Revert revision 1949.

src/frame-element.h

Index: src/frame-element.h
===================================================================
--- src/frame-element.h	(revision 1949)
+++ src/frame-element.h	(working copy)
@@ -1,265 +0,0 @@
-// 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_FRAME_ELEMENT_H_
-#define V8_FRAME_ELEMENT_H_
-
-#include "register-allocator-inl.h"
-
-namespace v8 { namespace internal {
-
-// -------------------------------------------------------------------------
-// Virtual frame elements
-//
-// The internal elements of the virtual frames.  There are several kinds of
-// elements:
-//   * Invalid: elements that are uninitialized or not actually part
-//     of the virtual frame.  They should not be read.
-//   * Memory: an element that resides in the actual frame.  Its address is
-//     given by its position in the virtual frame.
-//   * Register: an element that resides in a register.
-//   * Constant: an element whose value is known at compile time.
-
-class FrameElement BASE_EMBEDDED {
- public:
-  enum SyncFlag {
-    NOT_SYNCED,
-    SYNCED
-  };
-
-  // The default constructor creates an invalid frame element.
-  FrameElement() {
-    value_ = StaticTypeField::encode(StaticType::UNKNOWN_TYPE)
-        | TypeField::encode(INVALID)
-        | CopiedField::encode(false)
-        | SyncedField::encode(false)
-        | DataField::encode(0);
-  }
-
-  // Factory function to construct an invalid frame element.
-  static FrameElement InvalidElement() {
-    FrameElement result;
-    return result;
-  }
-
-  // Factory function to construct an in-memory frame element.
-  static FrameElement MemoryElement() {
-    FrameElement result(MEMORY, no_reg, SYNCED);
-    return result;
-  }
-
-  // Factory function to construct an in-register frame element.
-  static FrameElement RegisterElement(Register reg,
-                                      SyncFlag is_synced,
-                                      StaticType static_type = StaticType()) {
-    return FrameElement(REGISTER, reg, is_synced, static_type);
-  }
-
-  // Factory function to construct a frame element whose value is known at
-  // compile time.
-  static FrameElement ConstantElement(Handle<Object> value,
-                                      SyncFlag is_synced) {
-    FrameElement result(value, is_synced);
-    return result;
-  }
-
-  // Static indirection table for handles to constants.  If a frame
-  // element represents a constant, the data contains an index into
-  // this table of handles to the actual constants.
-  typedef ZoneList<Handle<Object> > ZoneObjectList;
-
-  static ZoneObjectList* ConstantList() {
-    static ZoneObjectList list(10);
-    return &list;
-  }
-
-  // Clear the constants indirection table.
-  static void ClearConstantList() {
-    ConstantList()->Clear();
-  }
-
-  bool is_synced() const { return SyncedField::decode(value_); }
-
-  void set_sync() {
-    ASSERT(type() != MEMORY);
-    value_ = value_ | SyncedField::encode(true);
-  }
-
-  void clear_sync() {
-    ASSERT(type() != MEMORY);
-    value_ = value_ & ~SyncedField::mask();
-  }
-
-  bool is_valid() const { return type() != INVALID; }
-  bool is_memory() const { return type() == MEMORY; }
-  bool is_register() const { return type() == REGISTER; }
-  bool is_constant() const { return type() == CONSTANT; }
-  bool is_copy() const { return type() == COPY; }
-
-  bool is_copied() const { return CopiedField::decode(value_); }
-  void set_copied() { value_ = value_ | CopiedField::encode(true); }
-  void clear_copied() { value_ = value_ & ~CopiedField::mask(); }
-
-  Register reg() const {
-    ASSERT(is_register());
-    uint32_t reg = DataField::decode(value_);
-    Register result;
-    result.code_ = reg;
-    return result;
-  }
-
-  Handle<Object> handle() const {
-    ASSERT(is_constant());
-    return ConstantList()->at(DataField::decode(value_));
-  }
-
-  int index() const {
-    ASSERT(is_copy());
-    return DataField::decode(value_);
-  }
-
-  StaticType static_type() {
-    return StaticType(StaticTypeField::decode(value_));
-  }
-
-  void set_static_type(StaticType static_type) {
-    value_ = value_ & ~StaticTypeField::mask();
-    value_ = value_ | StaticTypeField::encode(static_type.static_type_);
-  }
-
-  bool Equals(FrameElement other) {
-    if (value_ == other.value_) return true;
-
-    if (type() != other.type() ||
-        is_copied() != other.is_copied() ||
-        is_synced() != other.is_synced()) return false;
-
-    if (is_register()) {
-      if (!reg().is(other.reg())) return false;
-    } else if (is_constant()) {
-      if (!handle().is_identical_to(other.handle())) return false;
-    } else if (is_copy()) {
-      if (index() != other.index()) return false;
-    }
-
-    return true;
-  }
-
-  // Given a pair of non-null frame element pointers, return one of them
-  // as an entry frame candidate or null if they are incompatible.
-  FrameElement* Combine(FrameElement* other) {
-    // If either is invalid, the result is.
-    if (!is_valid()) return this;
-    if (!other->is_valid()) return other;
-
-    // If they do not have the exact same location we reallocate.
-    bool not_same_location =
-        (type() != other->type()) ||
-        (is_register() && !reg().is(other->reg())) ||
-        (is_constant() && !handle().is_identical_to(other->handle())) ||
-        (is_copy() && index() != other->index());
-    if (not_same_location) return NULL;
-
-    // If either is unsynced, the result is.  The result static type is
-    // the merge of the static types.  It's safe to set it on one of the
-    // frame elements, and harmless too (because we are only going to
-    // merge the reaching frames and will ensure that the types are
-    // coherent, and changing the static type does not emit code).
-    FrameElement* result = is_synced() ? other : this;
-    result->set_static_type(static_type().merge(other->static_type()));
-    return result;
-  }
-
- private:
-  enum Type {
-    INVALID,
-    MEMORY,
-    REGISTER,
-    CONSTANT,
-    COPY
-  };
-
-  // Used to construct memory and register elements.
-  FrameElement(Type type, Register reg, SyncFlag is_synced) {
-    value_ = StaticTypeField::encode(StaticType::UNKNOWN_TYPE)
-        | TypeField::encode(type)
-        | CopiedField::encode(false)
-        | SyncedField::encode(is_synced != NOT_SYNCED)
-        | DataField::encode(reg.code_ > 0 ? reg.code_ : 0);
-  }
-
-  FrameElement(Type type, Register reg, SyncFlag is_synced, StaticType stype) {
-    value_ = StaticTypeField::encode(stype.static_type_)
-        | TypeField::encode(type)
-        | CopiedField::encode(false)
-        | SyncedField::encode(is_synced != NOT_SYNCED)
-        | DataField::encode(reg.code_ > 0 ? reg.code_ : 0);
-  }
-
-  // Used to construct constant elements.
-  FrameElement(Handle<Object> value, SyncFlag is_synced) {
-    value_ = StaticTypeField::encode(StaticType::TypeOf(*value).static_type_)
-        | TypeField::encode(CONSTANT)
-        | CopiedField::encode(false)
-        | SyncedField::encode(is_synced != NOT_SYNCED)
-        | DataField::encode(ConstantList()->length());
-    ConstantList()->Add(value);
-  }
-
-  Type type() const { return TypeField::decode(value_); }
-  void set_type(Type type) {
-    value_ = value_ & ~TypeField::mask();
-    value_ = value_ | TypeField::encode(type);
-  }
-
-  void set_index(int new_index) {
-    ASSERT(is_copy());
-    value_ = value_ & ~DataField::mask();
-    value_ = value_ | DataField::encode(new_index);
-  }
-
-  void set_reg(Register new_reg) {
-    ASSERT(is_register());
-    value_ = value_ & ~DataField::mask();
-    value_ = value_ | DataField::encode(new_reg.code_);
-  }
-
-  // Encode static type, type, copied, synced and data in one 32 bit integer.
-  uint32_t value_;
-
-  class StaticTypeField: public BitField<StaticType::StaticTypeEnum, 0, 3> {};
-  class TypeField: public BitField<Type, 3, 3> {};
-  class CopiedField: public BitField<uint32_t, 6, 1> {};
-  class SyncedField: public BitField<uint32_t, 7, 1> {};
-  class DataField: public BitField<uint32_t, 8, 32 - 9> {};
-
-  friend class VirtualFrame;
-};
-
-} }  // namespace v8::internal
-
-#endif  // V8_FRAME_ELEMENT_H_