[llvm] [DropUnnecessaryAssumes] Make the ephemeral value check more precise (PR #160700)

[Ramkumar Ramachandra via llvm-commits]

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@@ -1,6 +1,9 @@
 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 6
 ; RUN: opt -S -passes=drop-unnecessary-assumes < %s | FileCheck %s
 
+declare void @use(i32 %x)
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artagnon wrote:

Could use llvm.fake.use?

https://github.com/llvm/llvm-project/pull/160700