7.14.1. ETMv2 PIPESTAT encodings and ETMv3 P-headers compared

ETMv3.0 provides alternative mechanisms for indicating the trigger and trace disabled conditions. These mechanisms replace the TR and WT pipeline status codes. When data appears in the trace stream, it always corresponds to the most recent cycle or instruction. This means it is not necessary to indicate whether data follows, and therefore the remaining 14 pipeline status conditions reduce to seven possibilities. These can be represented as a combination of the following three P-header atoms:

Table 7.22 shows the mappings.

Table 7.22. Mappings from pipeline status to P-header atoms

Pipeline status

Atoms
Instruction executed (IE), instruction executed with data (DE)W,E
Instruction not executed (IN), instruction not executed with data (DN)W,N
Wait (WT), wait with data (DW)W
Trigger (TR), trace disabled (TD)Not applicable
Branch phantom taken plus instruction executed (PTIE), branch phantom taken plus instruction executed with data (PTDE)W,E,E
Branch phantom taken plus instruction not executed (PTIN), branch phantom taken plus instruction not executed with data (PTDN)W,E,N
Branch phantom not taken plus instruction executed (PNIE), branch phantom not taken plus instruction executed with data (PNDE)W,N,E
Branch phantom not taken plus instruction not executed (PNIN), branch phantom not taken plus instruction not executed with data (PNDN)W,N,N

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