<html><head><meta http-equiv="Content-Type" content="text/html charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><br class=""><div><blockquote type="cite" class=""><div class="">On Jun 15, 2015, at 7:05 AM, Ryan Taylor <<a href="mailto:ryta1203@gmail.com" class="">ryta1203@gmail.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div dir="ltr" class=""><div class="">To be more specific:</div><div class=""><br class=""></div><div class="">We have some operators that we are currently implementing as intrinsics, for example things like: abs, min, max, etc.....</div><div class=""><br class=""></div><div class="">for some code:</div><div class=""><br class=""></div><div class="">int a;</div><div class=""><br class=""></div><div class="">int food() </div><div class="">{</div><div class=""> return abs(a);</div><div class="">}</div><div class=""><br class=""></div><div class="">the corresponding operator should look something like:</div><div class=""><br class=""></div><div class="">abs $a, r0</div><div class=""><br class=""></div><div class="">however, it looks like since intrinsics are handled as 'calls', we end up with something like:</div><div class=""><br class=""></div><div class="">mov $a, r0</div><div class="">abs r0, r0</div><div class=""><br class=""></div><div class="">Would it be better to make 'abs' an operator as opposed to an intrinsic, or is it possible in LLVM to support direct mem loads/stores via intrinsics?</div><div class=""><br class=""></div><div class="">I realize that we could resolve this with some peephole opts, I just want to know if there is a way in LLVM to get the 'abs $a, r0' match directly through tblgen?</div></div></div></blockquote><div><br class=""></div><div><br class=""></div><div>I assume that what you mean by “operator” is called “machine instruction” in LLVM. </div><div>It seems from the snippet you show "abs r0, r0” that the intrinsic call is correctly turned into a native instruction and not a runtime call, so the intrinsic is somehow matched.</div><div><br class=""></div><div>What pattern have you tried to match the sequence abs(load(x)) in tblgen?</div><div>If you try to grep for “load” in the X86 backend tblgen files you should find examples of pattern.</div><div><br class=""></div><div><br class=""></div><div>— </div><div>Mehdi</div><div><br class=""></div><br class=""><blockquote type="cite" class=""><div class=""><div dir="ltr" class=""><div class=""><br class=""></div><div class="">Thanks.</div></div><div class="gmail_extra"><br class=""><div class="gmail_quote">On Wed, Jun 10, 2015 at 8:19 PM, Ryan Taylor <span dir="ltr" class=""><<a href="mailto:ryta1203@gmail.com" target="_blank" class="">ryta1203@gmail.com</a>></span> wrote:<br class=""><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr" class=""><div class="">What's the best way to get direct memory accesses for intrinsics via tblgen?</div><div class=""><br class=""></div><div class="">We have some instructions represented as intrinsics. These instructions allow direct memory access, I've tried multiclasses but they won't match. I've also tried "def : Pat<....> but it won't recognize the complex pattern as a valid operand?</div><div class=""><br class=""></div><div class="">Thanks.</div></div>
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