[PATCH] D127880: [RISCV] Avoid reducing etype just to initialize lane 0 of an undef vector

[Craig Topper via Phabricator via llvm-commits]

craig.topper accepted this revision.
craig.topper added a comment.
This revision is now accepted and ready to land.

LGTM other than the comment about elideCopies.



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Comment at: llvm/lib/Target/RISCV/RISCVInsertVSETVLI.cpp:935
+       (CurInfo.hasZeroAVL() && Require.hasZeroAVL()))) {
+    auto *VRegDef = MRI->getVRegDef(MI.getOperand(1).getReg());
+    if (VRegDef && VRegDef->isImplicitDef() &&
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I wonder if we should call elideCopies here like we do when we look for implicit def for tail policy. 


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