Initial skeleton of Subzero.

src/IceOperand.h

+//===- subzero/src/IceOperand.h - High-level operands -----------*- C++ -*-===//
+//
+//                        The Subzero Code Generator
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file declares the Operand class and its target-independent
+// subclasses.  The main classes are Variable, which represents an
+// LLVM variable that is either register- or stack-allocated, and the
+// Constant hierarchy, which represents integer, floating-point,
+// and/or symbolic constants.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef SUBZERO_SRC_ICEOPERAND_H
+#define SUBZERO_SRC_ICEOPERAND_H
+
+#include "IceDefs.h"
+#include "IceTypes.h"
+
+namespace Ice {
+
+class Operand {
+public:
+  enum OperandKind {
+    kConst_Base,
+    kConstInteger,
+    kConstFloat,
+    kConstDouble,
+    kConstRelocatable,
+    kConst_Num,
+    kVariable,
+    // Target-specific operand classes use kTarget as the starting
+    // point for their Kind enum space.
+    kTarget
+  };
+  OperandKind getKind() const { return Kind; }
+  Type getType() const { return Ty; }
+
+  // Every Operand keeps an array of the Variables referenced in
+  // the operand.  This is so that the liveness operations can get
+  // quick access to the variables of interest, without having to dig
+  // so far into the operand.
+  SizeT getNumVars() const { return NumVars; }
+  Variable *getVar(SizeT I) const {
+    assert(I < getNumVars());
+    return Vars[I];
+  }
+  virtual void dump(const Cfg *Func) const = 0;
+
+  // Query whether this object was allocated in isolation, or added to
+  // some higher-level pool.  This determines whether a containing
+  // object's destructor should delete this object.  Generally,
+  // constants are pooled globally, variables are pooled per-CFG, and
+  // target-specific operands are not pooled.
+  virtual bool isPooled() const { return false; }
+
+  virtual ~Operand() {}
+
+protected:
+  Operand(OperandKind Kind, Type Ty)
+      : Ty(Ty), Kind(Kind), NumVars(0), Vars(NULL) {}
+
+  const Type Ty;
+  const OperandKind Kind;
+  // Vars and NumVars are initialized by the derived class.
+  SizeT NumVars;
+  Variable **Vars;
+
+private:
+  Operand(const Operand &) LLVM_DELETED_FUNCTION;
+  Operand &operator=(const Operand &) LLVM_DELETED_FUNCTION;
+};
+
+// Constant is the abstract base class for constants.  All
+// constants are allocated from a global arena and are pooled.
+class Constant : public Operand {
+public:
+  virtual void dump(const Cfg *Func) const = 0;
+
+  static bool classof(const Operand *Operand) {
+    OperandKind Kind = Operand->getKind();
+    return Kind >= kConst_Base && Kind <= kConst_Num;
+  }
+
+protected:
+  Constant(OperandKind Kind, Type Ty) : Operand(Kind, Ty) {
+    Vars = NULL;
+    NumVars = 0;
+  }
+  virtual ~Constant() {}
+
+private:
+  Constant(const Constant &) LLVM_DELETED_FUNCTION;
+  Constant &operator=(const Constant &) LLVM_DELETED_FUNCTION;
+};
+
+// ConstantPrimitive<> wraps a primitive type.
+template <typename T, Operand::OperandKind K>
+class ConstantPrimitive : public Constant {
+public:
+  static ConstantPrimitive *create(GlobalContext *Ctx, Type Ty, T Value) {
+    return new (Ctx->allocate<ConstantPrimitive>())
+        ConstantPrimitive(Ty, Value);
+  }
+  T getValue() const { return Value; }
+  virtual void dump(const Cfg *Func) const {
+    Ostream &Str = Func->getContext()->getStrDump();
+    Str << getValue();
+  }
+
+  static bool classof(const Operand *Operand) {
+    return Operand->getKind() == K;
+  }
+
+private:
+  ConstantPrimitive(Type Ty, T Value) : Constant(K, Ty), Value(Value) {}
+  ConstantPrimitive(const ConstantPrimitive &) LLVM_DELETED_FUNCTION;
+  ConstantPrimitive &operator=(const ConstantPrimitive &) LLVM_DELETED_FUNCTION;
+  virtual ~ConstantPrimitive() {}
+  const T Value;
+};
+
+typedef ConstantPrimitive<uint64_t, Operand::kConstInteger> ConstantInteger;
+typedef ConstantPrimitive<float, Operand::kConstFloat> ConstantFloat;
+typedef ConstantPrimitive<double, Operand::kConstDouble> ConstantDouble;
+
+// RelocatableTuple bundles the parameters that are used to
+// construct an ConstantRelocatable.  It is done this way so that
+// ConstantRelocatable can fit into the global constant pool
+// template mechanism.
+class RelocatableTuple {
+  RelocatableTuple &operator=(const RelocatableTuple &) LLVM_DELETED_FUNCTION;
+
+public:
+  RelocatableTuple(const int64_t Offset, const IceString &Name,
+                   bool SuppressMangling)
+      : Offset(Offset), Name(Name), SuppressMangling(SuppressMangling) {}
+  RelocatableTuple(const RelocatableTuple &Other)
+      : Offset(Other.Offset), Name(Other.Name),
+        SuppressMangling(Other.SuppressMangling) {}
+
+  const int64_t Offset;
+  const IceString Name;
+  bool SuppressMangling;
+};
+
+bool operator<(const RelocatableTuple &A, const RelocatableTuple &B);
+
+// ConstantRelocatable represents a symbolic constant combined with
+// a fixed offset.
+class ConstantRelocatable : public Constant {
+public:
+  static ConstantRelocatable *create(GlobalContext *Ctx, Type Ty,
+                                     const RelocatableTuple &Tuple) {
+    return new (Ctx->allocate<ConstantRelocatable>()) ConstantRelocatable(
+        Ty, Tuple.Offset, Tuple.Name, Tuple.SuppressMangling);
+  }
+  int64_t getOffset() const { return Offset; }
+  IceString getName() const { return Name; }
+  void setSuppressMangling(bool Value) { SuppressMangling = Value; }
+  bool getSuppressMangling() const { return SuppressMangling; }
+  virtual void dump(const Cfg *Func) const;
+
+  static bool classof(const Operand *Operand) {
+    OperandKind Kind = Operand->getKind();
+    return Kind == kConstRelocatable;
+  }
+
+private:
+  ConstantRelocatable(Type Ty, int64_t Offset, const IceString &Name,
+                      bool SuppressMangling)
+      : Constant(kConstRelocatable, Ty), Offset(Offset), Name(Name),
+        SuppressMangling(SuppressMangling) {}
+  ConstantRelocatable(const ConstantRelocatable &) LLVM_DELETED_FUNCTION;
+  ConstantRelocatable &
+  operator=(const ConstantRelocatable &) LLVM_DELETED_FUNCTION;
+  virtual ~ConstantRelocatable() {}
+  const int64_t Offset; // fixed offset to add
+  const IceString Name; // optional for debug/dump
+  bool SuppressMangling;
+};
+
+// Variable represents an operand that is register-allocated or
+// stack-allocated.  If it is register-allocated, it will ultimately
+// have a non-negative RegNum field.
+class Variable : public Operand {
+public:
+  static Variable *create(Cfg *Func, Type Ty, const CfgNode *Node, SizeT Index,
+                          const IceString &Name) {
+    return new (Func->allocate<Variable>()) Variable(Ty, Node, Index, Name);
+  }
+
+  SizeT getIndex() const { return Number; }
+  IceString getName() const;
+
+  Inst *getDefinition() const { return DefInst; }
+  void setDefinition(Inst *Inst, const CfgNode *Node);
+  void replaceDefinition(Inst *Inst, const CfgNode *Node);
+
+  const CfgNode *getLocalUseNode() const { return DefNode; }
+  bool isMultiblockLife() const { return (DefNode == NULL); }
+  void setUse(const Inst *Inst, const CfgNode *Node);
+
+  bool getIsArg() const { return IsArgument; }
+  void setIsArg(Cfg *Func);
+
+  virtual void dump(const Cfg *Func) const;
+
+  static bool classof(const Operand *Operand) {
+    return Operand->getKind() == kVariable;
+  }
+
+private:
+  Variable(Type Ty, const CfgNode *Node, SizeT Index, const IceString &Name)
+      : Operand(kVariable, Ty), Number(Index), Name(Name), DefInst(NULL),
+        DefNode(Node), IsArgument(false) {
+    Vars = VarsReal;
+    Vars[0] = this;
+    NumVars = 1;
+  }
+  Variable(const Variable &) LLVM_DELETED_FUNCTION;
+  Variable &operator=(const Variable &) LLVM_DELETED_FUNCTION;
+  virtual ~Variable() {}
+  // Number is unique across all variables, and is used as a
+  // (bit)vector index for liveness analysis.
+  const SizeT Number;
+  // Name is optional.
+  const IceString Name;
+  // DefInst is the instruction that produces this variable as its
+  // dest.
+  Inst *DefInst;
+  // DefNode is the node where this variable was produced, and is
+  // reset to NULL if it is used outside that node.  This is used for
+  // detecting isMultiblockLife().  TODO: Collapse this to a single
+  // bit and use a separate pass to calculate the values across the
+  // Cfg.  This saves space in the Variable, and removes the fragility
+  // of incrementally computing and maintaining the information.
+  const CfgNode *DefNode;
+  bool IsArgument;
+  // VarsReal (and Operand::Vars) are set up such that Vars[0] ==
+  // this.
+  Variable *VarsReal[1];
+};
+
+} // end of namespace Ice
+
+#endif // SUBZERO_SRC_ICEOPERAND_H