[llvm] [CodeGen] Add MO_LaneMask type and a new COPY_LANEMASK instruction (PR #151944)

[Jay Foad via llvm-commits]

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@@ -49,6 +49,7 @@ namespace llvm {
     constexpr bool operator== (LaneBitmask M) const { return Mask == M.Mask; }
     constexpr bool operator!= (LaneBitmask M) const { return Mask != M.Mask; }
     constexpr bool operator< (LaneBitmask M)  const { return Mask < M.Mask; }
+    constexpr bool operator<=(LaneBitmask M) const { return Mask <= M.Mask; }
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jayfoad wrote:

Remove this

https://github.com/llvm/llvm-project/pull/151944