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<p class="MsoNormal">Still diving into LLVM… I noticed that the LLVM type system does not represent qualifers (const, volatile, restrict).<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">From what I can gather, <o:p></o:p></p>
<p class="MsoNormal"> - the back end cannot ignore volatile, so loads/stores are annotated as volatile when they load/store through a volatile qualified pointer.<o:p></o:p></p>
<p class="MsoNormal">- const qualifiers are noted in metadata (I think)<o:p></o:p></p>
<p class="MsoNormal">- top level restrict qualified function parameters are marked with a ‘noalias’ attribute<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">So it appears that the restrict-ness of global/local pointers are not represented in LLVM, and thus ignored.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">For example,<o:p></o:p></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:Courier">{<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:Courier"> int * restrict p2 = p1;</span><i><span style="font-size:10.0pt;font-family:"Times New Roman","serif""><o:p></o:p></span></i></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:Courier"> int * restrict q2 = q1;<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:Courier"> ...<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:Courier">}<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Are there plans to add this (primarily to improve loop based alias analysis)?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">And I’m just curious, what’s the design philosophy behind not representing qualifiers in the LLVM type system? Were their semantics considered too language specific?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks<o:p></o:p></p>
<p class="MsoNormal">Jon<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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