[llvm] [RISCV] Don't remove extends for i1 indices in mgather/mscatter (PR #83951)

[Wang Pengcheng via llvm-commits]

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@@ -20043,8 +20043,9 @@ bool RISCVTargetLowering::shouldRemoveExtendFromGSIndex(SDValue Extend,
   // We have indexed loads for all legal index types.  Indices are always
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wangpc-pp wrote:

Oh, we need reword these comments.

https://github.com/llvm/llvm-project/pull/83951