constructing cfg from linked binary for arm

[Kugan Vivekanandarajah <kuganv at gmail dot com>]

[Might be off topic for this list, but I could not find any list which
discusses the arm gcc backend]

To study the program behavior, after being linked (which will be used
for application specific architecture tuning), I need to construct a
control flow graph for the whole program. My target architecture is
arm. I have following questions

1)	Can function return take place with any other instruction other
than the following? And also, can I assume that this instructions will
be used only for function return
a.	mov	pc, lr
b.	ldmdb   fp, {r4, fp, sp, pc}
2)	Instructions like the following: what is the genral use of them?
a.	ldr	pc, [r4]. #4
b.	mov pc, r8
Can I get these informations by looking arm.md file used in GCC.  How
des gcc generates code based on this md file.

Any points, links or documents about this will be very helpful

Thanks in advance,
-kgn