[PATCH] D138025: [RISCV] Make lowerVECTOR_SHUFFLEAsVSlidedown follow source until not EXTRACT_SUBVECTOR.

[Craig Topper via Phabricator via llvm-commits]

craig.topper added inline comments.


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Comment at: llvm/lib/Target/RISCV/RISCVISelLowering.cpp:2948
+           Parent.getOperand(0).getSimpleValueType().isFixedLengthVector()) {
+      Idx.push_back(Parent.getConstantOperandVal(1));
+      Parent = Parent.getOperand(0);
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Can we accumulate the indices into a single value here instead of putting them in a vector?


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Comment at: llvm/lib/Target/RISCV/RISCVISelLowering.cpp:2969
+    auto [RebuildIndex, StartOffset] =
+        static_cast<uint64_t>(NewMask[i]) < NewMask.size()
+            ? std::make_pair(ArrayRef<uint64_t>(V1Index),
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unsigned is probably sufficient. I don't think you need uint64_t


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Comment at: llvm/lib/Target/RISCV/RISCVISelLowering.cpp:2970
+        static_cast<uint64_t>(NewMask[i]) < NewMask.size()
+            ? std::make_pair(ArrayRef<uint64_t>(V1Index),
+                             static_cast<size_t>(0))
----------------
Use makeArrayRef


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Comment at: llvm/lib/Target/RISCV/RISCVISelLowering.cpp:2972
+                             static_cast<size_t>(0))
+            : std::make_pair(ArrayRef<uint64_t>(V2Index), NewMask.size());
+    // StartOffset is needed. Otherwise, the b case would be <5,6,7,12> instead
----------------
makeArrayRef


Repository:
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  https://reviews.llvm.org/D138025/new/

https://reviews.llvm.org/D138025