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

Address	Instruction	Trace, if any, with explanation
`0x1000`	`MOV`	-
`0x1004`	`ADD`	-
`0x1008`	`B 0x1100`	Direct branch taken. E atom generated.
`0x1100`	`MOV`	-
`0x1104`	LDR	-
`0x1108`	`ADD`	-
`0x110C`	CMP	-
`0x1110`	`BNE 0x1104`	Direct branch taken. E atom generated.
`0x1104`	LDR	-
`0x1108`	`ADD`	-
`0x110C`	CMP	-
`0x1110`	`BNE 0x1104`	Direct branch taken. E atom generated.
`0x1104`	LDR	-
`0x1108`	`ADD`	-
`0x110C`	CMP	-
`0x1110`	`BNE 0x1104`	Direct branch not taken. N atom generated.
`0x1114`	`LDR`	-
`0x1118`	`STR`	-
`0x111C`	`MOV PC, Rn`	Indirect branch taken. Generate branch address packet indicating new address, `0x2000`.
`0x2000`	`MOV`	-
`0x2004`	`ADD`	-
`0x2008`	`MOVEQ PC, Rm`	Indirect branch not taken. N atom generated.
`0x200C`	`MOV`	-
`0x2010`	`ADD`	-
`0x2014`	`LDR PC`	Indirect branch taken. Generate branch address packet indicating new address, `0x3000`.
`0x3000`	`MOV`	-
`0x3004`	`ADD`	-
`0x3008`	`SUB`	-
`0x300C`	`MOV`	-
`0x3010`	`ADD`	-
`0x3014`	`SUB`	-
`0x3018`	`MOV`	-
`0x301C`	`ADD`	-
`0x3020`	`SUB`	-
`0x3024`	`MOV`	-
`0x3028`	`ADD`	-
`0x302C`	`SUB`	-
`0x3030`	`MOV`	-
`0x3034`	`ADD`	-
-	IRQ taken	Exception taken. Generate packets indicating address of last instruction executed, `0x3034`, and destination address, `0x0018`.
`0x0018`	`ADD`	No trace. This is the start of the IRQ exception handler.
Processor continues execution of the IRQ handler.

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