[turbofan] cleanup InstructionOperand a little

src/compiler/instruction.h

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_COMPILER_INSTRUCTION_H_
 #define V8_COMPILER_INSTRUCTION_H_
 
 #include <deque>
 #include <iosfwd>
 #include <map>
 #include <set>
 
 #include "src/compiler/common-operator.h"
 #include "src/compiler/frame.h"
 #include "src/compiler/instruction-codes.h"
 #include "src/compiler/opcodes.h"
 #include "src/compiler/register-configuration.h"
 #include "src/compiler/source-position.h"
 #include "src/zone-allocator.h"
 
 namespace v8 {
 namespace internal {
 namespace compiler {
 
 class Schedule;
 
 // A couple of reserved opcodes are used for internal use.
 const InstructionCode kSourcePositionInstruction = -1;
 
-#define INSTRUCTION_OPERAND_LIST(V)     \
-  V(Constant, CONSTANT)                 \
-  V(Immediate, IMMEDIATE)               \
+#define ALLOCATED_OPERAND_LIST(V)       \
   V(StackSlot, STACK_SLOT)              \
   V(DoubleStackSlot, DOUBLE_STACK_SLOT) \
   V(Register, REGISTER)                 \
   V(DoubleRegister, DOUBLE_REGISTER)
 
 class InstructionOperand {
  public:
   static const int kInvalidVirtualRegister = -1;
 
   enum Kind {
     INVALID,
     UNALLOCATED,
     CONSTANT,
     IMMEDIATE,
     STACK_SLOT,
     DOUBLE_STACK_SLOT,
     REGISTER,
     DOUBLE_REGISTER
   };
 
-  InstructionOperand() { ConvertTo(INVALID, 0, kInvalidVirtualRegister); }
-
-  InstructionOperand(Kind kind, int index) {
-    DCHECK(kind != UNALLOCATED && kind != INVALID);
-    ConvertTo(kind, index, kInvalidVirtualRegister);
-  }
-
-  static InstructionOperand* New(Zone* zone, Kind kind, int index) {
-    return New(zone, InstructionOperand(kind, index));
-  }
+  InstructionOperand()
+      : InstructionOperand(INVALID, 0, kInvalidVirtualRegister) {}
 
   Kind kind() const { return KindField::decode(value_); }
-  // TODO(dcarney): move this to subkind operand.
-  int index() const {
-    DCHECK(kind() != UNALLOCATED && kind() != INVALID);
-    return static_cast<int64_t>(value_) >> IndexField::kShift;
-  }
+
 #define INSTRUCTION_OPERAND_PREDICATE(name, type) \
   bool Is##name() const { return kind() == type; }
-  INSTRUCTION_OPERAND_LIST(INSTRUCTION_OPERAND_PREDICATE)
+  ALLOCATED_OPERAND_LIST(INSTRUCTION_OPERAND_PREDICATE)
+  INSTRUCTION_OPERAND_PREDICATE(Constant, CONSTANT)
+  INSTRUCTION_OPERAND_PREDICATE(Immediate, IMMEDIATE)
   INSTRUCTION_OPERAND_PREDICATE(Unallocated, UNALLOCATED)
   INSTRUCTION_OPERAND_PREDICATE(Invalid, INVALID)
 #undef INSTRUCTION_OPERAND_PREDICATE
+
   bool Equals(const InstructionOperand* other) const {
     return value_ == other->value_;
   }
 
-  void ConvertTo(Kind kind, int index) {
-    DCHECK(kind != UNALLOCATED && kind != INVALID);
-    ConvertTo(kind, index, kInvalidVirtualRegister);
-  }
-
   // Useful for map/set keys.
   bool operator<(const InstructionOperand& op) const {
     return value_ < op.value_;
   }
 
- protected:
   template <typename SubKindOperand>
   static SubKindOperand* New(Zone* zone, const SubKindOperand& op) {
     void* buffer = zone->New(sizeof(op));
     return new (buffer) SubKindOperand(op);
   }
 
-  InstructionOperand(Kind kind, int index, int virtual_register) {
-    ConvertTo(kind, index, virtual_register);
+  static void ReplaceWith(InstructionOperand* dest,
+                          const InstructionOperand* src) {
+    *dest = *src;
   }
 
-  void ConvertTo(Kind kind, int index, int virtual_register) {
+ protected:
+  InstructionOperand(Kind kind, int index, int virtual_register) {
     if (kind == REGISTER || kind == DOUBLE_REGISTER) DCHECK(index >= 0);
-    if (kind != UNALLOCATED) {
+    if (kind != UNALLOCATED && kind != CONSTANT) {
       DCHECK(virtual_register == kInvalidVirtualRegister);
     }
     value_ = KindField::encode(kind);
     value_ |=
         VirtualRegisterField::encode(static_cast<uint32_t>(virtual_register));
     value_ |= static_cast<int64_t>(index) << IndexField::kShift;
-    DCHECK(((kind == UNALLOCATED || kind == INVALID) && index == 0) ||
-           this->index() == index);
   }
 
   typedef BitField64<Kind, 0, 3> KindField;
   typedef BitField64<uint32_t, 3, 32> VirtualRegisterField;
   typedef BitField64<int32_t, 35, 29> IndexField;
 
   uint64_t value_;
 };
 
 struct PrintableInstructionOperand {
@@ skipping 188 matching lines @@
   }
 
   // [lifetime]: Only for non-FIXED_SLOT.
   bool IsUsedAtStart() const {
     DCHECK(basic_policy() == EXTENDED_POLICY);
     return LifetimeField::decode(value_) == USED_AT_START;
   }
 };
 
 
+class ConstantOperand : public InstructionOperand {
+ public:
+  explicit ConstantOperand(int virtual_register)
+      : InstructionOperand(CONSTANT, 0, virtual_register) {}
+
+  int32_t virtual_register() const {
+    return static_cast<int32_t>(VirtualRegisterField::decode(value_));
+  }
+
+  static ConstantOperand* New(Zone* zone, int virtual_register) {
+    return InstructionOperand::New(zone, ConstantOperand(virtual_register));
+  }
+
+  static ConstantOperand* cast(InstructionOperand* op) {
+    DCHECK(op->kind() == CONSTANT);
+    return static_cast<ConstantOperand*>(op);
+  }
+
+  static const ConstantOperand* cast(const InstructionOperand* op) {
+    DCHECK(op->kind() == CONSTANT);
+    return static_cast<const ConstantOperand*>(op);
+  }
+
+  static ConstantOperand cast(const InstructionOperand& op) {
+    DCHECK(op.kind() == CONSTANT);
+    return *static_cast<const ConstantOperand*>(&op);
+  }
+};
+
+
+class ImmediateOperand : public InstructionOperand {
+ public:
+  explicit ImmediateOperand(int index)
+      : InstructionOperand(IMMEDIATE, index, kInvalidVirtualRegister) {}
+
+  int index() const {
+    return static_cast<int64_t>(value_) >> IndexField::kShift;
+  }
+
+  static ImmediateOperand* New(Zone* zone, int index) {
+    return InstructionOperand::New(zone, ImmediateOperand(index));
+  }
+
+  static ImmediateOperand* cast(InstructionOperand* op) {
+    DCHECK(op->kind() == IMMEDIATE);
+    return static_cast<ImmediateOperand*>(op);
+  }
+
+  static const ImmediateOperand* cast(const InstructionOperand* op) {
+    DCHECK(op->kind() == IMMEDIATE);
+    return static_cast<const ImmediateOperand*>(op);
+  }
+
+  static ImmediateOperand cast(const InstructionOperand& op) {
+    DCHECK(op.kind() == IMMEDIATE);
+    return *static_cast<const ImmediateOperand*>(&op);
+  }
+};
+
+
+class AllocatedOperand : public InstructionOperand {
+#define ALLOCATED_OPERAND_CHECK(Name, Kind) || kind == Kind
+#define CHECK_ALLOCATED_KIND()                                   \
+  DCHECK(false ALLOCATED_OPERAND_LIST(ALLOCATED_OPERAND_CHECK)); \
+  USE(kind);
+
+ public:
+  int index() const {
+    return static_cast<int64_t>(value_) >> IndexField::kShift;
+  }
+
+  AllocatedOperand(Kind kind, int index)
+      : InstructionOperand(kind, index, kInvalidVirtualRegister) {
+    CHECK_ALLOCATED_KIND();
+  }
+
+  static AllocatedOperand* New(Zone* zone, Kind kind, int index) {
+    return InstructionOperand::New(zone, AllocatedOperand(kind, index));
+  }
+
+  static AllocatedOperand* cast(InstructionOperand* op) {
+    Kind kind = op->kind();
+    CHECK_ALLOCATED_KIND();
+    return static_cast<AllocatedOperand*>(op);
+  }
+
+  static const AllocatedOperand* cast(const InstructionOperand* op) {
+    Kind kind = op->kind();
+    CHECK_ALLOCATED_KIND();
+    return static_cast<const AllocatedOperand*>(op);
+  }
+
+  static AllocatedOperand cast(const InstructionOperand& op) {
+    Kind kind = op.kind();
+    CHECK_ALLOCATED_KIND();
+    return *static_cast<const AllocatedOperand*>(&op);
+  }
+
+#undef CHECK_ALLOCATED_KIND
+#undef ALLOCATED_OPERAND_CAST_CHECK
+};
+
+
+#define INSTRUCTION_SUBKIND_OPERAND_CLASS(SubKind, kOperandKind)        \
+  class SubKind##Operand FINAL : public AllocatedOperand {              \
+   public:                                                              \
+    explicit SubKind##Operand(int index)                                \
+        : AllocatedOperand(kOperandKind, index) {}                      \
+                                                                        \
+    static SubKind##Operand* New(Zone* zone, int index) {               \
+      return InstructionOperand::New(zone, SubKind##Operand(index));    \
+    }                                                                   \
+                                                                        \
+    static SubKind##Operand* cast(InstructionOperand* op) {             \
+      DCHECK(op->kind() == kOperandKind);                               \
+      return reinterpret_cast<SubKind##Operand*>(op);                   \
+    }                                                                   \
+                                                                        \
+    static const SubKind##Operand* cast(const InstructionOperand* op) { \
+      DCHECK(op->kind() == kOperandKind);                               \
+      return reinterpret_cast<const SubKind##Operand*>(op);             \
+    }                                                                   \
+                                                                        \
+    static SubKind##Operand cast(const InstructionOperand& op) {        \
+      DCHECK(op.kind() == kOperandKind);                                \
+      return *static_cast<const SubKind##Operand*>(&op);                \
+    }                                                                   \
+  };
+ALLOCATED_OPERAND_LIST(INSTRUCTION_SUBKIND_OPERAND_CLASS)
+#undef INSTRUCTION_SUBKIND_OPERAND_CLASS
+
+
 class MoveOperands FINAL {
  public:
   MoveOperands(InstructionOperand* source, InstructionOperand* destination)
       : source_(source), destination_(destination) {}
 
   InstructionOperand* source() const { return source_; }
   void set_source(InstructionOperand* operand) { source_ = operand; }
 
   InstructionOperand* destination() const { return destination_; }
   void set_destination(InstructionOperand* operand) { destination_ = operand; }
 
   // The gap resolver marks moves as "in-progress" by clearing the
   // destination (but not the source).
   bool IsPending() const { return destination_ == NULL && source_ != NULL; }
 
   // True if this move a move into the given destination operand.
   bool Blocks(InstructionOperand* operand) const {
     return !IsEliminated() && source()->Equals(operand);
   }
 
-  // A move is redundant if it's been eliminated, if its source and
-  // destination are the same, or if its destination is  constant.
+  // A move is redundant if it's been eliminated or if its source and
+  // destination are the same.
   bool IsRedundant() const {
-    return IsEliminated() || source_->Equals(destination_) ||
-           (destination_ != NULL && destination_->IsConstant());
+    DCHECK_IMPLIES(destination_ != nullptr, !destination_->IsConstant());
+    return IsEliminated() || source_->Equals(destination_);
   }
 
   // We clear both operands to indicate move that's been eliminated.
   void Eliminate() { source_ = destination_ = NULL; }
   bool IsEliminated() const {
     DCHECK(source_ != NULL || destination_ == NULL);
     return source_ == NULL;
   }
 
  private:
   InstructionOperand* source_;
   InstructionOperand* destination_;
 };
 
 
 struct PrintableMoveOperands {
   const RegisterConfiguration* register_configuration_;
   const MoveOperands* move_operands_;
 };
 
 
 std::ostream& operator<<(std::ostream& os, const PrintableMoveOperands& mo);
 
 
-#define INSTRUCTION_SUBKIND_OPERAND_CLASS(SubKind, kOperandKind)        \
-  class SubKind##Operand FINAL : public InstructionOperand {            \
-   public:                                                              \
-    explicit SubKind##Operand(int index)                                \
-        : InstructionOperand(kOperandKind, index) {}                    \
-                                                                        \
-    static SubKind##Operand* New(int index, Zone* zone) {               \
-      return InstructionOperand::New(zone, SubKind##Operand(index));    \
-    }                                                                   \
-                                                                        \
-    static SubKind##Operand* cast(InstructionOperand* op) {             \
-      DCHECK(op->kind() == kOperandKind);                               \
-      return reinterpret_cast<SubKind##Operand*>(op);                   \
-    }                                                                   \
-                                                                        \
-    static const SubKind##Operand* cast(const InstructionOperand* op) { \
-      DCHECK(op->kind() == kOperandKind);                               \
-      return reinterpret_cast<const SubKind##Operand*>(op);             \
-    }                                                                   \
-                                                                        \
-    static SubKind##Operand cast(const InstructionOperand& op) {        \
-      DCHECK(op.kind() == kOperandKind);                                \
-      return *static_cast<const SubKind##Operand*>(&op);                \
-    }                                                                   \
-  };
-INSTRUCTION_OPERAND_LIST(INSTRUCTION_SUBKIND_OPERAND_CLASS)
-#undef INSTRUCTION_SUBKIND_OPERAND_CLASS
-
-
 class ParallelMove FINAL : public ZoneObject {
  public:
   explicit ParallelMove(Zone* zone) : move_operands_(4, zone) {}
 
   void AddMove(InstructionOperand* from, InstructionOperand* to, Zone* zone) {
     move_operands_.Add(MoveOperands(from, to), zone);
   }
 
   bool IsRedundant() const;
 
@@ skipping 601 matching lines @@
 
    private:
     explicit StateId(int id) : id_(id) {}
     int id_;
   };
 
   StateId AddFrameStateDescriptor(FrameStateDescriptor* descriptor);
   FrameStateDescriptor* GetFrameStateDescriptor(StateId deoptimization_id);
   int GetFrameStateDescriptorCount();
 
-  RpoNumber InputRpo(Instruction* instr, size_t index) {
-    InstructionOperand* operand = instr->InputAt(index);
-    Constant constant = operand->IsImmediate() ? GetImmediate(operand->index())
-                                               : GetConstant(operand->index());
-    return constant.ToRpoNumber();
-  }
+  RpoNumber InputRpo(Instruction* instr, size_t index);
 
  private:
   friend std::ostream& operator<<(std::ostream& os,
                                   const PrintableInstructionSequence& code);
 
   typedef std::set<int, std::less<int>, ZoneIntAllocator> VirtualRegisterSet;
 
   Isolate* isolate_;
   Zone* const zone_;
   InstructionBlocks* const instruction_blocks_;
@@ skipping 18 matching lines @@
 
 
 std::ostream& operator<<(std::ostream& os,
                          const PrintableInstructionSequence& code);
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_COMPILER_INSTRUCTION_H_