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To: Daniel Jacobowitz <drow@false.org>
Cc: Jim Blandy <jimb@redhat.com>, gdb-patches@sourceware.org
Subject: Re: RFA: general prologue analysis framework
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	<20051007213028.GA2371@nevyn.them.org>
From: "Nathan J. Williams" <nathanw@wasabisystems.com>
Date: Fri, 07 Oct 2005 21:41:00 -0000
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Daniel Jacobowitz <drow@false.org> writes:

> If you're guaranteed that the compiler only adjusts the stack pointer
> by constant amounts, either in the prologue or down and then up again
> within a basic block, maybe it would be useful.  But very few compilers
> behave that way.
> 
> Did your compiler really give you that guarantee?

Observationally, it only ever adjusted the stack pointer by constant
amounts, though it did it wherever it felt like. I don't think the
compiler was smart enough to do anything more complicated than
constant adjustments.

As far as actual guarantees, I have no idea. It was a binary product
and my customer was barely on speaking terms with their compiler
vendor.

        - Nathan