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 main() 140 { 141 Akind *a = 0; 142 int Ldef = 0; 143 FILE *f; 144 145 #ifdef WRITE_ARITH_H /* for Symantec's buggy "make" */ 146 f = fopen("arith.h", "w"); 147 if (!f) { 148 printf("Cannot open arith.h\n"); 149 return 1; 150 } 151 #else 152 f = stdout; 153 #endif 154 155 if (sizeof(double) == 2*sizeof(long)) 156 a = Lcheck(); 157 else if (sizeof(double) == 2*sizeof(int)) { 158 Ldef = 1; 159 a = icheck(); 160 } 161 else if (sizeof(double) == sizeof(long)) 162 a = ccheck(); 163 if (a) { 164 fprintf(f, "#define %s\n#define Arith_Kind_ASL %d\n", 165 a->name, a->kind); 166 if (Ldef) 167 fprintf(f, "#define Long int\n#define Intcast (int)(long)\n"); 168 if (dalign) 169 fprintf(f, "#define Double_Align\n"); 170 if (sizeof(char*) == 8) 171 fprintf(f, "#define X64_bit_pointers\n"); 172 #ifndef NO_LONG_LONG 173 if (sizeof(long long) < 8) 174 #endif 175 fprintf(f, "#define NO_LONG_LONG\n"); 176 if (a->kind <= 2 && fzcheck()) 177 fprintf(f, "#define Sudden_Underflow\n"); 178 return 0; 179 } 180 fprintf(f, "/* Unknown arithmetic */\n"); 181 return 1; 182 } 183