<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 Feb 21, 2017, at 16:39, Friedman, Eli via llvm-commits <<a href="mailto:llvm-commits@lists.llvm.org" class="">llvm-commits@lists.llvm.org</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><span style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: 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; float: none; display: inline !important;" class="">On 2/21/2017 2:47 PM, Matt Arsenault via llvm-commits wrote:</span><br style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: 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;" class=""><blockquote type="cite" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px;" class="">Author: arsenm<br class="">Date: Tue Feb 21 16:47:27 2017<br class="">New Revision: 295782<br class=""><br class="">URL: <a href="http://llvm.org/viewvc/llvm-project?rev=295782&view=rev" class="">http://llvm.org/viewvc/llvm-project?rev=295782&view=rev</a><br class="">Log:<br class="">DAG: Check if extract_vector_elt is legal or custom<br class=""><br class="">Avoids test regressions in future AMDGPU commits when<br class="">more vector types are custom lowered.<br class=""><br class="">Modified:<br class=""> llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp<br class=""><br class="">Modified: llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp<br class="">URL: <a href="http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp?rev=295782&r1=295781&r2=295782&view=diff" class="">http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp?rev=295782&r1=295781&r2=295782&view=diff</a><br class="">==============================================================================<br class="">--- llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp (original)<br class="">+++ llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp Tue Feb 21 16:47:27 2017<br class="">@@ -7882,7 +7882,7 @@ SDValue DAGCombiner::visitTRUNCATE(SDNod<br class=""> EVT SrcVT = VecSrc.getValueType();<br class=""> if (SrcVT.isVector() && SrcVT.getScalarType() == VT &&<br class=""> (!LegalOperations ||<br class="">- TLI.isOperationLegal(ISD::EXTRACT_VECTOR_ELT, SrcVT))) {<br class="">+ TLI.isOperationLegalOrCustom(ISD::EXTRACT_VECTOR_ELT, SrcVT))) {<br class=""> SDLoc SL(N);<br class=""> EVT IdxVT = TLI.getVectorIdxTy(DAG.getDataLayout());<br class=""><br class=""></blockquote><br style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: 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;" class=""><span style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: 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; float: none; display: inline !important;" class="">This doesn't work. If LegalOperations is true, we're creating an operation which isn't legal after the legalizer has run, so a operation marked CUSTOM could fail to match. (For example, on AArch64, we custom-lower EXTRACT_VECTOR_ELT on 64-bit vectors by widening them to 128-bit vectors.)</span><br style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: 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;" class=""><br style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: 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;" class=""><span style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: 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; float: none; display: inline !important;" class="">If you're running into trouble with this, maybe it makes sense to add a specific helper here, along the lines of isShuffleMaskLegal?</span><br style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: 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;" class=""><br style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: 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;" class=""><span style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: 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; float: none; display: inline !important;" class="">-Eli</span><br class=""></div></blockquote><br class=""></div><div>I don’t think that’s true since r214020? The pattern of checking isLegalOrCustom is repeated in a variety of places (I’m not sure we even really want to use isLegal anywhere anymore)</div><div><br class=""></div><div>-Matt</div></body></html>