From mboxrd@z Thu Jan  1 00:00:00 1970
To: 9fans@cse.psu.edu
Subject: Re: [9fans] Fresh (relatively speaking) Graphviz
From: "Russ Cox" <rsc@swtch.com>
Date: Wed,  5 Mar 2008 13:00:54 -0500
In-Reply-To: <c883280d7be68e6142493cb020f4773d@proxima.alt.za>
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cpu% cat getcallerpc.s
TEXT getcallerpc(SB), $0
	MOVL	v+0(FP), AX
	MOVL	-4(AX), AX
	RET

> .globl	getcallerpc
> getcallerpc:
> 	movl	0(%esp),%edx
> 	movl	-4(%edx),%eax
> 	ret

not quite.  0(%esp) is going to be the saved %eip.

getcallerpc:
	movl 4(%esp), %eax
	movl -4(%eax), %eax

or

uint
getcallerpc(void *a)
{
	return ((uint*)a)[-1];
}

russ