[PATCH] D53257: [ARM][NEON] Improve vector popcnt lowering with PADDL (PR39281)

[Simon Pilgrim via Phabricator via llvm-commits]

RKSimon added inline comments.


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Comment at: lib/Target/ARM/ARMISelLowering.cpp:5454
+    SmallVector<SDValue, 8> Ops;
+    Ops.push_back(DAG.getConstant(Intrinsic::arm_neon_vpaddlu, DL,
+                                  TLI.getPointerTy(DAG.getDataLayout())));
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samparker wrote:
> For the 64-bit vector case, couldn't we use vpadd instead? We don't care about signed/unsigned, but we'd have to know that the wide result isn't necessary too - which I expect is fine for most bit counting cases.
Sorry, I don't quite understand - please can you show in the test codegen what you're trying to achieve?


Repository:
  rL LLVM

https://reviews.llvm.org/D53257