<html><head><meta http-equiv="Content-Type" content="text/html charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><br class=""><div><blockquote type="cite" class=""><div class="">On Jan 7, 2015, at 2:25 PM, Owen Anderson <<a href="mailto:resistor@mac.com" class="">resistor@mac.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><meta http-equiv="content-type" content="text/html; charset=utf-8" class=""><div dir="auto" class=""><div class="">I'm not aware of any such restriction, and I know of several LLVM based systems that use address space 1 for something other than that.<br class=""><br class="">-Owen</div></div></div></blockquote><div><br class=""></div><div>Yes, this would be a problem for us. We use 1 for a normal address space where 0 is invalid. However, we also have a problem where some other address spaces do want 0 to be a valid address, which just sort of don’t work correctly now.</div><div><br class=""></div><div>-Matt</div><div><br class=""></div><div><br class=""></div><br class=""><blockquote type="cite" class=""><div class=""><div dir="auto" class=""><div class=""><br class="">On Jan 7, 2015, at 1:18 PM, Philip Reames <<a href="mailto:listmail@philipreames.com" class="">listmail@philipreames.com</a>> wrote:<br class=""><br class=""></div><blockquote type="cite" class=""><div class="">
<meta http-equiv="content-type" content="text/html; charset=utf-8" class="">
On the review for <a class="moz-txt-link-freetext" href="http://reviews.llvm.org/D6808">http://reviews.llvm.org/D6808</a>, <a href="http://reviews.llvm.org/p/majnemer/" class=" phui-handle
phui-link-person">majnemer</a> commented that:<br class="">
<span class="transaction-comment" data-sigil="transaction-comment" data-meta="14_7">"Address space 1 has a special meaning in LLVM,
it's identical to address space 0 except for the fact that "null"
may be dereferenced. You might want to consider a different
address space."<br class="">
<br class="">
This is the first I've heard of this and I can't find any
documentation about it being reserved, either in general, or
specifically for x86. Can anyone clarify?<br class="">
<br class="">
The only address spaces with special meanings I know of are:<br class="">
- 0 (the normal address space, null is not dereferencable)<br class="">
- 256 - TLS, GS relative addressing<br class="">
- 257 - FS relative addressing<br class="">
<br class="">
Philip<br class="">
</span>
</div></blockquote><blockquote type="cite" class=""><div class=""><span class="">_______________________________________________</span><br class=""><span class="">LLVM Developers mailing list</span><br class=""><span class=""><a href="mailto:LLVMdev@cs.uiuc.edu" class="">LLVMdev@cs.uiuc.edu</a> <a href="http://llvm.cs.uiuc.edu/" class="">http://llvm.cs.uiuc.edu</a></span><br class=""><span class=""><a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev" class="">http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev</a></span><br class=""></div></blockquote></div>_______________________________________________<br class="">LLVM Developers mailing list<br class=""><a href="mailto:LLVMdev@cs.uiuc.edu" class="">LLVMdev@cs.uiuc.edu</a> <a href="http://llvm.cs.uiuc.edu" class="">http://llvm.cs.uiuc.edu</a><br class=""><a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev" class="">http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev</a><br class=""></div></blockquote></div><br class=""></body></html>