1 /* Operations with long integers. 2 Copyright (C) 2006, 2007, 2008, 2010 Free Software Foundation, Inc. 3 4 This file is part of GCC. 5 6 GCC is free software; you can redistribute it and/or modify it 7 under the terms of the GNU General Public License as published by the 8 Free Software Foundation; either version 3, or (at your option) any 9 later version. 10 11 GCC is distributed in the hope that it will be useful, but WITHOUT 12 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with GCC; see the file COPYING3. If not see 18 <http://www.gnu.org/licenses/>. */ 19 20 #ifndef DOUBLE_INT_H 21 #define DOUBLE_INT_H 22 23 #ifndef GENERATOR_FILE 24 #include <gmp.h> 25 #endif 26 #include "coretypes.h" 27 28 /* A large integer is currently represented as a pair of HOST_WIDE_INTs. 29 It therefore represents a number with precision of 30 2 * HOST_BITS_PER_WIDE_INT bits (it is however possible that the 31 internal representation will change, if numbers with greater precision 32 are needed, so the users should not rely on it). The representation does 33 not contain any information about signedness of the represented value, so 34 it can be used to represent both signed and unsigned numbers. For 35 operations where the results depend on signedness (division, comparisons), 36 it must be specified separately. For each such operation, there are three 37 versions of the function -- double_int_op, that takes an extra UNS argument 38 giving the signedness of the values, and double_int_sop and double_int_uop 39 that stand for its specializations for signed and unsigned values. 40 41 You may also represent with numbers in smaller precision using double_int. 42 You however need to use double_int_ext (that fills in the bits of the 43 number over the prescribed precision with zeros or with the sign bit) before 44 operations that do not perform arithmetics modulo 2^precision (comparisons, 45 division), and possibly before storing the results, if you want to keep 46 them in some canonical form). In general, the signedness of double_int_ext 47 should match the signedness of the operation. 48 49 ??? The components of double_int differ in signedness mostly for 50 historical reasons (they replace an older structure used to represent 51 numbers with precision higher than HOST_WIDE_INT). It might be less 52 confusing to have them both signed or both unsigned. */ 53 54 typedef struct 55 { 56 unsigned HOST_WIDE_INT low; 57 HOST_WIDE_INT high; 58 } double_int; 59 60 #define HOST_BITS_PER_DOUBLE_INT (2 * HOST_BITS_PER_WIDE_INT) 61 62 /* Constructors and conversions. */ 63 64 /* Constructs double_int from integer CST. The bits over the precision of 65 HOST_WIDE_INT are filled with the sign bit. */ 66 67 static inline double_int 68 shwi_to_double_int (HOST_WIDE_INT cst) 69 { 70 double_int r; 71 72 r.low = (unsigned HOST_WIDE_INT) cst; 73 r.high = cst < 0 ? -1 : 0; 74 75 return r; 76 } 77 78 /* Some useful constants. */ 79 80 #define double_int_minus_one (shwi_to_double_int (-1)) 81 #define double_int_zero (shwi_to_double_int (0)) 82 #define double_int_one (shwi_to_double_int (1)) 83 #define double_int_two (shwi_to_double_int (2)) 84 #define double_int_ten (shwi_to_double_int (10)) 85 86 /* Constructs double_int from unsigned integer CST. The bits over the 87 precision of HOST_WIDE_INT are filled with zeros. */ 88 89 static inline double_int 90 uhwi_to_double_int (unsigned HOST_WIDE_INT cst) 91 { 92 double_int r; 93 94 r.low = cst; 95 r.high = 0; 96 97 return r; 98 } 99 100 /* Returns value of CST as a signed number. CST must satisfy 101 double_int_fits_in_shwi_p. */ 102 103 static inline HOST_WIDE_INT 104 double_int_to_shwi (double_int cst) 105 { 106 return (HOST_WIDE_INT) cst.low; 107 } 108 109 /* Returns value of CST as an unsigned number. CST must satisfy 110 double_int_fits_in_uhwi_p. */ 111 112 static inline unsigned HOST_WIDE_INT 113 double_int_to_uhwi (double_int cst) 114 { 115 return cst.low; 116 } 117 118 bool double_int_fits_in_hwi_p (double_int, bool); 119 bool double_int_fits_in_shwi_p (double_int); 120 121 /* Returns true if CST fits in unsigned HOST_WIDE_INT. */ 122 123 static inline bool 124 double_int_fits_in_uhwi_p (double_int cst) 125 { 126 return cst.high == 0; 127 } 128 129 /* The following operations perform arithmetics modulo 2^precision, 130 so you do not need to call double_int_ext between them, even if 131 you are representing numbers with precision less than 132 2 * HOST_BITS_PER_WIDE_INT bits. */ 133 134 double_int double_int_mul (double_int, double_int); 135 double_int double_int_mul_with_sign (double_int, double_int, bool, int *); 136 double_int double_int_add (double_int, double_int); 137 double_int double_int_sub (double_int, double_int); 138 double_int double_int_neg (double_int); 139 140 /* You must ensure that double_int_ext is called on the operands 141 of the following operations, if the precision of the numbers 142 is less than 2 * HOST_BITS_PER_WIDE_INT bits. */ 143 double_int double_int_div (double_int, double_int, bool, unsigned); 144 double_int double_int_sdiv (double_int, double_int, unsigned); 145 double_int double_int_udiv (double_int, double_int, unsigned); 146 double_int double_int_mod (double_int, double_int, bool, unsigned); 147 double_int double_int_smod (double_int, double_int, unsigned); 148 double_int double_int_umod (double_int, double_int, unsigned); 149 double_int double_int_divmod (double_int, double_int, bool, unsigned, double_int *); 150 double_int double_int_sdivmod (double_int, double_int, unsigned, double_int *); 151 double_int double_int_udivmod (double_int, double_int, unsigned, double_int *); 152 153 double_int double_int_setbit (double_int, unsigned); 154 int double_int_ctz (double_int); 155 156 /* Logical operations. */ 157 158 /* Returns ~A. */ 159 160 static inline double_int 161 double_int_not (double_int a) 162 { 163 a.low = ~a.low; 164 a.high = ~a.high; 165 return a; 166 } 167 168 /* Returns A | B. */ 169 170 static inline double_int 171 double_int_ior (double_int a, double_int b) 172 { 173 a.low |= b.low; 174 a.high |= b.high; 175 return a; 176 } 177 178 /* Returns A & B. */ 179 180 static inline double_int 181 double_int_and (double_int a, double_int b) 182 { 183 a.low &= b.low; 184 a.high &= b.high; 185 return a; 186 } 187 188 /* Returns A & ~B. */ 189 190 static inline double_int 191 double_int_and_not (double_int a, double_int b) 192 { 193 a.low &= ~b.low; 194 a.high &= ~b.high; 195 return a; 196 } 197 198 /* Returns A ^ B. */ 199 200 static inline double_int 201 double_int_xor (double_int a, double_int b) 202 { 203 a.low ^= b.low; 204 a.high ^= b.high; 205 return a; 206 } 207 208 209 /* Shift operations. */ 210 double_int double_int_lshift (double_int, HOST_WIDE_INT, unsigned int, bool); 211 double_int double_int_rshift (double_int, HOST_WIDE_INT, unsigned int, bool); 212 double_int double_int_lrotate (double_int, HOST_WIDE_INT, unsigned int); 213 double_int double_int_rrotate (double_int, HOST_WIDE_INT, unsigned int); 214 215 /* Returns true if CST is negative. Of course, CST is considered to 216 be signed. */ 217 218 static inline bool 219 double_int_negative_p (double_int cst) 220 { 221 return cst.high < 0; 222 } 223 224 int double_int_cmp (double_int, double_int, bool); 225 int double_int_scmp (double_int, double_int); 226 int double_int_ucmp (double_int, double_int); 227 228 double_int double_int_max (double_int, double_int, bool); 229 double_int double_int_smax (double_int, double_int); 230 double_int double_int_umax (double_int, double_int); 231 232 double_int double_int_min (double_int, double_int, bool); 233 double_int double_int_smin (double_int, double_int); 234 double_int double_int_umin (double_int, double_int); 235 236 void dump_double_int (FILE *, double_int, bool); 237 238 /* Zero and sign extension of numbers in smaller precisions. */ 239 240 double_int double_int_ext (double_int, unsigned, bool); 241 double_int double_int_sext (double_int, unsigned); 242 double_int double_int_zext (double_int, unsigned); 243 double_int double_int_mask (unsigned); 244 245 #define ALL_ONES (~((unsigned HOST_WIDE_INT) 0)) 246 247 /* The operands of the following comparison functions must be processed 248 with double_int_ext, if their precision is less than 249 2 * HOST_BITS_PER_WIDE_INT bits. */ 250 251 /* Returns true if CST is zero. */ 252 253 static inline bool 254 double_int_zero_p (double_int cst) 255 { 256 return cst.low == 0 && cst.high == 0; 257 } 258 259 /* Returns true if CST is one. */ 260 261 static inline bool 262 double_int_one_p (double_int cst) 263 { 264 return cst.low == 1 && cst.high == 0; 265 } 266 267 /* Returns true if CST is minus one. */ 268 269 static inline bool 270 double_int_minus_one_p (double_int cst) 271 { 272 return (cst.low == ALL_ONES && cst.high == -1); 273 } 274 275 /* Returns true if CST1 == CST2. */ 276 277 static inline bool 278 double_int_equal_p (double_int cst1, double_int cst2) 279 { 280 return cst1.low == cst2.low && cst1.high == cst2.high; 281 } 282 283 284 /* Legacy interface with decomposed high/low parts. */ 285 286 extern int add_double_with_sign (unsigned HOST_WIDE_INT, HOST_WIDE_INT, 287 unsigned HOST_WIDE_INT, HOST_WIDE_INT, 288 unsigned HOST_WIDE_INT *, HOST_WIDE_INT *, 289 bool); 290 #define add_double(l1,h1,l2,h2,lv,hv) \ 291 add_double_with_sign (l1, h1, l2, h2, lv, hv, false) 292 extern int neg_double (unsigned HOST_WIDE_INT, HOST_WIDE_INT, 293 unsigned HOST_WIDE_INT *, HOST_WIDE_INT *); 294 extern int mul_double_with_sign (unsigned HOST_WIDE_INT, HOST_WIDE_INT, 295 unsigned HOST_WIDE_INT, HOST_WIDE_INT, 296 unsigned HOST_WIDE_INT *, HOST_WIDE_INT *, 297 bool); 298 #define mul_double(l1,h1,l2,h2,lv,hv) \ 299 mul_double_with_sign (l1, h1, l2, h2, lv, hv, false) 300 extern void lshift_double (unsigned HOST_WIDE_INT, HOST_WIDE_INT, 301 HOST_WIDE_INT, unsigned int, 302 unsigned HOST_WIDE_INT *, HOST_WIDE_INT *, bool); 303 extern void rshift_double (unsigned HOST_WIDE_INT, HOST_WIDE_INT, 304 HOST_WIDE_INT, unsigned int, 305 unsigned HOST_WIDE_INT *, HOST_WIDE_INT *, bool); 306 extern int div_and_round_double (unsigned, int, unsigned HOST_WIDE_INT, 307 HOST_WIDE_INT, unsigned HOST_WIDE_INT, 308 HOST_WIDE_INT, unsigned HOST_WIDE_INT *, 309 HOST_WIDE_INT *, unsigned HOST_WIDE_INT *, 310 HOST_WIDE_INT *); 311 312 313 #ifndef GENERATOR_FILE 314 /* Conversion to and from GMP integer representations. */ 315 316 void mpz_set_double_int (mpz_t, double_int, bool); 317 double_int mpz_get_double_int (const_tree, mpz_t, bool); 318 #endif 319 320 #endif /* DOUBLE_INT_H */ 321