1 /*
2  * fp_emu.h
3  *
4  * Copyright Roman Zippel, 1997.  All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, and the entire permission notice in its entirety,
11  *    including the disclaimer of warranties.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. The name of the author may not be used to endorse or promote
16  *    products derived from this software without specific prior
17  *    written permission.
18  *
19  * ALTERNATIVELY, this product may be distributed under the terms of
20  * the GNU General Public License, in which case the provisions of the GPL are
21  * required INSTEAD OF the above restrictions.  (This clause is
22  * necessary due to a potential bad interaction between the GPL and
23  * the restrictions contained in a BSD-style copyright.)
24  *
25  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
26  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
27  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
28  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
29  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
30  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
31  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
33  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
35  * OF THE POSSIBILITY OF SUCH DAMAGE.
36  */
37 
38 #ifndef _FP_EMU_H
39 #define _FP_EMU_H
40 
41 #ifdef __ASSEMBLY__
42 #include <asm/asm-offsets.h>
43 #endif
44 #include <asm/math-emu.h>
45 
46 #ifndef __ASSEMBLY__
47 
48 #define IS_INF(a) ((a)->exp == 0x7fff)
49 #define IS_ZERO(a) ((a)->mant.m64 == 0)
50 
51 
52 #define fp_set_sr(bit) ({					\
53 	FPDATA->fpsr |= 1 << (bit);				\
54 })
55 
56 #define fp_set_quotient(quotient) ({				\
57 	FPDATA->fpsr &= 0xff00ffff;				\
58 	FPDATA->fpsr |= ((quotient) & 0xff) << 16;		\
59 })
60 
61 /* linkage for several useful functions */
62 
63 /* Normalize the extended struct, return 0 for a NaN */
64 #define fp_normalize_ext(fpreg) ({				\
65 	register struct fp_ext *reg asm ("a0") = fpreg;		\
66 	register int res asm ("d0");				\
67 								\
68 	asm volatile ("jsr fp_conv_ext2ext"			\
69 			: "=d" (res) : "a" (reg)		\
70 			: "a1", "d1", "d2", "memory");		\
71 	res;							\
72 })
73 
74 #define fp_copy_ext(dest, src) ({				\
75 	*dest = *src;						\
76 })
77 
78 #define fp_monadic_check(dest, src) ({				\
79 	fp_copy_ext(dest, src);					\
80 	if (!fp_normalize_ext(dest))				\
81 		return dest;					\
82 })
83 
84 #define fp_dyadic_check(dest, src) ({				\
85 	if (!fp_normalize_ext(dest))				\
86 		return dest;					\
87 	if (!fp_normalize_ext(src)) {				\
88 		fp_copy_ext(dest, src);				\
89 		return dest;					\
90 	}							\
91 })
92 
93 extern const struct fp_ext fp_QNaN;
94 extern const struct fp_ext fp_Inf;
95 
96 #define fp_set_nan(dest) ({					\
97 	fp_set_sr(FPSR_EXC_OPERR);				\
98 	*dest = fp_QNaN;					\
99 })
100 
101 /* TODO check rounding mode? */
102 #define fp_set_ovrflw(dest) ({					\
103 	fp_set_sr(FPSR_EXC_OVFL);				\
104 	dest->exp = 0x7fff;					\
105 	dest->mant.m64 = 0;					\
106 })
107 
108 #define fp_conv_ext2long(src) ({				\
109 	register struct fp_ext *__src asm ("a0") = src;		\
110 	register int __res asm ("d0");				\
111 								\
112 	asm volatile ("jsr fp_conv_ext2long"			\
113 			: "=d" (__res) : "a" (__src)		\
114 			: "a1", "d1", "d2", "memory");		\
115 	__res;							\
116 })
117 
118 #define fp_conv_long2ext(dest, src) ({				\
119 	register struct fp_ext *__dest asm ("a0") = dest;	\
120 	register int __src asm ("d0") = src;			\
121 								\
122 	asm volatile ("jsr fp_conv_ext2long"			\
123 			: : "d" (__src), "a" (__dest)		\
124 			: "a1", "d1", "d2", "memory");		\
125 })
126 
127 #else /* __ASSEMBLY__ */
128 
129 /*
130  * set, reset or clear a bit in the fp status register
131  */
132 .macro	fp_set_sr	bit
133 	bset	#(\bit&7),(FPD_FPSR+3-(\bit/8),FPDATA)
134 .endm
135 
136 .macro	fp_clr_sr	bit
137 	bclr	#(\bit&7),(FPD_FPSR+3-(\bit/8),FPDATA)
138 .endm
139 
140 .macro	fp_tst_sr	bit
141 	btst	#(\bit&7),(FPD_FPSR+3-(\bit/8),FPDATA)
142 .endm
143 
144 #endif /* __ASSEMBLY__ */
145 
146 #endif /* _FP_EMU_H */
147