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Re: [PATCH, MPX, 2/X] Pointers Checker [14/25] Function splitting


On 11/18/13 12:12, Ilya Enkovich wrote:
2013/11/18 Jeff Law <law@redhat.com>:
On 11/18/13 11:27, Ilya Enkovich wrote:


How does pointer passed to regular function differ from pointer passed
to splitted function? How do I know then which pointer is to be passed
with bounds and wchich one is not? Moreover current ABI does not allow
to pass bounds with no pointer or pass bounds for some pointers in the
call only.

But I don't see any case in function splitting where we're going to want to
pass the pointer without the bounds.  If you want the former, you're going
to want the latter.

There are at least cases when checks are eliminated or when lots of
pointer usages are accompanied with few checks performed earlier (e.g.
we are working with array). In such cases splitted part may easily get
no bounds.
So your assertion is we can have a split point that sits between the checks and uses of a bounded pointer? I can buy that, so to speak.

I'll also note that the all-or-nothing nature of the ABI is part of the problem here.

Jeff


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