1 /* Definitions of libc internal inline math functions implemented
2    by the m68881/2.
3    Copyright (C) 1991-2022 Free Software Foundation, Inc.
4    This file is part of the GNU C Library.
5 
6    The GNU C Library is free software; you can redistribute it and/or
7    modify it under the terms of the GNU Lesser General Public
8    License as published by the Free Software Foundation; either
9    version 2.1 of the License, or (at your option) any later version.
10 
11    The GNU C Library is distributed in the hope that it will be useful,
12    but WITHOUT ANY WARRANTY; without even the implied warranty of
13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14    Lesser General Public License for more details.
15 
16    You should have received a copy of the GNU Lesser General Public
17    License along with the GNU C Library.  If not, see
18    <https://www.gnu.org/licenses/>.  */
19 
20 #ifndef _MATHIMPL_H
21 #define _MATHIMPL_H
22 
23 /* This file contains the definitions of the inline math functions that
24    are only used internally inside libm, not visible to the user.  */
25 
26 #define __MATH_INLINE __extern_inline
27 
28 /* This is used when defining the functions themselves.  Define them with
29    __ names, and with `static inline' instead of `extern inline' so the
30    bodies will always be used, never an external function call.
31    Note: GCC 6 objects to __attribute__ ((__leaf__)) on static functions.  */
32 #define __m81_u(x)             __CONCAT(__,x)
33 #define __m81_inline           static __inline
34 #define __m81_nth(fn)          __NTH (fn)
35 
36 /* Define a math function.  */
37 #define __m81_defun(rettype, func, args, attrs)	\
38   __m81_inline rettype attrs			\
39   __m81_nth (__m81_u(func) args)
40 
41 /* Define the three variants of a math function that has a direct
42    implementation in the m68k fpu.  FUNC is the name for C (which will be
43    suffixed with f and l for the float and long double version, resp).  OP
44    is the name of the fpu operation (without leading f).  */
45 
46 # define __inline_mathop(func, op, attrs)			\
47   __inline_mathop1(double, func, op, attrs)			\
48   __inline_mathop1(float, __CONCAT(func,f), op, attrs)		\
49   __inline_mathop1(long double, __CONCAT(func,l), op, attrs)
50 
51 #define __inline_mathop1(float_type,func, op, attrs)			      \
52   __m81_defun (float_type, func, (float_type __mathop_x), attrs)	      \
53   {									      \
54     float_type __result;						      \
55     __asm __volatile__ ("f" __STRING(op) "%.x %1, %0"			      \
56 			: "=f" (__result) : "f" (__mathop_x));		      \
57     return __result;							      \
58   }
59 
60 __inline_mathop(__atan, atan,)
61 __inline_mathop(__cos, cos,)
62 __inline_mathop(__sin, sin,)
63 __inline_mathop(__tan, tan,)
64 __inline_mathop(__tanh, tanh,)
65 __inline_mathop(__fabs, abs, __attribute__ ((__const__)))
66 
67 __inline_mathop(__rint, int,)
68 __inline_mathop(__expm1, etoxm1,)
69 __inline_mathop(__log1p, lognp1,)
70 
71 __inline_mathop(__significand, getman,)
72 
73 __inline_mathop(__trunc, intrz, __attribute__ ((__const__)))
74 
75 
76 /* This macro contains the definition for the rest of the inline
77    functions, using FLOAT_TYPE as the domain type and M as a macro
78    that adds the suffix for the function names.  */
79 
80 #define __inline_functions(float_type, m)				  \
81 __m81_defun (float_type, m(__floor), (float_type __x),			  \
82 	     __attribute__ ((__const__)))				  \
83 {									  \
84   float_type __result;							  \
85   unsigned long int __ctrl_reg;						  \
86   __asm __volatile__ ("fmove%.l %!, %0" : "=dm" (__ctrl_reg));		  \
87   /* Set rounding towards negative infinity.  */			  \
88   __asm __volatile__ ("fmove%.l %0, %!" : /* No outputs.  */		  \
89 		      : "dmi" ((__ctrl_reg & ~0x10) | 0x20));		  \
90   /* Convert X to an integer, using -Inf rounding.  */			  \
91   __asm __volatile__ ("fint%.x %1, %0" : "=f" (__result) : "f" (__x));	  \
92   /* Restore the previous rounding mode.  */				  \
93   __asm __volatile__ ("fmove%.l %0, %!" : /* No outputs.  */		  \
94 		      : "dmi" (__ctrl_reg));				  \
95   return __result;							  \
96 }									  \
97 									  \
98 __m81_defun (float_type, m(__ceil), (float_type __x),			  \
99 	     __attribute__ ((__const__)))				  \
100 {									  \
101   float_type __result;							  \
102   unsigned long int __ctrl_reg;						  \
103   __asm __volatile__ ("fmove%.l %!, %0" : "=dm" (__ctrl_reg));		  \
104   /* Set rounding towards positive infinity.  */			  \
105   __asm __volatile__ ("fmove%.l %0, %!" : /* No outputs.  */		  \
106 		      : "dmi" (__ctrl_reg | 0x30));			  \
107   /* Convert X to an integer, using +Inf rounding.  */			  \
108   __asm __volatile__ ("fint%.x %1, %0" : "=f" (__result) : "f" (__x));	  \
109   /* Restore the previous rounding mode.  */				  \
110   __asm __volatile__ ("fmove%.l %0, %!" : /* No outputs.  */		  \
111 		      : "dmi" (__ctrl_reg));				  \
112   return __result;							  \
113 }
114 
115 #define __CONCAT_d(arg) arg
116 #define __CONCAT_f(arg) arg ## f
117 #define __CONCAT_l(arg) arg ## l
__inline_functions(double,__CONCAT_d)118 __inline_functions(double, __CONCAT_d)
119 __inline_functions(float, __CONCAT_f)
120 __inline_functions(long double, __CONCAT_l)
121 #undef __inline_functions
122 
123 # define __inline_functions(float_type, m)				  \
124 __m81_defun (int, m(__isinf), (float_type __value),			  \
125 	     __attribute__ ((__const__)))				  \
126 {									  \
127   /* There is no branch-condition for infinity,				  \
128      so we must extract and examine the condition codes manually.  */	  \
129   unsigned long int __fpsr;						  \
130   __asm ("ftst%.x %1\n"							  \
131 	 "fmove%.l %/fpsr, %0" : "=dm" (__fpsr) : "f" (__value));	  \
132   return (__fpsr & (2 << 24)) ? (__fpsr & (8 << 24) ? -1 : 1) : 0;	  \
133 }									  \
134 									  \
135 __m81_defun (int, m(__finite), (float_type __value),			  \
136 	     __attribute__ ((__const__)))				  \
137 {									  \
138   /* There is no branch-condition for infinity, so we must extract and	  \
139      examine the condition codes manually.  */				  \
140   unsigned long int __fpsr;						  \
141   __asm ("ftst%.x %1\n"							  \
142 	 "fmove%.l %/fpsr, %0" : "=dm" (__fpsr) : "f" (__value));	  \
143   return (__fpsr & (3 << 24)) == 0;					  \
144 }									  \
145 									  \
146 __m81_defun (float_type, m(__scalbn),					  \
147 	     (float_type __x, int __n),)				  \
148 {									  \
149   float_type __result;							  \
150   __asm __volatile__  ("fscale%.l %1, %0" : "=f" (__result)		  \
151 		       : "dmi" (__n), "0" (__x));			  \
152   return __result;							  \
153 }
154 
155 __inline_functions(double, __CONCAT_d)
156 __inline_functions(float, __CONCAT_f)
157 __inline_functions(long double, __CONCAT_l)
158 #undef __inline_functions
159 
160 # define __inline_functions(float_type, m)				  \
161 __m81_defun (int, m(__isnan), (float_type __value),			  \
162 	     __attribute__ ((__const__)))			  	  \
163 {									  \
164   char __result;							  \
165   __asm ("ftst%.x %1\n"							  \
166 	 "fsun %0" : "=dm" (__result) : "f" (__value));			  \
167   return __result;							  \
168 }
169 
170 __inline_functions(double, __CONCAT_d)
171 __inline_functions(float, __CONCAT_f)
172 __inline_functions(long double, __CONCAT_l)
173 #undef __inline_functions
174 
175 # define __inline_functions(float_type, m)				  \
176 __m81_defun (float_type, m(__scalbln),					  \
177 	     (float_type __x, long int __n),)				  \
178 {									  \
179   return m(__scalbn) (__x, __n);					  \
180 }									  \
181 									  \
182 __m81_defun (float_type, m(__nearbyint), (float_type __x),)		  \
183 {									  \
184   float_type __result;							  \
185   unsigned long int __ctrl_reg;						  \
186   __asm __volatile__ ("fmove%.l %!, %0" : "=dm" (__ctrl_reg));		  \
187   /* Temporarily disable the inexact exception.  */			  \
188   __asm __volatile__ ("fmove%.l %0, %!" : /* No outputs.  */		  \
189 		      : "dmi" (__ctrl_reg & ~0x200));			  \
190   __asm __volatile__ ("fint%.x %1, %0" : "=f" (__result) : "f" (__x));	  \
191   __asm __volatile__ ("fmove%.l %0, %!" : /* No outputs.  */		  \
192 		      : "dmi" (__ctrl_reg));				  \
193   return __result;							  \
194 }									  \
195 									  \
196 __m81_defun (long int, m(__lrint), (float_type __x),)			  \
197 {									  \
198   long int __result;							  \
199   __asm __volatile__ ("fmove%.l %1, %0" : "=dm" (__result) : "f" (__x));  \
200   return __result;							  \
201 }
202 
203 __inline_functions (double, __CONCAT_d)
204 __inline_functions (float, __CONCAT_f)
205 __inline_functions (long double, __CONCAT_l)
206 #undef __inline_functions
207 
208 #define __inline_functions(float_type, m)				\
209 __m81_inline void							\
210 __m81_nth (__m81_u(m(__sincos))						\
211 	   (float_type __x, float_type *__sinx, float_type *__cosx))	\
212 {									\
213   __asm __volatile__ ("fsincos%.x %2,%1:%0"				\
214 		      : "=f" (*__sinx), "=f" (*__cosx) : "f" (__x));	\
215 }
216 
217 __inline_functions (double, __CONCAT_d)
218 __inline_functions (float, __CONCAT_f)
219 __inline_functions (long double, __CONCAT_l)
220 #undef __inline_functions
221 
222 #undef __CONCAT_d
223 #undef __CONCAT_f
224 #undef __CONCAT_l
225 
226 /* Define the three variants of a math function that has a direct
227    implementation in the m68k fpu.  FUNC is the name for C (which will be
228    suffixed with f and l for the float and long double version, resp).  OP
229    is the name of the fpu operation (without leading f).  */
230 
231 #define __inline_mathop(func, op, attrs)			\
232   __inline_mathop1(double, func, op, attrs)			\
233   __inline_mathop1(float, __CONCAT(func,f), op, attrs)		\
234   __inline_mathop1(long double, __CONCAT(func,l), op, attrs)
235 
236 #define __inline_mathop1(float_type,func, op, attrs)			      \
237   __m81_defun (float_type, func, (float_type __mathop_x), attrs)	      \
238   {									      \
239     float_type __result;						      \
240     __asm __volatile__ ("f" __STRING(op) "%.x %1, %0"			      \
241 			: "=f" (__result) : "f" (__mathop_x));		      \
242     return __result;							      \
243   }
244 
245 __inline_mathop	(__ieee754_acos, acos,)
246 __inline_mathop	(__ieee754_asin, asin,)
247 __inline_mathop	(__ieee754_cosh, cosh,)
248 __inline_mathop	(__ieee754_sinh, sinh,)
249 __inline_mathop	(__ieee754_exp, etox,)
250 __inline_mathop	(__ieee754_exp2, twotox,)
251 __inline_mathop	(__ieee754_exp10, tentox,)
252 __inline_mathop	(__ieee754_log10, log10,)
253 __inline_mathop	(__ieee754_log2, log2,)
254 __inline_mathop	(__ieee754_log, logn,)
255 __inline_mathop	(__ieee754_sqrt, sqrt,)
256 __inline_mathop	(__ieee754_atanh, atanh,)
257 
258 __m81_defun (double, __ieee754_remainder, (double __x, double __y),)
259 {
260   double __result;
261   __asm ("frem%.x %1, %0" : "=f" (__result) : "f" (__y), "0" (__x));
262   return __result;
263 }
264 
265 __m81_defun (float, __ieee754_remainderf, (float __x, float __y),)
266 {
267   float __result;
268   __asm ("frem%.x %1, %0" : "=f" (__result) : "f" (__y), "0" (__x));
269   return __result;
270 }
271 
272 __m81_defun (long double,
273 	     __ieee754_remainderl, (long double __x, long double __y),)
274 {
275   long double __result;
276   __asm ("frem%.x %1, %0" : "=f" (__result) : "f" (__y), "0" (__x));
277   return __result;
278 }
279 
280 __m81_defun (double, __ieee754_fmod, (double __x, double __y),)
281 {
282   double __result;
283   __asm ("fmod%.x %1, %0" : "=f" (__result) : "f" (__y), "0" (__x));
284   return __result;
285 }
286 
287 __m81_defun (float, __ieee754_fmodf, (float __x, float __y),)
288 {
289   float __result;
290   __asm ("fmod%.x %1, %0" : "=f" (__result) : "f" (__y), "0" (__x));
291   return __result;
292 }
293 
294 __m81_defun (long double,
295 	     __ieee754_fmodl, (long double __x, long double __y),)
296 {
297   long double __result;
298   __asm ("fmod%.x %1, %0" : "=f" (__result) : "f" (__y), "0" (__x));
299   return __result;
300 }
301 
302 /* Get the m68881 condition codes, to quickly check multiple conditions.  */
303 static __inline__ unsigned long
__m81_test(long double __val)304 __m81_test (long double __val)
305 {
306   unsigned long __fpsr;
307   __asm ("ftst%.x %1; fmove%.l %/fpsr,%0" : "=dm" (__fpsr) : "f" (__val));
308   return __fpsr;
309 }
310 
311 /* Bit values returned by __m81_test.  */
312 #define __M81_COND_NAN  (1 << 24)
313 #define __M81_COND_INF  (2 << 24)
314 #define __M81_COND_ZERO (4 << 24)
315 #define __M81_COND_NEG  (8 << 24)
316 
317 #endif /* _MATHIMPL_H  */
318