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1 /****************************************************************
2 Copyright (C) 1997, 1998 Lucent Technologies
3 All Rights Reserved
4 
5 Permission to use, copy, modify, and distribute this software and
6 its documentation for any purpose and without fee is hereby
7 granted, provided that the above copyright notice appear in all
8 copies and that both that the copyright notice and this
9 permission notice and warranty disclaimer appear in supporting
10 documentation, and that the name of Lucent or any of its entities
11 not be used in advertising or publicity pertaining to
12 distribution of the software without specific, written prior
13 permission.
14 
15 LUCENT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
16 INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS.
17 IN NO EVENT SHALL LUCENT OR ANY OF ITS ENTITIES BE LIABLE FOR ANY
18 SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
19 WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER
20 IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
21 ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF
22 THIS SOFTWARE.
23 ****************************************************************/
24 
25 /* Try to deduce arith.h from arithmetic properties. */
26 #ifdef MINGW_BUILD_GEN
27 
28 #include <stdio.h>
29 
30  static int dalign;
31  typedef struct
32 Akind {
33 	char *name;
34 	int   kind;
35 	} Akind;
36 
37  static Akind
38 IEEE_8087	= { "IEEE_8087", 1 },
39 IEEE_MC68k	= { "IEEE_MC68k", 2 },
40 IBM		= { "IBM", 3 },
41 VAX		= { "VAX", 4 },
42 CRAY		= { "CRAY", 5};
43 
44  static Akind *
Lcheck()45 Lcheck()
46 {
47 	union {
48 		double d;
49 		long L[2];
50 		} u;
51 	struct {
52 		double d;
53 		long L;
54 		} x[2];
55 
56 	if (sizeof(x) > 2*(sizeof(double) + sizeof(long)))
57 		dalign = 1;
58 	u.L[0] = u.L[1] = 0;
59 	u.d = 1e13;
60 	if (u.L[0] == 1117925532 && u.L[1] == -448790528)
61 		return &IEEE_MC68k;
62 	if (u.L[1] == 1117925532 && u.L[0] == -448790528)
63 		return &IEEE_8087;
64 	if (u.L[0] == -2065213935 && u.L[1] == 10752)
65 		return &VAX;
66 	if (u.L[0] == 1267827943 && u.L[1] == 704643072)
67 		return &IBM;
68 	return 0;
69 	}
70 
71  static Akind *
icheck()72 icheck()
73 {
74 	union {
75 		double d;
76 		int L[2];
77 		} u;
78 	struct {
79 		double d;
80 		int L;
81 		} x[2];
82 
83 	if (sizeof(x) > 2*(sizeof(double) + sizeof(int)))
84 		dalign = 1;
85 	u.L[0] = u.L[1] = 0;
86 	u.d = 1e13;
87 	if (u.L[0] == 1117925532 && u.L[1] == -448790528)
88 		return &IEEE_MC68k;
89 	if (u.L[1] == 1117925532 && u.L[0] == -448790528)
90 		return &IEEE_8087;
91 	if (u.L[0] == -2065213935 && u.L[1] == 10752)
92 		return &VAX;
93 	if (u.L[0] == 1267827943 && u.L[1] == 704643072)
94 		return &IBM;
95 	return 0;
96 	}
97 
98 char *emptyfmt = "";	/* avoid possible warning message with printf("") */
99 
100  static Akind *
ccheck()101 ccheck()
102 {
103 	union {
104 		double d;
105 		long L;
106 		} u;
107 	long Cray1;
108 
109 	/* Cray1 = 4617762693716115456 -- without overflow on non-Crays */
110 	Cray1 = printf(emptyfmt) < 0 ? 0 : 4617762;
111 	if (printf(emptyfmt, Cray1) >= 0)
112 		Cray1 = 1000000*Cray1 + 693716;
113 	if (printf(emptyfmt, Cray1) >= 0)
114 		Cray1 = 1000000*Cray1 + 115456;
115 	u.d = 1e13;
116 	if (u.L == Cray1)
117 		return &CRAY;
118 	return 0;
119 	}
120 
121  static int
fzcheck()122 fzcheck()
123 {
124 	double a, b;
125 	int i;
126 
127 	a = 1.;
128 	b = .1;
129 	for(i = 155;; b *= b, i >>= 1) {
130 		if (i & 1) {
131 			a *= b;
132 			if (i == 1)
133 				break;
134 			}
135 		}
136 	b = a * a;
137 	return b == 0.;
138 	}
139 
140  int
main()141 main()
142 {
143 	Akind *a = 0;
144 	int Ldef = 0;
145 	FILE *f;
146 
147 #ifdef WRITE_ARITH_H	/* for Symantec's buggy "make" */
148 	f = fopen("arith.h", "w");
149 	if (!f) {
150 		printf("Cannot open arith.h\n");
151 		return 1;
152 		}
153 #else
154 	f = stdout;
155 #endif
156 
157 	if (sizeof(double) == 2*sizeof(long))
158 		a = Lcheck();
159 	else if (sizeof(double) == 2*sizeof(int)) {
160 		Ldef = 1;
161 		a = icheck();
162 		}
163 	else if (sizeof(double) == sizeof(long))
164 		a = ccheck();
165 	if (a) {
166 		fprintf(f, "#define %s\n#define Arith_Kind_ASL %d\n",
167 			a->name, a->kind);
168 		if (Ldef)
169 			fprintf(f, "#define Long int\n#define Intcast (int)(long)\n");
170 		if (dalign)
171 			fprintf(f, "#define Double_Align\n");
172 		if (sizeof(char*) == 8)
173 			fprintf(f, "#define X64_bit_pointers\n");
174 #ifndef NO_LONG_LONG
175 		if (sizeof(long long) < 8)
176 #endif
177 			fprintf(f, "#define NO_LONG_LONG\n");
178 		if (a->kind <= 2 && fzcheck())
179 			fprintf(f, "#define Sudden_Underflow\n");
180 		return 0;
181 		}
182 	fprintf(f, "/* Unknown arithmetic */\n");
183 	return 1;
184 	}
185 #endif /* MINGW_BUILD_GEN */
186 
187