/*****************************************************************************
 Copyright (C) 2009-2010 University of Utah
 All Rights Reserved.

 Purpose:
   CHiLL's compiler intermediate representation interface that extends
 Omega's builder interface to accomodate compiler analyses and
 extra code generation.
.
 Notes:
   Unlike CG_outputRepr, IR_Symbol, IR_Ref and IR_Control are place holders
 to the underlying code, thus deleting or duplicating them does not affect
 the actual code.  Similar to Omega builder's memory allocation strategy,
 all non-const pointer parameters of CG_outputRepr/IR_Symbol/IR_Ref/IR_Control
 are destroyed after the call.

 History:
   02/2009 Created by Chun Chen.
   06/2010 Add IR_Control interface, by chun.  
*****************************************************************************/

#ifndef IR_CODE_HH
#define IR_CODE_HH

#include <ir_enums.hh>
#include <chillAST/chillASTs.hh>
#include <vector>
#include <code_gen/CG_outputRepr.h>
#include <code_gen/CG_outputBuilder.h>

/*!
 * \file
 * \brief CHiLL's compiler intermediate representation interface that extends Omega's builder interface to accomodate compiler analyses and extra code generation.
 *
 * Unlike CG_outputRepr, IR_Symbol,IR_Ref and IR_Control are place holders
 * to the underlying code, thus deleting or duplicating them does not affect
 * the actual code.  Similar to Omega builder's memory allocation strategy,
 * all non-const pointer parameters of CG_outputRepr/IR_Symbol/IR_Ref/IR_Control
 * are destroyed after the call.
 */

class IR_Code; // forward declaration

/*!
 * @brief Base abstract class for scalar and array symbols.
 *
 * This is a place holder for related declaration in IR code.
 */
struct IR_Symbol {
  const IR_Code *ir_;

  //! ir_ is not the responsibility of this object
  virtual ~IR_Symbol() { }

  virtual int n_dim() const = 0;
  virtual std::string name() const = 0;

  virtual bool operator==(const IR_Symbol &that) const = 0;

  virtual bool operator!=(const IR_Symbol &that) const { return !(*this == that); }

  //! shallow copy
  virtual IR_Symbol *clone() const = 0;

  virtual bool isScalar() const { return false; }
  virtual bool isArray() const { return false; }
  virtual bool isPointer() const { return false; }

  //IR_SYMBOL_TYPE symtype; // base type: int, float, double, struct, .... typedef'd something
  //IR_SYMBOL_TYPE getDatatype() ; 
};


struct IR_ScalarSymbol : public IR_Symbol {
  virtual ~IR_ScalarSymbol() {}

  int n_dim() const { return 0; } // IR_ScalarSymbol
  virtual int size() const = 0;

  bool isScalar() const { return true; }
};


struct IR_ArraySymbol : public IR_Symbol {
  virtual ~IR_ArraySymbol() {}

  virtual int elem_size() const = 0;

  virtual omega::CG_outputRepr *size(int dim) const = 0;

  virtual IR_ARRAY_LAYOUT_TYPE layout_type() const = 0;

  virtual IR_CONSTANT_TYPE elem_type() const = 0;

  bool isArray() const { return true; }
};

struct IR_PointerSymbol : public IR_Symbol {
  virtual ~IR_PointerSymbol() {}

  virtual omega::CG_outputRepr *size(int dim) const = 0;

  virtual void set_size(int dim, omega::CG_outputRepr *) = 0;

  virtual IR_CONSTANT_TYPE elem_type() const = 0;

  bool isPointer() const { return true; }
};


/*!
 * @brief Base abstract class for scalar and array references.
 *
 * This is a place holder for related code in IR code.
 */
struct IR_Ref {
  const IR_Code *ir_;
  //! ir_ is not the responsibility of this object
  virtual ~IR_Ref() { }

  virtual int n_dim() const = 0;
  virtual bool is_write() const = 0;

  virtual std::string name() const = 0;

  virtual bool operator==(const IR_Ref &that) const = 0;

  virtual bool operator!=(const IR_Ref &that) const { return !(*this == that); }

  virtual omega::CG_outputRepr *convert() = 0;

  //! shallow copy
  virtual IR_Ref *clone() const = 0;
  virtual void Dump() const {
    fprintf(stderr, "some IR_*Ref needs to implement Dump()\n");
    int *i = 0;
    int j = i[0];
  };
};


struct IR_ConstantRef : public IR_Ref {
  IR_CONSTANT_TYPE type_;

  virtual ~IR_ConstantRef() {}

  int n_dim() const { return 0; } // IR_ConstantRef
  bool is_write() const { return false; }

  std::string name() const { return std::string(); }

  virtual bool is_integer() const { return type_ == IR_CONSTANT_INT; }

  virtual omega::coef_t integer() const = 0;
};


struct IR_ScalarRef : public IR_Ref {
  virtual ~IR_ScalarRef() {}

  int n_dim() const { return 0; } // IR_ScalarRef
  virtual IR_ScalarSymbol *symbol() const = 0;

  std::string name() const {
    IR_ScalarSymbol *sym = symbol(); // really inefficient. MAKE a symbol, just to get a name
    std::string s = sym->name();
    delete sym;
    return s;
  }

  virtual int size() const {
    IR_ScalarSymbol *sym = symbol();
    int s = sym->size();
    delete sym;
    return s;
  }
};


struct IR_ArrayRef : public IR_Ref {
  virtual ~IR_ArrayRef() {}

  int n_dim() const {  // IR_ArrayRef  returns the size of the array
    IR_ArraySymbol *sym = symbol();
    int n = sym->n_dim();
    // ?? delete sym;
    return n;
  }

  virtual omega::CG_outputRepr *index(int dim) const = 0;

  virtual IR_ArraySymbol *symbol() const = 0;

  virtual std::string name() const {
    // makes (constructs!) a symbol, just to copy a string!
    IR_ArraySymbol *sym = symbol(); // TODO exceedingly wasteful 
    std::string s = sym->name();
    // ?? delete sym; (goes out of scope, so deletes itself)
    return s; // s ALSO goes out of scope but perhaps the info is copied at the other end
  }

  virtual int elem_size() const {
    IR_ArraySymbol *sym = symbol();
    int s = sym->elem_size();
    // ?? delete sym;
    return s;
  }

  virtual IR_ARRAY_LAYOUT_TYPE layout_type() const {
    IR_ArraySymbol *sym = symbol();
    IR_ARRAY_LAYOUT_TYPE t = sym->layout_type();
    // ?? delete sym;
    return t;
  }

  virtual void Dump() const { fprintf(stderr, "IR_ArrayRef needs to implement Dump()\n"); };
};

struct IR_PointerArrayRef : public IR_Ref {

  const IR_Code *ir_;

  virtual ~IR_PointerArrayRef() {}

  int n_dim() const {  // IR_PointerArrayRef returns size of the ... symbol?
    IR_PointerSymbol *sym = symbol();
    int n = sym->n_dim();
    //Anand: Hack, fix later
    //delete sym;
    return n;
  }

  virtual omega::CG_outputRepr *index(int dim) const = 0;

  virtual IR_PointerSymbol *symbol() const = 0;

  std::string name() const {
    IR_PointerSymbol *sym = symbol();
    std::string s = sym->name();
//Anand: Hack, fix later
    //delete sym;
    return s;
  }


};


struct IR_Block;

//! Base abstract class for code structures.
/*!
 * This is a place holder for the actual structure in the IR code.
 * However, in cases that original source code may be transformed during
 * loop initialization such as converting a while loop to a for loop or
 * reconstructing the loop from low level IR code, the helper loop class (NOT
 * IMPLEMENTED) must contain the transformed code that needs to be
 * freed when out of service.
 */
struct IR_Control {
  const IR_Code *ir_;

  virtual ~IR_Control() {/* ir_ is not the responsibility of this object */}

  virtual IR_CONTROL_TYPE type() const = 0;

  virtual IR_Block *convert() = 0;

  virtual IR_Control *clone() const = 0;  /* shallow copy */
};


struct IR_Loop : public IR_Control {
  virtual ~IR_Loop() {}

  virtual IR_ScalarSymbol *index() const = 0;

  virtual omega::CG_outputRepr *lower_bound() const = 0;

  virtual omega::CG_outputRepr *upper_bound() const = 0;

  virtual IR_CONDITION_TYPE stop_cond() const = 0;

  virtual IR_Block *body() const = 0;

  virtual int step_size() const = 0;

  IR_CONTROL_TYPE type() const { return IR_CONTROL_LOOP; }
};


struct IR_Block : public IR_Control {
  virtual ~IR_Block() {}

  virtual omega::CG_outputRepr *extract() const = 0;

  IR_Block *convert() { return this; }

  IR_CONTROL_TYPE type() const { return IR_CONTROL_BLOCK; }

  virtual omega::CG_outputRepr *original() const = 0;
};


struct IR_If : public IR_Control {
  virtual ~IR_If() {}

  virtual omega::CG_outputRepr *condition() const = 0;

  virtual IR_Block *then_body() const = 0;

  virtual IR_Block *else_body() const = 0;

  IR_CONTROL_TYPE type() const { return IR_CONTROL_IF; }
};


struct IR_While : public IR_Control {
  // NOT IMPLEMENTED
};


// TODO made a lot of definition to pass instantiation for IR_clangCode
//! Abstract class for compiler IR.
class IR_Code {
protected:
  omega::CG_outputBuilder *ocg_;
  omega::CG_outputRepr *init_code_;
  omega::CG_outputRepr *cleanup_code_;

  static int ir_pointer_counter;
  static int ir_array_counter;

public:

  int getPointerCounter() { return ir_pointer_counter; }

  int getArrayCounter() { return ir_array_counter; }

  // TODO can't get the initialize of counters to work !! 
  int getAndIncrementPointerCounter() {
    if (ir_pointer_counter == 0) ir_pointer_counter = 1;
    ir_pointer_counter++;
    return ir_pointer_counter - 1;
  }

  int getAndIncrementArrayCounter() {
    if (ir_array_counter == 0) ir_array_counter = 1;
    ir_array_counter += 1;
    return ir_array_counter - 1;
  }

  chillAST_FunctionDecl *func_defn;     //!< the function we're modifying
  chillAST_FunctionDecl *GetChillFuncDefinition() { return func_defn; };

  IR_Code() {
    ocg_ = NULL;
    init_code_ = cleanup_code_ = NULL;
  }

  virtual ~IR_Code() {
    delete ocg_;
    delete init_code_;
    delete cleanup_code_;
  } /* the content of init and cleanup code have already been released in derived classes */

  omega::CG_outputRepr *init_code() { return init_code_; }

  /*!
   * \param memory_type is for differentiating the location of
   *    where the new memory is allocated. this is useful for
   *    processors with heterogeneous memory hierarchy.
   */
  virtual IR_ScalarSymbol *CreateScalarSymbol(const IR_Symbol *sym, int memory_type) = 0;

  virtual IR_ScalarSymbol *CreateScalarSymbol(IR_CONSTANT_TYPE type, int memory_type, std::string name = "") {
    CHILL_ERROR("NOT IMPLEMENTED\n");
    return NULL;
  }

  virtual IR_ArraySymbol *CreateArraySymbol(const IR_Symbol *sym,
                                            std::vector<omega::CG_outputRepr *> &size,
                                            int memory_type) = 0;

  virtual IR_ArraySymbol *CreateArraySymbol(omega::CG_outputRepr *type,
                                            std::vector<omega::CG_outputRepr *> &size_repr) {
    CHILL_ERROR("NOT IMPLEMENTED\n");
    return NULL;
  }

  virtual IR_PointerSymbol *CreatePointerSymbol(const IR_Symbol *sym,
                                                std::vector<omega::CG_outputRepr *> &size_repr) {
    CHILL_ERROR("NOT IMPLEMENTED\n");
    return NULL;
  }

  virtual IR_PointerSymbol *CreatePointerSymbol(const IR_CONSTANT_TYPE type,
                                                std::vector<omega::CG_outputRepr *> &size_repr,
                                                std::string name = "") {
    CHILL_ERROR("NOT IMPLEMENTED\n");
    return NULL;
  }

  virtual IR_PointerSymbol *CreatePointerSymbol(omega::CG_outputRepr *type,
                                                std::vector<omega::CG_outputRepr *> &size_repr) {
    CHILL_ERROR("NOT IMPLEMENTED\n");
    return NULL;
  }

  virtual IR_ScalarRef *CreateScalarRef(const IR_ScalarSymbol *sym) = 0;

  virtual IR_ArrayRef *CreateArrayRef(const IR_ArraySymbol *sym, std::vector<omega::CG_outputRepr *> &index) = 0;

  virtual omega::CG_outputRepr *CreateArrayRefRepr(const IR_ArraySymbol *sym,
                                                   std::vector<omega::CG_outputRepr *> &index) {
    CHILL_ERROR("NOT IMPLEMENTED\n");
    return NULL;
  }

  virtual IR_PointerArrayRef *CreatePointerArrayRef(IR_PointerSymbol *sym,
                                                    std::vector<omega::CG_outputRepr *> &index) {
    CHILL_ERROR("NOT IMPLEMENTED\n");
    return NULL;
  }

  virtual int ArrayIndexStartAt() { return 0; }

  virtual void CreateDefineMacro(std::string s, std::string args, omega::CG_outputRepr *repr) {
    CHILL_ERROR("NOT IMPLEMENTED\n");
  }

  virtual void CreateDefineMacro(std::string s, std::string args, std::string repr) {
    CHILL_ERROR("NOT IMPLEMENTED\n");
  }

  virtual void CreateDefineMacro(std::string s, std::vector<std::string> args,
                                 omega::CG_outputRepr *repr) {};  // TODO make pure virtual

  virtual omega::CG_outputRepr *CreateArrayType(IR_CONSTANT_TYPE type, omega::CG_outputRepr *size) {
    CHILL_ERROR("NOT IMPLEMENTED\n");
    return NULL;
  }

  virtual omega::CG_outputRepr *CreatePointerType(IR_CONSTANT_TYPE type) {
    CHILL_ERROR("NOT IMPLEMENTED\n");
    return NULL;
  }

  virtual omega::CG_outputRepr *CreatePointerType(omega::CG_outputRepr *type) {
    CHILL_ERROR("NOT IMPLEMENTED\n");
    return NULL;
  }

  virtual omega::CG_outputRepr *CreateScalarType(IR_CONSTANT_TYPE type) {
    CHILL_ERROR("NOT IMPLEMENTED\n");
    return NULL;
  }
  /*!
  * Array references should be returned in their accessing order.
  *
  * ~~~
  * e.g. s1: A[i] = A[i-1]
  *      s2: B[C[i]] = D[i] + E[i]
  * return A[i-1], A[i], D[i], E[i], C[i], B[C[i]] in this order.
  * ~~~
  */
  virtual std::vector<IR_ArrayRef *> FindArrayRef(const omega::CG_outputRepr *repr) const = 0;

  virtual std::vector<IR_PointerArrayRef *> FindPointerArrayRef(const omega::CG_outputRepr *repr) const {
    fprintf(stderr, "ir_code.hh  SOME SUBCLASS OF ir_code did not implement CreateArrayRefRepr()\n");
    CHILL_ERROR("NOT IMPLEMENTED\n");
    return std::vector<IR_PointerArrayRef *>();
  }

  virtual std::vector<IR_ScalarRef *> FindScalarRef(const omega::CG_outputRepr *repr) const = 0;

  virtual bool parent_is_array(IR_ArrayRef *a) {
    fprintf(stderr, "ir_code.hh  SOME SUBCLASS OF ir_code did not implement CreateArrayRefRepr()\n");
    CHILL_ERROR("NOT IMPLEMENTED\n");
    return false;
  }
  /*!
   * If there is no sub structure interesting inside the block, return empty,
   * so we know when to stop looking inside.
   */
  virtual std::vector<IR_Control *> FindOneLevelControlStructure(const IR_Block *block) const = 0;
  /*!
   * All controls must be in the same block, at the same level and in
   * contiguous lexical order as appeared in parameter vector.
   */
  virtual IR_Block *MergeNeighboringControlStructures(const std::vector<IR_Control *> &controls) const = 0;

  virtual IR_Block *GetCode() const = 0;

  virtual IR_Control *GetCode(omega::CG_outputRepr *code) const {
    CHILL_ERROR("NOT IMPLEMENTED\n");
    return NULL;
  }

  virtual void ReplaceCode(IR_Control *old, omega::CG_outputRepr *repr) = 0;

  virtual void ReplaceExpression(IR_Ref *old, omega::CG_outputRepr *repr) = 0;

  virtual IR_OPERATION_TYPE QueryExpOperation(const omega::CG_outputRepr *repr) const = 0;

  virtual IR_CONDITION_TYPE QueryBooleanExpOperation(const omega::CG_outputRepr *repr) const = 0;

  virtual std::vector<omega::CG_outputRepr *> QueryExpOperand(const omega::CG_outputRepr *repr) const = 0;

  virtual IR_Ref *Repr2Ref(const omega::CG_outputRepr *repr) const = 0;

  // Manu:: Added functions required for reduction operation
  virtual bool FromSameStmt(IR_ArrayRef *A, IR_ArrayRef *B) {
    CHILL_ERROR("NOT IMPLEMENTED\n");
    return NULL;
  }

  virtual void printStmt(const omega::CG_outputRepr *repr) {
    CHILL_ERROR("NOT IMPLEMENTED\n");
  }

  virtual int getStmtType(const omega::CG_outputRepr *repr) {
    CHILL_ERROR("NOT IMPLEMENTED\n");
    return 0;
  }

  virtual IR_OPERATION_TYPE getReductionOp(const omega::CG_outputRepr *repr) {
    CHILL_ERROR("NOT IMPLEMENTED\n");
    return IR_OP_MINUS;
  }

  virtual IR_Control *FromForStmt(const omega::CG_outputRepr *repr) {
    CHILL_ERROR("NOT IMPLEMENTED\n");
    return NULL;
  }

  // Manu:: Added functions for scalar expansion
  virtual IR_ArraySymbol *CreateArraySymbol(omega::CG_outputRepr *size, const IR_Symbol *sym) {
    CHILL_ERROR("NOT IMPLEMENTED\n");
    return NULL;
  }

  virtual bool ReplaceRHSExpression(omega::CG_outputRepr *code, IR_Ref *ref) {
    CHILL_ERROR("NOT IMPLEMENTED\n");
    return NULL;
  }

  virtual omega::CG_outputRepr *GetRHSExpression(omega::CG_outputRepr *code) {
    CHILL_ERROR("NOT IMPLEMENTED\n");
    return NULL;
  }

  virtual omega::CG_outputRepr *GetLHSExpression(omega::CG_outputRepr *code) {
    CHILL_ERROR("NOT IMPLEMENTED\n");
    return NULL;
  }

  virtual omega::CG_outputRepr *CreateMalloc(const IR_CONSTANT_TYPE type, std::string lhs,
                                             omega::CG_outputRepr *size_repr) {
    CHILL_ERROR("NOT IMPLEMENTED\n");
    return NULL;
  }

  virtual omega::CG_outputRepr *CreateMalloc(omega::CG_outputRepr *type, std::string variable,
                                             omega::CG_outputRepr *size_repr) {
    CHILL_ERROR("NOT IMPLEMENTED\n");
    return NULL;
  }

  virtual omega::CG_outputRepr *CreateFree(omega::CG_outputRepr *exp) {
    CHILL_ERROR("NOT IMPLEMENTED\n");
    return NULL;
  }

  //! Codegen Omega code builder interface
  omega::CG_outputBuilder *builder() const { return ocg_; }

};

#endif