BR trace entries

A BR trace entry represents processing of a Branch and Link (BALR), Branch and Save (BASR), Branch and Save and Set Mode (BASSM), or Branch and Stack (BAKR) instruction, when the R₂ field in the instruction is not zero. These branches are traced only when a TRACE operator command requests branch tracing by BR=ON.

 PR ASID TCB-ADDR  IDENT CD/D PSW----- ADDRESS- UNIQUE-1 UNIQUE-2 UNIQUE-3  PSACLHS- PSALOCAL PASD SASD TIMESTAMP-RECORD  CP
                                                UNIQUE-4 UNIQUE-5 UNIQUE-6

 pr last tcb-addr  BR        address- address-  address- address- address- address- etc. 

PR

pr: Identifier of the processor that produced the TTE.

ASID

last: Last home address space identifier (ASID) in the trace buffer.

TCB-ADDR

tcb-addr: Address of the task control block (TCB) for the current task for which the TTE was produced.

IDENT

The TTE identifier, as follows:

BR

Branch instruction

CD/D

Blank

PSW----- ADDRESS-

UNIQUE-1/UNIQUE-2/UNIQUE-3

UNIQUE-4/UNIQUE-5/UNIQUE-6

PSACLHS-

PSALOCAL

PASD

SASD

TIMESTAMP-RECORD

CP

address-: Successful branch address, repeated for consecutive branches on the BR entry. Addresses appear in the following formats:

Addressing mode and location	Appearance
24-bit address	xxxxxx
31-bit address	xxxxxxxx
64-bit address with zeros in high order bits	00_xxxxxxxx
64-bit address with non-zero high order bits	xxxxxxxx_xxxxxxxx