[llvm] [LLVM] Add flatten function attribute to LLVM IR and implement recursive inlining in AlwaysInliner (PR #174899)

[Nikita Popov via llvm-commits]

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@@ -3443,3 +3443,16 @@ llvm::InlineResult llvm::InlineFunction(CallBase &CB, InlineFunctionInfo &IFI,
 
   return Result;
 }
+
+bool llvm::inlineHistoryIncludes(
+    Function *F, int InlineHistoryID,
+    const SmallVectorImpl<std::pair<Function *, int>> &InlineHistory) {
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nikic wrote:

```suggestion
    ArrayRef<std::pair<Function *, int>> InlineHistory) {
```

https://github.com/llvm/llvm-project/pull/174899