/*-
 * Copyright (c) 2004 Stefan Farfeleder.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * $FreeBSD$
 */

#ifndef _TGMATH_H_
#define	_TGMATH_H_

#include <complex.h>
#include <math.h>

/*
 * This implementation of <tgmath.h> requires two implementation-dependent
 * macros to be defined:
 * __tg_impl_simple(x, y, z, fn, fnf, fnl, ...)
 *	Invokes fnl() if the corresponding real type of x, y or z is long
 *	double, fn() if it is double or any has an integer type, and fnf()
 *	otherwise.
 * __tg_impl_full(x, y, z, fn, fnf, fnl, cfn, cfnf, cfnl, ...)
 *	Invokes [c]fnl() if the corresponding real type of x, y or z is long
 *	double, [c]fn() if it is double or any has an integer type, and
 *	[c]fnf() otherwise.  The function with the 'c' prefix is called if
 *	any of x, y or z is a complex number.
 * Both macros call the chosen function with all additional arguments passed
 * to them, as given by __VA_ARGS__.
 *
 * Note that these macros cannot be implemented with C's ?: operator,
 * because the return type of the whole expression would incorrectly be long
 * double complex regardless of the argument types.
 */

#if __GNUC_PREREQ__(3, 1)
#define	__tg_type(e, t)	__builtin_types_compatible_p(__typeof__(e), t)
#define	__tg_type3(e1, e2, e3, t)					\
	(__tg_type(e1, t) || __tg_type(e2, t) || __tg_type(e3, t))
#define	__tg_type_corr(e1, e2, e3, t)					\
	(__tg_type3(e1, e2, e3, t) || __tg_type3(e1, e2, e3, t _Complex))
#define	__tg_integer(e1, e2, e3)					\
	(((__typeof__(e1))1.5 == 1) || ((__typeof__(e2))1.5 == 1) ||	\
	    ((__typeof__(e3))1.5 == 1))
#define	__tg_is_complex(e1, e2, e3)					\
	(__tg_type3(e1, e2, e3, float _Complex) ||			\
	    __tg_type3(e1, e2, e3, double _Complex) ||			\
	    __tg_type3(e1, e2, e3, long double _Complex)) ||		\
	    __tg_type3(e1, e2, e3, __typeof__(_Complex_I))

#define	__tg_impl_simple(x, y, z, fn, fnf, fnl, ...)			\
	__builtin_choose_expr(__tg_type_corr(x, y, z, long double),	\
	    fnl(__VA_ARGS__), __builtin_choose_expr(			\
		__tg_type_corr(x, y, z, double) || __tg_integer(x, y, z),\
		fn(__VA_ARGS__), fnf(__VA_ARGS__)))

#define	__tg_impl_full(x, y, z, fn, fnf, fnl, cfn, cfnf, cfnl, ...)	\
	__builtin_choose_expr(__tg_is_complex(x, y, z),			\
	    __tg_impl_simple(x, y, z, cfn, cfnf, cfnl, __VA_ARGS__),	\
	    __tg_impl_simple(x, y, z, fn, fnf, fnl, __VA_ARGS__))

#else	/* __GNUC__ */
#error "<tgmath.h> not implemented for this compiler"
#endif	/* !__GNUC__ */

/* Macros to save lots of repetition below */
#define	__tg_simple(x, fn)						\
	__tg_impl_simple(x, x, x, fn, fn##f, fn##l, x)
#define	__tg_simple2(x, y, fn)						\
	__tg_impl_simple(x, x, y, fn, fn##f, fn##l, x, y)
#define	__tg_simplev(x, fn, ...)					\
	__tg_impl_simple(x, x, x, fn, fn##f, fn##l, __VA_ARGS__)
#define	__tg_full(x, fn)						\
	__tg_impl_full(x, x, x, fn, fn##f, fn##l, c##fn, c##fn##f, c##fn##l, x)

/* 7.22#4 -- These macros expand to real or complex functions, depending on
 * the type of their arguments. */
#define	acos(x)		__tg_full(x, acos)
#define	asin(x)		__tg_full(x, asin)
#define	atan(x)		__tg_full(x, atan)
#define	acosh(x)	__tg_full(x, acosh)
#define	asinh(x)	__tg_full(x, asinh)
#define	atanh(x)	__tg_full(x, atanh)
#define	cos(x)		__tg_full(x, cos)
#define	sin(x)		__tg_full(x, sin)
#define	tan(x)		__tg_full(x, tan)
#define	cosh(x)		__tg_full(x, cosh)
#define	sinh(x)		__tg_full(x, sinh)
#define	tanh(x)		__tg_full(x, tanh)
#define	exp(x)		__tg_full(x, exp)
#define	log(x)		__tg_full(x, log)
#define	pow(x, y)	__tg_impl_full(x, x, y, pow, powf, powl,	\
			    cpow, cpowf, cpowl, x, y)
#define	sqrt(x)		__tg_full(x, sqrt)

/* "The corresponding type-generic macro for fabs and cabs is fabs." */
#define	fabs(x)		__tg_impl_full(x, x, x, fabs, fabsf, fabsl,	\
    			    cabs, cabsf, cabsl, x)

/* 7.22#5 -- These macros are only defined for arguments with real type. */
#define	atan2(x, y)	__tg_simple2(x, y, atan2)
#define	cbrt(x)		__tg_simple(x, cbrt)
#define	ceil(x)		__tg_simple(x, ceil)
#define	copysign(x, y)	__tg_simple2(x, y, copysign)
#define	erf(x)		__tg_simple(x, erf)
#define	erfc(x)		__tg_simple(x, erfc)
#define	exp2(x)		__tg_simple(x, exp2)
#define	expm1(x)	__tg_simple(x, expm1)
#define	fdim(x, y)	__tg_simple2(x, y, fdim)
#define	floor(x)	__tg_simple(x, floor)
#define	fma(x, y, z)	__tg_impl_simple(x, y, z, fma, fmaf, fmal, x, y, z)
#define	fmax(x, y)	__tg_simple2(x, y, fmax)
#define	fmin(x, y)	__tg_simple2(x, y, fmin)
#define	fmod(x, y)	__tg_simple2(x, y, fmod)
#define	frexp(x, y)	__tg_simplev(x, frexp, x, y)
#define	hypot(x, y)	__tg_simple2(x, y, hypot)
#define	ilogb(x)	__tg_simple(x, ilogb)
#define	ldexp(x, y)	__tg_simplev(x, ldexp, x, y)
#define	lgamma(x)	__tg_simple(x, lgamma)
#define	llrint(x)	__tg_simple(x, llrint)
#define	llround(x)	__tg_simple(x, llround)
#define	log10(x)	__tg_simple(x, log10)
#define	log1p(x)	__tg_simple(x, log1p)
#define	log2(x)		__tg_simple(x, log2)
#define	logb(x)		__tg_simple(x, logb)
#define	lrint(x)	__tg_simple(x, lrint)
#define	lround(x)	__tg_simple(x, lround)
#define	nearbyint(x)	__tg_simple(x, nearbyint)
#define	nextafter(x, y)	__tg_simple2(x, y, nextafter)
#define	nexttoward(x, y) __tg_simplev(x, nexttoward, x, y)
#define	remainder(x, y)	__tg_simple2(x, y, remainder)
#define	remquo(x, y, z)	__tg_impl_simple(x, x, y, remquo, remquof,	\
			    remquol, x, y, z)
#define	rint(x)		__tg_simple(x, rint)
#define	round(x)	__tg_simple(x, round)
#define	scalbn(x, y)	__tg_simplev(x, scalbn, x, y)
#define	scalbln(x, y)	__tg_simplev(x, scalbln, x, y)
#define	tgamma(x)	__tg_simple(x, tgamma)
#define	trunc(x)	__tg_simple(x, trunc)

/* 7.22#6 -- These macros always expand to complex functions. */
#define	carg(x)		__tg_simple(x, carg)
#define	cimag(x)	__tg_simple(x, cimag)
#define	conj(x)		__tg_simple(x, conj)
#define	cproj(x)	__tg_simple(x, cproj)
#define	creal(x)	__tg_simple(x, creal)

#endif /* !_TGMATH_H_ */