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
|
#pragma once
#include <stdbool.h>
#define UNUSED __attribute__((unused))
struct bitslice_run {
int inpos, outpos, len;
};
struct bitslice {
int nruns;
const struct bitslice_run *runs;
};
struct dis_data_operand {
struct bitslice n;
bool out;
};
static inline int sext(unsigned val, int bits) {
return val & (1 << (bits - 1)) ? ((int)val - (1 << bits)) : (int)val;
}
static inline unsigned bs_get(struct bitslice bs, unsigned op) {
unsigned ret = 0;
for(int i = 0; i < bs.nruns; i++) {
const struct bitslice_run *run = &bs.runs[i];
unsigned val = (op >> run->inpos) & ((1 << run->len) - 1);
ret |= val << run->outpos;
}
return ret;
}
static inline unsigned bs_set(struct bitslice bs, unsigned new, unsigned op) {
for(int i = 0; i < bs.nruns; i++) {
const struct bitslice_run *run = &bs.runs[i];
unsigned mask = (1 << run->len) - 1;
unsigned val = (new >> run->outpos) & mask;
op = (op & ~(mask << run->inpos)) | (val << run->inpos);
}
return op;
}
static inline struct bitslice bs_slice_(struct bitslice bs, struct bitslice_run *runs, int lo, int size) {
int nruns = 0;
for(int i = 0; i < bs.nruns; i++) {
struct bitslice_run inr = bs.runs[i];
inr.outpos -= lo;
if(inr.outpos < 0) {
inr.len += inr.outpos;
inr.inpos -= inr.outpos;
inr.outpos = 0;
}
if(inr.outpos + inr.len > size)
inr.len = size - inr.outpos;
if(inr.len > 0)
runs[nruns++] = (struct bitslice_run) {inr.inpos, inr.outpos, inr.len};
}
return (struct bitslice) {nruns, runs};
}
#define bs_slice(bs, lo, size) \
bs_slice_(bs, alloca((bs).nruns * sizeof(struct bitslice_run)), lo, size)
|
