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
|
/*
* %CopyrightBegin%
*
* Copyright Ericsson AB 2003-2011. All Rights Reserved.
*
* The contents of this file are subject to the Erlang Public License,
* Version 1.1, (the "License"); you may not use this file except in
* compliance with the License. You should have received a copy of the
* Erlang Public License along with this software. If not, it can be
* retrieved online at http://www.erlang.org/.
*
* Software distributed under the License is distributed on an "AS IS"
* basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
* the License for the specific language governing rights and limitations
* under the License.
*
* %CopyrightEnd%
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "global.h"
#include "hipe_stack.h"
/*
* Native-code stack descriptor hash table.
*
* This uses a specialised version of BEAM's hash table code:
* - Hash table size is always a power of two.
* Permits replacing an expensive integer division operation
* with a cheap bitwise 'and' in the hash index calculation
* - Lookups assume the key is in the table.
* Permits removing NULL checks.
* - Switched order of the hash bucket next and hvalue fields.
* The hvalue field, which must always be checked, gets a zero
* structure offset, which is faster on some architectures;
* the next field is only referenced if hvalue didn't match.
* These changes yield a much more efficient lookup operation.
*/
struct hipe_sdesc_table hipe_sdesc_table;
static struct sdesc **alloc_bucket(unsigned int size)
{
unsigned long nbytes = size * sizeof(struct sdesc*);
struct sdesc **bucket = erts_alloc(ERTS_ALC_T_HIPE, nbytes);
sys_memzero(bucket, nbytes);
return bucket;
}
static void hipe_grow_sdesc_table(void)
{
unsigned int old_size, new_size, new_mask;
struct sdesc **old_bucket, **new_bucket;
unsigned int i;
old_size = 1 << hipe_sdesc_table.log2size;
hipe_sdesc_table.log2size += 1;
new_size = 1 << hipe_sdesc_table.log2size;
new_mask = new_size - 1;
hipe_sdesc_table.mask = new_mask;
old_bucket = hipe_sdesc_table.bucket;
new_bucket = alloc_bucket(new_size);
hipe_sdesc_table.bucket = new_bucket;
for (i = 0; i < old_size; ++i) {
struct sdesc *b = old_bucket[i];
while (b != NULL) {
struct sdesc *next = b->bucket.next;
unsigned int j = (b->bucket.hvalue >> HIPE_RA_LSR_COUNT) & new_mask;
b->bucket.next = new_bucket[j];
new_bucket[j] = b;
b = next;
}
}
erts_free(ERTS_ALC_T_HIPE, old_bucket);
}
struct sdesc *hipe_put_sdesc(struct sdesc *sdesc)
{
unsigned long ra;
unsigned int i;
struct sdesc *chain;
unsigned int size;
ra = sdesc->bucket.hvalue;
i = (ra >> HIPE_RA_LSR_COUNT) & hipe_sdesc_table.mask;
chain = hipe_sdesc_table.bucket[i];
for (; chain != NULL; chain = chain->bucket.next)
if (chain->bucket.hvalue == ra)
return chain; /* collision! (shouldn't happen) */
sdesc->bucket.next = hipe_sdesc_table.bucket[i];
hipe_sdesc_table.bucket[i] = sdesc;
hipe_sdesc_table.used += 1;
size = 1 << hipe_sdesc_table.log2size;
if (hipe_sdesc_table.used > (4*size)/5) /* rehash at 80% */
hipe_grow_sdesc_table();
return sdesc;
}
void hipe_init_sdesc_table(struct sdesc *sdesc)
{
unsigned int log2size, size;
log2size = 10;
size = 1 << log2size;
hipe_sdesc_table.log2size = log2size;
hipe_sdesc_table.mask = size - 1;
hipe_sdesc_table.used = 0;
hipe_sdesc_table.bucket = alloc_bucket(size);
hipe_put_sdesc(sdesc);
}
/*
* XXX: x86 and SPARC currently use the same stack descriptor
* representation. If different representations are needed in
* the future, this code has to be made target dependent.
*/
struct sdesc *hipe_decode_sdesc(Eterm arg)
{
Uint ra, exnra;
Eterm *live;
Uint fsize, arity, nlive, i, nslots, off;
Uint livebitswords, sdescbytes;
void *p;
struct sdesc *sdesc;
if (is_not_tuple(arg) ||
(tuple_val(arg))[0] != make_arityval(6) ||
term_to_Uint((tuple_val(arg))[1], &ra) == 0 ||
term_to_Uint((tuple_val(arg))[2], &exnra) == 0 ||
is_not_small((tuple_val(arg))[3]) ||
(fsize = unsigned_val((tuple_val(arg))[3])) > 65535 ||
is_not_small((tuple_val(arg))[4]) ||
(arity = unsigned_val((tuple_val(arg))[4])) > 255 ||
is_not_tuple((tuple_val(arg))[5]))
return 0;
/* Get tuple with live slots */
live = tuple_val((tuple_val(arg))[5]) + 1;
/* Get number of live slots */
nlive = arityval(live[-1]);
/* Calculate size of frame = locals + ra + arguments */
nslots = fsize + 1 + arity;
/* Check that only valid slots are given. */
for (i = 0; i < nlive; ++i) {
if (is_not_small(live[i]) ||
(off = unsigned_val(live[i]), off >= nslots) ||
off == fsize)
return 0;
}
/* Calculate number of words for the live bitmap. */
livebitswords = (fsize + arity + 1 + 31) / 32;
/* Calculate number of bytes needed for the stack descriptor. */
sdescbytes =
(exnra
? offsetof(struct sdesc_with_exnra, sdesc.livebits)
: offsetof(struct sdesc, livebits))
+ livebitswords * sizeof(int);
p = erts_alloc(ERTS_ALC_T_HIPE, sdescbytes);
/* If we have an exception handler use the
special sdesc_with_exnra structure. */
if (exnra) {
struct sdesc_with_exnra *sdesc_we = p;
sdesc_we->exnra = exnra;
sdesc = &(sdesc_we->sdesc);
} else
sdesc = p;
/* Initialise head of sdesc. */
sdesc->bucket.next = 0;
sdesc->bucket.hvalue = ra;
sdesc->summary = (fsize << 9) | (exnra ? (1<<8) : 0) | arity;
/* Clear all live-bits */
for (i = 0; i < livebitswords; ++i)
sdesc->livebits[i] = 0;
/* Set live-bits given by caller. */
for (i = 0; i < nlive; ++i) {
off = unsigned_val(live[i]);
sdesc->livebits[off / 32] |= (1 << (off & 31));
}
#ifdef DEBUG
{
Eterm mfa_tpl = tuple_val(arg)[6];
sdesc->dbg_M = tuple_val(mfa_tpl)[1];
sdesc->dbg_F = tuple_val(mfa_tpl)[2];
sdesc->dbg_A = tuple_val(mfa_tpl)[3];
}
#endif
return sdesc;
}
|
