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
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
|
#
#
# The Nimrod Compiler
# (c) Copyright 2009 Andreas Rumpf
#
# See the file "copying.txt", included in this
# distribution, for details about the copyright.
#
# this unit handles Nimrod sets; it implements symbolic sets
import
ast, astalgo, trees, nversion, msgs, platform, bitsets, types, rnimsyn
proc toBitSet*(s: PNode, b: var TBitSet)
# this function is used for case statement checking:
proc overlap*(a, b: PNode): bool
proc inSet*(s: PNode, elem: PNode): bool
proc someInSet*(s: PNode, a, b: PNode): bool
proc emptyRange*(a, b: PNode): bool
proc SetHasRange*(s: PNode): bool
# returns true if set contains a range (needed by the code generator)
# these are used for constant folding:
proc unionSets*(a, b: PNode): PNode
proc diffSets*(a, b: PNode): PNode
proc intersectSets*(a, b: PNode): PNode
proc symdiffSets*(a, b: PNode): PNode
proc containsSets*(a, b: PNode): bool
proc equalSets*(a, b: PNode): bool
proc cardSet*(s: PNode): BiggestInt
# implementation
proc inSet(s: PNode, elem: PNode): bool =
if s.kind != nkCurly: InternalError(s.info, "inSet")
for i in countup(0, sonsLen(s) - 1):
if s.sons[i].kind == nkRange:
if leValue(s.sons[i].sons[0], elem) and
leValue(elem, s.sons[i].sons[1]):
return true
else:
if sameValue(s.sons[i], elem):
return true
result = false
proc overlap(a, b: PNode): bool =
if a.kind == nkRange:
if b.kind == nkRange:
result = leValue(a.sons[0], b.sons[1]) and
leValue(b.sons[1], a.sons[1]) or
leValue(a.sons[0], b.sons[0]) and leValue(b.sons[0], a.sons[1])
else:
result = leValue(a.sons[0], b) and leValue(b, a.sons[1])
else:
if b.kind == nkRange:
result = leValue(b.sons[0], a) and leValue(a, b.sons[1])
else:
result = sameValue(a, b)
proc SomeInSet(s: PNode, a, b: PNode): bool =
# checks if some element of a..b is in the set s
if s.kind != nkCurly: InternalError(s.info, "SomeInSet")
for i in countup(0, sonsLen(s) - 1):
if s.sons[i].kind == nkRange:
if leValue(s.sons[i].sons[0], b) and leValue(b, s.sons[i].sons[1]) or
leValue(s.sons[i].sons[0], a) and leValue(a, s.sons[i].sons[1]):
return true
else:
# a <= elem <= b
if leValue(a, s.sons[i]) and leValue(s.sons[i], b):
return true
result = false
proc toBitSet(s: PNode, b: var TBitSet) =
var first, j: BiggestInt
first = firstOrd(s.typ.sons[0])
bitSetInit(b, int(getSize(s.typ)))
for i in countup(0, sonsLen(s) - 1):
if s.sons[i].kind == nkRange:
j = getOrdValue(s.sons[i].sons[0])
while j <= getOrdValue(s.sons[i].sons[1]):
BitSetIncl(b, j - first)
inc(j)
else:
BitSetIncl(b, getOrdValue(s.sons[i]) - first)
proc ToTreeSet(s: TBitSet, settype: PType, info: TLineInfo): PNode =
var
a, b, e, first: BiggestInt # a, b are interval borders
elemType: PType
n: PNode
elemType = settype.sons[0]
first = firstOrd(elemType)
result = newNodeI(nkCurly, info)
result.typ = settype
result.info = info
e = 0
while e < high(s) * elemSize:
if bitSetIn(s, e):
a = e
b = e
while true:
Inc(b)
if (b > high(s) * elemSize) or not bitSetIn(s, b): break
Dec(b)
if a == b:
addSon(result, newIntTypeNode(nkIntLit, a + first, elemType))
else:
n = newNodeI(nkRange, info)
n.typ = elemType
addSon(n, newIntTypeNode(nkIntLit, a + first, elemType))
addSon(n, newIntTypeNode(nkIntLit, b + first, elemType))
addSon(result, n)
e = b
Inc(e)
type
TSetOP = enum
soUnion, soDiff, soSymDiff, soIntersect
proc nodeSetOp(a, b: PNode, op: TSetOp): PNode =
var x, y: TBitSet
toBitSet(a, x)
toBitSet(b, y)
case op
of soUnion: BitSetUnion(x, y)
of soDiff: BitSetDiff(x, y)
of soSymDiff: BitSetSymDiff(x, y)
of soIntersect: BitSetIntersect(x, y)
result = toTreeSet(x, a.typ, a.info)
proc unionSets(a, b: PNode): PNode =
result = nodeSetOp(a, b, soUnion)
proc diffSets(a, b: PNode): PNode =
result = nodeSetOp(a, b, soDiff)
proc intersectSets(a, b: PNode): PNode =
result = nodeSetOp(a, b, soIntersect)
proc symdiffSets(a, b: PNode): PNode =
result = nodeSetOp(a, b, soSymDiff)
proc containsSets(a, b: PNode): bool =
var x, y: TBitSet
toBitSet(a, x)
toBitSet(b, y)
result = bitSetContains(x, y)
proc equalSets(a, b: PNode): bool =
var x, y: TBitSet
toBitSet(a, x)
toBitSet(b, y)
result = bitSetEquals(x, y)
proc cardSet(s: PNode): BiggestInt =
# here we can do better than converting it into a compact set
# we just count the elements directly
result = 0
for i in countup(0, sonsLen(s) - 1):
if s.sons[i].kind == nkRange:
result = result + getOrdValue(s.sons[i].sons[1]) -
getOrdValue(s.sons[i].sons[0]) + 1
else:
Inc(result)
proc SetHasRange(s: PNode): bool =
if s.kind != nkCurly: InternalError(s.info, "SetHasRange")
for i in countup(0, sonsLen(s) - 1):
if s.sons[i].kind == nkRange:
return true
result = false
proc emptyRange(a, b: PNode): bool =
result = not leValue(a, b) # a > b iff not (a <= b)
|