAt(int index) {
-    StoreToFrameSlotAt(local0_index() + index);
-  }
-
-  // Push the address of the receiver slot on the frame.
-  void PushReceiverSlotAddress();
-
-  // Push the function on top of the frame.
-  void PushFunction() { PushFrameSlotAt(function_index()); }
-
-  // Save the value of the esi register to the context frame slot.
-  void SaveContextRegister();
-
-  // Restore the esi register from the value of the context frame
-  // slot.
-  void RestoreContextRegister();
-
-  // A parameter as an assembly operand.
-  Operand ParameterAt(int index) const {
-    ASSERT(-1 <= index);  // -1 is the receiver.
-    ASSERT(index < parameter_count_);
-    return Operand(ebp, (1 + parameter_count_ - index) * kPointerSize);
-  }
-
-  // Push a copy of the value of a parameter frame slot on top of the frame.
-  void PushParameterAt(int index) {
-    PushFrameSlotAt(param0_index() + index);
-  }
-
-  // Push the value of a paramter frame slot on top of the frame and
-  // invalidate the parameter slot.  The slot should be written to before
-  // trying to read from it again.
-  void TakeParameterAt(int index) {
-    TakeFrameSlotAt(param0_index() + index);
-  }
-
-  // Store the top value on the virtual frame into a parameter frame slot.
-  // The value is left in place on top of the frame.
-  void StoreToParameterAt(int index) {
-    StoreToFrameSlotAt(param0_index() + index);
-  }
-
-  // The receiver frame slot.
-  Operand Receiver() const { return ParameterAt(-1); }
-
-  // Push a try-catch or try-finally handler on top of the virtual frame.
-  void PushTryHandler(HandlerType type);
-
-  // Call stub given the number of arguments it expects on (and
-  // removes from) the stack.
-  Result CallStub(CodeStub* stub, int arg_count);
-
-  // Call stub that takes a single argument passed in eax.  The
-  // argument is given as a result which does not have to be eax or
-  // even a register.  The argument is consumed by the call.
-  Result CallStub(CodeStub* stub, Result* arg);
-
-  // Call stub that takes a pair of arguments passed in edx (arg0) and
-  // eax (arg1).  The arguments are given as results which do not have
-  // to be in the proper registers or even in registers.  The
-  // arguments are consumed by the call.
-  Result CallStub(CodeStub* stub, Result* arg0, Result* arg1);
-
-  // Call runtime given the number of arguments expected on (and
-  // removed from) the stack.
-  Result CallRuntime(Runtime::Function* f, int arg_count);
-  Result CallRuntime(Runtime::FunctionId id, int arg_count);
-
-  // Invoke builtin given the number of arguments it expects on (and
-  // removes from) the stack.
-  Result InvokeBuiltin(Builtins::JavaScript id,
-                       InvokeFlag flag,
-                       int arg_count);
-
-  // Call load IC.  Name and receiver are found on top of the frame.
-  // Receiver is not dropped.
-  Result CallLoadIC(RelocInfo::Mode mode);
-
-  // Call keyed load IC.  Key and receiver are found on top of the
-  // frame.  They are not dropped.
-  Result CallKeyedLoadIC(RelocInfo::Mode mode);
-
-  // Call store IC.  Name, value, and receiver are found on top of the
-  // frame.  Receiver is not dropped.
-  Result CallStoreIC();
-
-  // Call keyed store IC.  Value, key, and receiver are found on top
-  // of the frame.  Key and receiver are not dropped.
-  Result CallKeyedStoreIC();
-
-  // Call call IC.  Arguments, reciever, and function name are found
-  // on top of the frame.  Function name slot is not dropped.  The
-  // argument count does not include the receiver.
-  Result CallCallIC(RelocInfo::Mode mode, int arg_count, int loop_nesting);
-
-  // Allocate and call JS function as constructor.  Arguments,
-  // receiver (global object), and function are found on top of the
-  // frame.  Function is not dropped.  The argument count does not
-  // include the receiver.
-  Result CallConstructor(int arg_count);
-
-  // Drop a number of elements from the top of the expression stack.  May
-  // emit code to affect the physical frame.  Does not clobber any registers
-  // excepting possibly the stack pointer.
-  void Drop(int count);
-
-  // Drop one element.
-  void Drop() { Drop(1); }
-
-  // Duplicate the top element of the frame.
-  void Dup() { PushFrameSlotAt(elements_.length() - 1); }
-
-  // Pop an element from the top of the expression stack.  Returns a
-  // Result, which may be a constant or a register.
-  Result Pop();
-
-  // Pop and save an element from the top of the expression stack and
-  // emit a corresponding pop instruction.
-  void EmitPop(Register reg);
-  void EmitPop(Operand operand);
-
-  // Push an element on top of the expression stack and emit a
-  // corresponding push instruction.
-  void EmitPush(Register reg);
-  void EmitPush(Operand operand);
-  void EmitPush(Immediate immediate);
-
-  // Push an element on the virtual frame.
-  void Push(Register reg, StaticType static_type = StaticType());
-  void Push(Handle<Object> value);
-  void Push(Smi* value) { Push(Handle<Object>(value)); }
-
-  // Pushing a result invalidates it (its contents become owned by the
-  // frame).
-  void Push(Result* result);
-
-  // Nip removes zero or more elements from immediately below the top
-  // of the frame, leaving the previous top-of-frame value on top of
-  // the frame.  Nip(k) is equivalent to x = Pop(), Drop(k), Push(x).
-  void Nip(int num_dropped);
-
- private:
-  static const int kLocal0Offset = JavaScriptFrameConstants::kLocal0Offset;
-  static const int kFunctionOffset = JavaScriptFrameConstants::kFunctionOffset;
-  static const int kContextOffset = StandardFrameConstants::kContextOffset;
-
-  static const int kHandlerSize = StackHandlerConstants::kSize / kPointerSize;
-  static const int kPreallocatedElements = 5 + 8;  // 8 expression stack slots.
-
-  CodeGenerator* cgen_;
-  MacroAssembler* masm_;
-
-  List<FrameElement> elements_;
-
-  // The number of frame-allocated locals and parameters respectively.
-  int parameter_count_;
-  int local_count_;
-
-  // The index of the element that is at the processor's stack pointer
-  // (the esp register).
-  int stack_pointer_;
-
-  // The index of the element that is at the processor's frame pointer
-  // (the ebp register).
-  int frame_pointer_;
-
-  // The index of the register frame element using each register, or
-  // kIllegalIndex if a register is not on the frame.
-  int register_locations_[kNumRegisters];
-
-  // The index of the first parameter.  The receiver lies below the first
-  // parameter.
-  int param0_index() const { return 1; }
-
-  // The index of the context slot in the frame.
-  int context_index() const {
-    ASSERT(frame_pointer_ != kIllegalIndex);
-    return frame_pointer_ + 1;
-  }
-
-  // The index of the function slot in the frame.  It lies above the context
-  // slot.
-  int function_index() const {
-    ASSERT(frame_pointer_ != kIllegalIndex);
-    return frame_pointer_ + 2;
-  }
-
-  // The index of the first local.  Between the parameters and the locals
-  // lie the return address, the saved frame pointer, the context, and the
-  // function.
-  int local0_index() const {
-    ASSERT(frame_pointer_ != kIllegalIndex);
-    return frame_pointer_ + 3;
-  }
-
-  // The index of the base of the expression stack.
-  int expression_base_index() const { return local0_index() + local_count_; }
-
-  // Convert a frame index into a frame pointer relative offset into the
-  // actual stack.
-  int fp_relative(int index) const {
-    return (frame_pointer_ - index) * kPointerSize;
-  }
-
-  // Record an occurrence of a register in the virtual frame.  This has the
-  // effect of incrementing the register's external reference count and
-  // of updating the index of the register's location in the frame.
-  void Use(Register reg, int index);
-
-  // Record that a register reference has been dropped from the frame.  This
-  // decrements the register's external reference count and invalidates the
-  // index of the register's location in the frame.
-  void Unuse(Register reg);
-
-  // Spill the element at a particular index---write it to memory if
-  // necessary, free any associated register, and forget its value if
-  // constant.
-  void SpillElementAt(int index);
-
-  // Sync the element at a particular index.  If it is a register or
-  // constant that disagrees with the value on the stack, write it to memory.
-  // Keep the element type as register or constant, and clear the dirty bit.
-  void SyncElementAt(int index);
-
-  // Sync the range of elements in [begin, end).
-  void SyncRange(int begin, int end);
-
-  // Sync a single unsynced element that lies beneath or at the stack pointer.
-  void SyncElementBelowStackPointer(int index);
-
-  // Sync a single unsynced element that lies just above the stack pointer.
-  void SyncElementByPushing(int index);
-
-  // Push a copy of a frame slot (typically a local or parameter) on top of
-  // the frame.
-  void PushFrameSlotAt(int index);
-
-  // Push a the value of a frame slot (typically a local or parameter) on
-  // top of the frame and invalidate the slot.
-  void TakeFrameSlotAt(int index);
-
-  // Store the value on top of the frame to a frame slot (typically a local
-  // or parameter).
-  void StoreToFrameSlotAt(int index);
-
-  // Spill all elements in registers. Spill the top spilled_args elements
-  // on the frame.  Sync all other frame elements.
-  // Then drop dropped_args elements from the virtual frame, to match
-  // the effect of an upcoming call that will drop them from the stack.
-  void PrepareForCall(int spilled_args, int dropped_args);
-
-  // Move frame elements currently in registers or constants, that
-  // should be in memory in the expected frame, to memory.
-  void MergeMoveRegistersToMemory(VirtualFrame* expected);
-
-  // Make the register-to-register moves necessary to
-  // merge this frame with the expected frame.
-  // Register to memory moves must already have been made,
-  // and memory to register moves must follow this call.
-  // This is because some new memory-to-register moves are
-  // created in order to break cycles of register moves.
-  // Used in the implementation of MergeTo().
-  void MergeMoveRegistersToRegisters(VirtualFrame* expected);
-
-  // Make the memory-to-register and constant-to-register moves
-  // needed to make this frame equal the expected frame.
-  // Called after all register-to-memory and register-to-register
-  // moves have been made.  After this function returns, the frames
-  // should be equal.
-  void MergeMoveMemoryToRegisters(VirtualFrame* expected);
-
-  // Invalidates a frame slot (puts an invalid frame element in it).
-  // Copies on the frame are correctly handled, and if this slot was
-  // the backing store of copies, the index of the new backing store
-  // is returned.  Otherwise, returns kIllegalIndex.
-  // Register counts are correctly updated.
-  int InvalidateFrameSlotAt(int index);
-
-  // Call a code stub that has already been prepared for calling (via
-  // PrepareForCall).
-  Result RawCallStub(CodeStub* stub);
-
-  // Calls a code object which has already been prepared for calling
-  // (via PrepareForCall).
-  Result RawCallCodeObject(Handle<Code> code, RelocInfo::Mode rmode);
-
-  bool Equals(VirtualFrame* other);
-
-  friend class JumpTarget;
-};
-
-} }  // namespace v8::internal
-
-#endif  // V8_VIRTUAL_FRAME_IA32_H_