1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
/*
Copyright (C) 2018 Daniel Schultz
This file is part of FLINT.
FLINT is free software: you can redistribute it and/or modify it under
the terms of the GNU Lesser General Public License (LGPL) as published
by the Free Software Foundation; either version 3 of the License, or
(at your option) any later version. See <https://www.gnu.org/licenses/>.
*/
#include "mpoly.h"
/* !!! this file DOES need to change with new orderings */
int mpoly_monomial_cmp_general(ulong * Aexp, flint_bitcnt_t Abits,
ulong * Bexp, flint_bitcnt_t Bbits, const mpoly_ctx_t mctx)
{
slong N;
if (Abits == Bbits)
{
/* common case */
N = mpoly_words_per_exp(Abits, mctx);
if (!mctx->rev)
{
/* ORD_DEGREVLEX and ORD_DEG_LEX */
return mpoly_monomial_cmp_nomask(Aexp, Bexp, N);
}
else
{
/* ORD_DEGREVLEX */
slong i = N - 1;
if (Abits <= FLINT_BITS)
{
/* compare the highest word */
ulong fpw = FLINT_BITS/Abits;
ulong himask = (UWORD(1) << (mctx->nvars%fpw*Abits)) - UWORD(1);
if (Aexp[i] != Bexp[i])
{
if ((Aexp[i]^himask) > (Bexp[i]^himask))
return 1;
else
return -1;
}
i--;
}
else
{
/* compare the degree field with usual comparison */
ulong wpf = Abits/FLINT_BITS;
do
{
if (Aexp[i] != Bexp[i])
{
if (Aexp[i] > Bexp[i])
return 1;
else
return -1;
}
i--;
} while (--wpf != 0);
}
/* compare the remaining fields with reversed comparisons */
for (; i >= 0; i--)
{
if (Aexp[i] != Bexp[i])
{
if (Aexp[i] < Bexp[i])
return 1;
else
return -1;
}
}
return 0;
}
}
else
{
int cmp;
flint_bitcnt_t newbits;
ulong * newAexp, * newBexp, * cmpmask;
TMP_INIT;
TMP_START;
if (Abits > Bbits)
{
newbits = Abits;
N = mpoly_words_per_exp(newbits, mctx);
newAexp = Aexp;
newBexp = (ulong *) TMP_ALLOC(N*sizeof(ulong));
mpoly_repack_monomials(newBexp, newbits, Bexp, Bbits, 1, mctx);
}
else
{
FLINT_ASSERT(Abits < Bbits);
newbits = Bbits;
N = mpoly_words_per_exp(newbits, mctx);
newBexp = Bexp;
newAexp = (ulong *) TMP_ALLOC(N*sizeof(ulong));
mpoly_repack_monomials(newAexp, newbits, Aexp, Abits, 1, mctx);
}
cmpmask = (ulong *) TMP_ALLOC(N*sizeof(ulong));
mpoly_get_cmpmask(cmpmask, N, newbits, mctx);
cmp = mpoly_monomial_cmp(newAexp, newBexp, N, cmpmask);
TMP_END;
return cmp;
}
}