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<p class="MsoNormal"><span lang="DE-AT" style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Hi Sam,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="DE-AT" 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">thanks for the info! I will have a look at the vararg_ty. Maybe I could also use an intrinsic to just mark the call instruction.<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">Regards<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">Felix<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 lang="DE" style="font-size:11.0pt;font-family:"Calibri",sans-serif">Von:</span></b><span lang="DE" style="font-size:11.0pt;font-family:"Calibri",sans-serif"> Sam Parker <Sam.Parker@arm.com>
<br>
<b>Gesendet:</b> Freitag, 27. März 2020 14:03<br>
<b>An:</b> Felix Berlakovich <felix@berlakovich.at>; llvm-dev@lists.llvm.org<br>
<b>Betreff:</b> Re: Passing inormation from pass to lowering<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif;color:black">Hi Felix,<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif;color:black"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif;color:black">I would try to replicate your call with an intrinsic and jump to the trampoline. <span style="background:white">There's a vararg_ty that can be used for your intrinsic type declaration,
but I haven't used it myself.</span><o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif;color:black"><o:p> </o:p></span></p>
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<p style="background:white"><span style="font-family:"Calibri",sans-serif;color:black">Sam Parker</span><span style="color:black"><o:p></o:p></span></p>
<p style="background:white"><span style="font-family:"Calibri",sans-serif;color:black">Compilation Tools Engineer | Arm</span><span style="color:black"><o:p></o:p></span></p>
<p style="background:white"><span style="font-family:"Calibri",sans-serif;color:black">. . . . . . . . . . . . . . . . . . . . . . . . . . .</span><span style="color:black"><o:p></o:p></span></p>
<p style="background:white"><span style="font-family:"Calibri",sans-serif;color:black">Arm.com</span><span style="color:black"><o:p></o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:black">From:</span></b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:black"> Felix Berlakovich <<a href="mailto:felix@berlakovich.at">felix@berlakovich.at</a>><br>
<b>Sent:</b> 27 March 2020 12:54<br>
<b>To:</b> Sam Parker <<a href="mailto:Sam.Parker@arm.com">Sam.Parker@arm.com</a>>;
<a href="mailto:llvm-dev@lists.llvm.org">llvm-dev@lists.llvm.org</a> <<a href="mailto:llvm-dev@lists.llvm.org">llvm-dev@lists.llvm.org</a>><br>
<b>Subject:</b> AW: Passing inormation from pass to lowering</span> <o:p></o:p></p>
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<p class="MsoNormal"> <o:p></o:p></p>
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<p class="xmsonormal"><span lang="DE-AT" style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Hi Sam,</span><o:p></o:p></p>
<p class="xmsonormal"><span lang="DE-AT" style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> </span><o:p></o:p></p>
<p class="xmsonormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">I think an intrinsic would be ideal, but I couldn’t figure out how to replace calls with an arbitrary number of arguments with a call to an intrinsic. In particular,
I would like to call a trampoline instead of the original function. The trampoline performs certain actions and then jumps to the original callee. Would I have to call the intrinsic with the original arguments and then perform a jump to the original function
in the intrinsic?</span><o:p></o:p></p>
<p class="xmsonormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> </span><o:p></o:p></p>
<p class="xmsonormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Inlining is not possible unfortunately. I tried to use a IR branch instruction to jump the trampoline, but then the first basic block of the trampoline has a
predecessor which is not allowed.</span><o:p></o:p></p>
<p class="xmsonormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> </span><o:p></o:p></p>
<p class="xmsonormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Thanks for your help</span><o:p></o:p></p>
<p class="xmsonormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> </span><o:p></o:p></p>
<p class="xmsonormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Felix</span><o:p></o:p></p>
<p class="xmsonormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> </span><o:p></o:p></p>
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<p class="xmsonormal"><b><span lang="DE" style="font-size:11.0pt;font-family:"Calibri",sans-serif">Von:</span></b><span lang="DE" style="font-size:11.0pt;font-family:"Calibri",sans-serif"> Sam Parker <<a href="mailto:Sam.Parker@arm.com">Sam.Parker@arm.com</a>>
<br>
<b>Gesendet:</b> Freitag, 27. März 2020 12:47<br>
<b>An:</b> <a href="mailto:llvm-dev@lists.llvm.org">llvm-dev@lists.llvm.org</a>; Felix Berlakovich <<a href="mailto:felix@berlakovich.at">felix@berlakovich.at</a>><br>
<b>Betreff:</b> Re: Passing inormation from pass to lowering</span><o:p></o:p></p>
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<p class="xmsonormal"> <o:p></o:p></p>
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<p class="xmsonormal"><span style="font-family:"Calibri",sans-serif;color:black">Hi Felix,</span><o:p></o:p></p>
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<p class="xmsonormal"><span style="font-family:"Calibri",sans-serif;color:black"> </span><o:p></o:p></p>
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<p class="xmsonormal"><span style="font-family:"Calibri",sans-serif;color:black">Could you use intrinsics instead? Or modify the IR directly to inline and perform a br instead of a call?</span><o:p></o:p></p>
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<p class="xmsonormal"><span style="font-family:"Calibri",sans-serif;color:black"> </span><o:p></o:p></p>
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<p class="xmsonormal"><span style="font-family:"Calibri",sans-serif;color:black">Regards,</span><o:p></o:p></p>
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<p class="xmsonormal"><span style="font-family:"Calibri",sans-serif;color:black">Sam</span><o:p></o:p></p>
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<p class="xmsonormal"><span style="font-family:"Calibri",sans-serif;color:black"> </span><o:p></o:p></p>
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<p style="background:white"><span style="font-family:"Calibri",sans-serif;color:black">Sam Parker</span><o:p></o:p></p>
<p style="background:white"><span style="font-family:"Calibri",sans-serif;color:black">Compilation Tools Engineer | Arm</span><o:p></o:p></p>
<p style="background:white"><span style="font-family:"Calibri",sans-serif;color:black">. . . . . . . . . . . . . . . . . . . . . . . . . . .</span><o:p></o:p></p>
<p style="background:white"><span style="font-family:"Calibri",sans-serif;color:black">Arm.com</span><o:p></o:p></p>
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<p class="xmsonormal"><b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:black">From:</span></b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:black"> llvm-dev <<a href="mailto:llvm-dev-bounces@lists.llvm.org">llvm-dev-bounces@lists.llvm.org</a>>
on behalf of Felix Berlakovich via llvm-dev <<a href="mailto:llvm-dev@lists.llvm.org">llvm-dev@lists.llvm.org</a>><br>
<b>Sent:</b> 27 March 2020 08:28<br>
<b>To:</b> <a href="mailto:llvm-dev@lists.llvm.org">llvm-dev@lists.llvm.org</a> <<a href="mailto:llvm-dev@lists.llvm.org">llvm-dev@lists.llvm.org</a>><br>
<b>Subject:</b> [llvm-dev] Passing inormation from pass to lowering</span> <o:p></o:p></p>
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<p class="xmsonormal"> <o:p></o:p></p>
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<p class="xxmsonormal">Hi!<o:p></o:p></p>
<p class="xxmsonormal"> <o:p></o:p></p>
<p class="xxmsonormal">I have written a ModulePass that calculates various things and adds custom metadata attributes to certain instructions. Depending on the attributes, I would like to change the machine code of these instructions. For example, I would like
to replace certain calls with jumps, but as far as I can tell the IR metadata is not accessible anymore on the level of machine instructions (e.g. in the AsmPrinter). What is the best way to pass the information calculated by the pass (e.g the attributes)
to the part where the target specific instructions are emitted?<o:p></o:p></p>
<p class="xxmsonormal"> <o:p></o:p></p>
<p class="xxmsonormal">Regards<o:p></o:p></p>
<p class="xxmsonormal"> <o:p></o:p></p>
<p class="xxmsonormal">Felix<o:p></o:p></p>
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