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<div class="moz-cite-prefix">On 12/14/2017 11:14 PM, Matt Arsenault
wrote:<br>
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cite="mid:0A27A1D6-62E6-4E6B-98BB-9036658118B5@gmail.com"
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<div class="">On Dec 14, 2017, at 20:28, Hal Finkel via
llvm-dev <<a moz-do-not-send="true"
href="mailto:llvm-dev@lists.llvm.org" class="">llvm-dev@lists.llvm.org</a>>
wrote:</div>
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class="">Would that address your use case? Or can you have
null dereferenceable pointers in that address space, just
not ones from alloca?</span><br style="font-family:
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I would like to clarify what “null” means exactly. One related
thing I would like in the future is for the DataLayout to specify
what numeric value is the invalid, non-dereferencalbe pointer.
i.e. the invalid pointer does is a some non-0 bit pattern like -1.</blockquote>
<br>
Okay. That's certainly a separate discussion. For the purpose of
this question I mean null as zero. Can you have dereferenceable
pointers, with a value of zero when converted to an integer, in that
address space? Or are you interested only in saying that alloca
never produces pointers with a value of zero when converted to an
integer?<br>
<br>
Thanks again,<br>
Hal<br>
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<div class="">-Matt</div>
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<pre class="moz-signature" cols="72">--
Hal Finkel
Lead, Compiler Technology and Programming Languages
Leadership Computing Facility
Argonne National Laboratory</pre>
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