core/sql/optimizer/ItmFlowControlFunction.h

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#ifndef ItmFlowControlFunction_h
#define ItmFlowControlFunction_h

// Includes
//
#include "ItemFunc.h"
#include "ItemColRef.h"

// Forward External Declarations
//
class ItemExpr;
class BuiltinFunction;
class Generator;
class NAMemory;

// Forward Internal Declarations
//
class ItmDoWhileFunction;
class ItmBlockFunction;
class ItmExpressionVariable;
class ItmPersistentExpressionVariable;
class ItmWhileFunction;

class ItmDoWhileFunction : public BuiltinFunction 
{
public:
  ItmDoWhileFunction(ItemExpr *body, ItemExpr *condition)
    : BuiltinFunction(ITM_DO_WHILE,
                      CmpCommon::statementHeap(),
                      2, body, condition) { };

  virtual ~ItmDoWhileFunction() { };

  const NAType *synthesizeType();
  ItemExpr *preCodeGen(Generator*);
  short codeGen(Generator*);
  ItemExpr *copyTopNode(ItemExpr *derivedNode =NULL,
			NAMemory *outHeap =0);
};

class ItmBlockFunction : public BuiltinFunction {
public:
  ItmBlockFunction(ItemExpr *left, ItemExpr *right)
    : BuiltinFunction(ITM_BLOCK,
                      CmpCommon::statementHeap(),
                      2, left, right) { };

  virtual ~ItmBlockFunction() { };

  const NAType *synthesizeType();
  ItemExpr *preCodeGen(Generator*);
  short codeGen(Generator*);
  ItemExpr *copyTopNode(ItemExpr *derivedNode =NULL,
			NAMemory *outHeap =0);
};

class ItmExpressionVar : public HostVar
{
public:
  ItmExpressionVar(const NAType *type)
    : HostVar("_sys_ItmExpressionVariable", type, TRUE) { };

  virtual ~ItmExpressionVar() { };
};

class ItmPersistentExpressionVar : public ConstValue
{
public:
  ItmPersistentExpressionVar(Lng32 intVal)
    : ConstValue(intVal) { setConstFoldingDisabled(TRUE);};

  /*  ItmPersistentExpressionVar(NAType *type, 
			     NABoolean wantMinValue =FALSE, 
			     NABoolean allowNull =TRUE)
    : ConstValue(type, wantMinValue, allowNull) { };*/

  // Supply a type, a buffer containing the packed value,
  // the size of the buffer and , optionally, the string
  // for the literal (system-supplied version)
  ItmPersistentExpressionVar(const NAType *type, void *value, Lng32 value_len, 
			     NAString *literal = NULL)
    : ConstValue(type, value, value_len, literal) 
  { setConstFoldingDisabled(TRUE); }
  
  
  virtual ~ItmPersistentExpressionVar() { };

  short codeGen(Generator*);
};

class ItmWhileFunction : public BuiltinFunction 
{
public:
  ItmWhileFunction(ItemExpr *body, ItemExpr *condition)
    : BuiltinFunction(ITM_WHILE,
                      CmpCommon::statementHeap(),
                      2, body, condition) { };

  virtual ~ItmWhileFunction() {};

  const NAType *synthesizeType();
  ItemExpr *preCodeGen(Generator*);
  short codeGen(Generator*);
  ItemExpr *copyTopNode(ItemExpr *derivedNode =NULL,
			NAMemory *outHeap =0);
};

#endif