1 /* Operations with long integers.
2 Copyright (C) 2006, 2007, 2008, 2010 Free Software Foundation, Inc.
4 This file is part of GCC.
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
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
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/>. */
23 #ifndef GENERATOR_FILE
26 #include "coretypes.h"
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.
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.
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. */
56 unsigned HOST_WIDE_INT low;
60 #define HOST_BITS_PER_DOUBLE_INT (2 * HOST_BITS_PER_WIDE_INT)
64 /* Constructors and conversions. */
66 /* Constructs double_int from integer CST. The bits over the precision of
67 HOST_WIDE_INT are filled with the sign bit. */
69 static inline double_int
70 shwi_to_double_int (HOST_WIDE_INT cst)
74 r.low = (unsigned HOST_WIDE_INT) cst;
75 r.high = cst < 0 ? -1 : 0;
80 /* Some useful constants. */
82 #define double_int_minus_one (shwi_to_double_int (-1))
83 #define double_int_zero (shwi_to_double_int (0))
84 #define double_int_one (shwi_to_double_int (1))
85 #define double_int_two (shwi_to_double_int (2))
86 #define double_int_ten (shwi_to_double_int (10))
88 /* Constructs double_int from unsigned integer CST. The bits over the
89 precision of HOST_WIDE_INT are filled with zeros. */
91 static inline double_int
92 uhwi_to_double_int (unsigned HOST_WIDE_INT cst)
102 /* The following operations perform arithmetics modulo 2^precision,
103 so you do not need to call double_int_ext between them, even if
104 you are representing numbers with precision less than
105 2 * HOST_BITS_PER_WIDE_INT bits. */
107 double_int double_int_mul (double_int, double_int);
108 double_int double_int_add (double_int, double_int);
109 double_int double_int_neg (double_int);
111 /* You must ensure that double_int_ext is called on the operands
112 of the following operations, if the precision of the numbers
113 is less than 2 * HOST_BITS_PER_WIDE_INT bits. */
114 bool double_int_fits_in_hwi_p (double_int, bool);
115 bool double_int_fits_in_shwi_p (double_int);
116 bool double_int_fits_in_uhwi_p (double_int);
117 HOST_WIDE_INT double_int_to_shwi (double_int);
118 unsigned HOST_WIDE_INT double_int_to_uhwi (double_int);
119 double_int double_int_div (double_int, double_int, bool, unsigned);
120 double_int double_int_sdiv (double_int, double_int, unsigned);
121 double_int double_int_udiv (double_int, double_int, unsigned);
122 double_int double_int_mod (double_int, double_int, bool, unsigned);
123 double_int double_int_smod (double_int, double_int, unsigned);
124 double_int double_int_umod (double_int, double_int, unsigned);
125 double_int double_int_divmod (double_int, double_int, bool, unsigned, double_int *);
126 double_int double_int_sdivmod (double_int, double_int, unsigned, double_int *);
127 double_int double_int_udivmod (double_int, double_int, unsigned, double_int *);
129 /* Logical operations. */
130 static inline double_int
131 double_int_not (double_int a)
138 /* Shift operations. */
139 double_int double_int_lshift (double_int, HOST_WIDE_INT, unsigned int, bool);
140 double_int double_int_rshift (double_int, HOST_WIDE_INT, unsigned int, bool);
142 /* Returns true if CST is negative. Of course, CST is considered to
146 double_int_negative_p (double_int cst)
151 int double_int_cmp (double_int, double_int, bool);
152 int double_int_scmp (double_int, double_int);
153 int double_int_ucmp (double_int, double_int);
154 void dump_double_int (FILE *, double_int, bool);
156 /* Zero and sign extension of numbers in smaller precisions. */
158 double_int double_int_ext (double_int, unsigned, bool);
159 double_int double_int_sext (double_int, unsigned);
160 double_int double_int_zext (double_int, unsigned);
161 double_int double_int_mask (unsigned);
163 #define ALL_ONES (~((unsigned HOST_WIDE_INT) 0))
165 /* The operands of the following comparison functions must be processed
166 with double_int_ext, if their precision is less than
167 2 * HOST_BITS_PER_WIDE_INT bits. */
169 /* Returns true if CST is zero. */
172 double_int_zero_p (double_int cst)
174 return cst.low == 0 && cst.high == 0;
177 /* Returns true if CST is one. */
180 double_int_one_p (double_int cst)
182 return cst.low == 1 && cst.high == 0;
185 /* Returns true if CST is minus one. */
188 double_int_minus_one_p (double_int cst)
190 return (cst.low == ALL_ONES && cst.high == -1);
193 /* Returns true if CST1 == CST2. */
196 double_int_equal_p (double_int cst1, double_int cst2)
198 return cst1.low == cst2.low && cst1.high == cst2.high;
202 /* Legacy interface with decomposed high/low parts. */
204 extern tree force_fit_type_double (tree, unsigned HOST_WIDE_INT, HOST_WIDE_INT,
206 extern int fit_double_type (unsigned HOST_WIDE_INT, HOST_WIDE_INT,
207 unsigned HOST_WIDE_INT *, HOST_WIDE_INT *,
209 extern int add_double_with_sign (unsigned HOST_WIDE_INT, HOST_WIDE_INT,
210 unsigned HOST_WIDE_INT, HOST_WIDE_INT,
211 unsigned HOST_WIDE_INT *, HOST_WIDE_INT *,
213 #define add_double(l1,h1,l2,h2,lv,hv) \
214 add_double_with_sign (l1, h1, l2, h2, lv, hv, false)
215 extern int neg_double (unsigned HOST_WIDE_INT, HOST_WIDE_INT,
216 unsigned HOST_WIDE_INT *, HOST_WIDE_INT *);
217 extern int mul_double_with_sign (unsigned HOST_WIDE_INT, HOST_WIDE_INT,
218 unsigned HOST_WIDE_INT, HOST_WIDE_INT,
219 unsigned HOST_WIDE_INT *, HOST_WIDE_INT *,
221 #define mul_double(l1,h1,l2,h2,lv,hv) \
222 mul_double_with_sign (l1, h1, l2, h2, lv, hv, false)
223 extern void lshift_double (unsigned HOST_WIDE_INT, HOST_WIDE_INT,
224 HOST_WIDE_INT, unsigned int,
225 unsigned HOST_WIDE_INT *, HOST_WIDE_INT *, bool);
226 extern void rshift_double (unsigned HOST_WIDE_INT, HOST_WIDE_INT,
227 HOST_WIDE_INT, unsigned int,
228 unsigned HOST_WIDE_INT *, HOST_WIDE_INT *, bool);
229 extern void lrotate_double (unsigned HOST_WIDE_INT, HOST_WIDE_INT,
230 HOST_WIDE_INT, unsigned int,
231 unsigned HOST_WIDE_INT *, HOST_WIDE_INT *);
232 extern void rrotate_double (unsigned HOST_WIDE_INT, HOST_WIDE_INT,
233 HOST_WIDE_INT, unsigned int,
234 unsigned HOST_WIDE_INT *, HOST_WIDE_INT *);
235 extern int div_and_round_double (unsigned, int, unsigned HOST_WIDE_INT,
236 HOST_WIDE_INT, unsigned HOST_WIDE_INT,
237 HOST_WIDE_INT, unsigned HOST_WIDE_INT *,
238 HOST_WIDE_INT *, unsigned HOST_WIDE_INT *,
242 #ifndef GENERATOR_FILE
243 /* Conversion to and from GMP integer representations. */
245 void mpz_set_double_int (mpz_t, double_int, bool);
246 double_int mpz_get_double_int (const_tree, mpz_t, bool);
249 #endif /* DOUBLE_INT_H */