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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">How is this different from the work that Hal has been doing:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><a href="https://reviews.llvm.org/search/query/qa3.P4sG6bA8/#R">https://reviews.llvm.org/search/query/qa3.P4sG6bA8/#R</a><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><a href="https://llvm.org/devmtg/2017-02-04/Restrict-Qualified-Pointers-in-LLVM.pdf">https://llvm.org/devmtg/2017-02-04/Restrict-Qualified-Pointers-in-LLVM.pdf</a><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> llvm-dev [mailto:llvm-dev-bounces@lists.llvm.org]
<b>On Behalf Of </b>Alexandre Mutel via llvm-dev<br>
<b>Sent:</b> Thursday, September 14, 2017 4:34 AM<br>
<b>To:</b> llvm-dev@lists.llvm.org<br>
<b>Subject:</b> [llvm-dev] [RFC] noalias intrinsic<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p><span style="font-family:"Calibri","sans-serif";color:black">Hello,<o:p></o:p></span></p>
<p><span style="font-family:"Calibri","sans-serif";color:black"><o:p> </o:p></span></p>
<p><span style="font-family:"Calibri","sans-serif";color:black">Currently the noalias attribute can be applied on function parameters and return value, or via scoped alias on store.<o:p></o:p></span></p>
<p><span style="font-family:"Calibri","sans-serif";color:black">The problem is that there is no easy way to apply the noalias attribute on a pointer that is loaded indirectly (e.g from the field of an aggregate, or from a memory location - though for this you
can still use scoped alias, but they are a lot more intrusive)<o:p></o:p></span></p>
<p><span style="font-family:"Calibri","sans-serif";color:black"><o:p> </o:p></span></p>
<p><span style="font-family:"Calibri","sans-serif";color:black">The idea would be to provide some kind of intrinsic that can transform a pointer to a noalias pointer, something in the lines of:<o:p></o:p></span></p>
<p><span style="font-family:"Calibri","sans-serif";color:black"><o:p> </o:p></span></p>
<p><span style="font-family:"Calibri","sans-serif";color:black">define noalias i32* @noalias(i32 *%a) {<o:p></o:p></span></p>
<p><span style="font-family:"Calibri","sans-serif";color:black"> ret i32* %a<o:p></o:p></span></p>
<p><span style="font-family:"Calibri","sans-serif";color:black">}<o:p></o:p></span></p>
<p><span style="font-family:"Calibri","sans-serif";color:black"><o:p> </o:p></span></p>
<p><span style="font-family:"Calibri","sans-serif";color:black">What do you think? Would it fit an intrinsic?<o:p></o:p></span></p>
<p><span style="font-family:"Calibri","sans-serif";color:black"><o:p> </o:p></span></p>
<p><span style="font-family:"Calibri","sans-serif";color:black">Alexandre<o:p></o:p></span></p>
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