[llvm] [GlobalISel] Combine (X >> C) << C to X & ((-1 >> C) << C) (PR #114821)

[Jay Foad via llvm-commits]

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@@ -933,6 +933,17 @@ class GShl : public GenericMachineInstr {
   };
 };
 
+/// Represents a logical shift right.
+class GLshr : public GenericMachineInstr {
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jayfoad wrote:

Should be "LShr" not "Lshr".

https://github.com/llvm/llvm-project/pull/114821