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#include "bid_internal.h"

BID_EXTERN_C double asinh(double);
BID_EXTERN_C double acosh(double);


BID_TYPE0_FUNCTION_ARGTYPE1(BID_UINT32, bid32_acosh, BID_UINT32, x)

  BID_UINT32 sign_x, coefficient_x, near_one, one;
  BID_UINT32 valid_x, res, z, z2;
  double xd, zd;
  int exponent_x, cmp_res;


  valid_x = unpack_BID32 (&sign_x, &exponent_x, &coefficient_x, x);

  if (!valid_x) {
    // test if x is NaN
if ((x & 0x7c000000) == 0x7c000000) {
#ifdef BID_SET_STATUS_FLAGS
  if ((x & 0x7e000000) == 0x7e000000)	// sNaN
    __set_status_flags (pfpsf, BID_INVALID_EXCEPTION);
#endif
	res = (coefficient_x) & QUIET_MASK32;
	BID_RETURN (res);
}
    // x is Infinity?
if ((x & 0x78000000) == 0x78000000) {
#ifdef BID_SET_STATUS_FLAGS
  if (sign_x)	// -Inf
    __set_status_flags (pfpsf, BID_INVALID_EXCEPTION);
#endif
      res = sign_x? 0x7c000000 : 0x78000000;
    BID_RETURN (res);
  }
    // x is 0
}
           
	 // calculate asinh(sqrt(x*x-1)) for x near 1 (x<1+1/32 = (10^5 + 5^5)/10^5 )
	 near_one = 0x300192d5;

	 BIDECIMAL_CALL2_NORND (bid32_quiet_less, 
            cmp_res, x, near_one);
	 if(cmp_res) {
		 // x<1+1/32
		one = 0x32800001; 

		BIDECIMAL_CALL2_NORND (bid32_quiet_greater, 
            cmp_res, one, x);
		if(cmp_res) {
			// x < 1
#ifdef BID_SET_STATUS_FLAGS
			__set_status_flags (pfpsf, BID_INVALID_EXCEPTION);
#endif
			res = 0x7c000000;
			BID_RETURN (res);
		}

		// -1
		one = 0xb2800001;

		// x*x-1
		BIDECIMAL_CALL3(bid32_fma, z2, x, x, one);
		// sqrt(x*x-1)
		BIDECIMAL_CALL1 (bid32_sqrt, z, z2);

		BIDECIMAL_CALL1 (bid32_to_binary64, xd, z);
		zd = asinh(xd);
		BIDECIMAL_CALL1 (binary64_to_bid32, res, zd);
		BID_RETURN (res);
	 }

  BIDECIMAL_CALL1(bid32_to_binary64,xd,x);
  zd = acosh(xd);
  BIDECIMAL_CALL1(binary64_to_bid32,res,zd);
  BID_RETURN (res);


}

