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  modification, are permitted provided that the following conditions are met:

    * Redistributions of source code must retain the above copyright notice,
      this list of conditions and the following disclaimer.
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      notice, this list of conditions and the following disclaimer in the
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      may be used to endorse or promote products derived from this software
      without specific prior written permission.

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  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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#include <stdio.h>
/* File: dpml_ux_inv_trig.c */
/*
**
**
**
**  Facility:
**
**	DPML
**
**  Abstract:
**
**	This file contains the code for computing the radian and degree
**	inverse trig functions of an unpacked x-float value.  In addition,
**	it contains the user interface code for the pack x-float inverse
**	trig functions and the mphoc code for building the class to action
**	table.
**
**  Modification History:
**
**	1-001	Original version.  RNH 21-Sep-95
**	1-002	atan(2q0) bug fix. GWK 20-Nov-98
**      1-003   Fixed problem with quotient estimation in atan2 when the
**              high digits of y and x are equal. RNH 19-Apr-02
**      1-004   Added special intel specific switch in class to
**              action map. Added class to action map for atan2 and atan2d
**              when y is -0. SBN 22-Apr-2002.    
**      1-005   Modified unpacked_result to array of 2 in C_UX_ATAN2.
**              SBN 24-Apr-2002. 
**      1-006   Added interface macros. SBN 29-Apr-2002.
**      1-007   Changed type of diff from unsigned to signed in quotient
**              estimation. SBN 30-Apr-2002. 
**      1-008   Modified interface macros. SBN 15-May-2002.
**
** Build Info:
**
**	Preprocess this file with MAKE_INCLUDE defined to produce a .h
**	file containing the class-to-action map and appropriate constants
**	for the inverse trig functions.  Then compile this file with *NO*
**	defines to get the code for inverse trig functions.
*/

#define	BASE_NAME	inv_trig
#include "dpml_ux.h"

#if !defined(MAKE_INCLUDE)
#   include STR(BUILD_FILE_NAME)
#endif


/* 
** 1. BASIC DESIGN/ALGORITHMS
** --------------------------
** 
** The basic design of for the inverse trig functions relies on two evaluation
** routines, one for the atan family of functions and one for the asin/acos
** family.  Within each family, the differences between the degree and radian
** versions are handled by multiplying the radian result by 180/pi to get
** the degree result before rounding back to X_FLOAT precision.  It is possible
** to account for the radian/degree differences by using different sets of
** constants.  In order to discuss some of the design issues independent of the
** choice mechanism for dealing with the radian/degree differences, we will use
** the symbolic name CYCLE to refer to 180 or pi.
** 
** 
** 1.1 ATAN
** --------
** 
** We note that the atan(x) = atan2(x,1), so we will confine most of the
** discussion to the atan2 case.  The basic algorithm makes use of the
** following identities:
** 
** 		atan2(-y,x) = - atan2(y,x)			(1)
** 		atan2(y,-x) = CYCLE - atan(y,x)			(2)
** 		atan2(y, x) = atan(y/x)	x,y >= 0		(3)
** 		atan(z) = atan(a) + atan[(z - a)/(1 + a*z)	(4)
** 		atan(1/z) = CYCLE/2 - atan(z)			(5)
** 
** Items (1) through (3) imply that for the most part we need only deal with
** |y/x|.  In particular, based on the above we make the following definitions
** of i, C(i), S(i) and z(i), according to the size of |y/x|:
** 
** 	Size of |y/x|	 i	  c(i)	  s(i)        z(i)
** 	-------------	---	--------- ---- ------------------
** 	[0, 1/2)	 0	    0	    1         |y/x|
** 	[1/2, 2]	 1	 CYCLE/4    1  (|y|-|x|)/(|y|+|x|)
** 	(2, Inf)	 2	 CYCLE/2   -1         |x/y|
** 
** From which it follows that:
** 
** 		atan2(|y|,|x|) = c(i) + s(i)*atan(z(i))
** 
** where 0 <= z(i) < 1/2.  Using (2) we can extend the above table for negative
** x as
** 	Size of |y/x|	 i	   c(i)	  s(i)        z(i)
** 	--------------	---	--------- ---- ------------------
** 	[0, 1/2) x < 0	 3	CYCLE	   -1         |y/x|
** 	[1/2, 2] x < 0	 4	3*CYCLE/4  -1  (|y|-|x|)/(|y|+|x|)
** 	(2, Inf) x < 0	 5	CYCLE/2	    1         |x/y|
** 
** Finally, using (1) we have
** 
** 		atan2(y,x) = sign(y)*[c(i) + s(i)*atan(z(i))]
** 
** Based on the above, the general approach to evaluating atan2(y,x) is: 
** 
** 	(a) compute the exponent value, n, of y/x
** 	(b) Based on n and the sign of x, compute the index i, and the
** 	    value z(i).
** 	(c) compute atan(z(i)) using a rational approximation (see section
** 	    2)
** 	(d) based on i, compute c(i) + atan(z(i)) or c(i) - atan(z(i))
** 	(e) copy the sign of y onto the last result.
** 
** At this point we would like to discuss step (d) in more detail.  We note
** the following:
** 
** 		o c(i) = (i/4)*CYCLE      for i = 0, 1, 2
** 		o c(i+3) = (4-i)/4]*CYCLE for i = 0, 1, 2
** 		o s(i+3) = -s(i)          for i = 0, 1, 2
** 
** This implies that during the screening to determine the interval, we can
** determine c(i) and s(i) for i = 0, 1, or 2 and then adjust c(i) and s(i)
** to reflect the sign of x.  
** 
** 
** EVALUATE_RATIONAL depends on the reduced argument x satisfying
** |x| < 1 , and the coefficients decreasing.  If the coefficients
** don't decrease, shifting the exponent of the reduced argument 
** (effectively multiplying by 2, 4, or more) and pulling this factor
** out of the coefficients can then allow them to decrease.
** For atan, the reduced argument has its exponent shifted by 1,
** which effectively mutliplies it by 2.  If the argument is
** exactly 1/2, the shift makes it 1, and EVALUATE_RATIONAL won't work.
** So, we want to avoid a reduced argument of 1/2 for atan. 
**
** In order to call the polynomial evaluation routine with
** a reduced argument strictly less than 1/2 we check the
** value of the reduced argument after |y/x| is calculated.
**
** But rather than calculate |y/x|, its value is estimated by 
** calculating its exponentt.  The value of this exponent
** determines which of |y/x|, (|y|-|x|)/(|y|+|x|), or |x/y| is
** actually calculated and used as the reduced argument.  
** When the exponent is >1, the value is >= 2, and |x/y| is
** calculated as the reduced argument.  But if |y/x| is
** exactly = 2, |x/y| = 1/2, which should not be sent to the polynomial
** evaluation routine.
** So, the un-normalized exponent is checked, and decremented 
** if the most significant bit of the fraction field is 0.
** If the exponent is still >= 0, the initial reduced_argument = 1/2,
** so we want to use (|y|-|x|)/(|y|+|x|) = 1/3 instead
** To make this so:
**   (1) decrement the index
**   (2) un-toggle the sign bit
**   (3) change the reduced argument to 1/3 (via a table entry)
** 
** 
** 
** 2. ATAN/ATAN2 EVALUATION
** ------------------------
** 
** The atan family of functions call a common routine to unpack their arguments
** and invoke the evaluation routine UX_ATAN2.  For atan and atand, the 'x'
** argument passed to UX_ATAN2 is a null pointer.  UX_ATAN2 uses the null
** pointer to distinguish between an atan evaluation and an atan2 evaluation.
** Also, the null pointer is passed onto the divide routine, where it is
** implicitly treated as a pointer to the value 1.  In this way, very little
** special casing is required for atan cases being processed by UX_ATAN2.
*/ 

#if !defined(UX_ATAN2)
#   define UX_ATAN2	__INTERNAL_NAME(ux_atan2__)
#endif

#define DEGREE_EVALUATION	((WORD) 1 << (BITS_PER_WORD - 1))
#define RADIAN_EVALUATION	0

#define ATAN_MAP_WIDTH		4
#define ATAN_MAP_FIELD(i,c)	((c) << ((i)*ATAN_MAP_WIDTH))
#define INV_TRIG_CONS(index)	\
		(UX_FLOAT *)((char *) INV_TRIG_CONS_BASE + (index))



void
UX_ATAN2(
  UX_FLOAT * unpacked_y,
  UX_FLOAT * unpacked_x,
  WORD       degree_radian_flag,
  UX_FLOAT * unpacked_result)
    {
    UX_FLOAT         tmp[2], red_arg, *aux_x, *tmp_ptr;
    WORD             index;
    UX_SIGN_TYPE     sign, sign_y;
    UX_EXPONENT_TYPE quotient_exp;
    UX_SIGNED_FRACTION_DIGIT_TYPE diff;

    /* Determine (estimate ?) the exponent of y/x */

    if (0 == unpacked_x)
        { /* This is a atan, rather than atan2 function */
        quotient_exp = G_UX_EXPONENT(unpacked_y);
        aux_x = UX_ONE;
        sign = 0;
        }
    else
        {
        quotient_exp = G_UX_EXPONENT(unpacked_y) - G_UX_EXPONENT(unpacked_x);
        aux_x = unpacked_x;
        sign = G_UX_SIGN(unpacked_x);
        P_UX_SIGN(unpacked_x, 0);
        diff = G_UX_MSD(unpacked_y) - G_UX_MSD(unpacked_x);
        if ( quotient_exp >= 0 )
        quotient_exp -= (diff == 0 && quotient_exp > 0 );
        quotient_exp += (diff >= 0);
        }

    /* Do argument reduction */

    index = sign ? 3*ATAN_MAP_WIDTH : 0;
    sign_y = G_UX_SIGN(unpacked_y);
    P_UX_SIGN(unpacked_y, 0);

    if (quotient_exp > 1)
        { /* reduced argument is x/y */
        index += 2*ATAN_MAP_WIDTH;
        tmp_ptr = unpacked_x;
        unpacked_x = unpacked_y;
        unpacked_y = tmp_ptr;
        sign ^= UX_SIGN_BIT;
        }
    else if (quotient_exp >= 0)
        { /* reduced argument is (y-x)/(y+x) */
        index += ATAN_MAP_WIDTH;
        ADDSUB(unpacked_y, aux_x,
          ADD_SUB | MAGNITUDE_ONLY | NO_NORMALIZATION, tmp);
        unpacked_y = &tmp[1];
        unpacked_x = &tmp[0];
        NORMALIZE(unpacked_y);
        }

    DIVIDE(unpacked_y, unpacked_x, FULL_PRECISION, &red_arg);

    /* force reduced argument to be less than 1/2 */

    quotient_exp = red_arg.exponent;
    if ( (UX_MSB & red_arg.fraction[0])  == 0) quotient_exp--;
    if ( quotient_exp >= 0 )
        {
        index -= ATAN_MAP_WIDTH;
        sign ^= UX_SIGN_BIT;
        red_arg = *UX_ONE_THIRD;
        }

    /* Evaluate the reduced argument */

    EVALUATE_RATIONAL(
        &red_arg,
        ATAN_COEF_ARRAY,
        ATAN_COEF_ARRAY_DEGREE,
        NUMERATOR_FLAGS(SQUARE_TERM | POST_MULTIPLY) |
          DENOMINATOR_FLAGS(SQUARE_TERM) | P_SCALE(1),
        unpacked_result);
 
    /* Add in the appropriate constant */

    UX_TOGGLE_SIGN(unpacked_result, sign);
    if (index)
        {
        index =
          ((ATAN_MAP_FIELD( 0, UX_ZERO_INDEX )            	+
            ATAN_MAP_FIELD( 1, UX_PI_OVER_4_INDEX )       	+
            ATAN_MAP_FIELD( 2, UX_PI_OVER_2_INDEX )      	+
            ATAN_MAP_FIELD( 3, UX_PI_INDEX )			+
            ATAN_MAP_FIELD( 4, UX_THREE_QUARTERS_PI_INDEX )	+
            ATAN_MAP_FIELD( 5, UX_PI_OVER_2_INDEX ) ) >> index) & 
            MAKE_MASK(ATAN_MAP_WIDTH, 3);

        NORMALIZE(unpacked_result);
        ADDSUB(
            INV_TRIG_CONS(index),
            unpacked_result,
            ADD | NO_NORMALIZATION,
            unpacked_result);
        }

    /* Convert to degrees if necessary */

    if (DEGREE_EVALUATION == degree_radian_flag)
        MULTIPLY( UX_RAD_TO_DEG, unpacked_result, unpacked_result);

    /* Determine final sign and return */

    P_UX_SIGN(unpacked_result, sign_y);
    return;
    }

/*
** C_UX_ATAN2 is the common processing routine for atanl, atan2l, atandl and
** atan2dl.  C_UX_ATAN2 unpacks the input arguments, calls UX_ATAN2 and then
** packs the results
*/

#if !defined(C_UX_ATAN2)
#   define C_UX_ATAN2	__INTERNAL_NAME(C_ux_atan2__)
#endif

static void
C_UX_ATAN2 (
  _X_FLOAT     * packed_y,
  _X_FLOAT     * packed_x,
  WORD           degree_radian_flag,
  U_WORD const * class_to_action_map,
  WORD           underflow_error,
  _X_FLOAT     * packed_result
  OPT_EXCEPTION_INFO_DECLARATION )
    {
    WORD    fp_class;
    UX_FLOAT unpacked_x, unpacked_y, unpacked_result[2];

    fp_class  = UNPACK2(
        packed_y,
        packed_x,
        & unpacked_y,
        & unpacked_x,
        class_to_action_map,
        packed_result
        OPT_EXCEPTION_INFO_ARGUMENT );

    if (0 > fp_class)
        return;

    UX_ATAN2(
        &unpacked_y,
        packed_x ? &unpacked_x : 0,
        degree_radian_flag,
        &unpacked_result[0]);

    PACK(
        &unpacked_result[0],
        packed_result,
        underflow_error,
        NOT_USED
        OPT_EXCEPTION_INFO_ARGUMENT );
    }

/*
** The following routines are the user level interfaces to the packed x-float
** atan family of routines
*/

#undef  F_ENTRY_NAME
#define F_ENTRY_NAME	F_ATAN_NAME

X_X_PROTO(F_ENTRY_NAME, packed_result, packed_x)
    {
    EXCEPTION_INFO_DECL
    DECLARE_X_FLOAT(packed_result)

    INIT_EXCEPTION_INFO;
    C_UX_ATAN2(
        PASS_ARG_X_FLOAT(packed_x),
	NULL,
        RADIAN_EVALUATION,
        ATAN_CLASS_TO_ACTION_MAP,
        NOT_USED,
        PASS_RET_X_FLOAT(packed_result)
        OPT_EXCEPTION_INFO );

    RETURN_X_FLOAT(packed_result);

    }


#undef  F_ENTRY_NAME
#define F_ENTRY_NAME	F_ATAN2_NAME

X_XX_PROTO(F_ENTRY_NAME, packed_result, packed_y, packed_x)
    {
    EXCEPTION_INFO_DECL
    DECLARE_X_FLOAT(packed_result)

    INIT_EXCEPTION_INFO;
    C_UX_ATAN2(
        PASS_ARG_X_FLOAT(packed_y),
    PASS_ARG_X_FLOAT(packed_x),
        RADIAN_EVALUATION,
        ATAN2_CLASS_TO_ACTION_MAP,
        ATAN2_UNDERFLOW,
        PASS_RET_X_FLOAT(packed_result)
        OPT_EXCEPTION_INFO );

    RETURN_X_FLOAT(packed_result);

    }

#undef  F_ENTRY_NAME
#define F_ENTRY_NAME	F_ATAND_NAME

X_X_PROTO(F_ENTRY_NAME, packed_result, packed_x)
    {
    EXCEPTION_INFO_DECL
    DECLARE_X_FLOAT(packed_result)

    INIT_EXCEPTION_INFO;
    C_UX_ATAN2(
        PASS_ARG_X_FLOAT(packed_x),
	NULL,
        DEGREE_EVALUATION,
        ATAND_CLASS_TO_ACTION_MAP,
        NOT_USED,
        PASS_RET_X_FLOAT(packed_result)
        OPT_EXCEPTION_INFO );

    RETURN_X_FLOAT(packed_result);

    }

#undef  F_ENTRY_NAME
#define F_ENTRY_NAME	F_ATAND2_NAME

X_XX_PROTO(F_ENTRY_NAME, packed_result, packed_y, packed_x)
    {
    EXCEPTION_INFO_DECL
    DECLARE_X_FLOAT(packed_result)

    INIT_EXCEPTION_INFO;
    C_UX_ATAN2(
        PASS_ARG_X_FLOAT(packed_y),
    PASS_ARG_X_FLOAT(packed_x),
        DEGREE_EVALUATION,
        ATAND2_CLASS_TO_ACTION_MAP,
        ATAND2_UNDERFLOW,
        PASS_RET_X_FLOAT(packed_result)
        OPT_EXCEPTION_INFO );

    RETURN_X_FLOAT(packed_result);

    }

/* 
** 3.0 ASIN/ACOS
** -------------
** 
** The overall design for the asin/acos functions is remarkably similar to the
** atan functions.  The asin/acos evaluations are based on the following
** identities:
** 
** 		asin(-x) = -asin(x)				(1)
** 		asin(x)  = CYCLE/2 - 2*asin(sqrt((1-x)/2))	(2)
** 		acos(x)  = CYCLE/2 - asin(x)			(3)
** 
** As for atan, based on the above identities and the size of x, we can define
** quantities i, j, c(i), s(i), t(i) and z(i) such that
** 
** 	asin(x) or acos(x) = s(i)*[ c(i) + t(i)*2^j*asin(z(i))]
** 
** 
** 	Function      x	     i	s(i)    c(i)  t(i)  j     z(i)
** 	-------- ---------- ---	---- -------- ---- --- ------------------
** 	  asin   [-1, -1/2)  3   -1   CYCLE/2  -1   1  sqrt((1-|x|)/2)
** 	         [-1/2, 0)   2   -1      0      1   0       |x|
** 	         [0, 1/2)    0    1      0      1   0       |x|
** 	         [1/2, 1)    1    1   CYCLE/2  -1   1  sqrt((1-|x|)/2)
** 
** 	  acos   [-1, -1/2)  3    1    CYCLE   -1   1  sqrt((1-|x|)/2)
** 	         [-1/2, 0)   2    1   CYCLE/2   1   0       |x|
** 	         [0, 1/2)    0    1   CYCLE/2  -1   0       |x|
** 	         [1/2, 1)    1    1      0      1   1  sqrt((1-|x|)/2)
** 
** With the above in mind, the general approach to evaluating asin or acos is: 
** 
** 	(a) Based on the exponent and sign of x, compute the index i, and the
** 	    values of j and z(i).
** 	(b) compute w = asin(z(i)) using a rational approximation (see section
** 	    2)
** 	(c) increment the exponent of w by j.
** 	(d) based on i, compute s(i)*[c(i) + t(i)*w]
** 
** The algorithm for determining s(i), t(i) and c(i) for asin and acos is more
** complicated, so we resort to a "table look-up" scheme.  That is, We assume
** that there will be a array of _UX_FLOAT constants that contains the values
** CYCLE/4, CYCLE/2, 3*CYCLE/4 and CYCLE.  For each i in step (b), we can
** allocate a 7 bit field within a U_INT_32 value that encodes the index of
** c(i) in the constant table and the values of s(i) and t(i).  This allocation
** can be done at compile time, so that at run time, step (d) consists of
** accessing the appropriate 7 bit field and extracting s(i), t(i) and the
** index for c(i).  We assume that the 7 bit fields are allocated as
** 
** 		        7          2  1  0
** 			 +----------+--+--+
** 			 |  index   | s| t|
** 			 +----------+--+--+
** 
** with the first field starting at bit 4.  We further assume that the bit 0 is
** one for a degree evaluation and 0 otherwise.
** 
** 
** 4. ATAN AND ASIN EVALUATION
** ---------------------------
** 
** Both atan and asin are more efficiently evaluated using rational
** approximations than polynomial evaluations.  Extrapolating from the tables
** in Hart and the current x-float asin polynomial, the number of terms in a
** polynomial and a rational approximations are:
** 
** 		Function	polynomial	rational
** 		--------	----------	--------
** 		  asin		    32		 (10,10)
** 		  atan		    30		 (10,10)
** 
** 5. ASIN/ACOS EVALUATION
** -----------------------
** 
** Since asin and acos do not require unpacked interfaces, the user level
** routines do not unpack their arguments.  Instead they simply pass them on to
** the general asin/acos evaluation routine, UX_ASIN_ACOS.  The interface
** to UX_ASIN_ACOS is:
** 
** 	static void
** 	UX_ASIN_ACOS(
** 	    _X_FLOAT     * packed_argument,
** 	    WORD           index_map,
**          WORD           invalid_error,
**          U_WORD const * class_to_action_map,
** 	    _X_FLOAT     * packed_result);
** 
** where: 'index_map' is the 32 bit data item used to encode the c(i)'s, s(i)'s
** and t(i)'s defined in section 1; 'invalid_error' is the error code for the
** indicated error and 'class_to_action_array' is the mapping array for the
** given function.
*/ 


#define BIT_FROM_MAP(m,i)	(((m) << (BITS_PER_WORD - (i))) & UX_SIGN_BIT)

#define ASIN_MAP_WIDTH	6
#define ASIN_MAP_FIELD(i,c,t,s)	(((c) + 8*(t) + 4*(s)) << ((i)*ASIN_MAP_WIDTH))
#define G_MAP_INFO(m,i)		((m) >> (i))
#define G_S_FROM_ASIN_MAP(m)	((m & 4) ? UX_SIGN_BIT : 0 )
#define G_T_FROM_ASIN_MAP(m)	((m & 8) ? UX_SIGN_BIT : 0 )
#define G_C_FROM_ASIN_MAP(m)	INV_TRIG_CONS((m) & 0xf0)

#if !defined(UX_ASIN_ACOS)
#   define UX_ASIN_ACOS		__INTERNAL_NAME(ux_asin_acos__)
#endif

static void
UX_ASIN_ACOS(
  _X_FLOAT     * packed_argument,
  WORD           index_map,
  WORD           invalid_error,
  U_WORD const * class_to_action_map,
  _X_FLOAT     * packed_result
  OPT_EXCEPTION_INFO_DECLARATION )
    {
    WORD             fp_class, index, map;
    UX_FLOAT         * unpacked_argument, * unpacked_result, tmp[3];
    UX_SIGN_TYPE     sign;
    UX_EXPONENT_TYPE exponent, exponent_inc;

    unpacked_argument = &tmp[0];
    unpacked_result   = &tmp[1];

    fp_class  = UNPACK(
        packed_argument,
        unpacked_argument,
        class_to_action_map,
        packed_result
        OPT_EXCEPTION_INFO_ARGUMENT );

    if (0 > fp_class)
        return;

    /*
    ** Determine the index based on size of x and sign(x).  Also
    ** screen out arguments |x| > 1.
    */

    exponent = G_UX_EXPONENT(unpacked_argument);
    exponent_inc = 0;
    index = G_UX_SIGN( unpacked_argument) ? 2*ASIN_MAP_WIDTH : 0;
    P_UX_SIGN( unpacked_argument, 0);

    if (exponent >= 0)
        { /* |x| >= 1/2 */

        index += ASIN_MAP_WIDTH;
        if (exponent < 1)
            { /* 1/2 <= |argument| < 1, compute sqrt((1-x)/2) */
            exponent_inc = 1;
            ADDSUB( UX_ONE, unpacked_argument, SUB | MAGNITUDE_ONLY,
              unpacked_argument);
            UX_DECR_EXPONENT( unpacked_argument, 1);
            UX_SQRT( unpacked_argument, unpacked_argument);
            }

        /* separate |x| = 1 from |x| > 1 */

        else if ((exponent == 1) && UX_FRACTION_IS_ONE_HALF(unpacked_argument))

            /* |x| = 1, make "reduced argument" zero */
            UX_COPY(UX_ZERO, unpacked_argument);

        else
            { /* Force "overflow" to signal error */
            UX_SET_SIGN_EXP_MSD(unpacked_result, 0,
              UX_OVERFLOW_EXPONENT, UX_MSB);
            goto pack_it;
            }
        }

    EVALUATE_RATIONAL(
        unpacked_argument,
        ASIN_COEF_ARRAY,
        ASIN_COEF_ARRAY_DEGREE,
        NUMERATOR_FLAGS(SQUARE_TERM | POST_MULTIPLY | ALTERNATE_SIGN) |
          DENOMINATOR_FLAGS(SQUARE_TERM | ALTERNATE_SIGN) |
          P_SCALE(1),
        unpacked_result);

     /*
     ** Set sign for polynomial evaluation and scale by 2 if needed
     */

     index = G_MAP_INFO(index_map, index);
     P_UX_SIGN( unpacked_result, G_T_FROM_ASIN_MAP(index));
     UX_INCR_EXPONENT( unpacked_result, exponent_inc);

     /* Add in c(i) */

     ADDSUB( G_C_FROM_ASIN_MAP(index), unpacked_result,
       ADD | NO_NORMALIZATION, unpacked_result);

     /* Set sign of result and convert to degrees */

     P_UX_SIGN( unpacked_result, G_S_FROM_ASIN_MAP(index) );
     if (index_map & DEGREE_EVALUATION)
         MULTIPLY( unpacked_result, UX_RAD_TO_DEG, unpacked_result);

pack_it:
    PACK(
        unpacked_result,
        packed_result,
        NOT_USED,
        invalid_error
        OPT_EXCEPTION_INFO_ARGUMENT );
    }


/*
** The following routines are the user level interfaces to the packed
** asin, acos, asind and acosd routines.
*/

#undef  F_ENTRY_NAME
#define	F_ENTRY_NAME	F_ASIN_NAME

         		             /* Interval   Constant Index    t  s */
#define ASIN_INTERVAL_MAP ( ASIN_MAP_FIELD( 3,   UX_PI_OVER_2_INDEX, 1, 1) + \
			    ASIN_MAP_FIELD( 2,     UX_ZERO_INDEX,    0, 1) + \
			    ASIN_MAP_FIELD( 0,     UX_ZERO_INDEX,    0, 0) + \
			    ASIN_MAP_FIELD( 1,   UX_PI_OVER_2_INDEX, 1, 0) )

				     /* Interval    Constant Index    t  s */
#define ACOS_INTERVAL_MAP ( ASIN_MAP_FIELD( 3,        UX_PI_INDEX,    1, 0) + \
			    ASIN_MAP_FIELD( 2,    UX_PI_OVER_2_INDEX, 0, 0) + \
			    ASIN_MAP_FIELD( 0,    UX_PI_OVER_2_INDEX, 1, 0) + \
			    ASIN_MAP_FIELD( 1,       UX_ZERO_INDEX,   0, 0) )

X_X_PROTO(F_ENTRY_NAME, packed_result, packed_argument)
    {
    EXCEPTION_INFO_DECL
    DECLARE_X_FLOAT(packed_result)

    INIT_EXCEPTION_INFO;
    UX_ASIN_ACOS(
         PASS_ARG_X_FLOAT(packed_argument),
         ASIN_INTERVAL_MAP + RADIAN_EVALUATION,
         ASIN_ARG_GT_ONE,
         ASIN_CLASS_TO_ACTION_MAP,
         PASS_RET_X_FLOAT(packed_result)
         OPT_EXCEPTION_INFO );

    RETURN_X_FLOAT(packed_result);

    }

#undef  F_ENTRY_NAME
#define	F_ENTRY_NAME	F_ASIND_NAME

X_X_PROTO(F_ENTRY_NAME, packed_result, packed_argument)
    {
    EXCEPTION_INFO_DECL
    DECLARE_X_FLOAT(packed_result)

    INIT_EXCEPTION_INFO;
    UX_ASIN_ACOS(
         PASS_ARG_X_FLOAT(packed_argument),
         ASIN_INTERVAL_MAP + DEGREE_EVALUATION,
         ASIN_ARG_GT_ONE,
         ASIND_CLASS_TO_ACTION_MAP,
         PASS_RET_X_FLOAT(packed_result)
         OPT_EXCEPTION_INFO );

    RETURN_X_FLOAT(packed_result);

    }

#undef  F_ENTRY_NAME
#define	F_ENTRY_NAME	F_ACOS_NAME

X_X_PROTO(F_ENTRY_NAME, packed_result, packed_argument)
    {
    EXCEPTION_INFO_DECL
    DECLARE_X_FLOAT(packed_result)

    INIT_EXCEPTION_INFO;
    UX_ASIN_ACOS(
         PASS_ARG_X_FLOAT(packed_argument),
         ACOS_INTERVAL_MAP + RADIAN_EVALUATION,
         ASIN_ARG_GT_ONE,
         ACOS_CLASS_TO_ACTION_MAP,
         PASS_RET_X_FLOAT(packed_result)
         OPT_EXCEPTION_INFO );

    RETURN_X_FLOAT(packed_result);

    }

#undef  F_ENTRY_NAME
#define	F_ENTRY_NAME	F_ACOSD_NAME

X_X_PROTO(F_ENTRY_NAME, packed_result, packed_argument)
    {
    EXCEPTION_INFO_DECL
    DECLARE_X_FLOAT(packed_result)

    INIT_EXCEPTION_INFO;
    UX_ASIN_ACOS(
         PASS_ARG_X_FLOAT(packed_argument),
         ACOS_INTERVAL_MAP + DEGREE_EVALUATION,
         ACOSD_ARG_GT_ONE,
         ACOSD_CLASS_TO_ACTION_MAP,
         PASS_RET_X_FLOAT(packed_result)
         OPT_EXCEPTION_INFO );

    RETURN_X_FLOAT(packed_result);

    }


/*
** MPHOC code for generatings the class-to-action mappings, rational
** coefficients and miscellaneous constants.
*/

#if defined(MAKE_INCLUDE)

    @divert -append divertText

    precision = ceil(UX_PRECISION/8) + 4;

#   undef  TABLE_NAME

    START_TABLE;

    TABLE_COMMENT("asin class-to-action-mapping");
    PRINT_CLASS_TO_ACTION_TBL_DEF( "ASIN_CLASS_TO_ACTION_MAP");
    PRINT_64_TBL_ITEM(  CLASS_TO_ACTION_DISP(1) +
	      CLASS_TO_ACTION( F_C_SIG_NAN,    RETURN_QUIET_NAN, 0) +
              CLASS_TO_ACTION( F_C_QUIET_NAN,  RETURN_VALUE,     0) +
              CLASS_TO_ACTION( F_C_POS_INF,    RETURN_ERROR,     1) +
              CLASS_TO_ACTION( F_C_NEG_INF,    RETURN_ERROR,     1) +
              CLASS_TO_ACTION( F_C_POS_DENORM, RETURN_VALUE,     0) +
              CLASS_TO_ACTION( F_C_NEG_DENORM, RETURN_VALUE,     0) +
              CLASS_TO_ACTION( F_C_POS_ZERO,   RETURN_VALUE,     0) +
              CLASS_TO_ACTION( F_C_NEG_ZERO ,  RETURN_VALUE,     0) );
        PRINT_U_TBL_ITEM( /* data 1 */ ASIN_ARG_GT_ONE );


    TABLE_COMMENT("acos class-to-action-mapping");
    PRINT_CLASS_TO_ACTION_TBL_DEF( "ACOS_CLASS_TO_ACTION_MAP");
    PRINT_64_TBL_ITEM(  CLASS_TO_ACTION_DISP(1) +
	      CLASS_TO_ACTION( F_C_SIG_NAN,    RETURN_QUIET_NAN, 0) +
              CLASS_TO_ACTION( F_C_QUIET_NAN,  RETURN_VALUE,     0) +
              CLASS_TO_ACTION( F_C_POS_INF,    RETURN_ERROR,     1) +
              CLASS_TO_ACTION( F_C_NEG_INF,    RETURN_ERROR,     1) +
              CLASS_TO_ACTION( F_C_POS_DENORM, RETURN_VALUE,     2) +
              CLASS_TO_ACTION( F_C_NEG_DENORM, RETURN_VALUE,     2) +
              CLASS_TO_ACTION( F_C_POS_ZERO,   RETURN_VALUE,     2) +
              CLASS_TO_ACTION( F_C_NEG_ZERO ,  RETURN_VALUE,     2) );
        PRINT_U_TBL_ITEM( /* data 1 */ ACOS_ARG_GT_ONE );
        PRINT_U_TBL_ITEM( /* data 2 */ PI_OVER_2 );

    TABLE_COMMENT("asind class-to-action-mapping");
    PRINT_CLASS_TO_ACTION_TBL_DEF( "ASIND_CLASS_TO_ACTION_MAP");
    PRINT_64_TBL_ITEM(  CLASS_TO_ACTION_DISP(1) +
	      CLASS_TO_ACTION( F_C_SIG_NAN,    RETURN_QUIET_NAN, 0) +
              CLASS_TO_ACTION( F_C_QUIET_NAN,  RETURN_VALUE,     0) +
              CLASS_TO_ACTION( F_C_POS_INF,    RETURN_ERROR,     1) +
              CLASS_TO_ACTION( F_C_NEG_INF,    RETURN_ERROR,     1) +
              CLASS_TO_ACTION( F_C_POS_DENORM, RETURN_UNPACKED,  0) +
              CLASS_TO_ACTION( F_C_NEG_DENORM, RETURN_UNPACKED,  0) +
              CLASS_TO_ACTION( F_C_POS_ZERO,   RETURN_VALUE,     0) +
              CLASS_TO_ACTION( F_C_NEG_ZERO ,  RETURN_VALUE,     0) );
        PRINT_U_TBL_ITEM( /* data 1 */ ASIND_ARG_GT_ONE );


    TABLE_COMMENT("acosd class-to-action-mapping");
    PRINT_CLASS_TO_ACTION_TBL_DEF( "ACOSD_CLASS_TO_ACTION_MAP");
    PRINT_64_TBL_ITEM(  CLASS_TO_ACTION_DISP(1) +
	      CLASS_TO_ACTION( F_C_SIG_NAN,    RETURN_QUIET_NAN, 0) +
              CLASS_TO_ACTION( F_C_QUIET_NAN,  RETURN_VALUE,     0) +
              CLASS_TO_ACTION( F_C_POS_INF,    RETURN_ERROR,     1) +
              CLASS_TO_ACTION( F_C_NEG_INF,    RETURN_ERROR,     1) +
              CLASS_TO_ACTION( F_C_POS_DENORM, RETURN_VALUE,     2) +
              CLASS_TO_ACTION( F_C_NEG_DENORM, RETURN_VALUE,     2) +
              CLASS_TO_ACTION( F_C_POS_ZERO,   RETURN_VALUE,     2) +
              CLASS_TO_ACTION( F_C_NEG_ZERO ,  RETURN_VALUE,     2) );
        PRINT_U_TBL_ITEM( /* data 1 */ ACOSD_ARG_GT_ONE );
        PRINT_U_TBL_ITEM( /* data 2 */ NINETY );


    TABLE_COMMENT("atan class-to-action-mapping");
    PRINT_CLASS_TO_ACTION_TBL_DEF( "ATAN_CLASS_TO_ACTION_MAP");
    PRINT_64_TBL_ITEM(  CLASS_TO_ACTION_DISP(1) +
	      CLASS_TO_ACTION( F_C_SIG_NAN,    RETURN_QUIET_NAN, 0) +
              CLASS_TO_ACTION( F_C_QUIET_NAN,  RETURN_VALUE,     0) +
              CLASS_TO_ACTION( F_C_POS_INF,    RETURN_VALUE,     1) +
              CLASS_TO_ACTION( F_C_NEG_INF,    RETURN_NEGATIVE,  1) +
              CLASS_TO_ACTION( F_C_POS_DENORM, RETURN_VALUE,     0) +
              CLASS_TO_ACTION( F_C_NEG_DENORM, RETURN_VALUE,     0) +
              CLASS_TO_ACTION( F_C_POS_ZERO,   RETURN_VALUE,     0) +
              CLASS_TO_ACTION( F_C_NEG_ZERO ,  RETURN_VALUE,     0) );
        PRINT_U_TBL_ITEM( /* data 1 */ PI_OVER_2 );

    TABLE_COMMENT("atand class-to-action-mapping");
    PRINT_CLASS_TO_ACTION_TBL_DEF( "ATAND_CLASS_TO_ACTION_MAP");
    PRINT_64_TBL_ITEM(  CLASS_TO_ACTION_DISP(1) +
	      CLASS_TO_ACTION( F_C_SIG_NAN,    RETURN_QUIET_NAN, 0) +
              CLASS_TO_ACTION( F_C_QUIET_NAN,  RETURN_VALUE,     0) +
              CLASS_TO_ACTION( F_C_POS_INF,    RETURN_VALUE,     1) +
              CLASS_TO_ACTION( F_C_NEG_INF,    RETURN_NEGATIVE,  1) +
              CLASS_TO_ACTION( F_C_POS_ZERO,   RETURN_VALUE,     0) +
              CLASS_TO_ACTION( F_C_NEG_ZERO ,  RETURN_VALUE,     0) );
        PRINT_U_TBL_ITEM( /* data 1 */ NINETY );


    TABLE_COMMENT("atan2(y,x) class-to-action-mapping");
    PRINT_CLASS_TO_ACTION_TBL_DEF( "ATAN2_CLASS_TO_ACTION_MAP");

	  /* Index 0: class-to-action for y */

    PRINT_64_TBL_ITEM( CLASS_TO_ACTION_DISP(8) +
	      CLASS_TO_ACTION( F_C_SIG_NAN,    RETURN_QUIET_NAN, 0) +
              CLASS_TO_ACTION( F_C_QUIET_NAN,  RETURN_VALUE,     0) );

	   /* Index 1: class-to-index mapping */

    PRINT_64_TBL_ITEM( 
	       CLASS_TO_INDEX( F_C_POS_INF,    2) +
	       CLASS_TO_INDEX( F_C_NEG_INF,    2) +
	       CLASS_TO_INDEX( F_C_POS_NORM,   3) +
	       CLASS_TO_INDEX( F_C_NEG_NORM,   3) +
	       CLASS_TO_INDEX( F_C_POS_DENORM, 3) +
	       CLASS_TO_INDEX( F_C_NEG_DENORM, 3) +
	       CLASS_TO_INDEX( F_C_POS_ZERO,   4) +
	       CLASS_TO_INDEX( F_C_NEG_ZERO,   5) );

          /* index 2: mapping for x when y is +/- Inf */

#if defined(INTEL_CLASS_ACTION)
    PRINT_64_TBL_ITEM( CLASS_TO_ACTION_DISP(4) +
	      CLASS_TO_ACTION( F_C_SIG_NAN,    RETURN_QUIET_NAN,   1) +
              CLASS_TO_ACTION( F_C_QUIET_NAN,  RETURN_VALUE,       1) +
              CLASS_TO_ACTION( F_C_POS_INF,    RETURN_CPYSN_ARG_0, 2) +
              CLASS_TO_ACTION( F_C_NEG_INF,    RETURN_CPYSN_ARG_0, 3) +
              CLASS_TO_ACTION( F_C_POS_DENORM, RETURN_CPYSN_ARG_0, 4) +
              CLASS_TO_ACTION( F_C_NEG_DENORM, RETURN_CPYSN_ARG_0, 4) +
              CLASS_TO_ACTION( F_C_POS_NORM,   RETURN_CPYSN_ARG_0, 4) +
              CLASS_TO_ACTION( F_C_NEG_NORM,   RETURN_CPYSN_ARG_0, 4) +
              CLASS_TO_ACTION( F_C_POS_ZERO,   RETURN_CPYSN_ARG_0, 4) +
              CLASS_TO_ACTION( F_C_NEG_ZERO,   RETURN_CPYSN_ARG_0, 4) );
#else
    PRINT_64_TBL_ITEM( CLASS_TO_ACTION_DISP(4) +
	      CLASS_TO_ACTION( F_C_SIG_NAN,    RETURN_QUIET_NAN,   1) +
              CLASS_TO_ACTION( F_C_QUIET_NAN,  RETURN_VALUE,       1) +
              CLASS_TO_ACTION( F_C_POS_INF,    RETURN_ERROR,       2) +
              CLASS_TO_ACTION( F_C_NEG_INF,    RETURN_ERROR,       2) +
              CLASS_TO_ACTION( F_C_POS_DENORM, RETURN_CPYSN_ARG_0, 4) +
              CLASS_TO_ACTION( F_C_NEG_DENORM, RETURN_CPYSN_ARG_0, 4) +
              CLASS_TO_ACTION( F_C_POS_NORM,   RETURN_CPYSN_ARG_0, 4) +
              CLASS_TO_ACTION( F_C_NEG_NORM,   RETURN_CPYSN_ARG_0, 4) +
              CLASS_TO_ACTION( F_C_POS_ZERO,   RETURN_CPYSN_ARG_0, 4) +
              CLASS_TO_ACTION( F_C_NEG_ZERO,   RETURN_CPYSN_ARG_0, 4) );
#endif

          /* index 3: mapping for x when y is +/-Norm or +/-Denorm */

    PRINT_64_TBL_ITEM( CLASS_TO_ACTION_DISP(3) +
	      CLASS_TO_ACTION( F_C_SIG_NAN,    RETURN_QUIET_NAN,   1) +
              CLASS_TO_ACTION( F_C_QUIET_NAN,  RETURN_VALUE,       1) +
              CLASS_TO_ACTION( F_C_POS_INF,    RETURN_CPYSN_ARG_0, 5) +
              CLASS_TO_ACTION( F_C_NEG_INF,    RETURN_CPYSN_ARG_0, 6) +
              CLASS_TO_ACTION( F_C_POS_DENORM, RETURN_UNPACKED,    1) +
              CLASS_TO_ACTION( F_C_NEG_DENORM, RETURN_UNPACKED,    1) +
              CLASS_TO_ACTION( F_C_POS_NORM,   RETURN_UNPACKED,    1) +
              CLASS_TO_ACTION( F_C_NEG_NORM,   RETURN_UNPACKED,    1) +
              CLASS_TO_ACTION( F_C_POS_ZERO,   RETURN_CPYSN_ARG_0, 4) +
              CLASS_TO_ACTION( F_C_NEG_ZERO,   RETURN_CPYSN_ARG_0, 4) );

#if defined(INTEL_CLASS_ACTION)
          /* index 4: mapping for x when y is +Zero */

    PRINT_64_TBL_ITEM( CLASS_TO_ACTION_DISP(2) +
	      CLASS_TO_ACTION( F_C_SIG_NAN,    RETURN_QUIET_NAN,   1) +
              CLASS_TO_ACTION( F_C_QUIET_NAN,  RETURN_VALUE,       1) +
              CLASS_TO_ACTION( F_C_POS_INF,    RETURN_VALUE,       0) +
              CLASS_TO_ACTION( F_C_NEG_INF,    RETURN_CPYSN_ARG_0, 6) +
              CLASS_TO_ACTION( F_C_POS_DENORM, RETURN_VALUE,       0) +
              CLASS_TO_ACTION( F_C_NEG_DENORM, RETURN_CPYSN_ARG_0, 4) +
              CLASS_TO_ACTION( F_C_POS_NORM,   RETURN_VALUE,       0) +
              CLASS_TO_ACTION( F_C_NEG_NORM,   RETURN_CPYSN_ARG_0, 6) +
              CLASS_TO_ACTION( F_C_POS_ZERO,   RETURN_VALUE,       1) +
              CLASS_TO_ACTION( F_C_NEG_ZERO,   RETURN_VALUE,       6) );


          /* index 5: mapping for x when y is -Zero */
    PRINT_64_TBL_ITEM( CLASS_TO_ACTION_DISP(1) +
	      CLASS_TO_ACTION( F_C_SIG_NAN,    RETURN_QUIET_NAN,   1) +
              CLASS_TO_ACTION( F_C_QUIET_NAN,  RETURN_VALUE,       1) +
              CLASS_TO_ACTION( F_C_POS_INF,    RETURN_VALUE,       0) +
              CLASS_TO_ACTION( F_C_NEG_INF,    RETURN_CPYSN_ARG_0, 6) +
              CLASS_TO_ACTION( F_C_POS_DENORM, RETURN_VALUE,       0) +
              CLASS_TO_ACTION( F_C_NEG_DENORM, RETURN_CPYSN_ARG_0, 6) +
              CLASS_TO_ACTION( F_C_POS_NORM,   RETURN_VALUE,       0) +
              CLASS_TO_ACTION( F_C_NEG_NORM,   RETURN_CPYSN_ARG_0, 6) +
              CLASS_TO_ACTION( F_C_POS_ZERO,   RETURN_VALUE,       0) +
              CLASS_TO_ACTION( F_C_NEG_ZERO,   RETURN_CPYSN_ARG_0, 6) );
#else
          /* index 4: mapping for x when y is +Zero */

    PRINT_64_TBL_ITEM( CLASS_TO_ACTION_DISP(2) +
	      CLASS_TO_ACTION( F_C_SIG_NAN,    RETURN_QUIET_NAN,   1) +
              CLASS_TO_ACTION( F_C_QUIET_NAN,  RETURN_VALUE,       1) +
              CLASS_TO_ACTION( F_C_POS_INF,    RETURN_VALUE,       0) +
              CLASS_TO_ACTION( F_C_NEG_INF,    RETURN_CPYSN_ARG_0, 6) +
              CLASS_TO_ACTION( F_C_POS_DENORM, RETURN_VALUE,       0) +
              CLASS_TO_ACTION( F_C_NEG_DENORM, RETURN_CPYSN_ARG_0, 4) +
              CLASS_TO_ACTION( F_C_POS_NORM,   RETURN_VALUE,       0) +
              CLASS_TO_ACTION( F_C_NEG_NORM,   RETURN_CPYSN_ARG_0, 6) +
              CLASS_TO_ACTION( F_C_POS_ZERO,   RETURN_ERROR,       3) +
              CLASS_TO_ACTION( F_C_NEG_ZERO,   RETURN_ERROR,       3) );

          /* index 5: mapping for x when y is -Zero */
    PRINT_64_TBL_ITEM( CLASS_TO_ACTION_DISP(1) +
	      CLASS_TO_ACTION( F_C_SIG_NAN,    RETURN_QUIET_NAN,   1) +
              CLASS_TO_ACTION( F_C_QUIET_NAN,  RETURN_VALUE,       1) +
              CLASS_TO_ACTION( F_C_POS_INF,    RETURN_VALUE,       0) +
              CLASS_TO_ACTION( F_C_NEG_INF,    RETURN_CPYSN_ARG_0, 6) +
              CLASS_TO_ACTION( F_C_POS_DENORM, RETURN_VALUE,       0) +
              CLASS_TO_ACTION( F_C_NEG_DENORM, RETURN_CPYSN_ARG_0, 6) +
              CLASS_TO_ACTION( F_C_POS_NORM,   RETURN_VALUE,       0) +
              CLASS_TO_ACTION( F_C_NEG_NORM,   RETURN_CPYSN_ARG_0, 6) +
              CLASS_TO_ACTION( F_C_POS_ZERO,   RETURN_ERROR,       3) +
              CLASS_TO_ACTION( F_C_NEG_ZERO,   RETURN_ERROR,       3) );
#endif
	PRINT_U_TBL_ITEM( /* data 1 */            NULL );
#if defined(INTEL_CLASS_ACTION)
	PRINT_U_TBL_ITEM( /* data 2 */       PI_OVER_4 );
	PRINT_U_TBL_ITEM( /* data 3 */ THREE_PI_OVER_4 );
#else
	PRINT_U_TBL_ITEM( /* data 2 */  ATAN2_BOTH_INF );
	PRINT_U_TBL_ITEM( /* data 3 */ ATAN2_BOTH_ZERO );
#endif
	PRINT_U_TBL_ITEM( /* data 4 */       PI_OVER_2 );
	PRINT_U_TBL_ITEM( /* data 5 */            ZERO );
	PRINT_U_TBL_ITEM( /* data 6 */              PI );


    TABLE_COMMENT("atan2d(y,x) class-to-action-mapping");
    PRINT_CLASS_TO_ACTION_TBL_DEF( "ATAND2_CLASS_TO_ACTION_MAP");

	  /* Index 0: class-to-action for y */

    PRINT_64_TBL_ITEM( CLASS_TO_ACTION_DISP(7) +
	      CLASS_TO_ACTION( F_C_SIG_NAN,    RETURN_QUIET_NAN, 0) +
              CLASS_TO_ACTION( F_C_QUIET_NAN,  RETURN_VALUE,     0) );

	   /* Index 1: class-to-index mapping */

    PRINT_64_TBL_ITEM( 
	       CLASS_TO_INDEX( F_C_POS_INF,    2) +
	       CLASS_TO_INDEX( F_C_NEG_INF,    3) +
	       CLASS_TO_INDEX( F_C_POS_NORM,   4) +
	       CLASS_TO_INDEX( F_C_NEG_NORM,   5) +
	       CLASS_TO_INDEX( F_C_POS_DENORM, 4) +
	       CLASS_TO_INDEX( F_C_NEG_DENORM, 5) +
	       CLASS_TO_INDEX( F_C_POS_ZERO,   6) +
	       CLASS_TO_INDEX( F_C_NEG_ZERO,   7) );

          /* index 2: mapping for x when y is +Inf */

    PRINT_64_TBL_ITEM( CLASS_TO_ACTION_DISP(6) +
	      CLASS_TO_ACTION( F_C_SIG_NAN,    RETURN_QUIET_NAN, 1) +
              CLASS_TO_ACTION( F_C_QUIET_NAN,  RETURN_VALUE,     1) +
              CLASS_TO_ACTION( F_C_POS_INF,    RETURN_ERROR,     2) +
              CLASS_TO_ACTION( F_C_NEG_INF,    RETURN_ERROR,     2) +
              CLASS_TO_ACTION( F_C_POS_DENORM, RETURN_VALUE,     4) +
              CLASS_TO_ACTION( F_C_NEG_DENORM, RETURN_VALUE,     4) +
              CLASS_TO_ACTION( F_C_POS_NORM,   RETURN_VALUE,     4) +
              CLASS_TO_ACTION( F_C_NEG_NORM,   RETURN_VALUE,     4) +
              CLASS_TO_ACTION( F_C_POS_ZERO,   RETURN_VALUE,     4) +
              CLASS_TO_ACTION( F_C_NEG_ZERO,   RETURN_VALUE,     4) );

          /* index 3: mapping for x when y is -Inf */

    PRINT_64_TBL_ITEM( CLASS_TO_ACTION_DISP(5) +
	      CLASS_TO_ACTION( F_C_SIG_NAN,    RETURN_QUIET_NAN, 1) +
              CLASS_TO_ACTION( F_C_QUIET_NAN,  RETURN_VALUE,     1) +
              CLASS_TO_ACTION( F_C_POS_INF,    RETURN_ERROR,     2) +
              CLASS_TO_ACTION( F_C_NEG_INF,    RETURN_ERROR,     2) +
              CLASS_TO_ACTION( F_C_POS_DENORM, RETURN_NEGATIVE,  4) +
              CLASS_TO_ACTION( F_C_NEG_DENORM, RETURN_NEGATIVE,  4) +
              CLASS_TO_ACTION( F_C_POS_NORM,   RETURN_NEGATIVE,  4) +
              CLASS_TO_ACTION( F_C_NEG_NORM,   RETURN_NEGATIVE,  4) +
              CLASS_TO_ACTION( F_C_POS_ZERO,   RETURN_NEGATIVE,  4) +
              CLASS_TO_ACTION( F_C_NEG_ZERO,   RETURN_NEGATIVE,  4) );

          /* index 4: mapping for x when y is +Norm or +Denorm */

    PRINT_64_TBL_ITEM( CLASS_TO_ACTION_DISP(4) +
	      CLASS_TO_ACTION( F_C_SIG_NAN,    RETURN_QUIET_NAN, 1) +
              CLASS_TO_ACTION( F_C_QUIET_NAN,  RETURN_VALUE,     1) +
              CLASS_TO_ACTION( F_C_POS_INF,    RETURN_VALUE,     5) +
              CLASS_TO_ACTION( F_C_NEG_INF,    RETURN_VALUE,     6) +
              CLASS_TO_ACTION( F_C_POS_DENORM, RETURN_UNPACKED,  1) +
              CLASS_TO_ACTION( F_C_NEG_DENORM, RETURN_UNPACKED,  1) +
              CLASS_TO_ACTION( F_C_POS_NORM,   RETURN_UNPACKED,  1) +
              CLASS_TO_ACTION( F_C_NEG_NORM,   RETURN_UNPACKED,  1) +
              CLASS_TO_ACTION( F_C_POS_ZERO,   RETURN_VALUE,     4) +
              CLASS_TO_ACTION( F_C_NEG_ZERO,   RETURN_VALUE,     4) );

          /* index 5: mapping for x when y is -Norm or -Denorm */

    PRINT_64_TBL_ITEM( CLASS_TO_ACTION_DISP(3) +
	      CLASS_TO_ACTION( F_C_SIG_NAN,    RETURN_QUIET_NAN, 1) +
              CLASS_TO_ACTION( F_C_QUIET_NAN,  RETURN_VALUE,     1) +
              CLASS_TO_ACTION( F_C_POS_INF,    RETURN_NEGATIVE,  5) +
              CLASS_TO_ACTION( F_C_NEG_INF,    RETURN_NEGATIVE,  6) +
              CLASS_TO_ACTION( F_C_POS_DENORM, RETURN_UNPACKED,  1) +
              CLASS_TO_ACTION( F_C_NEG_DENORM, RETURN_UNPACKED,  1) +
              CLASS_TO_ACTION( F_C_POS_NORM,   RETURN_UNPACKED,  1) +
              CLASS_TO_ACTION( F_C_NEG_NORM,   RETURN_UNPACKED,  1) +
              CLASS_TO_ACTION( F_C_POS_ZERO,   RETURN_NEGATIVE,  4) +
              CLASS_TO_ACTION( F_C_NEG_ZERO,   RETURN_NEGATIVE,  4) );

          /* index 6: mapping for x when y is +Zero */

    PRINT_64_TBL_ITEM( CLASS_TO_ACTION_DISP(2) +
	      CLASS_TO_ACTION( F_C_SIG_NAN,    RETURN_QUIET_NAN, 1) +
              CLASS_TO_ACTION( F_C_QUIET_NAN,  RETURN_VALUE,     1) +
              CLASS_TO_ACTION( F_C_POS_INF,    RETURN_VALUE,     0) +
              CLASS_TO_ACTION( F_C_NEG_INF,    RETURN_VALUE,     6) +
              CLASS_TO_ACTION( F_C_POS_DENORM, RETURN_VALUE,     0) +
              CLASS_TO_ACTION( F_C_NEG_DENORM, RETURN_VALUE,     4) +
              CLASS_TO_ACTION( F_C_POS_NORM,   RETURN_VALUE,     0) +
              CLASS_TO_ACTION( F_C_NEG_NORM,   RETURN_VALUE,     6) +
              CLASS_TO_ACTION( F_C_POS_ZERO,   RETURN_ERROR,     3) +
              CLASS_TO_ACTION( F_C_NEG_ZERO,   RETURN_ERROR,     3) );

          /* index 7: mapping for x when y is -Zero */

#if defined(INTEL_CLASS_ACTION)

    PRINT_64_TBL_ITEM( CLASS_TO_ACTION_DISP(1) +
	      CLASS_TO_ACTION( F_C_SIG_NAN,    RETURN_QUIET_NAN, 1) +
              CLASS_TO_ACTION( F_C_QUIET_NAN,  RETURN_VALUE,     1) +
              CLASS_TO_ACTION( F_C_POS_INF,    RETURN_VALUE,     0) +
              CLASS_TO_ACTION( F_C_NEG_INF,    RETURN_NEGATIVE,  6) +
              CLASS_TO_ACTION( F_C_POS_DENORM, RETURN_VALUE,     0) +
              CLASS_TO_ACTION( F_C_NEG_DENORM, RETURN_NEGATIVE,  6) +
              CLASS_TO_ACTION( F_C_POS_NORM,   RETURN_VALUE,     0) +
              CLASS_TO_ACTION( F_C_NEG_NORM,   RETURN_NEGATIVE,  6) +
              CLASS_TO_ACTION( F_C_POS_ZERO,   RETURN_ERROR,     3) +
              CLASS_TO_ACTION( F_C_NEG_ZERO,   RETURN_NEGATIVE,  6) );
#else

    PRINT_64_TBL_ITEM( CLASS_TO_ACTION_DISP(1) +
	      CLASS_TO_ACTION( F_C_SIG_NAN,    RETURN_QUIET_NAN, 1) +
              CLASS_TO_ACTION( F_C_QUIET_NAN,  RETURN_VALUE,     1) +
              CLASS_TO_ACTION( F_C_POS_INF,    RETURN_VALUE,     0) +
              CLASS_TO_ACTION( F_C_NEG_INF,    RETURN_NEGATIVE,  6) +
              CLASS_TO_ACTION( F_C_POS_DENORM, RETURN_VALUE,     0) +
              CLASS_TO_ACTION( F_C_NEG_DENORM, RETURN_NEGATIVE,  6) +
              CLASS_TO_ACTION( F_C_POS_NORM,   RETURN_VALUE,     0) +
              CLASS_TO_ACTION( F_C_NEG_NORM,   RETURN_NEGATIVE,  6) +
              CLASS_TO_ACTION( F_C_POS_ZERO,   RETURN_ERROR,     3) +
              CLASS_TO_ACTION( F_C_NEG_ZERO,   RETURN_ERROR,     3 ) );
#endif

	PRINT_U_TBL_ITEM( /* data 1 */             NULL );
	PRINT_U_TBL_ITEM( /* data 2 */  ATAND2_BOTH_INF );
	PRINT_U_TBL_ITEM( /* data 3 */ ATAND2_BOTH_ZERO );
	PRINT_U_TBL_ITEM( /* data 4 */           NINETY );
	PRINT_U_TBL_ITEM( /* data 5 */             ZERO );
	PRINT_U_TBL_ITEM( /* data 6 */       ONE_EIGHTY );

    /*
    ** The following code generates the "table" of constants that the
    ** UX_ATAN2 and UX_ASIN_ACOS routines index into find the appropriate
    ** additive term.  As each value is added to the table, its offset
    ** (in bytes) is computed and recorded as a #define.
    */

    TABLE_COMMENT("0, pi/4, pi/2, 3pi/4, pi in unpacked format");
    PRINT_UX_TBL_ADEF("INV_TRIG_CONS_BASE\t");
    inv_trig_cons_base = MP_BIT_OFFSET;

#   define PRINT_BYTE_OFFSET(name)			\
		printf("#define " name "\t%i\n",	\
		   BYTES(MP_BIT_OFFSET - inv_trig_cons_base))

    PRINT_UX_TBL_ADEF("UX_ZERO\t\t\t\t" );
    PRINT_BYTE_OFFSET( "UX_ZERO_INDEX\t\t" );         PRINT_UX_TBL_ITEM(0);
    PRINT_BYTE_OFFSET( "UX_PI_OVER_4_INDEX\t" );      PRINT_UX_TBL_ITEM(pi/4);
    PRINT_BYTE_OFFSET( "UX_PI_OVER_2_INDEX\t" );      PRINT_UX_TBL_ITEM(pi/2);
    PRINT_BYTE_OFFSET( "UX_THREE_QUARTERS_PI_INDEX"); PRINT_UX_TBL_ITEM(3*pi/4);
    PRINT_BYTE_OFFSET( "UX_PI_INDEX\t\t" );           PRINT_UX_TBL_ITEM(pi);

    /* Miscellaneous constants */

    TABLE_COMMENT("1, 180/pi, 1/3 in unpacked format");
    PRINT_UX_TBL_ADEF_ITEM("UX_ONE\t\t\t", 1);
    PRINT_UX_TBL_ADEF_ITEM("UX_RAD_TO_DEG\t\t", 180/pi );
    PRINT_UX_TBL_ADEF_ITEM("UX_ONE_THIRD\t\t", 1/3 );

    /*
    ** Get the rational coefficients for atan.  Since the reduced argument
    ** is always less that 1/2, we can scale the argument up by 2, which
    ** puts more leading zeros in the coefficients and there by promotes
    ** early exits from the polynomial loop
    */

    function __atan(z)
        {
        auto x;

        x = .5*z;
        if (x == 0)
            return 1.;
        else
            return atan(x)/x;
        }

    save_precision = precision;
    precision = ceil(2*UX_PRECISION/8);

    max_arg = 2*(1/2);

    remes(REMES_FIND_RATIONAL + REMES_RELATIVE_WEIGHT + REMES_SQUARE_ARG,
       0, max_arg, __atan, UX_PRECISION, &num_degree, &den_degree,
       &ux_rational_coefs);
    precision = save_precision;

    TABLE_COMMENT("Fixed point coefficients for atan evaluation");
    PRINT_FIXED_128_TBL_ADEF("ATAN_COEF_ARRAY\t\t");
    degree = print_ux_rational_coefs(num_degree, den_degree, -1);
    PRINT_WORD_DEF("ATAN_COEF_ARRAY_DEGREE\t", degree );

    /* One more time for asin rational coefficients.  Again, we scale by 2 */

    function __asin(z)
        {
        auto x;

        x = .5*z;
        if (x == 0)
            return 1.;
        else
            return asin(x)/x;
        }

    save_precision = precision;
    precision = ceil(2*UX_PRECISION/8);

    max_arg = 2*(1/2);

    remes(REMES_FIND_RATIONAL + REMES_RELATIVE_WEIGHT + REMES_SQUARE_ARG,
       0, max_arg, __asin, UX_PRECISION, &num_degree, &den_degree,
       &ux_rational_coefs);
    precision = save_precision;

    TABLE_COMMENT("Fixed point coefficients for asin evaluation");
    PRINT_FIXED_128_TBL_ADEF("ASIN_COEF_ARRAY\t\t");
    degree = print_ux_rational_coefs(num_degree, den_degree, -1);
    PRINT_WORD_DEF("ASIN_COEF_ARRAY_DEGREE\t", degree );

    END_TABLE;

    @end_divert
    @eval my $tableText;						\
          my $outText    = MphocEval( GetStream( "divertText" ) );	\
          my $defineText = Egrep( "#define", $outText, \$tableText );	\
             $outText    = "$tableText\n\n$defineText";			\
          my $headerText = GetHeaderText( STR(BUILD_FILE_NAME),         \
                           "Definitions and constants inverse " . 	\
                              "trigonomic routines", __FILE__ );	\
             print "$headerText\n\n$outText\n";

#endif
