[PATCH] D99412: [AArch64][SVEIntrinsicOpts] Optimize tbl+dup into dup+extractelement

[Paul Walker via Phabricator via llvm-commits]

paulwalker-arm added inline comments.


================
Comment at: llvm/lib/Target/AArch64/SVEIntrinsicOpts.cpp:466-467
+  auto *Extract = Builder.CreateExtractElement(OpVal, SplatValue);
+  auto *NewDupX =
+      Builder.CreateIntrinsic(Intrinsic::aarch64_sve_dup_x, {VTy}, {Extract});
+
----------------
Can you use `Builder.CreateVectorSplat` here?


================
Comment at: llvm/lib/Target/AArch64/SVEIntrinsicOpts.cpp:469-470
+
+  I->replaceAllUsesWith(NewDupX);
+  I->eraseFromParent();
+  return true;
----------------
I'm never really sure what to do in these instances but do we need to worry about the original DupXIntrI?  Given we know its operand is constant it's easily removed if this was the only use.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D99412/new/

https://reviews.llvm.org/D99412