2.1.4. PFT trace example

Table 2.1 shows an instruction flow, executing ARM instructions, that includes examples of branch execution, and an exception, and the PFT trace generated, for a PTM that is not using a return stack.

Table 2.1. PTM trace example

AddressInstructionTrace, if any, with explanation
0x1000MOV-
0x1004ADD-
0x1008B 0x1100Direct branch taken. E atom generated.
0x1100MOV-
0x1104LDR-
0x1108ADD-
0x110CCMP-
0x1110BNE 0x1104Direct branch taken. E atom generated.
0x1104LDR-
0x1108ADD-
0x110CCMP-
0x1110BNE 0x1104Direct branch taken. E atom generated.
0x1104LDR-
0x1108ADD-
0x110CCMP-
0x1110BNE 0x1104Direct branch not taken. N atom generated.
0x1114LDR-
0x1118STR-
0x111CMOV PC, RnIndirect branch taken. Generate branch address packet indicating new address, 0x2000.
0x2000MOV-
0x2004ADD-
0x2008MOVEQ PC, RmIndirect branch not taken. N atom generated.
0x200CMOV-
0x2010ADD-
0x2014LDR PCIndirect branch taken. Generate branch address packet indicating new address, 0x3000.
0x3000MOV-
0x3004ADD-
0x3008SUB-
0x300CMOV-
0x3010ADD-
0x3014SUB-
0x3018MOV-
0x301CADD-
0x3020SUB-
0x3024MOV-
0x3028ADD-
0x302CSUB-
0x3030MOV-
0x3034ADD-
-IRQ takenException taken. Generate packets indicating address of last instruction executed, 0x3034, and destination address, 0x0018.
0x0018ADDNo trace. This is the start of the IRQ exception handler.
Processor continues execution of the IRQ handler.

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