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/* Operations with long integers.
Copyright (C) 2006-2015 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/>. */
#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "tm.h" /* For BITS_PER_UNIT and *_BIG_ENDIAN. */
#include "hash-set.h"
#include "machmode.h"
#include "vec.h"
#include "double-int.h"
#include "input.h"
#include "alias.h"
#include "symtab.h"
#include "wide-int.h"
#include "inchash.h"
#include "real.h"
#include "tree.h"
static int add_double_with_sign (unsigned HOST_WIDE_INT, HOST_WIDE_INT,
unsigned HOST_WIDE_INT, HOST_WIDE_INT,
unsigned HOST_WIDE_INT *, HOST_WIDE_INT *,
bool);
#define add_double(l1,h1,l2,h2,lv,hv) \
add_double_with_sign (l1, h1, l2, h2, lv, hv, false)
static int neg_double (unsigned HOST_WIDE_INT, HOST_WIDE_INT,
unsigned HOST_WIDE_INT *, HOST_WIDE_INT *);
static int mul_double_wide_with_sign (unsigned HOST_WIDE_INT, HOST_WIDE_INT,
unsigned HOST_WIDE_INT, HOST_WIDE_INT,
unsigned HOST_WIDE_INT *, HOST_WIDE_INT *,
unsigned HOST_WIDE_INT *, HOST_WIDE_INT *,
bool);
#define mul_double(l1,h1,l2,h2,lv,hv) \
mul_double_wide_with_sign (l1, h1, l2, h2, lv, hv, NULL, NULL, false)
static int div_and_round_double (unsigned, int, unsigned HOST_WIDE_INT,
HOST_WIDE_INT, unsigned HOST_WIDE_INT,
HOST_WIDE_INT, unsigned HOST_WIDE_INT *,
HOST_WIDE_INT *, unsigned HOST_WIDE_INT *,
HOST_WIDE_INT *);
/* We know that A1 + B1 = SUM1, using 2's complement arithmetic and ignoring
overflow. Suppose A, B and SUM have the same respective signs as A1, B1,
and SUM1. Then this yields nonzero if overflow occurred during the
addition.
Overflow occurs if A and B have the same sign, but A and SUM differ in
sign. Use `^' to test whether signs differ, and `< 0' to isolate the
sign. */
#define OVERFLOW_SUM_SIGN(a, b, sum) ((~((a) ^ (b)) & ((a) ^ (sum))) < 0)
/* To do constant folding on INTEGER_CST nodes requires two-word arithmetic.
We do that by representing the two-word integer in 4 words, with only
HOST_BITS_PER_WIDE_INT / 2 bits stored in each word, as a positive
number. The value of the word is LOWPART + HIGHPART * BASE. */
#define LOWPART(x) \
((x) & (((unsigned HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2)) - 1))
#define HIGHPART(x) \
((unsigned HOST_WIDE_INT) (x) >> HOST_BITS_PER_WIDE_INT / 2)
#define BASE ((unsigned HOST_WIDE_INT) 1 << HOST_BITS_PER_WIDE_INT / 2)
/* Unpack a two-word integer into 4 words.
LOW and HI are the integer, as two `HOST_WIDE_INT' pieces.
WORDS points to the array of HOST_WIDE_INTs. */
static void
encode (HOST_WIDE_INT *words, unsigned HOST_WIDE_INT low, HOST_WIDE_INT hi)
{
words[0] = LOWPART (low);
words[1] = HIGHPART (low);
words[2] = LOWPART (hi);
words[3] = HIGHPART (hi);
}
/* Pack an array of 4 words into a two-word integer.
WORDS points to the array of words.
The integer is stored into *LOW and *HI as two `HOST_WIDE_INT' pieces. */
static void
decode (HOST_WIDE_INT *words, unsigned HOST_WIDE_INT *low,
HOST_WIDE_INT *hi)
{
*low = words[0] + words[1] * BASE;
*hi = words[2] + words[3] * BASE;
}
/* Add two doubleword integers with doubleword result.
Return nonzero if the operation overflows according to UNSIGNED_P.
Each argument is given as two `HOST_WIDE_INT' pieces.
One argument is L1 and H1; the other, L2 and H2.
The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */
static int
add_double_with_sign (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
unsigned HOST_WIDE_INT l2, HOST_WIDE_INT h2,
unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv,
bool unsigned_p)
{
unsigned HOST_WIDE_INT l;
HOST_WIDE_INT h;
l = l1 + l2;
h = (HOST_WIDE_INT) ((unsigned HOST_WIDE_INT) h1
+ (unsigned HOST_WIDE_INT) h2
+ (l < l1));
*lv = l;
*hv = h;
if (unsigned_p)
return ((unsigned HOST_WIDE_INT) h < (unsigned HOST_WIDE_INT) h1
|| (h == h1
&& l < l1));
else
return OVERFLOW_SUM_SIGN (h1, h2, h);
}
/* Negate a doubleword integer with doubleword result.
Return nonzero if the operation overflows, assuming it's signed.
The argument is given as two `HOST_WIDE_INT' pieces in L1 and H1.
The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */
static int
neg_double (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv)
{
if (l1 == 0)
{
*lv = 0;
*hv = - (unsigned HOST_WIDE_INT) h1;
return (*hv & h1) < 0;
}
else
{
*lv = -l1;
*hv = ~h1;
return 0;
}
}
/* Multiply two doubleword integers with quadword result.
Return nonzero if the operation overflows according to UNSIGNED_P.
Each argument is given as two `HOST_WIDE_INT' pieces.
One argument is L1 and H1; the other, L2 and H2.
The value is stored as four `HOST_WIDE_INT' pieces in *LV and *HV,
*LW and *HW.
If lw is NULL then only the low part and no overflow is computed. */
static int
mul_double_wide_with_sign (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
unsigned HOST_WIDE_INT l2, HOST_WIDE_INT h2,
unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv,
unsigned HOST_WIDE_INT *lw, HOST_WIDE_INT *hw,
bool unsigned_p)
{
HOST_WIDE_INT arg1[4];
HOST_WIDE_INT arg2[4];
HOST_WIDE_INT prod[4 * 2];
unsigned HOST_WIDE_INT carry;
int i, j, k;
unsigned HOST_WIDE_INT neglow;
HOST_WIDE_INT neghigh;
encode (arg1, l1, h1);
encode (arg2, l2, h2);
memset (prod, 0, sizeof prod);
for (i = 0; i < 4; i++)
{
carry = 0;
for (j = 0; j < 4; j++)
{
k = i + j;
/* This product is <= 0xFFFE0001, the sum <= 0xFFFF0000. */
carry += (unsigned HOST_WIDE_INT) arg1[i] * arg2[j];
/* Since prod[p] < 0xFFFF, this sum <= 0xFFFFFFFF. */
carry += prod[k];
prod[k] = LOWPART (carry);
carry = HIGHPART (carry);
}
prod[i + 4] = carry;
}
decode (prod, lv, hv);
/* We are not interested in the wide part nor in overflow. */
if (lw == NULL)
return 0;
decode (prod + 4, lw, hw);
/* Unsigned overflow is immediate. */
if (unsigned_p)
return (*lw | *hw) != 0;
/* Check for signed overflow by calculating the signed representation of the
top half of the result; it should agree with the low half's sign bit. */
if (h1 < 0)
{
neg_double (l2, h2, &neglow, &neghigh);
add_double (neglow, neghigh, *lw, *hw, lw, hw);
}
if (h2 < 0)
{
neg_double (l1, h1, &neglow, &neghigh);
add_double (neglow, neghigh, *lw, *hw, lw, hw);
}
return (*hv < 0 ? ~(*lw & *hw) : *lw | *hw) != 0;
}
/* Shift the doubleword integer in L1, H1 right by COUNT places
keeping only PREC bits of result. ARITH nonzero specifies
arithmetic shifting; otherwise use logical shift.
Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */
static void
rshift_double (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
unsigned HOST_WIDE_INT count, unsigned int prec,
unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv,
bool arith)
{
unsigned HOST_WIDE_INT signmask;
signmask = (arith
? -((unsigned HOST_WIDE_INT) h1 >> (HOST_BITS_PER_WIDE_INT - 1))
: 0);
if (count >= HOST_BITS_PER_DOUBLE_INT)
{
/* Shifting by the host word size is undefined according to the
ANSI standard, so we must handle this as a special case. */
*hv = 0;
*lv = 0;
}
else if (count >= HOST_BITS_PER_WIDE_INT)
{
*hv = 0;
*lv = (unsigned HOST_WIDE_INT) h1 >> (count - HOST_BITS_PER_WIDE_INT);
}
else
{
*hv = (unsigned HOST_WIDE_INT) h1 >> count;
*lv = ((l1 >> count)
| ((unsigned HOST_WIDE_INT) h1
<< (HOST_BITS_PER_WIDE_INT - count - 1) << 1));
}
/* Zero / sign extend all bits that are beyond the precision. */
if (count >= prec)
{
*hv = signmask;
*lv = signmask;
}
else if ((prec - count) >= HOST_BITS_PER_DOUBLE_INT)
;
else if ((prec - count) >= HOST_BITS_PER_WIDE_INT)
{
*hv &= ~(HOST_WIDE_INT_M1U << (prec - count - HOST_BITS_PER_WIDE_INT));
*hv |= signmask << (prec - count - HOST_BITS_PER_WIDE_INT);
}
else
{
*hv = signmask;
*lv &= ~(HOST_WIDE_INT_M1U << (prec - count));
*lv |= signmask << (prec - count);
}
}
/* Shift the doubleword integer in L1, H1 left by COUNT places
keeping only PREC bits of result.
Shift right if COUNT is negative.
ARITH nonzero specifies arithmetic shifting; otherwise use logical shift.
Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */
static void
lshift_double (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
unsigned HOST_WIDE_INT count, unsigned int prec,
unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv)
{
unsigned HOST_WIDE_INT signmask;
if (count >= HOST_BITS_PER_DOUBLE_INT)
{
/* Shifting by the host word size is undefined according to the
ANSI standard, so we must handle this as a special case. */
*hv = 0;
*lv = 0;
}
else if (count >= HOST_BITS_PER_WIDE_INT)
{
*hv = l1 << (count - HOST_BITS_PER_WIDE_INT);
*lv = 0;
}
else
{
*hv = (((unsigned HOST_WIDE_INT) h1 << count)
| (l1 >> (HOST_BITS_PER_WIDE_INT - count - 1) >> 1));
*lv = l1 << count;
}
/* Sign extend all bits that are beyond the precision. */
signmask = -((prec > HOST_BITS_PER_WIDE_INT
? ((unsigned HOST_WIDE_INT) *hv
>> (prec - HOST_BITS_PER_WIDE_INT - 1))
: (*lv >> (prec - 1))) & 1);
if (prec >= HOST_BITS_PER_DOUBLE_INT)
;
else if (prec >= HOST_BITS_PER_WIDE_INT)
{
*hv &= ~(HOST_WIDE_INT_M1U << (prec - HOST_BITS_PER_WIDE_INT));
*hv |= signmask << (prec - HOST_BITS_PER_WIDE_INT);
}
else
{
*hv = signmask;
*lv &= ~(HOST_WIDE_INT_M1U << prec);
*lv |= signmask << prec;
}
}
/* Divide doubleword integer LNUM, HNUM by doubleword integer LDEN, HDEN
for a quotient (stored in *LQUO, *HQUO) and remainder (in *LREM, *HREM).
CODE is a tree code for a kind of division, one of
TRUNC_DIV_EXPR, FLOOR_DIV_EXPR, CEIL_DIV_EXPR, ROUND_DIV_EXPR
or EXACT_DIV_EXPR
It controls how the quotient is rounded to an integer.
Return nonzero if the operation overflows.
UNS nonzero says do unsigned division. */
static int
div_and_round_double (unsigned code, int uns,
/* num == numerator == dividend */
unsigned HOST_WIDE_INT lnum_orig,
HOST_WIDE_INT hnum_orig,
/* den == denominator == divisor */
unsigned HOST_WIDE_INT lden_orig,
HOST_WIDE_INT hden_orig,
unsigned HOST_WIDE_INT *lquo,
HOST_WIDE_INT *hquo, unsigned HOST_WIDE_INT *lrem,
HOST_WIDE_INT *hrem)
{
int quo_neg = 0;
HOST_WIDE_INT num[4 + 1]; /* extra element for scaling. */
HOST_WIDE_INT den[4], quo[4];
int i, j;
unsigned HOST_WIDE_INT work;
unsigned HOST_WIDE_INT carry = 0;
unsigned HOST_WIDE_INT lnum = lnum_orig;
HOST_WIDE_INT hnum = hnum_orig;
unsigned HOST_WIDE_INT lden = lden_orig;
HOST_WIDE_INT hden = hden_orig;
int overflow = 0;
if (hden == 0 && lden == 0)
overflow = 1, lden = 1;
/* Calculate quotient sign and convert operands to unsigned. */
if (!uns)
{
if (hnum < 0)
{
quo_neg = ~ quo_neg;
/* (minimum integer) / (-1) is the only overflow case. */
if (neg_double (lnum, hnum, &lnum, &hnum)
&& ((HOST_WIDE_INT) lden & hden) == -1)
overflow = 1;
}
if (hden < 0)
{
quo_neg = ~ quo_neg;
neg_double (lden, hden, &lden, &hden);
}
}
if (hnum == 0 && hden == 0)
{ /* single precision */
*hquo = *hrem = 0;
/* This unsigned division rounds toward zero. */
*lquo = lnum / lden;
goto finish_up;
}
if (hnum == 0)
{ /* trivial case: dividend < divisor */
/* hden != 0 already checked. */
*hquo = *lquo = 0;
*hrem = hnum;
*lrem = lnum;
goto finish_up;
}
memset (quo, 0, sizeof quo);
memset (num, 0, sizeof num); /* to zero 9th element */
memset (den, 0, sizeof den);
encode (num, lnum, hnum);
encode (den, lden, hden);
/* Special code for when the divisor < BASE. */
if (hden == 0 && lden < (unsigned HOST_WIDE_INT) BASE)
{
/* hnum != 0 already checked. */
for (i = 4 - 1; i >= 0; i--)
{
work = num[i] + carry * BASE;
quo[i] = work / lden;
carry = work % lden;
}
}
else
{
/* Full double precision division,
with thanks to Don Knuth's "Seminumerical Algorithms". */
int num_hi_sig, den_hi_sig;
unsigned HOST_WIDE_INT quo_est, scale;
/* Find the highest nonzero divisor digit. */
for (i = 4 - 1;; i--)
if (den[i] != 0)
{
den_hi_sig = i;
break;
}
/* Insure that the first digit of the divisor is at least BASE/2.
This is required by the quotient digit estimation algorithm. */
scale = BASE / (den[den_hi_sig] + 1);
if (scale > 1)
{ /* scale divisor and dividend */
carry = 0;
for (i = 0; i <= 4 - 1; i++)
{
work = (num[i] * scale) + carry;
num[i] = LOWPART (work);
carry = HIGHPART (work);
}
num[4] = carry;
carry = 0;
for (i = 0; i <= 4 - 1; i++)
{
work = (den[i] * scale) + carry;
den[i] = LOWPART (work);
carry = HIGHPART (work);
if (den[i] != 0) den_hi_sig = i;
}
}
num_hi_sig = 4;
/* Main loop */
for (i = num_hi_sig - den_hi_sig - 1; i >= 0; i--)
{
/* Guess the next quotient digit, quo_est, by dividing the first
two remaining dividend digits by the high order quotient digit.
quo_est is never low and is at most 2 high. */
unsigned HOST_WIDE_INT tmp;
num_hi_sig = i + den_hi_sig + 1;
work = num[num_hi_sig] * BASE + num[num_hi_sig - 1];
if (num[num_hi_sig] != den[den_hi_sig])
quo_est = work / den[den_hi_sig];
else
quo_est = BASE - 1;
/* Refine quo_est so it's usually correct, and at most one high. */
tmp = work - quo_est * den[den_hi_sig];
if (tmp < BASE
&& (den[den_hi_sig - 1] * quo_est
> (tmp * BASE + num[num_hi_sig - 2])))
quo_est--;
/* Try QUO_EST as the quotient digit, by multiplying the
divisor by QUO_EST and subtracting from the remaining dividend.
Keep in mind that QUO_EST is the I - 1st digit. */
carry = 0;
for (j = 0; j <= den_hi_sig; j++)
{
work = quo_est * den[j] + carry;
carry = HIGHPART (work);
work = num[i + j] - LOWPART (work);
num[i + j] = LOWPART (work);
carry += HIGHPART (work) != 0;
}
/* If quo_est was high by one, then num[i] went negative and
we need to correct things. */
if (num[num_hi_sig] < (HOST_WIDE_INT) carry)
{
quo_est--;
carry = 0; /* add divisor back in */
for (j = 0; j <= den_hi_sig; j++)
{
work = num[i + j] + den[j] + carry;
carry = HIGHPART (work);
num[i + j] = LOWPART (work);
}
num [num_hi_sig] += carry;
}
/* Store the quotient digit. */
quo[i] = quo_est;
}
}
decode (quo, lquo, hquo);
finish_up:
/* If result is negative, make it so. */
if (quo_neg)
neg_double (*lquo, *hquo, lquo, hquo);
/* Compute trial remainder: rem = num - (quo * den) */
mul_double (*lquo, *hquo, lden_orig, hden_orig, lrem, hrem);
neg_double (*lrem, *hrem, lrem, hrem);
add_double (lnum_orig, hnum_orig, *lrem, *hrem, lrem, hrem);
switch (code)
{
case TRUNC_DIV_EXPR:
case TRUNC_MOD_EXPR: /* round toward zero */
case EXACT_DIV_EXPR: /* for this one, it shouldn't matter */
return overflow;
case FLOOR_DIV_EXPR:
case FLOOR_MOD_EXPR: /* round toward negative infinity */
if (quo_neg && (*lrem != 0 || *hrem != 0)) /* ratio < 0 && rem != 0 */
{
/* quo = quo - 1; */
add_double (*lquo, *hquo, (HOST_WIDE_INT) -1, (HOST_WIDE_INT) -1,
lquo, hquo);
}
else
return overflow;
break;
case CEIL_DIV_EXPR:
case CEIL_MOD_EXPR: /* round toward positive infinity */
if (!quo_neg && (*lrem != 0 || *hrem != 0)) /* ratio > 0 && rem != 0 */
{
add_double (*lquo, *hquo, (HOST_WIDE_INT) 1, (HOST_WIDE_INT) 0,
lquo, hquo);
}
else
return overflow;
break;
case ROUND_DIV_EXPR:
case ROUND_MOD_EXPR: /* round to closest integer */
{
unsigned HOST_WIDE_INT labs_rem = *lrem;
HOST_WIDE_INT habs_rem = *hrem;
unsigned HOST_WIDE_INT labs_den = lden, lnegabs_rem, ldiff;
HOST_WIDE_INT habs_den = hden, hnegabs_rem, hdiff;
/* Get absolute values. */
if (!uns && *hrem < 0)
neg_double (*lrem, *hrem, &labs_rem, &habs_rem);
if (!uns && hden < 0)
neg_double (lden, hden, &labs_den, &habs_den);
/* If abs(rem) >= abs(den) - abs(rem), adjust the quotient. */
neg_double (labs_rem, habs_rem, &lnegabs_rem, &hnegabs_rem);
add_double (labs_den, habs_den, lnegabs_rem, hnegabs_rem,
&ldiff, &hdiff);
if (((unsigned HOST_WIDE_INT) habs_rem
> (unsigned HOST_WIDE_INT) hdiff)
|| (habs_rem == hdiff && labs_rem >= ldiff))
{
if (quo_neg)
/* quo = quo - 1; */
add_double (*lquo, *hquo,
(HOST_WIDE_INT) -1, (HOST_WIDE_INT) -1, lquo, hquo);
else
/* quo = quo + 1; */
add_double (*lquo, *hquo, (HOST_WIDE_INT) 1, (HOST_WIDE_INT) 0,
lquo, hquo);
}
else
return overflow;
}
break;
default:
gcc_unreachable ();
}
/* Compute true remainder: rem = num - (quo * den) */
mul_double (*lquo, *hquo, lden_orig, hden_orig, lrem, hrem);
neg_double (*lrem, *hrem, lrem, hrem);
add_double (lnum_orig, hnum_orig, *lrem, *hrem, lrem, hrem);
return overflow;
}
/* Construct from a buffer of length LEN. BUFFER will be read according
to byte endianess and word endianess. Only the lower LEN bytes
of the result are set; the remaining high bytes are cleared. */
double_int
double_int::from_buffer (const unsigned char *buffer, int len)
{
double_int result = double_int_zero;
int words = len / UNITS_PER_WORD;
gcc_assert (len * BITS_PER_UNIT <= HOST_BITS_PER_DOUBLE_INT);
for (int byte = 0; byte < len; byte++)
{
int offset;
int bitpos = byte * BITS_PER_UNIT;
unsigned HOST_WIDE_INT value;
if (len > UNITS_PER_WORD)
{
int word = byte / UNITS_PER_WORD;
if (WORDS_BIG_ENDIAN)
word = (words - 1) - word;
offset = word * UNITS_PER_WORD;
if (BYTES_BIG_ENDIAN)
offset += (UNITS_PER_WORD - 1) - (byte % UNITS_PER_WORD);
else
offset += byte % UNITS_PER_WORD;
}
else
offset = BYTES_BIG_ENDIAN ? (len - 1) - byte : byte;
value = (unsigned HOST_WIDE_INT) buffer[offset];
if (bitpos < HOST_BITS_PER_WIDE_INT)
result.low |= value << bitpos;
else
result.high |= value << (bitpos - HOST_BITS_PER_WIDE_INT);
}
return result;
}
/* Returns mask for PREC bits. */
double_int
double_int::mask (unsigned prec)
{
unsigned HOST_WIDE_INT m;
double_int mask;
if (prec > HOST_BITS_PER_WIDE_INT)
{
prec -= HOST_BITS_PER_WIDE_INT;
m = ((unsigned HOST_WIDE_INT) 2 << (prec - 1)) - 1;
mask.high = (HOST_WIDE_INT) m;
mask.low = ALL_ONES;
}
else
{
mask.high = 0;
mask.low = prec ? ((unsigned HOST_WIDE_INT) 2 << (prec - 1)) - 1 : 0;
}
return mask;
}
/* Returns a maximum value for signed or unsigned integer
of precision PREC. */
double_int
double_int::max_value (unsigned int prec, bool uns)
{
return double_int::mask (prec - (uns ? 0 : 1));
}
/* Returns a minimum value for signed or unsigned integer
of precision PREC. */
double_int
double_int::min_value (unsigned int prec, bool uns)
{
if (uns)
return double_int_zero;
return double_int_one.lshift (prec - 1, prec, false);
}
/* Clears the bits of CST over the precision PREC. If UNS is false, the bits
outside of the precision are set to the sign bit (i.e., the PREC-th one),
otherwise they are set to zero.
This corresponds to returning the value represented by PREC lowermost bits
of CST, with the given signedness. */
double_int
double_int::ext (unsigned prec, bool uns) const
{
if (uns)
return this->zext (prec);
else
return this->sext (prec);
}
/* The same as double_int::ext with UNS = true. */
double_int
double_int::zext (unsigned prec) const
{
const double_int &cst = *this;
double_int mask = double_int::mask (prec);
double_int r;
r.low = cst.low & mask.low;
r.high = cst.high & mask.high;
return r;
}
/* The same as double_int::ext with UNS = false. */
double_int
double_int::sext (unsigned prec) const
{
const double_int &cst = *this;
double_int mask = double_int::mask (prec);
double_int r;
unsigned HOST_WIDE_INT snum;
if (prec <= HOST_BITS_PER_WIDE_INT)
snum = cst.low;
else
{
prec -= HOST_BITS_PER_WIDE_INT;
snum = (unsigned HOST_WIDE_INT) cst.high;
}
if (((snum >> (prec - 1)) & 1) == 1)
{
r.low = cst.low | ~mask.low;
r.high = cst.high | ~mask.high;
}
else
{
r.low = cst.low & mask.low;
r.high = cst.high & mask.high;
}
return r;
}
/* Returns true if CST fits in signed HOST_WIDE_INT. */
bool
double_int::fits_shwi () const
{
const double_int &cst = *this;
if (cst.high == 0)
return (HOST_WIDE_INT) cst.low >= 0;
else if (cst.high == -1)
return (HOST_WIDE_INT) cst.low < 0;
else
return false;
}
/* Returns true if CST fits in HOST_WIDE_INT if UNS is false, or in
unsigned HOST_WIDE_INT if UNS is true. */
bool
double_int::fits_hwi (bool uns) const
{
if (uns)
return this->fits_uhwi ();
else
return this->fits_shwi ();
}
/* Returns A * B. */
double_int
double_int::operator * (double_int b) const
{
const double_int &a = *this;
double_int ret;
mul_double (a.low, a.high, b.low, b.high, &ret.low, &ret.high);
return ret;
}
/* Multiplies *this with B and returns a reference to *this. */
double_int &
double_int::operator *= (double_int b)
{
mul_double (low, high, b.low, b.high, &low, &high);
return *this;
}
/* Returns A * B. If the operation overflows according to UNSIGNED_P,
*OVERFLOW is set to nonzero. */
double_int
double_int::mul_with_sign (double_int b, bool unsigned_p, bool *overflow) const
{
const double_int &a = *this;
double_int ret, tem;
*overflow = mul_double_wide_with_sign (a.low, a.high, b.low, b.high,
&ret.low, &ret.high,
&tem.low, &tem.high, unsigned_p);
return ret;
}
double_int
double_int::wide_mul_with_sign (double_int b, bool unsigned_p,
double_int *higher, bool *overflow) const
{
double_int lower;
*overflow = mul_double_wide_with_sign (low, high, b.low, b.high,
&lower.low, &lower.high,
&higher->low, &higher->high,
unsigned_p);
return lower;
}
/* Returns A + B. */
double_int
double_int::operator + (double_int b) const
{
const double_int &a = *this;
double_int ret;
add_double (a.low, a.high, b.low, b.high, &ret.low, &ret.high);
return ret;
}
/* Adds B to *this and returns a reference to *this. */
double_int &
double_int::operator += (double_int b)
{
add_double (low, high, b.low, b.high, &low, &high);
return *this;
}
/* Returns A + B. If the operation overflows according to UNSIGNED_P,
*OVERFLOW is set to nonzero. */
double_int
double_int::add_with_sign (double_int b, bool unsigned_p, bool *overflow) const
{
const double_int &a = *this;
double_int ret;
*overflow = add_double_with_sign (a.low, a.high, b.low, b.high,
&ret.low, &ret.high, unsigned_p);
return ret;
}
/* Returns A - B. */
double_int
double_int::operator - (double_int b) const
{
const double_int &a = *this;
double_int ret;
neg_double (b.low, b.high, &b.low, &b.high);
add_double (a.low, a.high, b.low, b.high, &ret.low, &ret.high);
return ret;
}
/* Subtracts B from *this and returns a reference to *this. */
double_int &
double_int::operator -= (double_int b)
{
neg_double (b.low, b.high, &b.low, &b.high);
add_double (low, high, b.low, b.high, &low, &high);
return *this;
}
/* Returns A - B. If the operation overflows via inconsistent sign bits,
*OVERFLOW is set to nonzero. */
double_int
double_int::sub_with_overflow (double_int b, bool *overflow) const
{
double_int ret;
neg_double (b.low, b.high, &ret.low, &ret.high);
add_double (low, high, ret.low, ret.high, &ret.low, &ret.high);
*overflow = OVERFLOW_SUM_SIGN (ret.high, b.high, high);
return ret;
}
/* Returns -A. */
double_int
double_int::operator - () const
{
const double_int &a = *this;
double_int ret;
neg_double (a.low, a.high, &ret.low, &ret.high);
return ret;
}
double_int
double_int::neg_with_overflow (bool *overflow) const
{
double_int ret;
*overflow = neg_double (low, high, &ret.low, &ret.high);
return ret;
}
/* Returns A / B (computed as unsigned depending on UNS, and rounded as
specified by CODE). CODE is enum tree_code in fact, but double_int.h
must be included before tree.h. The remainder after the division is
stored to MOD. */
double_int
double_int::divmod_with_overflow (double_int b, bool uns, unsigned code,
double_int *mod, bool *overflow) const
{
const double_int &a = *this;
double_int ret;
*overflow = div_and_round_double (code, uns, a.low, a.high,
b.low, b.high, &ret.low, &ret.high,
&mod->low, &mod->high);
return ret;
}
double_int
double_int::divmod (double_int b, bool uns, unsigned code,
double_int *mod) const
{
const double_int &a = *this;
double_int ret;
div_and_round_double (code, uns, a.low, a.high,
b.low, b.high, &ret.low, &ret.high,
&mod->low, &mod->high);
return ret;
}
/* The same as double_int::divmod with UNS = false. */
double_int
double_int::sdivmod (double_int b, unsigned code, double_int *mod) const
{
return this->divmod (b, false, code, mod);
}
/* The same as double_int::divmod with UNS = true. */
double_int
double_int::udivmod (double_int b, unsigned code, double_int *mod) const
{
return this->divmod (b, true, code, mod);
}
/* Returns A / B (computed as unsigned depending on UNS, and rounded as
specified by CODE). CODE is enum tree_code in fact, but double_int.h
must be included before tree.h. */
double_int
double_int::div (double_int b, bool uns, unsigned code) const
{
double_int mod;
return this->divmod (b, uns, code, &mod);
}
/* The same as double_int::div with UNS = false. */
double_int
double_int::sdiv (double_int b, unsigned code) const
{
return this->div (b, false, code);
}
/* The same as double_int::div with UNS = true. */
double_int
double_int::udiv (double_int b, unsigned code) const
{
return this->div (b, true, code);
}
/* Returns A % B (computed as unsigned depending on UNS, and rounded as
specified by CODE). CODE is enum tree_code in fact, but double_int.h
must be included before tree.h. */
double_int
double_int::mod (double_int b, bool uns, unsigned code) const
{
double_int mod;
this->divmod (b, uns, code, &mod);
return mod;
}
/* The same as double_int::mod with UNS = false. */
double_int
double_int::smod (double_int b, unsigned code) const
{
return this->mod (b, false, code);
}
/* The same as double_int::mod with UNS = true. */
double_int
double_int::umod (double_int b, unsigned code) const
{
return this->mod (b, true, code);
}
/* Return TRUE iff PRODUCT is an integral multiple of FACTOR, and return
the multiple in *MULTIPLE. Otherwise return FALSE and leave *MULTIPLE
unchanged. */
bool
double_int::multiple_of (double_int factor,
bool unsigned_p, double_int *multiple) const
{
double_int remainder;
double_int quotient = this->divmod (factor, unsigned_p,
TRUNC_DIV_EXPR, &remainder);
if (remainder.is_zero ())
{
*multiple = quotient;
return true;
}
return false;
}
/* Set BITPOS bit in A. */
double_int
double_int::set_bit (unsigned bitpos) const
{
double_int a = *this;
if (bitpos < HOST_BITS_PER_WIDE_INT)
a.low |= (unsigned HOST_WIDE_INT) 1 << bitpos;
else
a.high |= (HOST_WIDE_INT) 1 << (bitpos - HOST_BITS_PER_WIDE_INT);
return a;
}
/* Count trailing zeros in A. */
int
double_int::trailing_zeros () const
{
const double_int &a = *this;
unsigned HOST_WIDE_INT w = a.low ? a.low : (unsigned HOST_WIDE_INT) a.high;
unsigned bits = a.low ? 0 : HOST_BITS_PER_WIDE_INT;
if (!w)
return HOST_BITS_PER_DOUBLE_INT;
bits += ctz_hwi (w);
return bits;
}
/* Shift A left by COUNT places. */
double_int
double_int::lshift (HOST_WIDE_INT count) const
{
double_int ret;
gcc_checking_assert (count >= 0);
if (count >= HOST_BITS_PER_DOUBLE_INT)
{
/* Shifting by the host word size is undefined according to the
ANSI standard, so we must handle this as a special case. */
ret.high = 0;
ret.low = 0;
}
else if (count >= HOST_BITS_PER_WIDE_INT)
{
ret.high = low << (count - HOST_BITS_PER_WIDE_INT);
ret.low = 0;
}
else
{
ret.high = (((unsigned HOST_WIDE_INT) high << count)
| (low >> (HOST_BITS_PER_WIDE_INT - count - 1) >> 1));
ret.low = low << count;
}
return ret;
}
/* Shift A right by COUNT places. */
double_int
double_int::rshift (HOST_WIDE_INT count) const
{
double_int ret;
gcc_checking_assert (count >= 0);
if (count >= HOST_BITS_PER_DOUBLE_INT)
{
/* Shifting by the host word size is undefined according to the
ANSI standard, so we must handle this as a special case. */
ret.high = 0;
ret.low = 0;
}
else if (count >= HOST_BITS_PER_WIDE_INT)
{
ret.high = 0;
ret.low
= (unsigned HOST_WIDE_INT) (high >> (count - HOST_BITS_PER_WIDE_INT));
}
else
{
ret.high = high >> count;
ret.low = ((low >> count)
| ((unsigned HOST_WIDE_INT) high
<< (HOST_BITS_PER_WIDE_INT - count - 1) << 1));
}
return ret;
}
/* Shift A left by COUNT places keeping only PREC bits of result. Shift
right if COUNT is negative. ARITH true specifies arithmetic shifting;
otherwise use logical shift. */
double_int
double_int::lshift (HOST_WIDE_INT count, unsigned int prec, bool arith) const
{
double_int ret;
if (count > 0)
lshift_double (low, high, count, prec, &ret.low, &ret.high);
else
rshift_double (low, high, absu_hwi (count), prec, &ret.low, &ret.high, arith);
return ret;
}
/* Shift A right by COUNT places keeping only PREC bits of result. Shift
left if COUNT is negative. ARITH true specifies arithmetic shifting;
otherwise use logical shift. */
double_int
double_int::rshift (HOST_WIDE_INT count, unsigned int prec, bool arith) const
{
double_int ret;
if (count > 0)
rshift_double (low, high, count, prec, &ret.low, &ret.high, arith);
else
lshift_double (low, high, absu_hwi (count), prec, &ret.low, &ret.high);
return ret;
}
/* Arithmetic shift A left by COUNT places keeping only PREC bits of result.
Shift right if COUNT is negative. */
double_int
double_int::alshift (HOST_WIDE_INT count, unsigned int prec) const
{
double_int r;
if (count > 0)
lshift_double (low, high, count, prec, &r.low, &r.high);
else
rshift_double (low, high, absu_hwi (count), prec, &r.low, &r.high, true);
return r;
}
/* Arithmetic shift A right by COUNT places keeping only PREC bits of result.
Shift left if COUNT is negative. */
double_int
double_int::arshift (HOST_WIDE_INT count, unsigned int prec) const
{
double_int r;
if (count > 0)
rshift_double (low, high, count, prec, &r.low, &r.high, true);
else
lshift_double (low, high, absu_hwi (count), prec, &r.low, &r.high);
return r;
}
/* Logical shift A left by COUNT places keeping only PREC bits of result.
Shift right if COUNT is negative. */
double_int
double_int::llshift (HOST_WIDE_INT count, unsigned int prec) const
{
double_int r;
if (count > 0)
lshift_double (low, high, count, prec, &r.low, &r.high);
else
rshift_double (low, high, absu_hwi (count), prec, &r.low, &r.high, false);
return r;
}
/* Logical shift A right by COUNT places keeping only PREC bits of result.
Shift left if COUNT is negative. */
double_int
double_int::lrshift (HOST_WIDE_INT count, unsigned int prec) const
{
double_int r;
if (count > 0)
rshift_double (low, high, count, prec, &r.low, &r.high, false);
else
lshift_double (low, high, absu_hwi (count), prec, &r.low, &r.high);
return r;
}
/* Rotate A left by COUNT places keeping only PREC bits of result.
Rotate right if COUNT is negative. */
double_int
double_int::lrotate (HOST_WIDE_INT count, unsigned int prec) const
{
double_int t1, t2;
count %= prec;
if (count < 0)
count += prec;
t1 = this->llshift (count, prec);
t2 = this->lrshift (prec - count, prec);
return t1 | t2;
}
/* Rotate A rigth by COUNT places keeping only PREC bits of result.
Rotate right if COUNT is negative. */
double_int
double_int::rrotate (HOST_WIDE_INT count, unsigned int prec) const
{
double_int t1, t2;
count %= prec;
if (count < 0)
count += prec;
t1 = this->lrshift (count, prec);
t2 = this->llshift (prec - count, prec);
return t1 | t2;
}
/* Returns -1 if A < B, 0 if A == B and 1 if A > B. Signedness of the
comparison is given by UNS. */
int
double_int::cmp (double_int b, bool uns) const
{
if (uns)
return this->ucmp (b);
else
return this->scmp (b);
}
/* Compares two unsigned values A and B. Returns -1 if A < B, 0 if A == B,
and 1 if A > B. */
int
double_int::ucmp (double_int b) const
{
const double_int &a = *this;
if ((unsigned HOST_WIDE_INT) a.high < (unsigned HOST_WIDE_INT) b.high)
return -1;
if ((unsigned HOST_WIDE_INT) a.high > (unsigned HOST_WIDE_INT) b.high)
return 1;
if (a.low < b.low)
return -1;
if (a.low > b.low)
return 1;
return 0;
}
/* Compares two signed values A and B. Returns -1 if A < B, 0 if A == B,
and 1 if A > B. */
int
double_int::scmp (double_int b) const
{
const double_int &a = *this;
if (a.high < b.high)
return -1;
if (a.high > b.high)
return 1;
if (a.low < b.low)
return -1;
if (a.low > b.low)
return 1;
return 0;
}
/* Compares two unsigned values A and B for less-than. */
bool
double_int::ult (double_int b) const
{
if ((unsigned HOST_WIDE_INT) high < (unsigned HOST_WIDE_INT) b.high)
return true;
if ((unsigned HOST_WIDE_INT) high > (unsigned HOST_WIDE_INT) b.high)
return false;
if (low < b.low)
return true;
return false;
}
/* Compares two unsigned values A and B for less-than or equal-to. */
bool
double_int::ule (double_int b) const
{
if ((unsigned HOST_WIDE_INT) high < (unsigned HOST_WIDE_INT) b.high)
return true;
if ((unsigned HOST_WIDE_INT) high > (unsigned HOST_WIDE_INT) b.high)
return false;
if (low <= b.low)
return true;
return false;
}
/* Compares two unsigned values A and B for greater-than. */
bool
double_int::ugt (double_int b) const
{
if ((unsigned HOST_WIDE_INT) high > (unsigned HOST_WIDE_INT) b.high)
return true;
if ((unsigned HOST_WIDE_INT) high < (unsigned HOST_WIDE_INT) b.high)
return false;
if (low > b.low)
return true;
return false;
}
/* Compares two signed values A and B for less-than. */
bool
double_int::slt (double_int b) const
{
if (high < b.high)
return true;
if (high > b.high)
return false;
if (low < b.low)
return true;
return false;
}
/* Compares two signed values A and B for less-than or equal-to. */
bool
double_int::sle (double_int b) const
{
if (high < b.high)
return true;
if (high > b.high)
return false;
if (low <= b.low)
return true;
return false;
}
/* Compares two signed values A and B for greater-than. */
bool
double_int::sgt (double_int b) const
{
if (high > b.high)
return true;
if (high < b.high)
return false;
if (low > b.low)
return true;
return false;
}
/* Compares two values A and B. Returns max value. Signedness of the
comparison is given by UNS. */
double_int
double_int::max (double_int b, bool uns)
{
return (this->cmp (b, uns) == 1) ? *this : b;
}
/* Compares two signed values A and B. Returns max value. */
double_int
double_int::smax (double_int b)
{
return (this->scmp (b) == 1) ? *this : b;
}
/* Compares two unsigned values A and B. Returns max value. */
double_int
double_int::umax (double_int b)
{
return (this->ucmp (b) == 1) ? *this : b;
}
/* Compares two values A and B. Returns mix value. Signedness of the
comparison is given by UNS. */
double_int
double_int::min (double_int b, bool uns)
{
return (this->cmp (b, uns) == -1) ? *this : b;
}
/* Compares two signed values A and B. Returns min value. */
double_int
double_int::smin (double_int b)
{
return (this->scmp (b) == -1) ? *this : b;
}
/* Compares two unsigned values A and B. Returns min value. */
double_int
double_int::umin (double_int b)
{
return (this->ucmp (b) == -1) ? *this : b;
}
/* Splits last digit of *CST (taken as unsigned) in BASE and returns it. */
static unsigned
double_int_split_digit (double_int *cst, unsigned base)
{
unsigned HOST_WIDE_INT resl, reml;
HOST_WIDE_INT resh, remh;
div_and_round_double (FLOOR_DIV_EXPR, true, cst->low, cst->high, base, 0,
&resl, &resh, &reml, &remh);
cst->high = resh;
cst->low = resl;
return reml;
}
/* Dumps CST to FILE. If UNS is true, CST is considered to be unsigned,
otherwise it is signed. */
void
dump_double_int (FILE *file, double_int cst, bool uns)
{
unsigned digits[100], n;
int i;
if (cst.is_zero ())
{
fprintf (file, "0");
return;
}
if (!uns && cst.is_negative ())
{
fprintf (file, "-");
cst = -cst;
}
for (n = 0; !cst.is_zero (); n++)
digits[n] = double_int_split_digit (&cst, 10);
for (i = n - 1; i >= 0; i--)
fprintf (file, "%u", digits[i]);
}
/* Sets RESULT to VAL, taken unsigned if UNS is true and as signed
otherwise. */
void
mpz_set_double_int (mpz_t result, double_int val, bool uns)
{
bool negate = false;
unsigned HOST_WIDE_INT vp[2];
if (!uns && val.is_negative ())
{
negate = true;
val = -val;
}
vp[0] = val.low;
vp[1] = (unsigned HOST_WIDE_INT) val.high;
mpz_import (result, 2, -1, sizeof (HOST_WIDE_INT), 0, 0, vp);
if (negate)
mpz_neg (result, result);
}
/* Returns VAL converted to TYPE. If WRAP is true, then out-of-range
values of VAL will be wrapped; otherwise, they will be set to the
appropriate minimum or maximum TYPE bound. */
double_int
mpz_get_double_int (const_tree type, mpz_t val, bool wrap)
{
unsigned HOST_WIDE_INT *vp;
size_t count, numb;
double_int res;
if (!wrap)
{
mpz_t min, max;
mpz_init (min);
mpz_init (max);
get_type_static_bounds (type, min, max);
if (mpz_cmp (val, min) < 0)
mpz_set (val, min);
else if (mpz_cmp (val, max) > 0)
mpz_set (val, max);
mpz_clear (min);
mpz_clear (max);
}
/* Determine the number of unsigned HOST_WIDE_INT that are required
for representing the value. The code to calculate count is
extracted from the GMP manual, section "Integer Import and Export":
http://gmplib.org/manual/Integer-Import-and-Export.html */
numb = 8 * sizeof (HOST_WIDE_INT);
count = (mpz_sizeinbase (val, 2) + numb-1) / numb;
if (count < 2)
count = 2;
vp = (unsigned HOST_WIDE_INT *) alloca (count * sizeof (HOST_WIDE_INT));
vp[0] = 0;
vp[1] = 0;
mpz_export (vp, &count, -1, sizeof (HOST_WIDE_INT), 0, 0, val);
gcc_assert (wrap || count <= 2);
res.low = vp[0];
res.high = (HOST_WIDE_INT) vp[1];
res = res.ext (TYPE_PRECISION (type), TYPE_UNSIGNED (type));
if (mpz_sgn (val) < 0)
res = -res;
return res;
}