[llvm] [LoopStrengthReduce] Mitigation of issues introduced by compilation time optimization in SolveRecurse. (PR #147588)

[Matt Arsenault via llvm-commits]

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@@ -5387,6 +5428,10 @@ void LSRInstance::SolveRecurse(SmallVectorImpl<const Formula *> &Solution,
 
   const LSRUse &LU = Uses[Workspace.size()];
 
+  assert(LU.Formulae.size() &&
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arsenm wrote:

```suggestion
  assert(!LU.Formulae.empty() &&
```

https://github.com/llvm/llvm-project/pull/147588