xref: /src/lib/libc/arch/m68k/softfloat/softfloat.h

/*	$NetBSD: softfloat.h,v 1.11 2025/09/17 11:37:38 nat Exp $	*/

/* This is a derivative work. */

/*
===============================================================================

This C header file is part of the SoftFloat IEC/IEEE Floating-point
Arithmetic Package, Release 2a.

Written by John R. Hauser.  This work was made possible in part by the
International Computer Science Institute, located at Suite 600, 1947 Center
Street, Berkeley, California 94704.  Funding was partially provided by the
National Science Foundation under grant MIP-9311980.  The original version
of this code was written as part of a project to build a fixed-point vector
processor in collaboration with the University of California at Berkeley,
overseen by Profs. Nelson Morgan and John Wawrzynek.  More information
is available through the Web page `http://HTTP.CS.Berkeley.EDU/~jhauser/
arithmetic/SoftFloat.html'.

THIS SOFTWARE IS DISTRIBUTED AS IS, FOR FREE.  Although reasonable effort
has been made to avoid it, THIS SOFTWARE MAY CONTAIN FAULTS THAT WILL AT
TIMES RESULT IN INCORRECT BEHAVIOR.  USE OF THIS SOFTWARE IS RESTRICTED TO
PERSONS AND ORGANIZATIONS WHO CAN AND WILL TAKE FULL RESPONSIBILITY FOR ANY
AND ALL LOSSES, COSTS, OR OTHER PROBLEMS ARISING FROM ITS USE.

Derivative works are acceptable, even for commercial purposes, so long as
(1) they include prominent notice that the work is derivative, and (2) they
include prominent notice akin to these four paragraphs for those parts of
this code that are retained.

===============================================================================
*/

/*
-------------------------------------------------------------------------------
The macro `FLOATX80' must be defined to enable the extended double-precision
floating-point format `floatx80'.  If this macro is not defined, the
`floatx80' type will not be defined, and none of the functions that either
input or output the `floatx80' type will be defined.  The same applies to
the `FLOAT128' macro and the quadruple-precision format `float128'.
-------------------------------------------------------------------------------
*/
#ifndef __mcoldfire__
#define FLOATX80
#endif
/* #define FLOAT128 */

#include <machine/ieeefp.h>

/*
-------------------------------------------------------------------------------
Software IEC/IEEE floating-point types.
-------------------------------------------------------------------------------
*/
typedef unsigned int float32;
typedef unsigned long long float64;
#ifdef FLOATX80
#define X80SHIFT	16

typedef struct {
    unsigned long high;
    unsigned long long low;
}__packed floatx80;
#endif
#ifdef FLOAT128
typedef struct {
    unsigned long long high, low;
} float128;
#endif

/*
-------------------------------------------------------------------------------
Software IEC/IEEE floating-point underflow tininess-detection mode.
-------------------------------------------------------------------------------
*/
#ifndef SOFTFLOAT_FOR_GCC
extern int8 float_detect_tininess;
#endif
enum {
    float_tininess_after_rounding  = 0,
    float_tininess_before_rounding = 1
};

/*
-------------------------------------------------------------------------------
Software IEC/IEEE floating-point rounding mode.
-------------------------------------------------------------------------------
*/
extern fp_rnd float_rounding_mode;
#define float_round_nearest_even FP_RN
#define float_round_to_zero      FP_RZ
#define float_round_down         FP_RM
#define float_round_up           FP_RP

/*
-------------------------------------------------------------------------------
Software IEC/IEEE floating-point exception flags.
-------------------------------------------------------------------------------
*/
extern fp_except float_exception_flags;
extern fp_except float_exception_mask;
enum {
    float_flag_inexact   = FP_X_IMP,
    float_flag_underflow = FP_X_UFL,
    float_flag_overflow  = FP_X_OFL,
    float_flag_divbyzero = FP_X_DZ,
    float_flag_invalid   = FP_X_INV
};

/*
-------------------------------------------------------------------------------
Routine to raise any or all of the software IEC/IEEE floating-point
exception flags.
-------------------------------------------------------------------------------
*/
void float_raise( fp_except );

/*
-------------------------------------------------------------------------------
Software IEC/IEEE integer-to-floating-point conversion routines.
-------------------------------------------------------------------------------
*/
float32 int32_to_float32( int32 );
float32 uint32_to_float32( uint32 );
float64 int32_to_float64( int32 );
float64 uint32_to_float64( uint32 );
#ifdef FLOATX80
floatx80 int32_to_floatx80( int32 );
floatx80 uint32_to_floatx80( uint32 );
#endif
#ifdef FLOAT128
float128 int32_to_float128( int32 );
float128 uint32_to_float128( uint32 );
#endif
float32 int64_to_float32( long long );
float64 int64_to_float64( long long );
#ifdef FLOATX80
floatx80 int64_to_floatx80( long long );
#endif
#ifdef FLOAT128
float128 int64_to_float128( long long );
#endif

/*
-------------------------------------------------------------------------------
Software IEC/IEEE single-precision conversion routines.
-------------------------------------------------------------------------------
*/
int float32_to_int32( float32 );
int float32_to_int32_round_to_zero( float32 );
unsigned int float32_to_uint32_round_to_zero( float32 );
long long float32_to_int64( float32 );
long long float32_to_int64_round_to_zero( float32 );
float64 float32_to_float64( float32 );
#ifdef FLOATX80
floatx80 float32_to_floatx80( float32 );
#endif
#ifdef FLOAT128
float128 float32_to_float128( float32 );
#endif

/*
-------------------------------------------------------------------------------
Software IEC/IEEE single-precision operations.
-------------------------------------------------------------------------------
*/
float32 float32_round_to_int( float32 );
float32 float32_add( float32, float32 );
float32 float32_sub( float32, float32 );
float32 float32_mul( float32, float32 );
float32 float32_div( float32, float32 );
float32 float32_rem( float32, float32 );
float32 float32_sqrt( float32 );
flag float32_eq( float32, float32 );
flag float32_le( float32, float32 );
flag float32_lt( float32, float32 );
flag float32_eq_signaling( float32, float32 );
flag float32_le_quiet( float32, float32 );
flag float32_lt_quiet( float32, float32 );
#if !defined(SOFTFLOAT_FOR_GCC) || defined(SOFTFLOATM68K_FOR_GCC)
flag float32_is_signaling_nan( float32 );
#endif

/*
-------------------------------------------------------------------------------
Software IEC/IEEE double-precision conversion routines.
-------------------------------------------------------------------------------
*/
int float64_to_int32( float64 );
int float64_to_int32_round_to_zero( float64 );
unsigned int float64_to_uint32_round_to_zero( float64 );
long long float64_to_int64( float64 );
long long float64_to_int64_round_to_zero( float64 );
float32 float64_to_float32( float64 );
#ifdef FLOATX80
floatx80 float64_to_floatx80( float64 );
#endif
#ifdef FLOAT128
float128 float64_to_float128( float64 );
#endif

/*
-------------------------------------------------------------------------------
Software IEC/IEEE double-precision operations.
-------------------------------------------------------------------------------
*/
float64 float64_round_to_int( float64 );
float64 float64_add( float64, float64 );
float64 float64_sub( float64, float64 );
float64 float64_mul( float64, float64 );
float64 float64_div( float64, float64 );
float64 float64_rem( float64, float64 );
float64 float64_sqrt( float64 );
flag float64_eq( float64, float64 );
flag float64_le( float64, float64 );
flag float64_lt( float64, float64 );
flag float64_eq_signaling( float64, float64 );
flag float64_le_quiet( float64, float64 );
flag float64_lt_quiet( float64, float64 );
#if !defined(SOFTFLOAT_FOR_GCC) || defined(SOFTFLOATM68K_FOR_GCC)
flag float64_is_signaling_nan( float64 );
#endif

#ifdef FLOATX80

/*
-------------------------------------------------------------------------------
Software IEC/IEEE extended double-precision conversion routines.
-------------------------------------------------------------------------------
*/
int floatx80_to_int32( floatx80 );
int floatx80_to_int32_round_to_zero( floatx80 );
long long floatx80_to_int64( floatx80 );
long long floatx80_to_int64_round_to_zero( floatx80 );
float32 floatx80_to_float32( floatx80 );
float64 floatx80_to_float64( floatx80 );
#ifdef FLOAT128
float128 floatx80_to_float128( floatx80 );
#endif

/*
-------------------------------------------------------------------------------
Software IEC/IEEE extended double-precision rounding precision.  Valid
values are 32, 64, and 80.
-------------------------------------------------------------------------------
*/
extern int floatx80_rounding_precision;

/*
-------------------------------------------------------------------------------
Software IEC/IEEE extended double-precision operations.
-------------------------------------------------------------------------------
*/
floatx80 floatx80_round_to_int( floatx80 );
floatx80 floatx80_add( floatx80, floatx80 );
floatx80 floatx80_sub( floatx80, floatx80 );
floatx80 floatx80_mul( floatx80, floatx80 );
floatx80 floatx80_div( floatx80, floatx80 );
floatx80 floatx80_rem( floatx80, floatx80 );
floatx80 floatx80_sqrt( floatx80 );
flag floatx80_eq( floatx80, floatx80 );
flag floatx80_le( floatx80, floatx80 );
flag floatx80_lt( floatx80, floatx80 );
flag floatx80_eq_signaling( floatx80, floatx80 );
flag floatx80_le_quiet( floatx80, floatx80 );
flag floatx80_lt_quiet( floatx80, floatx80 );
flag floatx80_is_signaling_nan( floatx80 );
flag floatx80_is_nan( floatx80 );

#endif

#ifdef FLOAT128

/*
-------------------------------------------------------------------------------
Software IEC/IEEE quadruple-precision conversion routines.
-------------------------------------------------------------------------------
*/
int float128_to_int32( float128 );
int float128_to_int32_round_to_zero( float128 );
long long float128_to_int64( float128 );
long long float128_to_int64_round_to_zero( float128 );
float32 float128_to_float32( float128 );
float64 float128_to_float64( float128 );
#ifdef FLOATX80
floatx80 float128_to_floatx80( float128 );
#endif

/*
-------------------------------------------------------------------------------
Software IEC/IEEE quadruple-precision operations.
-------------------------------------------------------------------------------
*/
float128 float128_round_to_int( float128 );
float128 float128_add( float128, float128 );
float128 float128_sub( float128, float128 );
float128 float128_mul( float128, float128 );
float128 float128_div( float128, float128 );
float128 float128_rem( float128, float128 );
float128 float128_sqrt( float128 );
flag float128_eq( float128, float128 );
flag float128_le( float128, float128 );
flag float128_lt( float128, float128 );
flag float128_eq_signaling( float128, float128 );
flag float128_le_quiet( float128, float128 );
flag float128_lt_quiet( float128, float128 );
flag float128_is_signaling_nan( float128 );

#endif