[llvm] [Instcombine] Ensure simplifyValueKnownNonZero adds instrs in dominance order. (PR #173703)

[Nikita Popov via llvm-commits]

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@@ -0,0 +1,13 @@
+; NOTE: This test ensures InstCombine preserves dominance even when it
+; reorders shifts through SimplifyDemandedBits/log2 folding.
+;
+; RUN: opt -passes=instcombine,verify -disable-output %s
----------------
nikic wrote:

```suggestion
; RUN: opt -passes=instcombine < %s | FileCheck %s
```
Please check the output even if it's a crash regression test.

https://github.com/llvm/llvm-project/pull/173703