Re: stack overflow on Sparc64

From: David Miller
Date: Thu Jun 19 2008 - 00:00:01 EST


From: Mikulas Patocka <mpatocka@xxxxxxxxxx>
Date: Wed, 18 Jun 2008 23:24:20 -0400 (EDT)

> BTW. what's the purpose of having 192-byte stack frame? There are 16
> 8-byte registers being saved per function call, so 128-byte frame should
> be sufficient, shoudn't? The ABI specifies that some additional entries
> must be present even if unused, but I don't see reason for them. Would
> something bad happen if GCC started to generate 128-byte stacks?

The callee can pop the arguments into the area past the
register window.

So you have the 128 byte register window save area, 6
slots for incoming arguments, which gives us 176 bytes.
The rest is for some miscellaneous stack frame state,
which I don't remember the details of at the moment.
I'd have to read the sparc backend of gcc to remember.
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