[llvm] [DAGCombiner] Avoid illegal scalar nodes in estimate refinement (PR #219394)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,419 @@
+; NOTE: Do not autogenerate
+; RUN: split-file %s %t
+; RUN: llc -O3 -stop-after=finalize-isel %t/estimate.ll -o - | FileCheck %s --check-prefix=MIR --enable-var-scope
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arsenm wrote:

-O3 shouldn't be needed 

https://github.com/llvm/llvm-project/pull/219394