doc/getting_started.md

Getting Started {#start}
========================

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This chapter gives a brief introduction into the sample tools using one of
the tests as example.  It assumes that you are already familiar with
Intel(R) Processor Trace (Intel PT) and that you already built the decoder
library and the sample tools.

For detailed information about Intel PT, please refer to the respective
chapter in Volume 3 of the Intel Software Developer's Manual at
https://www.intel.com/sdm.

Start by compiling the loop-tnt test.  It consists of a small assembly program
with interleaved Intel PT directives:

	$ pttc test/src/loop-tnt.ptt
	loop-tnt-ptxed.exp
	loop-tnt-ptdump.exp

This produces the following output files:

	loop-tnt.lst          a yasm assembly listing file
	loop-tnt.bin          a raw binary file
	loop-tnt.pt           a Intel PT file
	loop-tnt-ptxed.exp    the expected ptxed output
	loop-tnt-ptdump.exp   the expected ptdump output

The latter two files are generated based on the `@pt .exp(<tool>)` directives
found in the `.ptt` file.  They are used for automated testing.  See
script/test.bash for details on that.


Use `ptdump` to dump the Intel PT packets:

	$ ptdump loop-tnt.pt
	0000000000000000  psb
	0000000000000010  fup        3: 0x0000000000100000, ip=0x0000000000100000
	0000000000000017  mode.exec  cs.d=0, cs.l=1 (64-bit mode)
	0000000000000019  psbend
	000000000000001b  tnt8       !!.
	000000000000001c  tip.pgd    3: 0x0000000000100013, ip=0x0000000000100013

The ptdump tool takes an Intel PT file as input and dumps the packets in
human-readable form.  The number on the very left is the offset into the Intel
PT packet stream in hex.  This is followed by the packet opcode and payload.


Use `ptxed` for reconstructing the execution flow.  For this, you need the Intel
PT file as well as the corresponding binary image.  You need to specify the load
address given by the org directive in the .ptt file when using a raw binary
file.

	$ ptxed --pt loop-tnt.pt --raw loop-tnt.bin:0x100000
	0x0000000000100000  mov rax, 0x0
	0x0000000000100007  jmp 0x10000d
	0x000000000010000d  cmp rax, 0x1
	0x0000000000100011  jle 0x100009
	0x0000000000100009  add rax, 0x1
	0x000000000010000d  cmp rax, 0x1
	0x0000000000100011  jle 0x100009
	0x0000000000100009  add rax, 0x1
	0x000000000010000d  cmp rax, 0x1
	0x0000000000100011  jle 0x100009
	[disabled]

Ptxed prints disassembled instructions in execution order as well as status
messages enclosed in brackets.