[llvm] [Instcombine] Fix crash in foldMinimumMaximumSharedOp. (PR #173705)

[Justin Lebar via llvm-commits]

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@@ -0,0 +1,16 @@
+; RUN: opt -passes=instcombine -S %s -o - | FileCheck %s
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jlebar wrote:

Are you sure that's a good idea?  That would change this reproducer into a "change-detector test".  Change-detector tests are fragile by construction.  And when they do fail, it's not clear whether the new IR is "acceptable" / "correct".

It's been my practice to write tests that check for "correctness" or "no regression" and no more.  In this case "no regression" would mean "LLVM doesn't crash".

WDYT?

https://github.com/llvm/llvm-project/pull/173705