GuardedDevirtualSnippet.hpp

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#ifndef GUARDEDDEVIRTUALSNIPPET_INCL
#define GUARDEDDEVIRTUALSNIPPET_INCL

#include <stddef.h>
#include <stdint.h>
#include "codegen/Snippet.hpp"
#include "x/codegen/RestartSnippet.hpp"

namespace TR { class Block; }
namespace TR { class CodeGenerator; }
namespace TR { class LabelSymbol; }
namespace TR { class MethodSymbol; }
namespace TR { class Node; }
namespace TR { class Register; }
namespace TR { class SymbolReference; }

namespace TR {

class X86GuardedDevirtualSnippet  : public TR::X86RestartSnippet
   {
   TR::Block    *_currentBlock;
   TR::Register *_classObjectRegister;
   int32_t      _vtableOffset;

   public:

   X86GuardedDevirtualSnippet(TR::CodeGenerator * cg,
                              TR::Node *          node,
                              TR::LabelSymbol     *restartlab,
                              TR::LabelSymbol     *snippetlab,
                              int32_t            vftoffset,
                              TR::Block          *currentBlock,
                              TR::Register       *classRegister);

   virtual Kind getKind() { return IsGuardedDevirtual; }

   int32_t getVTableOffset()             {return _vtableOffset;}
   int32_t setVTableOffset(int32_t vfto) {return (_vtableOffset = vfto);}

   TR::Register *getClassObjectRegister()                 {return _classObjectRegister;}
   TR::Register *setClassObjectRegister(TR::Register *reg) {return (_classObjectRegister = reg);}
   
   virtual bool isLoadArgumentsNecessary(TR::MethodSymbol *methodSymbol) {return false;}
   
   // Only implemented by AMD64GuardedDevirtualSnippet
   virtual TR::SymbolReference* getRealMethodSymbolReference() {return NULL;}

   virtual TR::X86GuardedDevirtualSnippet  *getGuardedDevirtualSnippet();

   virtual uint8_t *emitSnippetBody();

   virtual uint32_t getLength(int32_t estimatedSnippetStart);

   };

}

#endif