[llvm] [SelectionDAG] Propogate Disjoint flag. (PR #88370)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,22 @@
+; NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py
+; RUN: llc -mtriple=x86_64 %s -start-before=x86-isel -o - -stop-after=x86-isel | FileCheck %s
+
+define void @add_shl_or_disjoint(i32 %x, ptr addrspace(1) %o) {
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arsenm wrote:

I don't think this test should be using MIR. If there's an observable codegen change, this should just check the final ISA. A MIR test would be the right choice if it was only showing the flag survived through selection, but I don't see it here 

https://github.com/llvm/llvm-project/pull/88370