[llvm] [InstCombine] Add user-count bailout to isAllocSiteRemovable (PR #190347)

[Yingwei Zheng via llvm-commits]

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@@ -0,0 +1,19 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt -passes=instcombine -S < %s | FileCheck %s
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dtcxzyw wrote:

```suggestion
; RUN: opt -passes=instcombine -S < %s | FileCheck %s --check-prefix=OPT
; RUN: opt -passes=instcombine -instcombine-max-allocsite-removable-users=1 -S < %s | FileCheck %s --check-prefix=NOOPT
```


https://github.com/llvm/llvm-project/pull/190347