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 IceOperand class and its target-independent
+// subclasses.  The main classes are IceVariable, which represents an
+// LLVM variable that is either register- or stack-allocated, and the
+// IceConstant hierarchy, which represents integer, floating-point,
+// and/or symbolic constants.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef SUBZERO_ICEOPERAND_H
+#define SUBZERO_ICEOPERAND_H
+
+#include "IceDefs.h"
+#include "IceTypes.h"
+
+class IceOperand {
+public:
+  enum OperandKind {
+    Constant,
+    ConstantInteger,
+    ConstantFloat,
+    ConstantDouble,
+    ConstantRelocatable,
+    Constant_Num,
+    Variable,
+    // Target-specific operand classes use Target as the starting
+    // point for their Kind enum space.
+    Target
+  };
+  OperandKind getKind() const { return Kind; }
+  IceType getType() const { return Type; }
+
+  // Every IceOperand keeps an array of the IceVariables 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.
+  uint32_t getNumVars() const { return NumVars; }
+  IceVariable *getVar(uint32_t I) const {
+    assert(I < getNumVars());
+    return Vars[I];
+  }
+  virtual void setUse(const IceInst *Inst, const IceCfgNode *Node) {}
+  virtual void dump(IceOstream &Str) const;
+
+  virtual ~IceOperand() {}
+
+protected:
+  IceOperand(IceCfg *Cfg, OperandKind Kind, IceType Type)
+      : Type(Type), Kind(Kind) {}
+  const IceType Type;
+  const OperandKind Kind;
+  // Vars and NumVars are initialized by the derived class.
+  uint32_t NumVars;
+  IceVariable **Vars;
+};
+
+IceOstream &operator<<(IceOstream &Str, const IceOperand *O);
+
+// IceConstant is the abstract base class for constants.
+// TODO: better design of a minimal per-module constant pool,
+// including synchronized access for parallel translation.
+class IceConstant : public IceOperand {
+public:
+  virtual void dump(IceOstream &Str) const = 0;
+
+  static bool classof(const IceOperand *Operand) {
+    OperandKind Kind = Operand->getKind();
+    return Kind >= Constant && Kind <= Constant_Num;
+  }
+
+protected:
+  IceConstant(IceCfg *Cfg, OperandKind Kind, IceType Type)
+      : IceOperand(Cfg, Kind, Type) {
+    Vars = NULL;
+    NumVars = 0;
+  }
+};
+
+// IceConstantPrimitive<> wraps a primitive type.
+template <typename T, IceOperand::OperandKind K>
+class IceConstantPrimitive : public IceConstant {
+public:
+  static IceConstantPrimitive *create(IceCfg *Cfg, IceType Type, T Value) {
+    return new IceConstantPrimitive(Cfg, Type, Value);
+  }
+  T getValue() const { return Value; }
+  virtual void dump(IceOstream &Str) const { Str << getValue(); }
+
+  static bool classof(const IceOperand *Operand) {
+    return Operand->getKind() == K;
+  }
+
+private:
+  IceConstantPrimitive(IceCfg *Cfg, IceType Type, T Value)
+      : IceConstant(Cfg, K, Type), Value(Value) {}
+  const T Value;
+};
+
+typedef IceConstantPrimitive<uint64_t, IceOperand::ConstantInteger>
+IceConstantInteger;
+typedef IceConstantPrimitive<float, IceOperand::ConstantFloat> IceConstantFloat;
+typedef IceConstantPrimitive<double, IceOperand::ConstantDouble>
+IceConstantDouble;
+
+// IceConstantRelocatable represents a symbolic constant combined with
+// a fixed offset.
+class IceConstantRelocatable : public IceConstant {
+public:
+  static IceConstantRelocatable *create(IceCfg *Cfg, uint32_t CPIndex,
+                                        IceType Type, const void *Handle,
+                                        int64_t Offset,
+                                        const IceString &Name = "") {
+    return new IceConstantRelocatable(Cfg, Type, Handle, Offset, Name, CPIndex);
+  }
+  uint32_t getCPIndex() const { return CPIndex; }
+  const void *getHandle() const { return Handle; }
+  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(IceOstream &Str) const;
+
+  static bool classof(const IceOperand *Operand) {
+    OperandKind Kind = Operand->getKind();
+    return Kind == ConstantRelocatable;
+  }
+
+private:
+  IceConstantRelocatable(IceCfg *Cfg, IceType Type, const void *Handle,
+                         int64_t Offset, const IceString &Name,
+                         uint32_t CPIndex)
+      : IceConstant(Cfg, ConstantRelocatable, Type), CPIndex(CPIndex),
+        Handle(Handle), Offset(Offset), Name(Name), SuppressMangling(false) {}
+  const uint32_t CPIndex;   // index into ICE constant pool
+  const void *const Handle; // opaque handle e.g. to LLVM
+  const int64_t Offset;     // fixed offset to add
+  const IceString Name;     // optional for debug/dump
+  bool SuppressMangling;
+};
+
+// IceVariable 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 IceVariable : public IceOperand {
+public:
+  static IceVariable *create(IceCfg *Cfg, IceType Type, const IceCfgNode *Node,
+                             uint32_t Index, const IceString &Name) {
+    return new IceVariable(Cfg, Type, Node, Index, Name);
+  }
+
+  uint32_t getIndex() const { return Number; }
+  IceString getName() const;
+
+  IceInst *getDefinition() const { return DefInst; }
+  void setDefinition(IceInst *Inst, const IceCfgNode *Node);
+  void replaceDefinition(IceInst *Inst, const IceCfgNode *Node);
+
+  const IceCfgNode *getLocalUseNode() const { return DefNode; }
+  bool isMultiblockLife() const { return (DefNode == NULL); }
+  void setUse(const IceInst *Inst, const IceCfgNode *Node);
+
+  bool getIsArg() const { return IsArgument; }
+  void setIsArg(IceCfg *Cfg);
+
+  virtual void dump(IceOstream &Str) const;
+
+  static bool classof(const IceOperand *Operand) {
+    return Operand->getKind() == Variable;
+  }
+
+private:
+  IceVariable(IceCfg *Cfg, IceType Type, const IceCfgNode *Node, uint32_t Index,
+              const IceString &Name)
+      : IceOperand(Cfg, Variable, Type), Number(Index), Name(Name),
+        DefInst(NULL), DefNode(Node), IsArgument(false) {
+    Vars = new IceVariable *[1];

[jvoung (off chromium), 2014/03/22 00:29:39]

what deletes the Vars?

The IceOperand dtor doesn't and it doesn't look like this uses a scoped array
ptr?

[Jim Stichnoth, 2014/03/24 13:18:53]

Done, good catch.

Most allocation in Subzero is supposed to be done using the BumpPtrAllocator in
IceCfg::Allocator.  This is currently done for instructions, but needs to be
done for operands as well.  I still need to deal with places where STL-style
containers are used, but I hope to defer that for a few more CLs.

+    Vars[0] = this;
+    NumVars = 1;
+  }
+  // Number is unique across all variables, and is used as a
+  // (bit)vector index for liveness analysis.
+  const uint32_t Number;
+  // Name is optional.
+  const IceString Name;
+  // DefInst is the instruction that produces this variable as its
+  // dest.
+  IceInst *DefInst;
+  // DefOrUseNode is the node where this variable was produced, and is

[jvoung (off chromium), 2014/03/22 00:29:39]

comment says DefOrUseNode but field name is DefNode

[Jim Stichnoth, 2014/03/24 13:18:53]

Done.  (And fixed the same problem in IceDefs.h.)

+  // reset to NULL if it is used outside that node.  This is used for
+  // detecting isMultiblockLife().
+  const IceCfgNode *DefNode;
+  bool IsArgument;
+};
+
+#endif // SUBZERO_ICEOPERAND_H