[llvm] [Coroutines] ABI Objects to improve code separation between different ABIs, users and utilities. (PR #109338)

[Chuanqi Xu via llvm-commits]

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@@ -21,19 +21,26 @@
 
 namespace llvm {
 
+namespace coro {
+class BaseABI;
+class Shape;
+} // namespace coro
+
 struct CoroSplitPass : PassInfoMixin<CoroSplitPass> {
-  const std::function<bool(Instruction &)> MaterializableCallback;
+  // BaseABITy generates an instance of a coro ABI.
+  using BaseABITy = std::function<coro::BaseABI *(Function &, coro::Shape &)>;
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ChuanqiXu9 wrote:

Let's move the definition and its use closer. And also `BaseABITy` may not be good name. If it is only used once, maybe it is not to not give it a name right now.

https://github.com/llvm/llvm-project/pull/109338