Subject: Re: Shared library support for ARM ELF
To: Ben Harris <bjh21@netbsd.org>
From: Todd Vierling <tv@wasabisystems.com>
List: port-arm
Date: 07/20/2001 12:12:00
On Fri, 20 Jul 2001, Ben Harris wrote:

: > What else is required?
:
: MASK_RETURN_ADDR needs to be changed to generate code to check what mode
: the CPU is in at run-time and pick the correct mask appropriately.
: sys/arch/arm/include/profile.h demonstrates how to do this, but it needs
: to be converted to a form GCC can understand.

The mask is needed when gcc is *compiling* code, so how would this be done
at run-time?  (Generation of code that does it on every return insn?  Eek,
that sounds like a significant overhead added to function calls....)  Note
I'm reading from your definition of "run-time" here that you are implying
a program's run-time, not gcc's.

If, instead, you're talking about the "run-time" of gcc itself, where gcc is
in the middle of compiling code, it should determine nothing about the host
CPU.  It must have fixed defaults for a given target, and you must use
switches to change codegen behavior.

-- 
-- Todd Vierling <tv@wasabisystems.com>  *  Wasabi NetBSD:  Run with it.
-- NetBSD 1.5 now available on CD-ROM  --  http://www.wasabisystems.com/