1		i	synthesize instructions events
 2		b	synthesize branches events
 3		c	synthesize branches events (calls only)
 4		r	synthesize branches events (returns only)
 5		x	synthesize transactions events
 6		e	synthesize error events
 7		d	create a debug log
 8		g	synthesize a call chain (use with i or x)
 9		l	synthesize last branch entries (use with i or x)
10
11	The default is all events i.e. the same as --itrace=ibxe
12
13	In addition, the period (default 100000) for instructions events
14	can be specified in units of:
15
16		i	instructions
17		t	ticks
18		ms	milliseconds
19		us	microseconds
20		ns	nanoseconds (default)
21
22	Also the call chain size (default 16, max. 1024) for instructions or
23	transactions events can be specified.
24
25	Also the number of last branch entries (default 64, max. 1024) for
26	instructions or transactions events can be specified.