<HTML><BODY style="word-wrap: break-word; -khtml-nbsp-mode: space; -khtml-line-break: after-white-space; "><DIV><SPAN class="Apple-style-span" style="border-collapse: separate; border-spacing: 0px 0px; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; text-align: auto; -khtml-text-decorations-in-effect: none; text-indent: 0px; -apple-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><BR class="Apple-interchange-newline"></SPAN> </DIV><BR><DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV>On Mar 25, 2007, at 2:18 AM, Chris Lattner wrote:</DIV><BR class="Apple-interchange-newline"><BLOCKQUOTE type="cite"><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">On Sat, 24 Mar 2007, Christopher Lamb wrote:</DIV> <BLOCKQUOTE type="cite"><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Has there been any discussion of supporting the 'restrict' C99 keyword<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">and C++ extension to boost alias analysis? My impression is that this<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">would require modification of the LLVM IR. I couldn't find any<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">discussion hits using the usual suspects for searches...</DIV> </BLOCKQUOTE><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">So far, there hasn't been a discussion.<SPAN class="Apple-converted-space"> </SPAN>IMO, the most important form is<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">for formal arguments.<SPAN class="Apple-converted-space"> </SPAN>That could easily be added thorough the use of an<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">attribute on the parameter.</DIV></BLOCKQUOTE></DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV>I assume the idea here is to avoid actually attributing the type (as was avoided with signed/unsigned integers by differentiating ops). </DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV>What about an approach not unlike how debugging information is handled? That is have an llvm intrinsic that encodes the known alias free range for a pointer.</DIV><BR><DIV><DIV>--</DIV><DIV>Christopher Lamb</DIV><DIV><A href="mailto:christopher.lamb@gmail.com">christopher.lamb@gmail.com</A></DIV></DIV><BR></BODY></HTML>