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Table 22-27. Program Trace Correction Due to a Mispredicted Branch (continued)
Time
6
7
8
9
10
11
12
13
14
15
16
17
18
At Time 11, the Indirect Branch is mispredicted taken.
At Time 15, branch correction occurs due to the mispredicted branch which was taken at Time 11. A
program trace correction message is sent out correcting the number of instructions in the trace (1).
Sequential instruction which occurred at Time 12, 13, and 14 respectively are not included in the
correction count because the tool is not aware that they occurred (they were not transmitted out).
At Time 18, the Indirect Branch Message indicates that 3 sequential instructions were executed since
trace correction (this includes the mispredicted branch instruction which is considered to be a sequential
instruction).
Table 22-28. Program Trace Correction Due to an Exception
Time
1
2
3
MOTOROLA
PRELIMINARY—SUBJECT TO CHANGE WITHOUT NOTICE
Processor State
Direct Branch Instruction
Sequential Instruction
Sequential Instruction
Sequential Instruction
Sequential Instruction
Indirect Branch Instruction
(mispredicted taken)
Sequential Instruction
Sequential Instruction
Sequential Instruction
Branch Correction
Sequential Instruction
Sequential Instruction
Indirect Branch Instruction
(predicted taken)
Processor State
Sequential Instruction
Sequential Instruction
Sequential Instruction
Chapter 22. READI Module
Message sent
Direct Branch Message
TCODE = 3
Number of sequential instructions executed
since last taken branch = 5
Indirect Branch Message
TCODE = 4
Number of sequential instructions executed
since last taken branch = 4
Unique portion of the target address
Program Trace Correction Message
TCODE = 10
Number of instructions to rewind from trace = 1
Indirect Branch Message
TCODE = 4
Number of sequential instructions executed
since last valid taken branch = 3
Unique portion of the target address
Message sent
Program Trace
22-43
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