1 #include "config.h"
2 #include "types.h"
3
4 u32 skim(const u32 *virgin, const u32 *current, const u32 *current_end);
5 u32 classify_word(u32 word);
6
classify_word(u32 word)7 inline u32 classify_word(u32 word) {
8
9 u16 mem16[2];
10 memcpy(mem16, &word, sizeof(mem16));
11
12 mem16[0] = count_class_lookup16[mem16[0]];
13 mem16[1] = count_class_lookup16[mem16[1]];
14
15 memcpy(&word, mem16, sizeof(mem16));
16 return word;
17
18 }
19
simplify_trace(afl_state_t * afl,u8 * bytes)20 void simplify_trace(afl_state_t *afl, u8 *bytes) {
21
22 u32 *mem = (u32 *)bytes;
23 u32 i = (afl->fsrv.map_size >> 2);
24
25 while (i--) {
26
27 /* Optimize for sparse bitmaps. */
28
29 if (unlikely(*mem)) {
30
31 u8 *mem8 = (u8 *)mem;
32
33 mem8[0] = simplify_lookup[mem8[0]];
34 mem8[1] = simplify_lookup[mem8[1]];
35 mem8[2] = simplify_lookup[mem8[2]];
36 mem8[3] = simplify_lookup[mem8[3]];
37
38 } else
39
40 *mem = 0x01010101;
41
42 mem++;
43
44 }
45
46 }
47
classify_counts(afl_forkserver_t * fsrv)48 inline void classify_counts(afl_forkserver_t *fsrv) {
49
50 u32 *mem = (u32 *)fsrv->trace_bits;
51 u32 i = (fsrv->map_size >> 2);
52
53 while (i--) {
54
55 /* Optimize for sparse bitmaps. */
56
57 if (unlikely(*mem)) { *mem = classify_word(*mem); }
58
59 mem++;
60
61 }
62
63 }
64
65 /* Updates the virgin bits, then reflects whether a new count or a new tuple is
66 * seen in ret. */
discover_word(u8 * ret,u32 * current,u32 * virgin)67 inline void discover_word(u8 *ret, u32 *current, u32 *virgin) {
68
69 /* Optimize for (*current & *virgin) == 0 - i.e., no bits in current bitmap
70 that have not been already cleared from the virgin map - since this will
71 almost always be the case. */
72
73 if (unlikely(*current & *virgin)) {
74
75 if (likely(*ret < 2)) {
76
77 u8 *cur = (u8 *)current;
78 u8 *vir = (u8 *)virgin;
79
80 /* Looks like we have not found any new bytes yet; see if any non-zero
81 bytes in current[] are pristine in virgin[]. */
82
83 if (unlikely((cur[0] && vir[0] == 0xff) || (cur[1] && vir[1] == 0xff) ||
84 (cur[2] && vir[2] == 0xff) || (cur[3] && vir[3] == 0xff)))
85 *ret = 2;
86 else
87 *ret = 1;
88
89 }
90
91 *virgin &= ~*current;
92
93 }
94
95 }
96
97 #define PACK_SIZE 16
skim(const u32 * virgin,const u32 * current,const u32 * current_end)98 inline u32 skim(const u32 *virgin, const u32 *current, const u32 *current_end) {
99
100 for (; current < current_end; virgin += 4, current += 4) {
101
102 if (unlikely(current[0] && classify_word(current[0]) & virgin[0])) return 1;
103 if (unlikely(current[1] && classify_word(current[1]) & virgin[1])) return 1;
104 if (unlikely(current[2] && classify_word(current[2]) & virgin[2])) return 1;
105 if (unlikely(current[3] && classify_word(current[3]) & virgin[3])) return 1;
106
107 }
108
109 return 0;
110
111 }
112
113