<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="">From this message it looks like the vectorizer is having some general problems with the testcase. I’d suggest to try the simplest case for the beginning, just to make sure vectorizer works. Like this:<div class="">void foo(int *a, int *b, int *c) {</div><div class=""> int i;<br class=""><div class=""> for(i = 0; i < 1000; i++) {</div><div class=""> a[i] = b[i] + c[i];</div><div class=""> }</div><div class="">}</div><div class=""><br class=""></div><div class="">If you compile it with ‘clang -O3 -arch arm64 -S’, you should see the SIMD instructions. If you do see them, it means that your original test is too complicated for the vectorizer right now (that might be due to some bug) - feel free to file a bug.</div><div class=""><br class=""></div><div class="">Thanks,</div><div class="">Michael</div><div class=""><div class=""><br class=""></div><div class=""><br class=""><div><blockquote type="cite" class=""><div class="">On Feb 9, 2015, at 3:33 PM, Ralph Campbell <<a href="mailto:ralph.campbell@broadcom.com" class="">ralph.campbell@broadcom.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div class="WordSection1" style="page: WordSection1; font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;"><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);" class="">% clang -S -O3 -mcpu=cortex-a57 -ffast-math -Rpass-analysis=loop-vectorize dot.c<o:p class=""></o:p></span></div><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);" class="">dot.c:15:1: remark: loop not vectorized: value that could not be identified as<o:p class=""></o:p></span></div><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);" class=""> reduction is used outside the loop [-Rpass-analysis=loop-vectorize]<o:p class=""></o:p></span></div><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);" class="">}<o:p class=""></o:p></span></div><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);" class="">^<o:p class=""></o:p></span></div><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);" class="">dot.c:15:1: note: could not determine the original source location for :0:0<o:p class=""></o:p></span></div><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);" class=""> </span></div><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);" class="">I found “llvm-as < /dev/null | llc -march=aarch64 -mattr=help” which listed a bunch of features but when I tried<o:p class=""></o:p></span></div><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);" class="">adding “-mfpu=neon” or “-mattr=+neon”, clang complained that the option was unrecognized.<o:p class=""></o:p></span></div><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);" class=""> </span></div><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);" class=""> </span></div><div class=""><div style="border-style: solid none none; border-top-color: rgb(181, 196, 223); border-top-width: 1pt; padding: 3pt 0in 0in;" class=""><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><b class=""><span style="font-size: 10pt; font-family: Tahoma, sans-serif;" class="">From:</span></b><span style="font-size: 10pt; font-family: Tahoma, sans-serif;" class=""><span class="Apple-converted-space"> </span>Michael Zolotukhin [<a href="mailto:mzolotukhin@apple.com" style="color: purple; text-decoration: underline;" class="">mailto:mzolotukhin@apple.com</a>]<span class="Apple-converted-space"> </span><br class=""><b class="">Sent:</b><span class="Apple-converted-space"> </span>Monday, February 09, 2015 3:08 PM<br class=""><b class="">To:</b><span class="Apple-converted-space"> </span>Ralph Campbell<br class=""><b class="">Cc:</b><span class="Apple-converted-space"> </span>Arnaud A. de Grandmaison;<span class="Apple-converted-space"> </span><a href="mailto:llvmdev@cs.uiuc.edu" style="color: purple; text-decoration: underline;" class="">llvmdev@cs.uiuc.edu</a><br class=""><b class="">Subject:</b><span class="Apple-converted-space"> </span>Re: [LLVMdev] aarch64 status for generating SIMD instructions<o:p class=""></o:p></span></div></div></div><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><o:p class=""> </o:p></div><div class=""><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class="">Hi Ralph,<o:p class=""></o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><o:p class=""> </o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class="">A bunch of useful options for vectorizers is listed in [1].<o:p class=""></o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><o:p class=""> </o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class="">Also, what you see might be a target-independent issue, not an aarch64-specific. If you can share the code you tested I can try to explain why vectorizer fails to handle it, and hopefully we can fix it later:)<o:p class=""></o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><o:p class=""> </o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class="">Thanks,<o:p class=""></o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class="">Michael<o:p class=""></o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><o:p class=""> </o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class="">[1] <a href="http://llvm.org/docs/Vectorizers.html" style="color: purple; text-decoration: underline;" class="">http://llvm.org/docs/Vectorizers.html</a><o:p class=""></o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><o:p class=""> </o:p></div></div><div class=""><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><o:p class=""> </o:p></div></div><div class=""><blockquote style="margin-top: 5pt; margin-bottom: 5pt;" class=""><div class=""><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class="">On Feb 9, 2015, at 2:19 PM, Ralph Campbell <<a href="mailto:ralph.campbell@broadcom.com" style="color: purple; text-decoration: underline;" class="">ralph.campbell@broadcom.com</a>> wrote:<o:p class=""></o:p></div></div><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><o:p class=""> </o:p></div><div class=""><div class=""><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);" class="">So far, all I have tried is –O3 and with & without “-mcpu=cortex-a57”.</span><span style="font-size: 11pt; font-family: Calibri, sans-serif;" class=""><o:p class=""></o:p></span></div></div><div class=""><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);" class="">I’m new to LLVM so I’m not familiar with what optimization flags are available.</span><span style="font-size: 11pt; font-family: Calibri, sans-serif;" class=""><o:p class=""></o:p></span></div></div><div class=""><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);" class="">I tried poking around in the LLVM documentation but haven’t found a definitive list.</span><span style="font-size: 11pt; font-family: Calibri, sans-serif;" class=""><o:p class=""></o:p></span></div></div><div class=""><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);" class="">The clang man page is skimpy on details.</span><span style="font-size: 11pt; font-family: Calibri, sans-serif;" class=""><o:p class=""></o:p></span></div></div><div class=""><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);" class=""> </span><span style="font-size: 11pt; font-family: Calibri, sans-serif;" class=""><o:p class=""></o:p></span></div></div><div class=""><div style="border-style: solid none none; border-top-color: rgb(181, 196, 223); border-top-width: 1pt; padding: 3pt 0in 0in;" class=""><div class=""><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><b class=""><span style="font-size: 10pt; font-family: Tahoma, sans-serif;" class="">From:</span></b><span class="apple-converted-space"><span style="font-size: 10pt; font-family: Tahoma, sans-serif;" class=""> </span></span><span style="font-size: 10pt; font-family: Tahoma, sans-serif;" class="">Arnaud A. de Grandmaison [<a href="mailto:arnaud.degrandmaison@arm.com" style="color: purple; text-decoration: underline;" class="">mailto:arnaud.degrandmaison@arm.com</a>]<span class="apple-converted-space"> </span><br class=""><b class="">Sent:</b><span class="apple-converted-space"> </span>Monday, February 09, 2015 2:11 PM<br class=""><b class="">To:</b><span class="apple-converted-space"> </span>Ralph Campbell<br class=""><b class="">Cc:</b><span class="apple-converted-space"> </span><a href="mailto:llvmdev@cs.uiuc.edu" style="color: purple; text-decoration: underline;" class="">llvmdev@cs.uiuc.edu</a><br class=""><b class="">Subject:</b><span class="apple-converted-space"> </span>RE: aarch64 status for generating SIMD instructions</span><span style="font-size: 11pt; font-family: Calibri, sans-serif;" class=""><o:p class=""></o:p></span></div></div></div></div><div class=""><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><span style="font-size: 11pt; font-family: Calibri, sans-serif;" class=""> <o:p class=""></o:p></span></div></div><div class=""><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><span lang="EN-GB" style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);" class="">Which compiler flags have you been using ?</span><span style="font-size: 11pt; font-family: Calibri, sans-serif;" class=""><o:p class=""></o:p></span></div></div><div class=""><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><span lang="EN-GB" style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);" class=""> </span><span style="font-size: 11pt; font-family: Calibri, sans-serif;" class=""><o:p class=""></o:p></span></div></div><div class=""><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><span lang="EN-GB" style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);" class="">There is definitely support for AArch64’s SIMD instructions, but their use depends on what the vectorizers can do with your code.</span><span style="font-size: 11pt; font-family: Calibri, sans-serif;" class=""><o:p class=""></o:p></span></div></div><div class=""><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><span lang="EN-GB" style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);" class=""> </span><span style="font-size: 11pt; font-family: Calibri, sans-serif;" class=""><o:p class=""></o:p></span></div></div><div style="border-style: none none none solid; border-left-color: blue; border-left-width: 1.5pt; padding: 0in 0in 0in 4pt;" class=""><div class=""><div style="border-style: solid none none; border-top-color: rgb(181, 196, 223); border-top-width: 1pt; padding: 3pt 0in 0in;" class=""><div class=""><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><b class=""><span style="font-size: 10pt; font-family: Tahoma, sans-serif;" class="">From:</span></b><span class="apple-converted-space"><span style="font-size: 10pt; font-family: Tahoma, sans-serif;" class=""> </span></span><span style="font-size: 10pt; font-family: Tahoma, sans-serif;" class=""><a href="mailto:llvmdev-bounces@cs.uiuc.edu" style="color: purple; text-decoration: underline;" class=""><span style="color: purple;" class="">llvmdev-bounces@cs.uiuc.edu</span></a><span class="apple-converted-space"> </span>[<a href="mailto:llvmdev-bounces@cs.uiuc.edu" style="color: purple; text-decoration: underline;" class=""><span style="color: purple;" class="">mailto:llvmdev-bounces@cs.uiuc.edu</span></a>]<span class="apple-converted-space"> </span><b class="">On Behalf Of<span class="apple-converted-space"> </span></b>Ralph Campbell<br class=""><b class="">Sent:</b><span class="apple-converted-space"> </span>09 February 2015 22:30<br class=""><b class="">To:</b><span class="apple-converted-space"> </span><a href="mailto:llvmdev@cs.uiuc.edu" style="color: purple; text-decoration: underline;" class=""><span style="color: purple;" class="">llvmdev@cs.uiuc.edu</span></a><br class=""><b class="">Subject:</b><span class="apple-converted-space"> </span>[LLVMdev] aarch64 status for generating SIMD instructions</span><span style="font-size: 11pt; font-family: Calibri, sans-serif;" class=""><o:p class=""></o:p></span></div></div></div></div><div class=""><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><span lang="EN-GB" style="font-size: 11pt; font-family: Calibri, sans-serif;" class=""> </span><span style="font-size: 11pt; font-family: Calibri, sans-serif;" class=""><o:p class=""></o:p></span></div></div><div class=""><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><span style="font-size: 11pt; font-family: Calibri, sans-serif;" class="">I’m using Fedora 22 and gcc 4.9.2 to run llvm 3.5.1 on an ARM Juno reference box (cortex A53 & A57).<o:p class=""></o:p></span></div></div><div class=""><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><span style="font-size: 11pt; font-family: Calibri, sans-serif;" class="">I tried compiling some simple functions like dot product and axpy() into assembly to see if any of the SIMD instructions were generated (they weren’t).<o:p class=""></o:p></span></div></div><div class=""><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><span style="font-size: 11pt; font-family: Calibri, sans-serif;" class="">Perhaps I’m missing some compiler flag to enable it.<o:p class=""></o:p></span></div></div><div class=""><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><span style="font-size: 11pt; font-family: Calibri, sans-serif;" class=""> <o:p class=""></o:p></span></div></div><div class=""><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><span style="font-size: 11pt; font-family: Calibri, sans-serif;" class="">Does anyone know what the status is for aarch64 generating SIMD instructions?<o:p class=""></o:p></span></div></div><div class=""><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><span style="font-size: 11pt; font-family: Calibri, sans-serif;" class="">Anyone coordinating or leading this effort? (if there is one)<o:p class=""></o:p></span></div></div></div><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><span style="font-size: 9pt; font-family: Helvetica, sans-serif;" class="">_______________________________________________<br class="">LLVM Developers mailing list<br class=""><a href="mailto:LLVMdev@cs.uiuc.edu" style="color: purple; text-decoration: underline;" class="">LLVMdev@cs.uiuc.edu</a><span class="Apple-converted-space"> </span> <a href="http://llvm.cs.uiuc.edu/" style="color: purple; text-decoration: underline;" class="">http://llvm.cs.uiuc.edu</a><br class=""><a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev" style="color: purple; text-decoration: underline;" class="">http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev</a></span><o:p class=""></o:p></div></div></blockquote></div><div style="margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><o:p class=""> </o:p></div></div><span id="cid:FFC49321-DAF4-40DA-9D1D-AE12DB02D0CF@apple.com"><dot.s></span><span id="cid:4DF79AC0-24AD-498E-B892-6DD6A0A81CCB@apple.com"><dot.c></span></div></blockquote></div><br class=""></div></div></div></body></html>