/******************************************************************************
 *
 * Copyright (c) 1996-2002 PalmSource, Inc. All rights reserved.
 *
 * File: FloatMgr.h
 *
 * Release: Palm OS 5 SDK (68K) R2.
 *
 * Description:
 *		New Floating point routines, provided by new IEEE arithmetic
 *		68K software floating point emulator (sfpe) code.
 *
 *****************************************************************************/

#ifndef __FLOATMGR_H__
#define __FLOATMGR_H__

#if defined(__MC68K__)
#if __option(IEEEdoubles) == off
//#error "IEEEdoubles ('8-UInt8 Doubles' option in the 68K Processor preference panel) MUST be on!!"
#pragma IEEEdoubles on		// force 8-byte doubles for our initialization!!
#endif
#endif


#ifndef _DONT_USE_FP_TRAPS_
#if EMULATION_LEVEL != EMULATION_NONE 
#define _DONT_USE_FP_TRAPS_	1		// always direct link to FP for emulator builds
#endif
#endif


#include <PalmTypes.h>
#include <CoreTraps.h>

/************************************************************************
 * Differences between FloatMgr (PalmOS v1.0) and (this) NewFloatMgr
 ***********************************************************************/
//
// FloatMgr (PalmOS v1.0)		NewFloatMgr
// ----------------------		---------------------------------------------
// FloatType (64-bits)			use FlpFloat (32-bits) or FlpDouble (64-bits)
//
// fplErrOutOfRange				use _fp_get_fpscr() to retrieve errors 
//
// FplInit()						not necessary
// FplFree()						not necessary
//
// FplFToA()						use FlpFToA()
// FplAToF()						use FlpAToF()
// FplBase10Info()				use FlpBase10Info() [*signP returns sign BIT: 1 if negative]
//
// FplLongToFloat()				use _f_itof() or _d_itod()
// FplFloatToLong()				use _f_ftoi() or _d_dtoi()
// FplFloatToULong()				use _f_ftou() or _d_dtou()
//
// FplMul()							use _f_mul() or _d_mul()
// FplAdd()							use _f_add() or _d_add()
// FplSub()							use _f_sub() or _d_sub()
// FplDiv()							use _f_div() or _d_div()



/************************************************************************
 * New Floating point manager constants
 ***********************************************************************/

#define flpVersion		0x02008000	// first version of NewFloatMgr (PalmOS 2.0)

/*
 * These constants are passed to and received from the _fp_round routine.
 */

#define flpToNearest		0
#define flpTowardZero	1
#define flpUpward			3
#define flpDownward		2
#define flpModeMask		0x00000030
#define flpModeShift		4

/*
 * These masks define the fpscr bits supported by the sfpe (software floating point emulator).
 * These constants are used with the _fp_get_fpscr and _fp_set_fpscr routines.
 */

#define flpInvalid		0x00008000
#define flpOverflow		0x00004000
#define flpUnderflow		0x00002000
#define flpDivByZero		0x00001000
#define flpInexact		0x00000800

/*
 * These constants are returned by _d_cmp, _d_cmpe, _f_cmp, and _f_cmpe:
 */

#define flpEqual			0
#define flpLess			1
#define flpGreater		2
#define flpUnordered		3


/************************************************************************
 * New Floating point manager types (private)
 ***********************************************************************/
typedef struct {
	Int32 high;
	Int32 low;
} _sfpe_64_bits;											// for internal use only

typedef _sfpe_64_bits sfpe_long_long;				// for internal use only
typedef _sfpe_64_bits sfpe_unsigned_long_long;	// for internal use only


/************************************************************************
 * New Floating point manager types (public)
 ***********************************************************************/
typedef Int32 FlpFloat;
typedef _sfpe_64_bits FlpDouble;
typedef _sfpe_64_bits FlpLongDouble;

/*
* A double value comprises the fields:
*		0x80000000 0x00000000 -- sign bit (1 for negative)
*		0x7ff00000 0x00000000 -- exponent, biased by 0x3ff == 1023
*		0x000fffff 0xffffffff -- significand == the fraction after an implicit "1."
* So a double has the mathematical form:
*		(-1)^sign_bit * 2^(exponent - bias) * 1.significand
* What follows are some structures (and macros) useful for decomposing numbers.
*/

typedef struct {
	UInt32	sign : 1;
	Int32		exp  : 11;
	UInt32	manH : 20;
	UInt32	manL;
} FlpDoubleBits;						// for accessing specific fields

typedef union {
        double				d;			// for easy assignment of values
        FlpDouble			fd;		// for calling New Floating point manager routines
        UInt32				ul[2];	// for accessing upper and lower longs
        FlpDoubleBits	fdb;		// for accessing specific fields
} FlpCompDouble;

typedef union {
        float				f;			// for easy assignment of values
        FlpFloat			ff;		// for calling New Floating point manager routines
        UInt32				ul;		// for accessing bits of the float
} FlpCompFloat;


/************************************************************************
 * Useful macros...
 ***********************************************************************/
#define BIG_ENDIAN 1
#define __FIRST32(x) *((UInt32 *) &x)
#define __SECOND32(x) *((UInt32 *) &x + 1)
#define __ALL32(x) *((UInt32 *) &x)

#ifdef LITTLE_ENDIAN
#define __LO32(x) *((UInt32 *) &x)
#define __HI32(x) *((UInt32 *) &x + 1)
#define __HIX 1
#define __LOX 0
#else
#define __HI32(x) *((UInt32 *) &x)
#define __LO32(x) *((UInt32 *) &x + 1)
#define __HIX 0
#define __LOX 1
#endif

#define FlpGetSign(x)			((__HI32(x) & 0x80000000) != 0)
#define FlpIsZero(x)				( ((__HI32(x) & 0x7fffffff) | (__LO32(x))) == 0)

#define FlpGetExponent(x)		(((__HI32(x) & 0x7ff00000) >> 20) - 1023)


#define FlpNegate(x)				(((FlpCompDouble *)&x)->ul[__HIX] ^= 0x80000000)
#define FlpSetNegative(x)		(((FlpCompDouble *)&x)->ul[__HIX] |= 0x80000000)
#define FlpSetPositive(x)		(((FlpCompDouble *)&x)->ul[__HIX] &= ~0x80000000)
	
	
/*******************************************************************
 * New Floating point manager errors
 * The constant fplErrorClass is defined in SystemMgr.h
 *******************************************************************/
#define	flpErrOutOfRange			(flpErrorClass | 1)

	
/************************************************************
 * New Floating point manager trap macros
 *************************************************************/

#if _DONT_USE_FP_TRAPS_

#define FLOAT_TRAP(floatSelectorNum)
#define FLOAT_EM_TRAP(floatSelectorNum)

#else

#define FLOAT_TRAP(sel) \
	_SYSTEM_API(_CALL_WITH_SELECTOR)(_SYSTEM_TABLE, sysTrapFlpDispatch, sel)

#define FLOAT_EM_TRAP(sel) \
	_SYSTEM_API(_CALL_WITH_SELECTOR)(_SYSTEM_TABLE, sysTrapFlpEmDispatch, sel)

#endif

/************************************************************
 * New Floating point manager selectors
 *************************************************************/

// The order of these #defines *MUST* match the
// corresponding table in NewFloatDispatch.c
#define sysFloatBase10Info			0
#define sysFloatFToA					1
#define sysFloatAToF					2
#define sysFloatCorrectedAdd		3
#define sysFloatCorrectedSub		4
#define sysFloatVersion				5

// used by NewFloatDispatch.c
#define flpMaxFloatSelector		sysFloatVersion


// The order of these #defines *MUST* match the
// corresponding table in NewFloatDispatch.c
#define sysFloatEm_fp_round		0
#define sysFloatEm_fp_get_fpscr	1
#define sysFloatEm_fp_set_fpscr	2

#define sysFloatEm_f_utof			3
#define sysFloatEm_f_itof			4
#define sysFloatEm_f_ulltof		5
#define sysFloatEm_f_lltof			6

#define sysFloatEm_d_utod			7
#define sysFloatEm_d_itod			8
#define sysFloatEm_d_ulltod		9
#define sysFloatEm_d_lltod			10

#define sysFloatEm_f_ftod			11
#define sysFloatEm_d_dtof			12
#define sysFloatEm_f_ftoq			13
#define sysFloatEm_f_qtof			14
#define sysFloatEm_d_dtoq			15
#define sysFloatEm_d_qtod			16

#define sysFloatEm_f_ftou			17
#define sysFloatEm_f_ftoi			18
#define sysFloatEm_f_ftoull		19
#define sysFloatEm_f_ftoll			20

#define sysFloatEm_d_dtou			21
#define sysFloatEm_d_dtoi			22
#define sysFloatEm_d_dtoull		23
#define sysFloatEm_d_dtoll			24

#define sysFloatEm_f_cmp			25
#define sysFloatEm_f_cmpe			26
#define sysFloatEm_f_feq			27
#define sysFloatEm_f_fne			28
#define sysFloatEm_f_flt			29
#define sysFloatEm_f_fle			30
#define sysFloatEm_f_fgt			31
#define sysFloatEm_f_fge			32
#define sysFloatEm_f_fun			33
#define sysFloatEm_f_for			34

#define sysFloatEm_d_cmp			35
#define sysFloatEm_d_cmpe			36
#define sysFloatEm_d_feq			37
#define sysFloatEm_d_fne			38
#define sysFloatEm_d_flt			39
#define sysFloatEm_d_fle			40
#define sysFloatEm_d_fgt			41
#define sysFloatEm_d_fge			42
#define sysFloatEm_d_fun			43
#define sysFloatEm_d_for			44

#define sysFloatEm_f_neg			45
#define sysFloatEm_f_add			46
#define sysFloatEm_f_mul			47
#define sysFloatEm_f_sub			48
#define sysFloatEm_f_div			49

#define sysFloatEm_d_neg			50
#define sysFloatEm_d_add			51
#define sysFloatEm_d_mul			52
#define sysFloatEm_d_sub			53
#define sysFloatEm_d_div			54


#ifdef __cplusplus
extern "C" {
#endif

/************************************************************
 * New Floating point manager routines
 *************************************************************/

				// Note: FlpBase10Info returns the actual sign bit in *signP (1 if negative)
				// Note: FlpBase10Info reports that zero is "negative".
				//			A workaround is to check (*signP && *mantissaP) instead of just *signP.
Err 			FlpBase10Info(FlpDouble a, UInt32 *mantissaP, Int16 *exponentP, Int16 *signP)
					FLOAT_TRAP(sysFloatBase10Info);

Err 			FlpFToA(FlpDouble a, Char *s)
					FLOAT_TRAP(sysFloatFToA);

FlpDouble	FlpAToF(const Char *s)
					FLOAT_TRAP(sysFloatAToF);

FlpDouble	FlpCorrectedAdd(FlpDouble firstOperand, FlpDouble secondOperand, Int16 howAccurate)
					FLOAT_TRAP(sysFloatCorrectedAdd);

FlpDouble	FlpCorrectedSub(FlpDouble firstOperand, FlpDouble secondOperand, Int16 howAccurate)
					FLOAT_TRAP(sysFloatCorrectedSub);

#if EMULATION_LEVEL == EMULATION_NONE

// These next three functions correspond to the previous three above.
// The signatures are different, but in fact with CodeWarrior for Palm OS
// the structure return values above are implemented via a hidden pointer
// parameter, so corresponding functions are binary compatible.  Programs
// using CodeWarrior to target m68k Palm OS can use either function
// interchangeably.
//
// However, a description of the handling of structure return values is
// missing from the defined Palm OS ABI, and m68k-palmos-gcc does it
// differently.  So programs compiled with GCC using the standard functions
// above are likely to crash: GCC users must use the FlpBuffer* forms of
// these functions.
//
// The FlpBuffer* functions are not available on the Simulator, so you need
// to use the standard versions above if you want Simulator compatibility.
//
// Many of the _d_* functions further below suffer from the same problem.
// This is not an issue, because programs targeting Palm OS devices can use
// operators (+ - * / etc) instead of calling these functions directly.
// (GCC users may wish to use -lnfm -- see the documentation for details.)
//
// See the SDK's SampleCalc example for further discussion.

void	FlpBufferAToF(FlpDouble *result, const Char *s)
					FLOAT_TRAP(sysFloatAToF);

void	FlpBufferCorrectedAdd(FlpDouble *result,
	FlpDouble firstOperand, FlpDouble secondOperand, Int16 howAccurate)
					FLOAT_TRAP(sysFloatCorrectedAdd);

void	FlpBufferCorrectedSub(FlpDouble *result,
	FlpDouble firstOperand, FlpDouble secondOperand, Int16 howAccurate)
					FLOAT_TRAP(sysFloatCorrectedSub);

#endif

UInt32			FlpVersion(void)
					FLOAT_TRAP(sysFloatVersion);

void			FlpSelectorErrPrv (UInt16 flpSelector)
					;		// used only by NewFloatDispatch.c

// The following macros could be useful but are left undefined due to the
// confusion they might cause.  What was called a "float" in PalmOS v1.0 was
// really a 64-bit; in v2.0 "float" is only 32-bits and "double" is 64-bits.
// However, if a v1.0 program is converted to use the NewFloatMgr, these
// macros could be re-defined, or the native _d_ routines could be called.

//#define 		FlpLongToFloat(x)		_d_itod(x)		// similar to 1.0 call, but returns double
//#define 		FlpFloatToLong(f)		_d_dtoi(f)		// similar to 1.0 call, but takes a double
//#define 		FlpFloatToULong(f)	_d_dtou(f)		// similar to 1.0 call, but takes a double


/************************************************************
 * New Floating point emulator functions
 *************************************************************/

/*
 * These three functions define the interface to the (software) fpscr
 * of the sfpe. _fp_round not only sets the rounding mode according
 * the low two bits of its argument, but it also returns those masked
 * two bits. This provides some hope of compatibility with less capable
 * emulators, which support only rounding to nearest. A programmer
 * concerned about getting the rounding mode requested can test the
 * return value from _fp_round; it will indicate what the current mode is.
 *
 * Constants passed to and received from _fp_round are:
 *		flpToNearest, flpTowardZero, flpUpward, or flpDownward 
 */

Int32		_fp_round(Int32)			FLOAT_EM_TRAP(sysFloatEm_fp_round);

/*
 * Constants passed to _fp_set_fpscr and received from _fp_get_fpscr are:
 *		flpInvalid, flpOverflow, flpUnderflow, flpDivByZero, or flpInexact 
 */

Int32		_fp_get_fpscr(void)		FLOAT_EM_TRAP(sysFloatEm_fp_get_fpscr);
void			_fp_set_fpscr(Int32)	FLOAT_EM_TRAP(sysFloatEm_fp_set_fpscr);


/*
 * The shorthand here can be determined from the context:
 *		i	--> long (Int32)
 *		u	--> UInt32 (UInt32)
 *		ll	--> long long int
 *		ull	--> UInt32 long int
 *		f	--> float
 *		d	--> double
 *		q	--> long double (defaults to double in this implementaton)
 *		XtoY--> map of type X to a value of type Y
 */

FlpFloat			_f_utof(UInt32)								FLOAT_EM_TRAP(sysFloatEm_f_utof);
FlpFloat			_f_itof(Int32)							FLOAT_EM_TRAP(sysFloatEm_f_itof);
FlpFloat			_f_ulltof(sfpe_unsigned_long_long)	FLOAT_EM_TRAP(sysFloatEm_f_ulltof);
FlpFloat			_f_lltof(sfpe_long_long)				FLOAT_EM_TRAP(sysFloatEm_f_lltof);

FlpDouble		_d_utod(UInt32)								FLOAT_EM_TRAP(sysFloatEm_d_utod);
FlpDouble		_d_itod(Int32)							FLOAT_EM_TRAP(sysFloatEm_d_itod);
FlpDouble		_d_ulltod(sfpe_unsigned_long_long)	FLOAT_EM_TRAP(sysFloatEm_d_ulltod);
FlpDouble		_d_lltod(sfpe_long_long)				FLOAT_EM_TRAP(sysFloatEm_d_lltod);


FlpDouble		_f_ftod(FlpFloat)							FLOAT_EM_TRAP(sysFloatEm_f_ftod);
FlpFloat			_d_dtof(FlpDouble)						FLOAT_EM_TRAP(sysFloatEm_d_dtof);

FlpLongDouble	_f_ftoq(FlpFloat)							FLOAT_EM_TRAP(sysFloatEm_f_ftoq);
FlpFloat			_f_qtof(const FlpLongDouble *)		FLOAT_EM_TRAP(sysFloatEm_f_qtof);

FlpLongDouble	_d_dtoq(FlpDouble)						FLOAT_EM_TRAP(sysFloatEm_d_dtoq);
FlpDouble		_d_qtod(const FlpLongDouble *)		FLOAT_EM_TRAP(sysFloatEm_d_qtod);


UInt32							_f_ftou(FlpFloat)				FLOAT_EM_TRAP(sysFloatEm_f_ftou);
Int32						_f_ftoi(FlpFloat)				FLOAT_EM_TRAP(sysFloatEm_f_ftoi);

sfpe_unsigned_long_long	_f_ftoull(FlpFloat)			FLOAT_EM_TRAP(sysFloatEm_f_ftoull);
sfpe_long_long				_f_ftoll(FlpFloat)			FLOAT_EM_TRAP(sysFloatEm_f_ftoll);

UInt32							_d_dtou(FlpDouble)			FLOAT_EM_TRAP(sysFloatEm_d_dtou);
Int32						_d_dtoi(FlpDouble)			FLOAT_EM_TRAP(sysFloatEm_d_dtoi);

sfpe_unsigned_long_long	_d_dtoull(FlpDouble)			FLOAT_EM_TRAP(sysFloatEm_d_dtoull);
sfpe_long_long				_d_dtoll(FlpDouble)			FLOAT_EM_TRAP(sysFloatEm_d_dtoll);


/*
 * The comparison functions _T_Tcmp[e] compare their two arguments,
 * of type T, and return one of the four values defined below.
 * The functions _d_dcmpe and _f_fcmpe, in addition to returning
 * the comparison code, also set the invalid flag in the fpscr if
 * the operands are unordered. Two floating point values are unordered
 * when they enjoy no numerical relationship, as is the case when one
 * or both are NaNs.
 *
 * Return values for _d_cmp, _d_cmpe, _f_cmp, and _f_cmpe are:
 *		flpEqual, flpLess, flpGreater, or flpUnordered 
 *
 * The function shorthand is:
 *		eq	--> equal
 *		ne	--> not equal
 *		lt	--> less than
 *		le	--> less than or equal to
 *		gt	--> greater than
 *		ge	--> greater than or equal to
 *		un	--> unordered with
 *		or	--> ordered with (i.e. less than, equal to, or greater than)
 */

Int32		_f_cmp(FlpFloat, FlpFloat)			FLOAT_EM_TRAP(sysFloatEm_f_cmp);
Int32		_f_cmpe(FlpFloat, FlpFloat)		FLOAT_EM_TRAP(sysFloatEm_f_cmpe);
Int32		_f_feq(FlpFloat, FlpFloat)			FLOAT_EM_TRAP(sysFloatEm_f_feq);
Int32		_f_fne(FlpFloat, FlpFloat)			FLOAT_EM_TRAP(sysFloatEm_f_fne);
Int32		_f_flt(FlpFloat, FlpFloat)			FLOAT_EM_TRAP(sysFloatEm_f_flt);
Int32		_f_fle(FlpFloat, FlpFloat)			FLOAT_EM_TRAP(sysFloatEm_f_fle);
Int32		_f_fgt(FlpFloat, FlpFloat)			FLOAT_EM_TRAP(sysFloatEm_f_fgt);
Int32		_f_fge(FlpFloat, FlpFloat)			FLOAT_EM_TRAP(sysFloatEm_f_fge);
Int32		_f_fun(FlpFloat, FlpFloat)			FLOAT_EM_TRAP(sysFloatEm_f_fun);
Int32		_f_for(FlpFloat, FlpFloat)			FLOAT_EM_TRAP(sysFloatEm_f_for);

Int32		_d_cmp(FlpDouble, FlpDouble)		FLOAT_EM_TRAP(sysFloatEm_d_cmp);
Int32		_d_cmpe(FlpDouble, FlpDouble)		FLOAT_EM_TRAP(sysFloatEm_d_cmpe);
Int32		_d_feq(FlpDouble, FlpDouble)		FLOAT_EM_TRAP(sysFloatEm_d_feq);
Int32		_d_fne(FlpDouble, FlpDouble)		FLOAT_EM_TRAP(sysFloatEm_d_fne);
Int32		_d_flt(FlpDouble, FlpDouble)		FLOAT_EM_TRAP(sysFloatEm_d_flt);
Int32		_d_fle(FlpDouble, FlpDouble)		FLOAT_EM_TRAP(sysFloatEm_d_fle);
Int32		_d_fgt(FlpDouble, FlpDouble)		FLOAT_EM_TRAP(sysFloatEm_d_fgt);
Int32		_d_fge(FlpDouble, FlpDouble)		FLOAT_EM_TRAP(sysFloatEm_d_fge);
Int32		_d_fun(FlpDouble, FlpDouble)		FLOAT_EM_TRAP(sysFloatEm_d_fun);
Int32		_d_for(FlpDouble, FlpDouble)		FLOAT_EM_TRAP(sysFloatEm_d_for);


FlpFloat		_f_neg(FlpFloat)						FLOAT_EM_TRAP(sysFloatEm_f_neg);
FlpFloat		_f_add(FlpFloat, FlpFloat)			FLOAT_EM_TRAP(sysFloatEm_f_add);
FlpFloat		_f_mul(FlpFloat, FlpFloat)			FLOAT_EM_TRAP(sysFloatEm_f_mul);
FlpFloat		_f_sub(FlpFloat, FlpFloat)			FLOAT_EM_TRAP(sysFloatEm_f_sub);
FlpFloat		_f_div(FlpFloat, FlpFloat)			FLOAT_EM_TRAP(sysFloatEm_f_div);

FlpDouble	_d_neg(FlpDouble)						FLOAT_EM_TRAP(sysFloatEm_d_neg);
FlpDouble	_d_add(FlpDouble, FlpDouble)		FLOAT_EM_TRAP(sysFloatEm_d_add);
FlpDouble	_d_mul(FlpDouble, FlpDouble)		FLOAT_EM_TRAP(sysFloatEm_d_mul);
FlpDouble	_d_sub(FlpDouble, FlpDouble)		FLOAT_EM_TRAP(sysFloatEm_d_sub);
FlpDouble	_d_div(FlpDouble, FlpDouble)		FLOAT_EM_TRAP(sysFloatEm_d_div);


#ifdef __cplusplus
}
#endif


#endif
