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<div>Alireza, </div><div><br class="webkit-block-placeholder"></div><div>I have added full support for embedded C address spaces to the LLVM IR (see <a href="http://llvm.org/docs/LangRef.html#t_pointer">http://llvm.org/docs/LangRef.html#t_pointer</a>). I have not added any support for the fractional types and their operators, though I think this would simply require adding the necessary intrinsics, which is one of the easier things to add to LLVM. Given that LLVM takes the approach of modeling these kinds of type differences as differing operations rather than different types in it's type system it should be fairly straight forward to add them if needed.</div><div><br class="webkit-block-placeholder"></div><div>As far as front-end support goes, I do have changes to my local clang tree which add attributes for address spaces which have been working for my purposes. However since my initial work my free time has become more scarce and I haven't had the opportunity to clean up the patches and submit them back to the tree. </div><div><br class="webkit-block-placeholder"></div><div>The lack of a public back end with which to consume the generated IR with embedded C extensions and validate the front end is also a problem. Without such a platform it will be difficult for the LLVM project to guarantee that the functionality stays working going forward.</div><div><br class="webkit-block-placeholder"></div><div>Do you mind sharing more details about your project, particularly how soon you need the front end support and if you would be able to provide a way (ideally contributed back to LLVM) to regress these features going forward?</div><div><br></div><div><div>--</div><div>Christopher Lamb</div></div><div><br class="webkit-block-placeholder"></div><div><div>On Jan 30, 2008, at 9:53 AM, <<a href="mailto:Alireza.Moshtaghi@microchip.com">Alireza.Moshtaghi@microchip.com</a>> <<a href="mailto:Alireza.Moshtaghi@microchip.com">Alireza.Moshtaghi@microchip.com</a>> wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Thank you Chris,</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">That is great news...</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">So his modifications are in llvm-2.2?</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">How has Christopher tested them? Are there attributes or intrinsics that</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">I can also use?</div><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; ">A.<span class="Apple-converted-space"> </span></div><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; ">-----Original Message-----</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">From: llvmdev-bounces@cs.uiuc.edu [<a href="mailto:llvmdev-bounces@cs.uiuc.edu">mailto:llvmdev-bounces@cs.uiuc.edu</a>]</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">On Behalf Of Chris Lattner</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Sent: Tuesday, January 29, 2008 9:23 PM</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">To: LLVM Developers Mailing List</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Subject: Re: [LLVMdev] C embedded extensions and LLVM</div><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; ">On Jan 29, 2008, at 9:56 AM, <<a href="mailto:Alireza.Moshtaghi@microchip.com">Alireza.Moshtaghi@microchip.com</a>></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><<a href="mailto:Alireza.Moshtaghi@microchip.com">Alireza.Moshtaghi@microchip.com</a><span class="Apple-converted-space"> </span></div> <blockquote type="cite"><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">wrote:</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Christopher,</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">It has been a while since we last talked about C embedded extensions <span class="Apple-converted-space"> </span></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">in</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">LLVM, I was moving back and froth from project to project and didn't <span class="Apple-converted-space"> </span></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">get</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">a chance to follow up. I was wondering if you have made any changes to</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">LLVM IR and if so what has been added. And how can I contribute?</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; ">My understanding is that Christopher's patches have all landed in <span class="Apple-converted-space"> </span></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">llvm, so the IR is capable of capturing and propagating the address <span class="Apple-converted-space"> </span></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">space information.<span class="Apple-converted-space"> </span>However, we have no front-end that correctly <span class="Apple-converted-space"> </span></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">generates this.<span class="Apple-converted-space"> </span>My understanding is that Christopher has patches in <span class="Apple-converted-space"> </span></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">progress to add this to clang, but I'm not sure what the state of <span class="Apple-converted-space"> </span></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">these is.<span class="Apple-converted-space"> </span>It would be great to get have help getting this into clang.</div><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; ">-Chris</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">_______________________________________________</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">LLVM Developers mailing list</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><a href="mailto:LLVMdev@cs.uiuc.edu">LLVMdev@cs.uiuc.edu</a> <span class="Apple-converted-space"> </span><a href="http://llvm.cs.uiuc.edu">http://llvm.cs.uiuc.edu</a></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev</a></div><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; ">_______________________________________________</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">LLVM Developers mailing list</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><a href="mailto:LLVMdev@cs.uiuc.edu">LLVMdev@cs.uiuc.edu</a> <span class="Apple-converted-space"> </span><a href="http://llvm.cs.uiuc.edu">http://llvm.cs.uiuc.edu</a></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev</a></div> </blockquote></div><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; "><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><div><br class="khtml-block-placeholder"></div><br class="Apple-interchange-newline"></span></span> </div><br></body></html>