[llvm] [DAG] Fold trunc(avg(x, y)) for avgceil/floor u/s nodes if they have sufficient leading zero/sign bits (PR #152273)

[Simon Pilgrim via llvm-commits]

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@@ -0,0 +1,43 @@
+; RUN: llc -mtriple=aarch64-- -O2 -mattr=+neon < %s | FileCheck %s
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RKSimon wrote:

Use update_llc_test_checks.py script to generate the full checks

https://github.com/llvm/llvm-project/pull/152273