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#ifndef __nanojit_RegAlloc__
#define __nanojit_RegAlloc__


namespace nanojit
{
	inline RegisterMask rmask(Register r)
	{
		return 1 << r;
	}

	class RegAlloc MMGC_SUBCLASS_DECL
	{
		public:
            RegAlloc() : free(0), used(0), priority(0) {}
			void	clear();
			bool	isFree(Register r); 
			void	addFree(Register r);
			void	addActive(Register r, LIns* ins);
            void    useActive(Register r);
			void	removeActive(Register r);
			void	retire(Register r);
            bool    isValid() {
                return (free|used) != 0;
            }

            int32_t getPriority(Register r) {
                NanoAssert(r != UnknownReg && active[r]);
                return usepri[r];
            }

	        LIns* getActive(Register r) {
		        NanoAssert(r != UnknownReg);
		        return active[r];
	        }

			debug_only( uint32_t	countFree(); )
			debug_only( uint32_t	countActive(); )
			debug_only( void		checkCount(); )
			debug_only( bool		isConsistent(Register r, LIns* v); )
			debug_only( uint32_t	count; )
			debug_only( RegisterMask managed; )    // bitfield of 0..NJ_MAX_REGISTERS denoting which are under our management                     

			LIns*	active[LastReg + 1];  // active[r] = OP that defines r
			int32_t usepri[LastReg + 1]; // used priority. lower = more likely to spill.
			RegisterMask	free;
			RegisterMask	used;
            int32_t         priority;

			verbose_only( static void formatRegisters(RegAlloc& regs, char* s, Fragment*); )

			DECLARE_PLATFORM_REGALLOC()
	};
}
#endif // __nanojit_RegAlloc__