/* Operations with long integers. | |

Copyright (C) 2006, 2007, 2008 Free Software Foundation, Inc. | |

This file is part of GCC. | |

GCC is free software; you can redistribute it and/or modify it | |

under the terms of the GNU General Public License as published by the | |

Free Software Foundation; either version 3, or (at your option) any | |

later version. | |

GCC is distributed in the hope that it will be useful, but WITHOUT | |

ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |

FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |

for more details. | |

You should have received a copy of the GNU General Public License | |

along with GCC; see the file COPYING3. If not see | |

<http://www.gnu.org/licenses/>. */ | |

#ifndef DOUBLE_INT_H | |

#define DOUBLE_INT_H | |

#ifndef GENERATOR_FILE | |

#include <gmp.h> | |

#endif | |

#include "coretypes.h" | |

/* A large integer is currently represented as a pair of HOST_WIDE_INTs. | |

It therefore represents a number with precision of | |

2 * HOST_BITS_PER_WIDE_INT bits (it is however possible that the | |

internal representation will change, if numbers with greater precision | |

are needed, so the users should not rely on it). The representation does | |

not contain any information about signedness of the represented value, so | |

it can be used to represent both signed and unsigned numbers. For | |

operations where the results depend on signedness (division, comparisons), | |

it must be specified separately. For each such operation, there are three | |

versions of the function -- double_int_op, that takes an extra UNS argument | |

giving the signedness of the values, and double_int_sop and double_int_uop | |

that stand for its specializations for signed and unsigned values. | |

You may also represent with numbers in smaller precision using double_int. | |

You however need to use double_int_ext (that fills in the bits of the | |

number over the prescribed precision with zeros or with the sign bit) before | |

operations that do not perform arithmetics modulo 2^precision (comparisons, | |

division), and possibly before storing the results, if you want to keep | |

them in some canonical form). In general, the signedness of double_int_ext | |

should match the signedness of the operation. | |

??? The components of double_int differ in signedness mostly for | |

historical reasons (they replace an older structure used to represent | |

numbers with precision higher than HOST_WIDE_INT). It might be less | |

confusing to have them both signed or both unsigned. */ | |

typedef struct | |

{ | |

unsigned HOST_WIDE_INT low; | |

HOST_WIDE_INT high; | |

} double_int; | |

union tree_node; | |

/* Constructors and conversions. */ | |

union tree_node *double_int_to_tree (union tree_node *, double_int); | |

bool double_int_fits_to_tree_p (const union tree_node *, double_int); | |

double_int tree_to_double_int (const union tree_node *); | |

/* Constructs double_int from integer CST. The bits over the precision of | |

HOST_WIDE_INT are filled with the sign bit. */ | |

static inline double_int | |

shwi_to_double_int (HOST_WIDE_INT cst) | |

{ | |

double_int r; | |

r.low = (unsigned HOST_WIDE_INT) cst; | |

r.high = cst < 0 ? -1 : 0; | |

return r; | |

} | |

/* Some useful constants. */ | |

#define double_int_minus_one (shwi_to_double_int (-1)) | |

#define double_int_zero (shwi_to_double_int (0)) | |

#define double_int_one (shwi_to_double_int (1)) | |

#define double_int_two (shwi_to_double_int (2)) | |

#define double_int_ten (shwi_to_double_int (10)) | |

/* Constructs double_int from unsigned integer CST. The bits over the | |

precision of HOST_WIDE_INT are filled with zeros. */ | |

static inline double_int | |

uhwi_to_double_int (unsigned HOST_WIDE_INT cst) | |

{ | |

double_int r; | |

r.low = cst; | |

r.high = 0; | |

return r; | |

} | |

/* The following operations perform arithmetics modulo 2^precision, | |

so you do not need to call double_int_ext between them, even if | |

you are representing numbers with precision less than | |

2 * HOST_BITS_PER_WIDE_INT bits. */ | |

double_int double_int_mul (double_int, double_int); | |

double_int double_int_add (double_int, double_int); | |

double_int double_int_neg (double_int); | |

/* You must ensure that double_int_ext is called on the operands | |

of the following operations, if the precision of the numbers | |

is less than 2 * HOST_BITS_PER_WIDE_INT bits. */ | |

bool double_int_fits_in_hwi_p (double_int, bool); | |

bool double_int_fits_in_shwi_p (double_int); | |

bool double_int_fits_in_uhwi_p (double_int); | |

HOST_WIDE_INT double_int_to_shwi (double_int); | |

unsigned HOST_WIDE_INT double_int_to_uhwi (double_int); | |

double_int double_int_div (double_int, double_int, bool, unsigned); | |

double_int double_int_sdiv (double_int, double_int, unsigned); | |

double_int double_int_udiv (double_int, double_int, unsigned); | |

double_int double_int_mod (double_int, double_int, bool, unsigned); | |

double_int double_int_smod (double_int, double_int, unsigned); | |

double_int double_int_umod (double_int, double_int, unsigned); | |

double_int double_int_divmod (double_int, double_int, bool, unsigned, double_int *); | |

double_int double_int_sdivmod (double_int, double_int, unsigned, double_int *); | |

double_int double_int_udivmod (double_int, double_int, unsigned, double_int *); | |

bool double_int_negative_p (double_int); | |

int double_int_cmp (double_int, double_int, bool); | |

int double_int_scmp (double_int, double_int); | |

int double_int_ucmp (double_int, double_int); | |

void dump_double_int (FILE *, double_int, bool); | |

/* Zero and sign extension of numbers in smaller precisions. */ | |

double_int double_int_ext (double_int, unsigned, bool); | |

double_int double_int_sext (double_int, unsigned); | |

double_int double_int_zext (double_int, unsigned); | |

double_int double_int_mask (unsigned); | |

#define ALL_ONES (~((unsigned HOST_WIDE_INT) 0)) | |

/* The operands of the following comparison functions must be processed | |

with double_int_ext, if their precision is less than | |

2 * HOST_BITS_PER_WIDE_INT bits. */ | |

/* Returns true if CST is zero. */ | |

static inline bool | |

double_int_zero_p (double_int cst) | |

{ | |

return cst.low == 0 && cst.high == 0; | |

} | |

/* Returns true if CST is one. */ | |

static inline bool | |

double_int_one_p (double_int cst) | |

{ | |

return cst.low == 1 && cst.high == 0; | |

} | |

/* Returns true if CST is minus one. */ | |

static inline bool | |

double_int_minus_one_p (double_int cst) | |

{ | |

return (cst.low == ALL_ONES && cst.high == -1); | |

} | |

/* Returns true if CST1 == CST2. */ | |

static inline bool | |

double_int_equal_p (double_int cst1, double_int cst2) | |

{ | |

return cst1.low == cst2.low && cst1.high == cst2.high; | |

} | |

#ifndef GENERATOR_FILE | |

/* Conversion to and from GMP integer representations. */ | |

void mpz_set_double_int (mpz_t, double_int, bool); | |

double_int mpz_get_double_int (const_tree, mpz_t, bool); | |

#endif | |

#endif /* DOUBLE_INT_H */ |