<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 Jonas,<div><br></div><div>Thanks for your patience.</div><div><br></div><div>I have looked into the problem you reported and although the fix you proposed seem correct, I am not sure yet this is the way to go. I would need the debug output of the regalloc to help you further, but here are my initial findings.</div><div><span style="font-family: Calibri, sans-serif; font-size: 11pt;"><br></span></div><div><span style="font-family: Calibri, sans-serif; font-size: 11pt;">traceSiblingValue </span>looked into the problematic phi because the previous iteration said that <span style="font-family: 'Courier New'; font-size: 11pt;">%vreg87:6 </span>and <span style="font-family: 'Courier New'; font-size: 11pt;">%vreg87:5 </span>are sibling.</div><div>Since they are sibling it means they share the same original vreg.</div><div>The problem is that if vreg87:5, i.e., the original phi, is not the original value then it must have been inserted by splitting.</div><div>Based on what you said this is not the case, so we end up in this weird situation.</div><div><br></div><div>If you cannot share the debug output, you could check the following for me:</div><div>1. how vreg76 gets split?</div><div>2. what is the second non-phi/defs for vreg87:5?</div><div>3. if vreg87:5 is not inserted by splitting, how does it gets here?</div><div><br></div><div>Thanks,</div><div>-Quentin</div><div><br></div><div><br></div><div><div><div>On Nov 21, 2014, at 9:22 AM, Jonas Paulsson <<a href="mailto:jonas.paulsson@ericsson.com">jonas.paulsson@ericsson.com</a>> wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div lang="EN-US" link="blue" vlink="purple" style="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 class="WordSection1" style="page: WordSection1;"><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);">Hi Quentin,<o:p></o:p></span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);"> </span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);">I have tried to find a test case for an official target, but failed. It seems to be a rare case.<o:p></o:p></span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);"> </span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);">To do it, I added the ‘else’ clause in the following:<o:p></o:p></span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);"> </span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);">…<o:p></o:p></span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: 'Courier New'; color: rgb(31, 73, 125);">if (VNI->def == OrigVNI->def) {<o:p></o:p></span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: 'Courier New'; color: rgb(31, 73, 125);"> DEBUG(dbgs() << "orig phi value\n");<o:p></o:p></span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: 'Courier New'; color: rgb(31, 73, 125);"> SVI->second.DefByOrigPHI = true;<o:p></o:p></span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: 'Courier New'; color: rgb(31, 73, 125);"> SVI->second.AllDefsAreReloads = false;<o:p></o:p></span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: 'Courier New'; color: rgb(31, 73, 125);"> propagateSiblingValue(SVI);<o:p></o:p></span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: 'Courier New'; color: rgb(31, 73, 125);"> continue;<o:p></o:p></span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: 'Courier New'; color: rgb(31, 73, 125);">}<o:p></o:p></span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);"> //</span><span style="font-size: 11pt; font-family: 'Courier New'; color: rgb(31, 73, 125);"><span class="Apple-converted-space"> </span>check if the valno is actually an orig PHI, but is not OrigVNI<o:p></o:p></span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: 'Courier New'; color: rgb(31, 73, 125);">else {<o:p></o:p></span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: 'Courier New'; color: rgb(31, 73, 125);"> LiveInterval &OrigLI = LIS.getInterval(Original);<o:p></o:p></span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: 'Courier New'; color: rgb(31, 73, 125);"> VNInfo *OrigVNI_curr = OrigLI.getVNInfoAt(VNI->def);<o:p></o:p></span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: 'Courier New'; color: rgb(31, 73, 125);"> if (OrigVNI_curr->def == VNI->def)<o:p></o:p></span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: 'Courier New'; color: rgb(31, 73, 125);"> assert(0 && "OrigLI contained VNI which was a PHI, but not OrigVNI!");<o:p></o:p></span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: 'Courier New'; color: rgb(31, 73, 125);">}<o:p></o:p></span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);"> </span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);">, but the assert never triggered anywhere else than in my original case.<o:p></o:p></span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);"> </span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);">When I did the following, at least my test case worked correctly:<o:p></o:p></span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: 'Courier New'; color: rgb(31, 73, 125);"> </span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: 'Courier New'; color: rgb(31, 73, 125);">LiveInterval &OrigLI = LIS.getInterval(Original);<o:p></o:p></span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: 'Courier New'; color: rgb(31, 73, 125);">VNInfo *OrigVNI_curr = OrigLI.getVNInfoAt(VNI->def);<o:p></o:p></span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: 'Courier New'; color: rgb(31, 73, 125);">if (OrigVNI_curr->def == VNI->def) {<o:p></o:p></span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: 'Courier New'; color: rgb(31, 73, 125);"> DEBUG(dbgs() << "orig phi value\n");<o:p></o:p></span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: 'Courier New'; color: rgb(31, 73, 125);"> SVI->second.DefByOrigPHI = true;<o:p></o:p></span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: 'Courier New'; color: rgb(31, 73, 125);"> SVI->second.AllDefsAreReloads = false;<o:p></o:p></span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: 'Courier New'; color: rgb(31, 73, 125);"> propagateSiblingValue(SVI);<o:p></o:p></span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: 'Courier New'; color: rgb(31, 73, 125);"> continue;<o:p></o:p></span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: 'Courier New'; color: rgb(31, 73, 125);">}<o:p></o:p></span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);"> </span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);">The question is: is this sound and safe?<o:p></o:p></span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);"><o:p></o:p></span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);">It seems logical to me, but I would really appreciate some expert advice,<o:p></o:p></span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);"> </span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);">Jonas<o:p></o:p></span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);"> </span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);"> </span></div><div><div style="border-style: solid none none; border-top-color: rgb(181, 196, 223); border-top-width: 1pt; padding: 3pt 0cm 0cm;"><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><b><span style="font-size: 10pt; font-family: Tahoma, sans-serif;">From:</span></b><span style="font-size: 10pt; font-family: Tahoma, sans-serif;"><span class="Apple-converted-space"> </span>Quentin Colombet [<a href="mailto:qcolombet@apple.com">mailto:qcolombet@apple.com</a>]<span class="Apple-converted-space"> </span><br><b>Sent:</b><span class="Apple-converted-space"> </span>den 18 november 2014 20:19<br><b>To:</b><span class="Apple-converted-space"> </span>Jonas Paulsson<br><b>Cc:</b><span class="Apple-converted-space"> </span><a href="mailto:llvmdev@cs.uiuc.edu">llvmdev@cs.uiuc.edu</a>; <a href="mailto:stoklund@2pi.dk">stoklund@2pi.dk</a><br><b>Subject:</b><span class="Apple-converted-space"> </span>Re: [LLVMdev] InlineSpiller.cpp bug?<o:p></o:p></span></div></div></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><o:p> </o:p></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;">Hi Jonas,<o:p></o:p></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><o:p> </o:p></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;">Could you share your test case and/or file a PR?<o:p></o:p></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><o:p> </o:p></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;">I’d like to see what is going on dynamically to help you.<o:p></o:p></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><o:p> </o:p></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;">Thanks,<o:p></o:p></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;">-Quentin<o:p></o:p></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><o:p> </o:p></div><div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;">On Nov 18, 2014, at 3:26 AM, Jonas Paulsson <<a href="mailto:jonas.paulsson@ericsson.com" style="color: purple; text-decoration: underline;">jonas.paulsson@ericsson.com</a>> wrote:<o:p></o:p></div></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><br><br><o:p></o:p></div><div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;">Hi,<o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;"> <o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;">I have encountered a test case where InlineSpiller generates bad code. A register is reloaded but never spilled, and I suspect a bug in InlineSpiller.<o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;"> <o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;">A register is live over a loop that also have two inner loops. It is not used or defined over the inner loops. It is split into two sibling registers, where one covers just the inner loops interval, which is then spilled.<o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;"> <o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;">In spill(), analyzeSiblingValues() is called, which calls traceSiblingValue(). It traces in several iterations strangely back to the same register (inside a loop), finds it marked to be spilled, and the spill is cancelled:<o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;"> <o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span lang="SV" style="font-size: 11pt; font-family: 'Courier New';">Inline spilling %vreg86 [1396r,2276r:0) 0@1396r</span><span style="font-size: 11pt; font-family: Calibri, sans-serif;"><o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: 'Courier New';">From original %vreg76</span><span style="font-size: 11pt; font-family: Calibri, sans-serif;"><o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: 'Courier New';">Tracing value %vreg86:0@1396r</span><span style="font-size: 11pt; font-family: Calibri, sans-serif;"><o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: 'Courier New';"> %vreg86:0@1396r: copy of %vreg87:6@1168r kill=1</span><span style="font-size: 11pt; font-family: Calibri, sans-serif;"><o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: 'Courier New';"> %vreg87:6@1168r: copy of %vreg87:5@1120B kill=1</span><span style="font-size: 11pt; font-family: Calibri, sans-serif;"><o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: 'Courier New';"> %vreg87:5@1120B: split phi value, checking 1 phi-defs, and 2 non-phi/orig defs</span><span style="font-size: 11pt; font-family: Calibri, sans-serif;"><o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: 'Courier New';"> %vreg87:7@2276r: copy of %vreg86:0@1396r kill=1</span><span style="font-size: 11pt; font-family: Calibri, sans-serif;"><o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: 'Courier New';"> traced to: spill %vreg86:0@1396r all-reloads kill deps[ 7@2276r ]</span><span style="font-size: 11pt; font-family: Calibri, sans-serif;"><o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: 'Courier New';">Merged spilled regs: SS#1 [1396r,2276r:0) 0@x</span><span style="font-size: 11pt; font-family: Calibri, sans-serif;"><o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;"> <o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;">I am guessing that traceSiblingValue() should have stopped at a PHI ValNo by recognizing it as ‘original’, meaning it was not inserted by splitting. It does not although it is clear that this PHI ValNo is part of OrigLI.<o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;"> <o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;">This is how it looked, roughly:<o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;"> <o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;">Original LiveInterval:<o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;">5 0 --- inner loops --- // last valno in interval<o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;">PHI COPY of valno 5<o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;"> <o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;">After splitting:<o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;">5 6 7 8<o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;">PHI COPY of valno 5 COPY of valno 0 PHI<o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;"> 0<o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;"> COPY of valno 6<o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;"> /\<o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;"> OrigVNI<o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;"> <o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;">Tracing sibling values, valno 6 is the original valno:<o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;">Valno 0 is a copy from 6.<o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;">Valno 6 is a copy from 5.<o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;">Valno 5 is a phi. Is it OrigVNI? NO! ‘Therefore it is not an original phi.’ WRONG! The search continues past it, assuming that it is a newly inserted PHI, done during splitting.<o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;"> <o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;">My conlusion is that either the line<o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;"> <o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: 'Courier New';">if (VNI->def == OrigVNI->def)</span><span style="font-size: 11pt; font-family: Calibri, sans-serif;"><o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;"> <o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;">is wrong, because it doesn’t really check that VNI was not a phi in OrigLI, because it assumes that if VNI is a phi which was part of the original LI, then OrigVNI must be that PHI. This is not the case here.<o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;">The algorithm has iterated past OrigVNI and VNI is at this point a phi that was part of the original LI, which is the copy source of OrigVNI.<o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;"> <o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;">Or, it is assumed that splitting is always done at PHI ValNos somehow, and not as in this case, by a COPY of a PHI ValNo.<o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;"> <o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;">I would very much appreciate assistance in resolving this problem. As explained above, it is not clear to me why this error occurs, or what is the appropriate fix. I can provide more details if needed for some reason.<o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;"> <o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;">Best regards,<o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;"> <o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;">Jonas Paulsson<o:p></o:p></span></div></div><div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 11pt; font-family: Calibri, sans-serif;"> <o:p></o:p></span></div></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 9pt; font-family: Helvetica, sans-serif;">_______________________________________________<br>LLVM Developers mailing list<br><a href="mailto:LLVMdev@cs.uiuc.edu" style="color: purple; text-decoration: underline;"><span style="color: purple;">LLVMdev@cs.uiuc.edu</span></a><span class="apple-converted-space"> </span> <a href="http://llvm.cs.uiuc.edu/" style="color: purple; text-decoration: underline;"><span style="color: purple;">http://llvm.cs.uiuc.edu</span></a><br><a href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev" style="color: purple; text-decoration: underline;"><span style="color: purple;">http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev</span></a></span></div></div></div></div></div></div></blockquote></div><br></div></body></html>