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
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
|
discard """
outputsub: '''1
2
3
4
5
6
89
90
90
0 0 1
0 1 2
0 2 3
1 0 4
1 1 5
1 2 6
1 3 7
after 6 6
MEM 0'''
joinable: false
cmd: "nim c --gc:orc -d:useMalloc $file"
valgrind: "true"
"""
import typetraits
type
myseq*[T] = object
len, cap: int
data: ptr UncheckedArray[T]
# XXX make code memory safe for overflows in '*'
var
allocCount, deallocCount: int
proc `=destroy`*[T](x: var myseq[T]) =
if x.data != nil:
when not supportsCopyMem(T):
for i in 0..<x.len: `=destroy`(x[i])
dealloc(x.data)
inc deallocCount
x.data = nil
x.len = 0
x.cap = 0
proc `=copy`*[T](a: var myseq[T]; b: myseq[T]) =
if a.data == b.data: return
if a.data != nil:
`=destroy`(a)
#dealloc(a.data)
#inc deallocCount
#a.data = nil
a.len = b.len
a.cap = b.cap
if b.data != nil:
a.data = cast[type(a.data)](alloc(a.cap * sizeof(T)))
inc allocCount
when supportsCopyMem(T):
copyMem(a.data, b.data, a.cap * sizeof(T))
else:
for i in 0..<a.len:
a.data[i] = b.data[i]
proc `=sink`*[T](a: var myseq[T]; b: myseq[T]) =
if a.data != nil and a.data != b.data:
dealloc(a.data)
inc deallocCount
a.len = b.len
a.cap = b.cap
a.data = b.data
proc `=trace`*[T](x: var myseq[T]; env: pointer) =
if x.data != nil:
for i in 0..<x.len: `=trace`(x[i], env)
proc resize[T](s: var myseq[T]) =
let oldCap = s.cap
if oldCap == 0: s.cap = 8
else: s.cap = (s.cap * 3) shr 1
if s.data == nil: inc allocCount
s.data = cast[typeof(s.data)](realloc0(s.data, oldCap * sizeof(T), s.cap * sizeof(T)))
proc reserveSlot[T](x: var myseq[T]): ptr T =
if x.len >= x.cap: resize(x)
result = addr(x.data[x.len])
inc x.len
template add*[T](x: var myseq[T]; y: T) =
reserveSlot(x)[] = y
proc shrink*[T](x: var myseq[T]; newLen: int) =
assert newLen <= x.len
assert newLen >= 0
when not supportsCopyMem(T):
for i in countdown(x.len - 1, newLen - 1):
`=destroy`(x.data[i])
x.len = newLen
proc grow*[T](x: var myseq[T]; newLen: int; value: T) =
if newLen <= x.len: return
assert newLen >= 0
let oldCap = x.cap
if oldCap == 0: x.cap = newLen
else: x.cap = max(newLen, (oldCap * 3) shr 1)
if x.data == nil: inc allocCount
x.data = cast[type(x.data)](realloc0(x.data, oldCap * sizeof(T), x.cap * sizeof(T)))
for i in x.len..<newLen:
x.data[i] = value
x.len = newLen
template default[T](t: typedesc[T]): T =
var v: T
v
proc setLen*[T](x: var myseq[T]; newLen: int) {.deprecated.} =
if newlen < x.len: shrink(x, newLen)
else: grow(x, newLen, default(T))
template `[]`*[T](x: myseq[T]; i: Natural): T =
assert i < x.len
x.data[i]
template `[]=`*[T](x: myseq[T]; i: Natural; y: T) =
assert i < x.len
x.data[i] = y
proc createSeq*[T](elems: varargs[T]): myseq[T] =
result.cap = max(elems.len, 2)
result.len = elems.len
result.data = cast[type(result.data)](alloc0(result.cap * sizeof(T)))
inc allocCount
when supportsCopyMem(T):
copyMem(result.data, unsafeAddr(elems[0]), result.cap * sizeof(T))
else:
for i in 0..<result.len:
result.data[i] = elems[i]
proc len*[T](x: myseq[T]): int {.inline.} = x.len
proc main =
var s = createSeq(1, 2, 3, 4, 5, 6)
s.add 89
s.grow s.len + 2, 90
for i in 0 ..< s.len:
echo s[i]
var nested = createSeq(createSeq(1, 2, 3), createSeq(4, 5, 6, 7))
for i in 0 ..< nested.len:
for j in 0 ..< nested[i].len:
echo i, " ", j, " ", nested[i][j]
main()
echo "after ", allocCount, " ", deallocCount
type
Node = ref object
name: char
sccId: int
kids: myseq[Node]
rc: int
proc edge(a, b: Node) =
inc b.rc
a.kids.add b
proc createNode(name: char): Node =
new result
result.name = name
result.kids = createSeq[Node]()
proc use(x: Node) = discard
proc buildComplexGraph: Node =
# see https://en.wikipedia.org/wiki/Strongly_connected_component for the
# graph:
let a = createNode('a')
let b = createNode('b')
let c = createNode('c')
let d = createNode('d')
let e = createNode('e')
a.edge c
c.edge b
c.edge e
b.edge a
d.edge c
e.edge d
let f = createNode('f')
b.edge f
e.edge f
let g = createNode('g')
let h = createNode('h')
let i = createNode('i')
f.edge g
f.edge i
g.edge h
h.edge i
i.edge g
let j = createNode('j')
h.edge j
i.edge j
let k = createNode('k')
let l = createNode('l')
f.edge k
k.edge l
l.edge k
k.edge j
let m = createNode('m')
let n = createNode('n')
let p = createNode('p')
let q = createNode('q')
m.edge n
n.edge p
n.edge q
q.edge p
p.edge m
q.edge k
d.edge m
e.edge n
result = a
proc main2 =
let g = buildComplexGraph()
main2()
GC_fullCollect()
echo "MEM ", getOccupiedMem()
|