Index: src/x64/virtual-frame-x64.h |
=================================================================== |
--- src/x64/virtual-frame-x64.h (revision 1881) |
+++ src/x64/virtual-frame-x64.h (working copy) |
@@ -25,3 +25,469 @@ |
// (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_X64_VIRTUAL_FRAME_X64_H_ |
+#define V8_X64_VIRTUAL_FRAME_X64_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(rsp, 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(rbp, 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(rbp, (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_X64_VIRTUAL_FRAME_X64_H_ |