<html><head><meta http-equiv="Content-Type" content="text/html charset=windows-1252"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;">Hi Oliver,<div><br></div><div>There are several things you can do to at least isolate which part of the compiler is at “fault”.</div><div>1. Try to compile with -E to produce the preprocess file.</div><div>2. Try to compile the preprocess file with -O0 -emit-llvm -S -o file.ll to produce the llvm-ir.</div><div>3. Try to compile the llvm-ir file with opt with your optimization level to see if it is the high level optimizations passes. (e.g., opt -O3 file.ll -S -o after_opt.ll).</div><div>4. Try to compile the produced after_opt.ll with llc to see if it is a low-level optimization problem, e.g. llc after_opt.ll -o out.s -O3.</div><div><br></div><div>Hopefully, one of this step will take a lot of time and will be the faulty part.</div><div>When you have that, filing a bug would be the right thing to do. </div><div><br></div><div>Thanks,</div><div><div apple-content-edited="true">
<div style="color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">-Quentin</div>
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<br><div><div>On Jan 29, 2014, at 11:00 AM, Oliver Schneider <<a href="mailto:oliver@f-prot.com">oliver@f-prot.com</a>> wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite">A colleague of mine wrote some test cases in a single huge C file with a<br>lot of macros.<br><br>GCC takes a few seconds to compile the file, but Clang takes apparently<br>more than 10 minutes - I canceled it at that point.<br><br>How can I track down the problem? I guess C-Reduce won't cut it this<br>time, because it's a performance problem.<br><br>Thanks,<br><br>// Oliver<br><br>_______________________________________________<br>cfe-dev mailing list<br><a href="mailto:cfe-dev@cs.uiuc.edu">cfe-dev@cs.uiuc.edu</a><br>http://lists.cs.uiuc.edu/mailman/listinfo/cfe-dev<br></blockquote></div><br></div></body></html>