[prev in list] [next in list] [prev in thread] [next in thread] 

List:       9fans
Subject:    Re: [9fans] getcallerpc on arm7
From:       Michael Teichgräber <mt () wmipf ! in-berlin ! de>
Date:       2008-03-31 22:34:06
Message-ID: 47F166DE.6090502 () wmipf ! in-berlin ! de
[Download RAW message or body]

> it should be the same as the other risc machines, and seems all right
> when i test it with 5c/5l.  gcc typically also uses a frame pointer,
> which might make it nearly as easy for that compiler.

This seems to work well:

	.text
	.globl getcallerpc
	getcallerpc:
		ldr	r0, [fp, #-4]
		bx	lr

I was a bit confused about whether or not the firstarg pointer
is expected to be used by a getcallerpc implementation (so that
it would also work in subfunctions of the current, provided
&firstarg is passed down). The BUGS section of getcallerpc(2/3)
gives a hint how this could be answered.

[prev in list] [next in list] [prev in thread] [next in thread]