# StgRun question.

Simon Marlow marlowsd at gmail.com
Thu May 19 10:47:32 CEST 2011

On 13/05/2011 23:32, Karel Gardas wrote:

>
> I'm attempting to make ARM registerised build reality just for own fun
> (and thanks to help and encouragement provided by David Terei) and for
> this I'm writing platform specific StgRun/StgReturn functions as
> required in rts/StgCRun.c. I'm not sure I've got right all the
> information about what's required by those two functions. I've found the
> comments on top of the file not so clear so I tried to make them a
> little bit more clear even for complete novice as me. The question is:
> have I got all this right or have I made foot fault with this?

Yes, they look fine (modulo a couple of grammatical wibbles that we
could fix later)

> correct me if I'm wrong. The diff is attached. Also I wonder if the last
> note:
>
> * GCC will have assumed that pushing/popping of C-stack frames is
> * going on when it generated its code, and used stack space
> * accordingly. However, we actually {\em post-process away} all
> * such stack-framery (see \tr{ghc/driver/ghc-asm.lprl}). Things will
> * be OK however, if we initially make sure there are
> * @RESERVED_C_STACK_BYTES@ on the C-stack to begin with, for local
> * variables.
>
> is still valid since it looks like coming from the days of -fvia-C
> registerised builds, at least evil mangler note suggest it to me...

Yes, that's irrelevant now.

Cheers,
Simon