[llvm] Reland "[LICM] Sink unused l-invariant loads in preheader #157559" (PR #170204)

[Nikita Popov via llvm-commits]

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@@ -0,0 +1,28 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 6
+; RUN: opt < %s -passes=licm -verify-memoryssa -S | FileCheck %s
+
+declare i1 @b()
+
+define i32 @a(i32 %x) nounwind {
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nikic wrote:

```suggestion
define i32 @a(i32 %x) {
```

https://github.com/llvm/llvm-project/pull/170204