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 27 #include <stdio.h> 28 29 static int dalign; 30 typedef struct 31 Akind { 32 char *name; 33 int kind; 34 } Akind; 35 36 static Akind 37 IEEE_8087 = { "IEEE_8087", 1 }, 38 IEEE_MC68k = { "IEEE_MC68k", 2 }, 39 IBM = { "IBM", 3 }, 40 VAX = { "VAX", 4 }, 41 CRAY = { "CRAY", 5}; 42 43 static Akind * 44 Lcheck() 45 { 46 union { 47 double d; 48 long L[2]; 49 } u; 50 struct { 51 double d; 52 long L; 53 } x[2]; 54 55 if (sizeof(x) > 2*(sizeof(double) + sizeof(long))) 56 dalign = 1; 57 u.L[0] = u.L[1] = 0; 58 u.d = 1e13; 59 if (u.L[0] == 1117925532 && u.L[1] == -448790528) 60 return &IEEE_MC68k; 61 if (u.L[1] == 1117925532 && u.L[0] == -448790528) 62 return &IEEE_8087; 63 if (u.L[0] == -2065213935 && u.L[1] == 10752) 64 return &VAX; 65 if (u.L[0] == 1267827943 && u.L[1] == 704643072) 66 return &IBM; 67 return 0; 68 } 69 70 static Akind * 71 icheck() 72 { 73 union { 74 double d; 75 int L[2]; 76 } u; 77 struct { 78 double d; 79 int L; 80 } x[2]; 81 82 if (sizeof(x) > 2*(sizeof(double) + sizeof(int))) 83 dalign = 1; 84 u.L[0] = u.L[1] = 0; 85 u.d = 1e13; 86 if (u.L[0] == 1117925532 && u.L[1] == -448790528) 87 return &IEEE_MC68k; 88 if (u.L[1] == 1117925532 && u.L[0] == -448790528) 89 return &IEEE_8087; 90 if (u.L[0] == -2065213935 && u.L[1] == 10752) 91 return &VAX; 92 if (u.L[0] == 1267827943 && u.L[1] == 704643072) 93 return &IBM; 94 return 0; 95 } 96 97 char *emptyfmt = ""; /* avoid possible warning message with printf("") */ 98 99 static Akind * 100 ccheck() 101 { 102 union { 103 double d; 104 long L; 105 } u; 106 long Cray1; 107 108 /* Cray1 = 4617762693716115456 -- without overflow on non-Crays */ 109 Cray1 = printf(emptyfmt) < 0 ? 0 : 4617762; 110 if (printf(emptyfmt, Cray1) >= 0) 111 Cray1 = 1000000*Cray1 + 693716; 112 if (printf(emptyfmt, Cray1) >= 0) 113 Cray1 = 1000000*Cray1 + 115456; 114 u.d = 1e13; 115 if (u.L == Cray1) 116 return &CRAY; 117 return 0; 118 } 119 120 static int 121 fzcheck() 122 { 123 double a, b; 124 int i; 125 126 a = 1.; 127 b = .1; 128 for(i = 155;; b *= b, i >>= 1) { 129 if (i & 1) { 130 a *= b; 131 if (i == 1) 132 break; 133 } 134 } 135 b = a * a; 136 return b == 0.; 137 } 138 139 int 140 main() 141 { 142 Akind *a = 0; 143 int Ldef = 0; 144 FILE *f; 145 146 #ifdef WRITE_ARITH_H /* for Symantec's buggy "make" */ 147 f = fopen("arith.h", "w"); 148 if (!f) { 149 printf("Cannot open arith.h\n"); 150 return 1; 151 } 152 #else 153 f = stdout; 154 #endif 155 156 if (sizeof(double) == 2*sizeof(long)) 157 a = Lcheck(); 158 else if (sizeof(double) == 2*sizeof(int)) { 159 Ldef = 1; 160 a = icheck(); 161 } 162 else if (sizeof(double) == sizeof(long)) 163 a = ccheck(); 164 if (a) { 165 fprintf(f, "#define %s\n#define Arith_Kind_ASL %d\n", 166 a->name, a->kind); 167 if (Ldef) 168 fprintf(f, "#define Long int\n#define Intcast (int)(long)\n"); 169 if (dalign) 170 fprintf(f, "#define Double_Align\n"); 171 if (sizeof(char*) == 8) 172 fprintf(f, "#define X64_bit_pointers\n"); 173 #ifndef NO_LONG_LONG 174 if (sizeof(long long) < 8) 175 #endif 176 fprintf(f, "#define NO_LONG_LONG\n"); 177 if (a->kind <= 2 && fzcheck()) 178 fprintf(f, "#define Sudden_Underflow\n"); 179 return 0; 180 } 181 fprintf(f, "/* Unknown arithmetic */\n"); 182 return 1; 183 } 184