Vol. 3C 36-37
INTEL® PROCESSOR TRACE
B1…BN represent the last N conditional branch or compressed RET (Section 36.4.2.2) results, such that B1 is oldest
and BN is youngest. The short TNT packet can contain from 1 to 6 TNT bits. The long TNT packet can contain up
from 1 to 47 TNT bits.
Irrespective of how many TNT bits is in a packet, the last valid TNT bit is followed by a trailing 1, or Stop bit, as
shown above. If the TNT packet is not full (fewer than 6 TNT bits for the Short TNT, or fewer than 47 TNT bits for
the Long TNT), the Stop bit moves up, and the trailing bits of the packet are filled with 0s. Examples of these
“partial TNTs” are shown below.
Dependencies
PacketEn
Generation
Scenario
On a conditional branch or compressed RET, if it fills the TNT.
Also, partial TNTs may be generated at any time, as a result of
other packets being generated,
or certain micro-architectural conditions occurring, before the
TNT is full.
Description
Provides the taken/not-taken results for the last 1–N conditional branches (Jcc, J*CXZ, or LOOP) or compressed RETs
(Section 36.4.2.2). The TNT payload bits should be interpreted as follows:
• 1 indicates a taken conditional branch, or a compressed RET
• 0 indicates a not-taken conditional branch
Application
Each valid payload bit (that is, bits between the header bits and the trailing Stop bit) applies to an upcoming condi-
tional branch or RET instruction. Once a decoder consumes a TNT packet with N valid payload bits, these bits should
be applied to (and hence provide the destination for) the next N conditional branches or RETs
Table 36-16. TNT Packet Definition (Contd.)
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
1
0
Long TNT
1
1
0
1
0
0
0
1
1
2
B
40
B
41
B
42
B
43
B
44
B
45
B
46
B
47
3
B
32
B
33
B
34
B
35
B
36
B
37
B
38
B
39
4
B
24
B
25
B
26
B
27
B
28
B
29
B
30
B
31
5
B
16
B
17
B
18
B
19
B
20
B
21
B
22
B
23
6
B
8
B
9
B
10
B
11
B
12
B
13
B
14
B
15
7
1
B
1
B
2
B
3
B
4
B
5
B
6
B
7
7
6
5
4
3
2
1
0
0
0
0
1
B
1
B
2
B
3
B
4
0
Short TNT
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
1
0
Long TNT
1
1
0
1
0
0
0
1
1
2
B
24
B
25
B
26
B
27
B
28
B
29
B
30
B
31
3
B
16
B
17
B
18
B
19
B
20
B
21
B
22
B
23
4
B
8
B
9
B
10
B
11
B
12
B
13
B
14
B
15
5
1
B
1
B
2
B
3
B
4
B
5
B
6
B
7
6
0
0
0
0
0
0
0
0
7
0
0
0
0
0
0
0
0